Search

Aim: To evaluate the impact of palbociclib treatment on health-related quality of life (HRQoL) in patients with hormone receptor-positive, human epidermal growth factor 2-negative advanced breast cancer (HR+/HER2- aBC) or metastatic breast cancer (mBC) in both the clinical and real-world setting. Materials & methods: A systematic literature review was conducted to identify clinical trials and real-world evidence studies up to June 2023 that reported HRQoL outcomes in patients with HR+/HER2- aBC or mBC treated with Palbociclib. Results: 15 unique studies reported across 35 records were identified. Of these, seven were randomized controlled trials (RCTs), three were single-arm clinical trials and five were real-world evidence (RWE) studies. HRQoL was generally found to be maintained in patients with HR+/HER2- aBC or mBC across RCTs, single-arm clinical trials and RWE studies. HRQoL measures across instruments, study types and line of therapy, were largely reported to be at least maintained if not improved from baseline among patients treated with palbociclib and were observed to be comparable or better in the palbociclib group versus monotherapy control arm in RCTs. Similar results were seen for treatment-related outcomes (e.g., sexual functioning, upset by hair loss, systemic therapy side effects etc.), and important individual patient outcomes, including pain, fatigue and physical functioning. Findings were also consistent across key clinical characteristics (visceral metastases, neutropenia), as well as patient populations often underrepresented in clinical trials (Asian patients, older adults). Conclusion: Overall, current evidence suggests that HRQoL is largely preserved with the addition of palbociclib to endocrine therapy in patients with HR+/HER2- aBC or mBC across study types and populations.

Background: The management of early breast cancer (BC) has witnessed an uprise in the use of neoadjuvant therapy and a remarkable reshaping of the systemic therapy postneoadjuvant treatment in the last few years, with the evolution of many controversial clinical situations that require consensus., Methods: During the 14th Breast-Gynecological and Immuno-Oncology International Cancer Conference held in Egypt in 2022, a panel of 44 BC experts from 13 countries voted on statements concerning debatable challenges in the neo/adjuvant treatment setting. The recommendations were subsequently updated based on the most recent data emerging. A modified Delphi approach was used to develop this consensus. A consensus was achieved when ≥75% of voters selected an answer., Results and Conclusions: The consensus recommendations addressed different escalation and de-escalation strategies in the setting of neoadjuvant therapy for early BC. The recommendations recapitulate the available clinical evidence and expert opinion to individualize patient management and optimize therapy outcomes. Consensus was reached in 63% of the statements (52/83), and the rationale behind each statement was clarified., (© 2024 American Cancer Society.)

This manuscript describes the Advanced Breast Cancer (ABC) international consensus guidelines updated at the last two ABC international consensus conferences (ABC 6 in 2021, virtual, and ABC 7 in 2023, in Lisbon, Portugal), organized by the ABC Global Alliance. It provides the main recommendations on how to best manage patients with advanced breast cancer (inoperable locally advanced or metastatic), of all breast cancer subtypes, as well as palliative and supportive care. These guidelines are based on available evidence or on expert opinion when a higher level of evidence is lacking. Each guideline is accompanied by the level of evidence (LoE), grade of recommendation (GoR) and percentage of consensus reached at the consensus conferences. Updated diagnostic and treatment algorithms are also provided. The guidelines represent the best management options for patients living with ABC globally, assuming accessibility to all available therapies. Their adaptation (i.e. resource-stratified guidelines) is often needed in settings where access to care is limited., Competing Interests: Declaration of competing interest Matti S. Aapro: Consultant for Accord Pharmaceuticals, Amgen, BMS, Celgene, Clinigen Group, Daiichi Sankyo, Eisai Co.Ltd, Eli Lilly, Genomic Health (Exact Sciences), G1 Therapeutics, Inc., GlaxoSmithKline (GSK), Helsinn Healthcare SA, Hospira (Pfizer), Johnson & Johnson, Merck, Merck Serono (Merck KGaA), Mundipharma International Limited, Novartis, Pfizer, Pierre Fabre, Roche, Sandoz, Tesaro (GSK), Teva Pharmaceuticals Industries Ltd., Vifor Pharma. Received honoraria for lectures at symposia of Accord Pharmaceuticals, Amgen, Astellas, Bayer HealthCare Pharmaceuticals (Schering), Biocon, Boeringer Ingelheim, Cephalon, Chugai Pharmaceutical Co., Ltd., Daiichi Sankyo, Eisai Co., Ltd., Dr Reddy's Laboratories, Genomic Health (Exact Sciences), Glenmark Pharmaceuticals Limited, GSK, Helsinn Healthcare SA, Hospira (Pfizer), Ipsen, Janssen Biotech, Kyowa Kirin Group, Merck, Merck Serono (Merck KGaA), Mundipharma International Limited, Novartis, Pfizer, Pierre Fabre, Roche, Sandoz, Sanofi, Tesaro (GSK), Taiho Pharmaceutical, Teva Pharmaceutical Industries Ltd., Vifor Pharma. Grant/Research supports: Amgen, Eisai, Genomic Health (Exact Sciences), Helsinn, Hospira, Novartis, Merck, Mundipharma, Pfizer, Roche, Sandoz, Tesaro, Teva, Vifor. Jyoti Bajpai: Institutional financial interests for conducting research: Eli Lilly, MSD, Novartis, Roche, Paxman Coolers Ltd, Samsung Bioepis co. Ltd, Sun Pharma. Carlos H. Barrios: Receipt of grants/research supports: (to the institution) Nektar, Pfizer, Polyphor, Amgen, Daiichi Sankyo, Sanofi, Exelixis, Regeneron, Novartis, GSK, Janssen, OBI Pharma, Lilly, Seagen, Roche, BMS, MSD, Merck Serono, AstraZeneca, Novocure, Aveo Oncology, Takeda, TRIO, PharmaMar, Celgene, PPD, Syneos Health, Labcorp, ICON, IQVIA, Parexel, Nuvisan, PSI, Worldwide, Gilead Sciences, Bayer, Servier. Receipt of honoraria or consultation fees: Advisory Boards and Consulting: Boehringer-Ingelheim, GSK, Novartis, Pfizer, Roche/Genentech, Eisai, Bayer, MSD, AstraZeneca, Zodiac, Lilly, Sanofi, Daiichi. Stock shareholder: Ownership or stocks: Tummi, MEDSir. Jonas Bergh: Receipt of grants/research supports: Research grants from Amgen, AstraZeneca, Bayer, Merck, Pfizer, Roche & Sanofi-Aventis to Karolinska Institutet and/or University Hospital. No personal payments. Other support: Payment for a chapter in UpToDate on breast cancer prediction to Asklepios Medicin HB. Laura Biganzoli: Personal financial interests (Honoraria, consultancy or advisory role): Amgen, AstraZeneca, Boehringer-Ingelheim, Daiichi-Sankyo, Eisai, Exact Sciences, Gilead, Lilly, Menarini, Novartis, Pfizer, Pierre Fabre, Roche, Sanofi, SeaGen. Institutional financial interests: Celgene, Genomic Health, Novartis. Travel grants: AstraZeneca, Daiichi-Sankyo. Fatima Cardoso: Receipt of honoraria or consultation fees: Amgen, Astellas/Medivation, AstraZeneca, Celgene, Daiichi-Sankyo, Eisai, GE Oncology, Genentech, Gilead, GlaxoSmithKline, Iqvia, Macrogenics, Medscape, Merck-Sharp, Merus BV, Mylan, Mundipharma, Novartis, Pfizer, Pierre-Fabre, prIME Oncology, Roche, Sanofi, Samsung Bioepis, Seagen, Teva, Touchime. Maria-Joao Cardoso: Receipt of honoraria or consultation fees: AstraZeneca, Merck-Sharp, Novartis and Roche. Lisa A. Carey: Other support: Research funding (institution): NanoString Technologies, Seagen, Veracyte, AstraZeneca. Uncompensated relationships: Lilly, Seagen, Novartis, Genentech/Roche, GlaxoSmithKline. Mariana Chavez-MacGregor: Receipt of grants/research supports: BCRF, Susan G Komen. Receipt of honoraria or consultation fees: Astra Zeneca, Pfizer, Lilly, Roche, Merck. Javier Cortés: Receipt of grants/research supports: Roche, Celgene, Cellestia, AstraZeneca, Seattle Genetics, Daiichi Sankyo, Erytech, Athenex, Polyphor, Lilly, Merck Sharp&Dohme, GSK, Leuko, Bioasis, Clovis Oncology, Boehringer Ingelheim, Ellipses, Hibercell, BioInvent, Gemoab, Gilead, Menarini, Zymeworks, Reveal Genomics, Expres2ion Biotechnologies. Receipt of honoraria or consultation fees: Roche, Novartis, Celgene, Eisai, Pfizer, Samsung Bioepis, Lilly, Merck Sharp&Dohme, Daiichi Sankyo, Astrazeneca. Stock shareholder: MedSIR, Nektar Pharmaceuticals, Leuko (relative). Other support: Research funding to the Institution: Roche, Ariad pharmaceuticals, AstraZeneca, Baxalta GMBH/Servier Affaires, Bayer healthcare, Eisai, F.Hoffman-La Roche, Guardanth health, Merck Sharp&Dohme, Pfizer, Piqur Therapeutics, Puma C, Queen Mary University of London. Travel, accommodation, expenses: Roche, Novartis, Eisai, pfizer, Daiichi Sankyo, Astrazeneca, Gilead. Patents: Pharmaceutical Combinations of a Pi3k Inhibitor and A Microtubule Destabilizing Agent. Javier Cortés Castán, Alejandro Piris Giménez, Violeta Serra Elizalde. WO 2014/199294 A. ISSUED. Her2 as a predictor of response to dual HER2 blockade in the absence of cytotoxic therapy. Aleix Prat, Antonio Llombart, Javier Cortés.US 2019/0338368 A1. LICENSED. Giuseppe Curigliano: Receipt of grants/research supports: Merck. Receipt of honoraria or consultation fees: Merck, Lilly, Pfizer, Daichi Sankyo, Seagen, Novartis, Roche, Astra Zeneca, Ellipsis. Participation in a sponsored speakers' bureau: Seagen, Novartis, Lilly, Pfizer, Daichii Sankyo. Rebecca A. Dent: Receipt of grants/research supports: AstraZeneca, Roche. Receipt of honoraria or consultation fees: AstraZeneca, DKSH, Eisai, Merck, Novartis, Pfizer, Roche. Nagi S. El Saghir: Receipt of honoraria or consultation fees: Roche, Novartis, Lilly. Alexandru Eniu: Receipt of honoraria or consultation fees: Astra Zeneca, Daiichi Sankyo, Gilead, Janssen, MSD, Novartis, SeaGen. Receipt of grants/research supports: AstraZeneca. Full or part-time employment: European School of Oncology (ESO). Lesley Fallowfield: Receipt of grants/research supports: Novartis, Bristol-Myers Squibb, Lilly. Receipt of honoraria or consultation fees: Voluntis, Genomic Health, NanoString Technologies, Novartis, Pfizer, MSD, Novartis, Abbvie, Clovis Oncology, Puma Biotechnology, AstraZeneca, Takeda, Genomic Health/Exact Sciences, Lilly, Seagen, Roche. Sandra X. Franco Millan: Receipt of honoraria or consultation fees: Novartis, Pfizer, Eli Lilly. Participation in a sponsored speakers' bureau: Novartis, Pfizer, Eli Lilly. Karen Gelmon: Receipt of grants/research supports: Pfizer, AstraZeneca. Receipt of honoraria or consultation fees: Pfizer, Lilly, Novartis, AstraZeneca, Merck, Gilead, Seagen. Jenny Gilchrist: Receipt of honoraria or consultation fees: Eli-Lilly, AstraZeneca, Novartis, Pfizer, MSD, Gilead, Juniper Biologics. Joseph Gligorov: Receipt of grants/research supports: Eisai, Exact Science, Guardant, Roche Genentech. Receipt of honoraria or consultation fees: Astra Zeneca, Daiichi, Eisai, Evapharma, Exact Science, Gilead, Guardant Lilly, Merck, Novartis, Onxeo, Pfizer, Roche Genentech, Seattle Genetics. Participation in a sponsored speakers' bureau: Eisai, Eva Pharm, Novartis, Roche Genentech, Seattle Genetics. Other support (please specify): Institutional: Institut Universitaire de Cancérologie AP-HP Sorbonne Université; French breast cancer guidelines St Paul. Nadia Harbeck: Receipt of grants/research supports: all to institution. Receipt of honoraria or consultation fees: AstraZeneca, Daiichi-Sankyo, Gilead, Lilly, MSD, Novartis, PierreFabre, Pfizer, Roche, Sandoz, Seagen, Viatris, Zuelligpharma. Participation on a sponsored speakers' bureau: EPG Communication, MEDSCAPE, Springer. Stock shareholder: WSG minority ownership. Spouse/Partner: Consulting for WSG. Ranjit Kaur: Receipt of grants/research supports: Novartis, Roche, Pfizer, Astrazeneca. Receipt of honoraria or consultation fees: Novartis, Roche, Pfizer, Astrazeneca. Participation in a sponsored speakers' bureau: Novartis, Roche, Pfizer, Astrazeneca. Belinda Kiely: Receipt of honoraria or consultation fees: Speakers fees: Novartis, Eisai. Advisory boards: Roche, Gilead, Novartis. Other support (please specify): meeting registrations fees: Novartis, Pfizer, MSD. Sung-Bae Kim: Receipt of grants/research supports: Novartis, Sanofi-Aventis, and DongKook Pharm Co. Receipt of honoraria or consultation fees: Novartis, AstraZeneca, Lilly, Dae Hwa Pharmaceutical Co. Ltd, ISU Abxis, OBI pharma, Beigene and Daiichi-Sankyo. Stock shareholder: Genopeaks. Smruti Koppikar: Receipt of honoraria or consultation fees: Eli Lilly, Novartis, Cipla, Roche. Participation in a sponsored speakers' bureau: Eli Lilly, Novartis, Cipla, Roche. Marion Kuper-Hommel: Receipt of honoraria or consulting fees: Astra Zeneca. Ginny Mason: Participation in a sponsored speakers' bureau: Novartis. Volkmar Mueller: Receipt of grants/research supports: Institutional research support from Novartis, Roche, Seagen, Genentech, Astra Zeneca. Receipt of honoraria or consultation fees: Speaker honoraria: Astra Zeneca, Daiichi-Sankyo, Eisai, GSK, Pfizer, MSD, Medac, Novartis, Roche, Seagen, Onkowissen, high5 Oncology, Medscape, Gilead, Pierre Fabre. Consultancy honoraria from Roche, Pierre Fabre, Amgen, ClinSol, Novartis, MSD, DaiichiSankyo, Eisai, Lilly, Sanofi, Seagen, Gilead, Stemline, ClinSol. Other support (please specify): Travel grants: Roche, Pfizer, Daiichi Sankyo, Gilead. Claire Myerson: Receipt of honoraria or consultation fees: Novartis Pharma. Silvia Neciosup: Receipt of grants/research supports: Roche, Pfizer. Participation in a sponsored speakers' bureau: Tecnofarma, AZ, Roche, Pfizer. Larry Norton: Receipt of honoraria or consultation fees: Blackrock QLS Advisors, Cold Spring Harbor Laboratory, UNC Breast Spore EAB Meeting, Codagenix Scientific Advisory Board Meeting, Martell Diagnostic Laboratories, Inc., Celgene, Agenus, Immix Biopharma, Inc. Shinji Ohno: Participation in a sponsored speakers' bureau: Chugai, Lilly, MSD, Nippon Kayaku. Shani Paluch-Shimon: Receipt of grants/research supports: Pfizer. Receipt of honoraria or consultation fees: Pfizer, Lily, Novartis, Astra Zeneca, Roche, MSD, Gilead, Rhenium/Exact Sciences, Stemline, Daichi Sankyo. Participation in a sponsored speakers' bureau: Pfizer, Lily, Novartis, Astra Zeneca, Roche, MSD, Gilead. Ann H. Partridge: Uptodate Royalties. Aleix Prat: Receipt of grants/research supports: Boehringer, Novartis, Roche, Nanostring, Sysmex Europa GmbH, Medica Scientia inno. Research, SL, Celgene, Astellas and Pzifer. Receipt of honoraria or consultation fees: Roche, Pfizer, Novartis, Amgen, BMS, Puma, Oncolytics Biotech, MSD, Guardan Health, Peptomyc and Lilly, Nanostring Technologies and Daiichi Sankyo. Other support: Clinical trials: Boehringer, Lilly, Roche, Novartis, Amgen and Daiichi Sankyo. Hope S. Rugo: Receipt of grants/research supports: Astellas Pharma Inc.; AstraZeneca; Daiichi Sankyo, Inc.; F. Hoffmann-La Roche AG/Genentech, Inc.; Gilead Sciences, Inc.; GlaxoSmithKline; Lilly; Merck & Co., Inc.; Novartis Pharmaceuticals Corporation; Pfizer; Pionyr Immunotherapeutics; Sermonix Pharmaceuticals Inc.; Taiho Oncology, Inc. and Veru Inc. Receipt of honoraria or consultation fees: Puma, NAPO, Blueprint, and Scorpion Therapeutics Daichi Sankyo. Elzbieta Senkus: Receipt of honoraria or consultation fees: AstraZeneca, Curio Science, Egis, Eli Lilly, Gilead, high5md, MSD, Novartis, Pfizer, Roche, Swixx. Other support: travel support: AstraZeneca, Egis, Gilead, Novartis, Roche. Contracted research: Amgen, AstraZeneca, Eli Lilly, Gilead, Novartis, OBI Pharma, Roche, Samsung, Seagen. Medical writing: AstraZeneca, Eli Lilly. Royalties: Springer. Sandra M. Swain: Receipt of grants/research supports: Kailos Genetics, Genentech/Roche. Receipt of honoraria or consultation fees: Athenex, AstraZeneca, Biotheranostics, Natera, Exact Sciences, Lilly, Merck, Genentech/Roche, Sanofi, Daiichi Sankyo, Molecular Templates, Napo Pharmaceuticals. Stock shareholder: SEAGEN. Other support: CO- PI of INAVO 122 Genentech/Roche with in-kind travel to investigator meetings, Travel related expenses in kind Sanofi and Daiichi Sankyo. Peter Vuylsteke: Receipt of grants/research supports: UICC grant. Receipt of honoraria or consultation fees: Roche, Novartis and MSD. Theresa Wiseman: Receipt of grants/research supports: Receiver of SPCC Pfizer grant. Binghe Xu: Receipt of grants/research supports: sponsored research to my institution from Roche, AstraZeneca and Pfizer. Receipt of honoraria or consultation fees: advisory or consultancy fees from Novartis and Roche. Participation in a sponsored speakers' bureau: speakers’ bureau fees from AstraZeneca, Pfizer, Roche, Eisai. Elizabeth Bergsten-Nordström, Alberto Costa, Runcie C. W. Chidebe, Prudence A. Francis, Xichun Hu, Renate Haidinger, Leonor Matos, Shirley A. Mertz, Birgitte V. Offersen, Olivia Pagani, Eva Schumacher-Wulf, Daniel A. Vorobiof, Frédéric E. Lecouvet, and Eric P. Winer reported no significant relationships. William J. Gradishar, George W. Sledge and Christoph Thomssen have not submitted a disclosure of interests’ form., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Invasive lobular carcinoma (ILC) is the second most frequent type of breast cancer (BC) and its peculiar morphology is mainly driven by inactivation of CDH1, the gene coding for E-cadherin cell adhesion protein. ILC-specific therapeutic and disease-monitoring approaches are gaining momentum in the clinic, increasing the importance of accurate ILC diagnosis. Several essential and desirable morphologic diagnostic criteria are currently defined by the World Health Organization, the routine use of immunohistochemistry (IHC) for E-cadherin is not recommended. Disagreement in the diagnosis of ILC has been repeatedly reported, but interpathologist agreement increases with the use of E-cadherin IHC. In this study, we aimed to harmonize the pathological diagnosis of ILC by comparing 5 commonly used E-cadherin antibody clones (NCH-38, EP700Y, Clone 36, NCL-L-E-cad [Clone 36B5], and ECH-6). We determined their biochemical specificity for the E-cadherin protein and IHC staining performance according to type and location of mutation on the CDH1 gene. Western blot analysis on mouse cell lines with conditional E-cadherin expression revealed a reduced specificity of EP700Y and NCL-L-E-cad for E-cadherin, with cross-reactivity of Clone 36 to P-cadherin. The use of IHC improved interpathologist agreement for ILC, lobular carcinoma in situ, and atypical lobular hyperplasia. The E-cadherin IHC staining pattern was associated with variant allele frequency and likelihood of nonsense-mediated RNA decay but not with the type or position of CDH1 mutations. Based on these results, we recommend the indication for E-cadherin staining, choice of antibodies, and their interpretation to standardize ILC diagnosis in current pathology practice., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Purpose: To summarize the radiotherapy-relevant statements of the 18th St. Gallen Breast Cancer Consensus Conference and interpret the findings in light of German guideline recommendations., Methods: Statements and voting results from the 18th St. Gallen International Breast Cancer Consensus Conference were collected and analyzed according to their relevance for the radiation oncology community. The voting results were discussed in two hybrid meetings among the authors of this manuscript on March 18 and 19, 2023, in light of the German S3 guideline and the 2023 version of the Arbeitsgemeinschaft Gynäkologische Onkologie (AGO) guidelines., Results and Conclusion: There was a high level of agreement between the radiotherapy-related statements of the 18th St. Gallen International Breast Cancer Consensus Conference and the German S3 and AGO guidelines. Discrepancies include the impact of number of lymph node metastases for the indication for postmastectomy radiotherapy., (© 2024. The Author(s).)

The European Society for Radiotherapy and Oncology (ESTRO) has advocated the establishment of guidelines to optimise precision radiotherapy (RT) in conjunction with contemporary therapeutics for cancer care. Quality assurance in RT (QART) plays a pivotal role in influencing treatment outcomes. Clinical trials incorporating QART protocols have demonstrated improved survival rates with minimal associated toxicity. Nonetheless, in routine clinical practice, there can be variability in the indications for RT, dosage, fractionation, and treatment planning, leading to uncertainty. In pivotal trials reporting outcomes of systemic therapy for breast cancer, there is limited information available regarding RT, and the potential interaction between modern systemic therapy and RT remains largely uncharted. This article is grounded in a consensus recommendation endorsed by ESTRO, formulated by international breast cancer experts. The consensus was reached through a modified Delphi process and was presented at an international meeting convened in Florence, Italy, in June 2023. These recommendations are regarded as both optimal and essential standards, with the latter aiming to define the minimum requirements. A template for a case report form (CRF) has been devised, which can be utilised by all clinical breast cancer trials involving RT. Optimal requirements include adherence to predefined RT planning protocols and centralised QART. Essential requirements aim to reduce variations and deviations from the guidelines in RT, even when RT is not the primary focus of the trial. These recommendations underscore the significance of implementing these practices in both clinical trials and daily clinical routines to generate high-quality data., Competing Interests: Declaration of competing interest IMe declares advisory boards supported by Eli Lilly, Novartis, Pfizer, Pierre Fabre, SeaGen, Daiichi Sankyo, Astra Zeneca. CB declares honoraria supported by declares advisory boards supported by Eli Lilly, Novartis, Pfizer, and Amgen. ML received honoraria and/or participated in advisory board from Roche, Novartis, Lilly, Pfizer, AstraZeneca, Daiichi Sankyo, Gilead, SeaGen, MSD, Exact Sciences, Takeda, Ipsen, Sandoz, Libbs & Knight, a travel grant from Gilead and research support to the Institution from Gilead. EdA disclosed honoraria and/or advisory board from Roche/GNE, Novartis, SeaGen, Zodiac, Libbs, Pierre Fabre, Lilly, AstraZeneca. JC disclosed consulting/advisor for Roche, Celgene, Cellestia, AstraZeneca, SeaGen, Daiichi Sankyo, Erytech, Athenex, Polyphor, Lilly, Merck Sharp & Dohme, GSK, Leuko, Bioasis, Clovis Oncology, Boehringer Ingelheim, Ellipses, Hibercell, BioInvent, Gemoab, Gilead, Menarini, Zymeworks, Reveal Genomics, Expres2ion Biotechnologies. NH disclosed honoraria for lectures and/or consulting from AstraZeneca, Daiichi-Sankyo, Gilead, Lilly, MSD, Novartis, Pierre-Fabre, Pfizer, Roche, Sanofi, Sandoz, SeaGen. HSR disclosed institutional research support by Astellas Pharma Inc., AstraZeneca, Daiichi Sankyo Inc., F. Hoffmann-La Roche AG/Genentech, Inc., Gilead Sciences Inc., GlaxoSmithKline, Lilly, Merck & Co. Inc., Novartis Pharmaceuticals Corporation, OBI Pharma, Pfizer, Pionyr Immunotherapeutics, Sermonix Pharmaceuticals Inc., Taiho Oncology Inc., and Veru Inc. GC reports personal fees for consulting, advisory role and speakers’ bureau from Roche/Genentech, Novartis, Pfizer, Lilly, Foundation Medicine, Samsung and Daiichi Sankyo; honoraria from Ellipses Pharma and fees for travel and accommodations from Roche/Genentech and Pfizer. LV declares participation on advisory board from Daiichi Sankyo and Pfizer. ME declares advisory board supported by Pfizer and Novartis and lecture fees supported by AstraZeneca. GM declares consultancy honoraria from Roche, Novartis, AstraZeneca, Pfizer, Jensen, Lilly, and Sanofi. LDM declares consulting fees from Roche, Novartis, Eli Lilly, MSD, Daiichi Sankyo, SeaGen, Gilead, Eisai, Pierre Fabre, AstraZeneca, Stemline Menarini, Exact Sciences, Agendia, GSK, Pfizer. No other competing interests declared., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: 18 F-fluoroestradiol (FES) positron emission tomography (PET)/computed tomography (CT) is considered an accurate diagnostic tool to determine whole-body endocrine responsiveness. In the endocrine therapy (ET)-FES trial, we evaluated 18 F-FES PET/CT as a predictive tool in estrogen receptor-positive (ER+)/human epidermal growth factor receptor 2-negative (HER2-) metastatic breast cancer (MBC)., Patients and Methods: Eligible patients underwent an 18 F-FES PET/CT at baseline. Patients with standardized uptake value (SUV) ≥ 2 received single-agent ET until progressive disease; patients with SUV < 2 were randomized to single-agent ET (arm A) or chemotherapy (ChT) (arm B). The primary objective was to compare the activity of first-line ET versus ChT in patients with 18 F-FES SUV < 2., Results: Overall, 147 patients were enrolled; 117 presented with 18 F-FES SUV ≥ 2 and received ET; 30 patients with SUV < 2 were randomized to ET or ChT. After a median follow-up of 62.4 months, 104 patients (73.2%) had disease progression and 53 died (37.3%). Median progression-free survival (PFS) was 12.4 months [95% confidence interval (CI) 3.1-59.6 months] in patients with SUV < 2 randomized to arm A versus 23.0 months (95% CI 7.7-30.0 months) in arm B, [hazard (HR) = 0.71, 95% CI 0.3-1.7 months]; median PFS was 18.0 months (95% CI 11.2-23.1 months) in patients with SUV ≥ 2 treated with ET. Median overall survival (OS) was 28.2 months (95% CI 14.2 months-not estimable) in patients with SUV < 2 randomized to ET (arm A) versus 52.8 months (95% CI 16.2 months-not estimable) in arm B (ChT). Median OS was not reached in patients with SUV ≥ 2. 60-month OS rate was 41.6% (95% CI 10.4% to 71.1%) in arm A, 42.0% (95% CI 14.0% to 68.2%) in arm B, and 59.6% (95% CI 48.6% to 69.0%) in patients with SUV ≥ 2. In patients with SUV ≥ 2, 60-month OS rate was 72.6% if treated with aromatase inhibitors (AIs) versus 40.6% in case of fulvestrant or tamoxifen (P < 0.005)., Conclusions: The ET-FES trial demonstrated that ER+/HER2- MBC patients are a heterogeneous population, with different levels of endocrine responsiveness based on 18 F-FES CT/PET SUV., Competing Interests: Disclosure The authors have declared no conflicts of interest., (Copyright © 2024. Published by Elsevier Ltd.)

In DESTINY-Breast04 (DB-04), safety and efficacy of HER2-targeted antibody-drug conjugate (ADC) trastuzumab deruxtecan (T-DXd) in previously treated HER2-low unresectable/metastatic breast cancer were established. This manuscript describes the analytical validation of PATHWAY Anti-HER2/neu (4B5) Rabbit Monoclonal Primary Antibody (PATHWAY HER2 (4B5)) to assess HER2-low status and its clinical performance in DB-04. Preanalytical processing and tissue staining parameters were evaluated to determine their impact on HER2 scoring. The recommended antibody staining procedure provided the optimal tumor staining, and deviations in cell conditioning and/or antibody incubation times resulted in unacceptable negative control staining and/or HER2-low status changes. Comparisons between antibody lots, kit lots, instruments, and day-to-day runs showed overall percent agreements (OPAs) exceeding 97.9%. Inter-laboratory reproducibility showed OPAs of ≥97.4% for all study endpoints. PATHWAY HER2 (4B5) was utilized in DB-04 for patient selection using 1340 tumor samples (59.0% metastatic, 40.7% primary, (0.3% missing data); 74.3% biopsy, 25.7% resection/excisions). Overall, 77.6% (823/1060) of samples were HER2-low by both central and local testing, with the level of concordance differing by sample region of origin and collection date. In DB-04, the efficacy of T-DXd over chemotherapy of physician's choice was consistent, regardless of the characteristics of the sample used (primary or metastatic, archival, or newly collected, biopsy or excision/resection). These results demonstrate that PATHWAY HER2 (4B5) is precise and reproducible for scoring HER2-low status and can be used with multiple breast cancer sample types for reliably identifying patients whose tumors have HER2-low expression and are likely to derive clinical benefit from T-DXd., (© 2023. The Author(s).)

The European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of patients with early breast cancer were updated and published online in 2023, and adapted, according to previously established standard methodology, to produce the Pan-Asian adapted (PAGA) ESMO consensus guidelines for the management of Asian patients with early breast cancer. The adapted guidelines presented in this manuscript represent the consensus opinions reached by a panel of Asian experts in the treatment of patients with breast cancer representing the oncological societies of China (CSCO), Indonesia (ISHMO), India (ISMPO), Japan (JSMO), Korea (KSMO), Malaysia (MOS), the Philippines (PSMO), Singapore (SSO), Taiwan (TOS) and Thailand (TSCO), co-ordinated by ESMO and KSMO. The voting was based on scientific evidence and was independent of the current treatment practices, drug access restrictions and reimbursement decisions in the different Asian regions represented by the 10 oncological societies. The latter are discussed separately in the manuscript. The aim is to provide guidance for the optimisation and harmonisation of the management of patients with early breast cancer across the different regions of Asia, drawing on the evidence provided by both Western and Asian trials, whilst respecting the differences in screening practices, molecular profiling, as well as the age and stage at presentation. Attention is drawn to the disparity in the drug approvals and reimbursement strategies, between the different regions of Asia., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical trial updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported. Two years of adjuvant abemaciclib combined with endocrine therapy (ET) resulted in a significant improvement in invasive disease-free survival (IDFS) and distant relapse-free survival (DRFS) that persisted beyond the 2-year treatment period in patients with hormone receptor-positive, human epidermal growth factor receptor 2-negative, node-positive, high-risk early breast cancer (EBC). Here, we report 5-year efficacy results from a prespecified overall survival (OS) interim analysis. In the intent-to-treat population, with a median follow-up of 54 months, the benefit of abemaciclib was sustained with hazard ratios of 0.680 (95% CI, 0.599 to 0.772) for IDFS and 0.675 (95% CI, 0.588 to 0.774) for DRFS. This persistence of abemaciclib benefit translated to continuous separation of the curves with a deepening in 5-year absolute improvement in IDFS and DRFS rates of 7.6% and 6.7%, respectively, compared with rates of 6% and 5.3% at 4 years and 4.8% and 4.1% at 3 years. With fewer deaths in the abemaciclib plus ET arm compared with the ET-alone arm (208 v 234), statistical significance was not reached for OS. No new safety signals were observed. In conclusion, abemaciclib plus ET continued to reduce the risk of developing invasive and distant disease recurrence beyond the completion of treatment. The increasing absolute improvement at 5 years is consistent with a carryover effect and further supports the use of abemaciclib in patients with high-risk EBC.

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned coprimary or secondary analyses are not yet available. Clinical trial updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported. PALOMA-2 demonstrated statistically and clinically significant improvement in progression-free survival with palbociclib plus letrozole versus placebo plus letrozole in estrogen receptor-positive/human epidermal growth factor receptor 2-negative (ER+/HER2-) advanced breast cancer (ABC). Here, we report results for the secondary end point overall survival (OS). Postmenopausal women (N = 666) with ER+/HER2- ABC without previous systemic therapy for ABC were randomly assigned 2:1 to palbociclib plus letrozole or placebo plus letrozole. After a median follow-up of 90.1 months, 405 deaths were observed and 155 patients were known to be alive. The median OS was 53.9 months (95% CI, 49.8 to 60.8) with palbociclib plus letrozole versus 51.2 months (95% CI, 43.7 to 58.9) with placebo plus letrozole (hazard ratio [HR], 0.96 [95% CI, 0.78 to 1.18]; stratified one-sided P = .34). An imbalance in the number of patients with unknown survival outcome between the treatment arms (13.3% v 21.2%, respectively) limited interpretation of OS results. With recovered survival data, the median OS was 53.8 (95% CI, 49.8 to 59.2) versus 49.8 months (95% CI, 42.3 to 56.4), respectively (HR, 0.92 [95% CI, 0.76 to 1.12]; one-sided P = .21). OS was not significantly improved with palbociclib plus letrozole compared with placebo plus letrozole.

Background: In monarchE, abemaciclib demonstrated a sustained benefit in invasive disease-free survival and a tolerable safety profile at 42-months median follow-up. With no expected disease-related symptoms, therapies in the adjuvant setting should preserve quality of life (QoL). With all patients off abemaciclib, we report updated patient-reported outcomes (PROs) for the full 2-year treatment period and follow-up., Methods: Patients completed PROs including FACT-B, FACT-ES, and FACIT-Fatigue at baseline, 3, 6, 12, 18, and 24 months during treatment, and 1, 6, and 12 months after treatment discontinuation. Mixed effects repeated measures model estimated changes from baseline within and between arms for QoL scales and individual items. Meaningful changes were prespecified and no statistical testing was performed. Frequencies of responses to items associated with relevant adverse events and treatment bother were summarized., Results: At baseline, completion rates for PRO instruments were >96 %. Mean changes from baseline for all QoL scales were numerically similar within and between arms (ie, less than prespecified thresholds). The same was observed for all individual items, except diarrhea. Within abemaciclib arm, meaningful differences for diarrhea were observed at 3 and 6 months (mean increases of 1.19 and 1.03 points on 5-point scale, respectively). During treatment, most patients in both arms (69-78 %) reported being bothered "a little bit" or "not at all" by side effects. Overall, patterns for fatigue were similar between arms. During post-treatment follow-up, PROs in both arms were similar to baseline., Conclusion: PRO findings confirm a tolerable and reversible toxicity profile for abemaciclib. QoL was preserved with the addition of adjuvant abemaciclib to endocrine therapy, supporting its use in patients with HR+, HER2-, high-risk early breast cancer., Competing Interests: Declaration of Competing Interest SMT reports serving as a consulting or advisory role for Novartis, Pfizer, Merck, Eli Lilly and Company, AstraZeneca, Genentech/Roche, Eisai, Sanofi, Bristol Myers Squibb, Seattle Genetics, CytomX Therapeutics, Daiichi Sankyo, Gilead, OncXerna, Zymeworks, Zentalis, Blueprint Medicines, Reveal Genomics, ARC Therapeutics, Infinity Therapeutics, Myovant (now Sumitovant Biopharma), Zetagen, Umoja Biopharma, Artios Pharma, Menarini/Stemline, Aadi Biopharma, Bayer, Incyte Corp, Jazz Pharmaceuticals, Natera; and research funding (to institute) from Genentech/Roche, Merck, Exelixis, Pfizer, Eli Lilly and Company, Novartis, Bristol Myers Squibb, Eisai, AstraZeneca, NanoString Technologies, Gilead, Seattle Genetics, OncoPep, Daiichi Sankyo, outside of the submitted work. VG reports personal fees for advisory board membership for AstraZeneca, Daiichi Sankyo, Eisai, Eli Lilly and Company, Exact Sciences, Gilead, Merck Serono, MSD, Novartis, Pfizer, Olema Oncology, Pierre Fabre; personal fees as an invited speaker for AstraZeneca, Daiichi Sankyo, Eli Lilly and Company, Exact Sciences, Gilead, GSK Novartis and Zentiva; personal fees for expert testimony for Eli Lilly and Company, outside of the submitted work. JHS reports no known competing financial interest or personal relationships that could have appeared to influence the submitted work. JC reports honoraria from Glaxo, AstraZeneca, Roche, Novartis, Pharmamar, Eisai, Eli Lilly and Company, Daichii Sankyo, Gilead, Seagen, MSD, Pierre Fabre, and Pfizer; serves as a consulting or advisory role for AstraZeneca, Roche, Novartis, Pharmamar, Eisai, Eli Lilly and Company, Glaxo, Daichii Sankyo, Gilead, Seagen, Deciphera, and Pfizer; and travel expenses from Novartis, Gilead, Pharmamar, and Daichii-Sankyo, outside of the submitted work. MHA reports no known competing financial interest or personal relationships that could have appeared to influence the submitted work. MT reports fees from Eli Lilly and Company for speaker’s bureau, outside of the submitted work. CB reports grants and research support to their institution from Nektar, Pfizer, Polyphor, Amgen, Daiichi Sankyo, Sanofi, Exelixis, Regeneron, Novartis, GSK, Janssen, OBI Pharma, Eli Lilly and Company, Seagen, Roche, Bristol-Myers Squibb, MSD, Merck Serono, AstraZeneca, Novocure, Aveo Oncology, Takeda, TRIO, PharmaMar, Celgene, PPD, Syneos Health, Labcorp, ICON, IQVIA, Parexel, Nuvisan, PSI, Worldwide, Gilead Sciences, Bayer, and Servier; ownership or stocks from Tummi and MEDSIR; and serves on the advisory boards and consulting with Boehringer-Ingelheim, GSK, Novartis, Pfizer, Roche/Genentech, Eisai, Bayer, MSD, AstraZeneca, Zodiac, Eli Lilly and Company, Sanofi, and Daiichi, outside of the submitted work. KM reports no known competing financial interest or personal relationships that could have appeared to influence the submitted work. RW, MMunoz, BSA, AML are employees and/or stock shareholders of Eli Lilly and Company. MMartin reports research grants from Roche, PUMA and Novartis; consulting/advisory fees from AstraZeneca, Amgen, Taiho Oncology, Roche/Genentech, Novartis, PharmaMar, Eli Lilly and Company, PUMA, Taiho Oncology, Daiichi Sankyo, Menarini/Stemline, and Pfizer; speakers’ honoraria from AstraZeneca, Lilly, Amgen, Roche/Genentech, Novartis, and Pfizer, outside of the submitted work. SRDJ reports grants or contracts from Pfizer, Puma Biotechnology, Eli Lilly and Company, AstraZeneca, Novartis, and Roche–Genentech for research funding to institute for laboratory studies and clinical trials; consulting fees from Eli Lilly and Company, AstraZeneca, Puma Biotechnology, Pfizer, Novartis, and Sanofi Genzyme for consulting or an advisory role; and payment or honoraria from Pfizer, Eisai, AstraZeneca, and Roche–Genentech for speaker's bureau, outside of the submitted work. PKL reports no known competing financial interest or personal relationships that could have appeared to influence the submitted work. NH reports honoraria for lectures and/or consulting froom Amgen, AstraZeneca, Daiichi-Sankyo, EPG Communication, Gilead, Eli Lilly and Company, MEDSCAPE, MSD, Novartis, Pierre-Fabre, Pfizer, Roche, Sandoz, Sanofi, Seagen, Springer, Viatris, and Zuelligpharma; ownership interest in Minority ownership as Co-Director West German Study Group (WSG), outside of the submitted work., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: The HER2DX risk-score has undergone rigorous validation in prior investigations involving patients with early-stage human epidermal growth factor receptor 2 (HER2)-positive (HER2+) breast cancer. In this study, we present the outcomes of the HER2DX risk-score within the most recent release of the Sweden Cancerome Analysis Network-Breast (SCAN-B) HER2+ cohort. This updated examination benefits from a larger patient sample, an extended follow-up duration, and detailed treatment information., Materials and Methods: Clinical and RNAseq data from the SCAN-B dataset were retrieved from Gene Expression Omnibus (GSE81538). Among the 6600 patients, 819 had HER2+ breast cancer, with 757 individuals with research-based HER2DX risk-scores and corresponding survival outcomes. The HER2DX risk-score was evaluated (i) as a continuous variable and (ii) using predefined cut-offs. The primary endpoint for this study was overall survival (OS). The Kaplan-Meier method and Cox models were used to estimate OS and a multistate model with four states was fitted to better characterize patients' follow-up., Results: The median follow-up time was 7.5 years (n = 757). The most common systemic therapy was chemotherapy with trastuzumab (82.0%) and most tumors were classified as T1-T2 (97.1%). The HER2DX risk-score as a continuous variable was significantly associated with OS after adjustment for clinical variables and treatment regimen [hazard ratios (HR) per 10-unit increment = 1.31, 95% confidence interval (CI) 1.13-1.51, P < 0.001] as well as within predefined risk groups (high versus low; HR = 2.57, 95% CI 1.36-4.85, P < 0.001). Patients classified as HER2DX high-risk also had higher risk of (i) breast cancer recurrence and (ii) death without previous recurrence. Within the subgroup of HER2+ T1N0 tumors (n = 297), those classified as high-risk demonstrated inferior OS compared to low-risk tumors (7-year OS 77.8% versus 96.8%, P < 0.001). The HER2DX mRNA ERBB2 score was associated with clinical HER2 status (area under the receiver operating characteristic curve = 0.91)., Conclusions: In patients with early-stage HER2+ breast cancer, HER2DX risk-score provides prognostic information beyond clinicopathological variables, including treatment regimen with or without trastuzumab., Competing Interests: Role of the funder In addition to financial support, the funders actively contributed to various aspects of the research, including study design, data collection, analysis, interpretation, and report writing. Disclosure GV has received a speaker’s fee from MSD, Pfizer, GSK, and Pierre Fabre; has held an advisory role with AstraZeneca; and received consultant fees from Reveal Genomics. TP has received honoraria for speaker activities from AstraZeneca, Pfizer, Novartis, Veracyte, and Argenetics, and has held an advisory role with Novartis. FBM has a patent application (EP21383165). LP is listed as an inventor on patent PCT/EP2021/070788. OMS has declared travel expenses and consulting fees from Roche and Reveal, and speaker fees from Eisai, Daiichi-Sankyo, and Novartis. JC has ownership interests in MedSIR, Nektar, and Leuko; has held consulting or advisory roles in Celgene, Cellestia Biotech, AstraZeneca, Roche, Seattle Genetics, Daiichi-Sankyo, ERYTECH Pharma, Polyphor, Athenex, Lilly, Servier, Merck Sharp & Dohme, GlaxoSmithKline, Leuko, Clovis Oncology, Bioasis, Boehringer Ingelheim, Ellipses Pharma, HiberCell, Bioinvent, GEMoaB, Gilead Sciences, Menarini, Zymeworks, and Reveal Genomics; has received research funding from ARIAD, AstraZeneca, Baxalta, Bayer, Eisai, Guardant Health, Merck Sharp & Dohme, Pfizer, Puma Biotechnology, Queen Mary University of London, Roche, and Piqur; has patents, royalties, or other intellectual property from pharmaceutical combinations of a Pi3k Inhibitor and a microtubule destabilizing agent (Javier Cortés Castán, Alejandro Piris Giménez, Violeta Serra Elizalde. WO 2014/199294 A, Her2 as a predictor of response to dual HER2 blockade in the absence of cytotoxic therapy. Aleix Prat, Antonio Llombart, Javier Cortés. US 2019/ 0338368 A1); and has received travel expenses from Roche, Pfizer, Eisai, Novartis, Daiichi-Sankyo, and Gilead Sciences. EC has received honoraria for advisory roles from Pfizer, AstraZeneca, Daiichi-Sankyo, Roche, Novartis, Lilly, and MSD; and has received a speaker’s fee from Roche and Lilly. MM reports research grants from Puma; consulting/advisory fees from Roche, Novartis, AstraZeneca, Daiichi-Sankyo, Seagen, Lilly, and Sanofi; speakers’ honoraria from Seagen, Lilly, AstraZeneca, Pfizer, Daiichi-Sankyo, and Roche; a leadership or fiduciary role as Chairman, GEICAM and as a member of the Board of Directors for TRIO. PC reports speakers’ bureaus with AstraZeneca, GlaxoSmithKline, Novartis, and Roche; travel, accommodation, and expenses from Celgene, GlaxoSmithKline, and Novartis; and research funding from Merck Serono, Novartis, and Roche. LAC reports participation on a Data Safety Monitoring Board or Advisory Board of Sanofi Aventis, Novartis, Genentech/Roche, GSK, AstraZeneca/Daiichi-Sankyo, and Aptitude Health; and has a spouse serving on the board of Falcon Therapeutics and spouse involvement in a neural stem cell therapy patent. NH received consulting fees from Pierre Fabre and Roche. AV has the DNADX patent filed (EP22382387.3). GC served as consultant or advisor for Roche, Lilly, and Bristol-Myers Squibb; served on the speaker’s bureau for Roche, Pfizer, and Lilly; received travel funding from Pfizer and Roche; and received honoraria from Roche, Pfizer, Lilly, Novartis, and Seagen, all outside the submitted work. PV is one of the stockholders of Reveal Genomics, and also reports personal fees from NanoString. JSP is an equity stockholder and consultant for Reveal Genomics and is listed as an inventor on patent applications for the Breast PAM50 assay. CMP is an equity stockholder and consultant of BioClassifier LLC and Reveal Genomics, and is listed as an inventor on patent applications for the Breast PAM50 assay. AP reports advisory and consulting fees from Roche, Pfizer, Novartis, Amgen, Bristol-Myers Squibb, Puma, Oncolytics Biotech, MSD, Guardant Health, Peptomyc, and Lilly; lecture fees from Roche, Pfizer, Novartis, Amgen, Bristol-Myers Squibb, NanoString Technologies, and Daiichi-Sankyo; institutional financial interests from Boehringer, Novartis, Roche, NanoString, Sysmex Europa GmbH, Medica Scientia Innovation Research, SL, Celgene, Astellas, and Pfizer; is a stockholder and consultant of Reveal Genomics and SL; and is listed as an inventor on patent applications for the HER2DX assay. SMT reports consulting or advisory roles for Novartis, Pfizer, Merck, Eli Lilly, AstraZeneca, Genentech/Roche, Eisai, Sanofi, Bristol-Myers Squibb, Seattle Genetics, CytomX Therapeutics, Daiichi-Sankyo, Gilead, OncXerna, Zymeworks, Zentalis, Blueprint Medicines, Reveal Genomics, ARC Therapeutics, Infinity Therapeutics, Sumitovant Biopharma, Zetagen, Umoja Biopharma, Artios Pharma, Menarini/Stemline, Aadi Biopharma, Bayer, Incyte Corp, Jazz Pharmaceuticals, Natera, Tango Therapeutics, Systimmune, eFFECTOR, and Hengrui USA; research funding from Genentech/Roche, Merck, Exelixis, Pfizer, Lilly, Novartis, Bristol-Myers Squibb, Eisai, AstraZeneca, Gilead, NanoString Technologies, Seattle Genetics, and OncoPep; and travel support from Eli Lilly, Sanofi, Gilead, and Pfizer. All other authors have declared no conflicts of interest., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Novel systemic therapies for breast cancer are being rapidly implemented into clinical practice. These drugs often have different mechanisms of action and side-effect profiles compared with traditional chemotherapy. Underpinning practice-changing clinical trials focused on the systemic therapies under investigation, thus there are sparse data available on radiotherapy. Integration of these new systemic therapies with radiotherapy is therefore challenging. Given this rapid, transformative change in breast cancer multimodal management, the multidisciplinary community must unite to ensure optimal, safe, and equitable treatment for all patients. The aim of this collaborative group of radiation, clinical, and medical oncologists, basic and translational scientists, and patient advocates was to: scope, synthesise, and summarise the literature on integrating novel drugs with radiotherapy for breast cancer; produce consensus statements on drug-radiotherapy integration, where specific evidence is lacking; and make best-practice recommendations for recording of radiotherapy data and quality assurance for subsequent studies testing novel drugs., Competing Interests: Declaration of interests IMe declares participation in advisory boards supported by Eli Lilly, Novartis, Pfizer, Pierre Fabre, SeaGen, Daiichi Sankyo, and AstraZeneca. CB declares honoraria from Eli Lilly, and participation in advisory boards supported by Eli Lilly, Novartis, Pfizer, and Amgen. ML received honoraria from or participated in advisory boards for Roche, Novartis, Eli Lilly, Pfizer, AstraZeneca, Daiichi Sankyo, Gilead, SeaGen, Merck Sharp and Dohme, Exact Sciences, Takeda, Ipsen, Sandoz, Libbs, and Knight; received a travel grant from Gilead; and received research support for their institution from Gilead. EdA declares honoraria from or participation in advisory boards for Roche, Genentech, Novartis, SeaGen, Zodiac, Libbs, Pierre Fabre, Eli Lilly, and AstraZeneca. JC declares consulting or advisor roles supported by Roche, Celgene, Cellestia, AstraZeneca, SeaGen, Daiichi Sankyo, Erytech, Athenex, Polyphor, Eli Lilly, Merck Sharp and Dohme, GSK, Leuko, Bioasis, Clovis Oncology, Boehringer Ingelheim, Ellipses, Hibercell, BioInvent, Gemoab, Gilead, Menarini, Zymeworks, Reveal Genomics, and Expres2ion Biotechnologies. NH declares honoraria for lectures or consulting from AstraZeneca, Daiichi Sankyo, Gilead, Eli Lilly, Merck Sharp and Dohme, Novartis, Pierre Fabre, Pfizer, Roche, Sanofi, Sandoz, and SeaGen. HSR declares institutional research support from Astellas Pharma, AstraZeneca, Daiichi Sankyo, F Hoffmann-La Roche, Genentech, Gilead Sciences, GSK, Eli Lilly, Merck & Co, Novartis Pharmaceuticals Corporation, OBI Pharma, Pfizer, Pionyr Immunotherapeutics, Sermonix Pharmaceuticals, Taiho Oncology, and Veru. GC reports personal fees for consulting, advisory roles, and speakers’ bureau from Roche, Genentech, Novartis, Pfizer, Eli Lilly, Foundation Medicine, Samsung, and Daiichi Sankyo; honoraria from Ellipses Pharma; and fees for travel and accommodations from Roche, Genentech, and Pfizer. LV declares participation in advisory boards from Daiichi Sankyo and Pfizer. ME declares participation in advisory boards supported by Pfizer and Novartis, and lecture fees supported by AstraZeneca. TS declares participation in advisory boards supported by Bristol Myers Squibb, Merck Sharp and Dohme, Novartis, and Pierre Fabre; and lecture fees supported by Astellas, AstraZeneca, and Bristol Myers Squibb. GM declares consultancy honoraria from Roche, Novartis, AstraZeneca, Pfizer, Jensen, Eli Lilly, and Sanofi. LDM declares consulting fees from Roche, Novartis, Eli Lilly, Merck Sharp and Dohme, Daiichi Sankyo, SeaGen, Gilead, Eisai, Pierre Fabre, AstraZeneca, Stemline Menarini, Exact Sciences, Agendia, GSK, and Pfizer. MM declares consulting fees from Cedilla Therapeutics and PharmEnable, and research support from PharmaMar, Eli Lilly, Pfizer, and Circle Pharma. SP-S declares consulting fees from Pfizer, Novartis, Eli Lilly, AstraZeneca, Gilead, Merck, Sharp and Dohme, and Roche. BP declares consulting fees from Astra Zeneca, SeaGen, Gilead, Eli Lilly, Merck Sharp and Dohme, Daiichi Sankyo, and Pierre Fabre. CS declares consulting fees from AstraZeneca, Daiichi Sankyo, Eisai Europe, Gilead, Novartis, Pharmalex, Pfizer, Phillips Health Works, Pierre Fabre, PintPharma, Puma Biotechnology, Roche Farma, SeaGen, Solti, Synthon Biopharmaceuticals, and Zymeworks. All other authors declare no competing interests., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Introduction: Quality care in breast cancer is higher if patients are treated in a Breast Center with a dedicated and specialized multidisciplinary team. Quality control is an essential activity to ensure quality care, which has to be based on the monitoring of specific quality indicators. Eusoma has proceeded with the up-dating of the 2017 Quality indicators for non-metastatic breast cancer based on the new diagnostic, locoregional and systemic treatment modalities., Methods: To proceed with the updating, EUSOMA setup a multidisciplinary working group of BC experts and patients' representatives. It is a comprehensive set of QIs for early breast cancer care, which are classified as mandatory, recommended, or observational. For the first time patient reported outcomes (PROMs) have been included. As used in the 2017 EUSOMA QIs, evidence levels were based on the short version of the US Agency for Healthcare Research and Quality., Results: This is a set of quality indicators representative for the different steps of the patient pathway in non-metastatic setting, which allow Breast Centres to monitor their performance with referring standards, i.e minimum standard and target., Conclusions: Monitoring these Quality Indicators, within the Eusoma datacentre will allow to have a state of the art picture at European Breast Centres level and the development of challenging research projects., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests., (Copyright © 2024. Published by Elsevier Ltd.)

Introduction: The interdisciplinary empowerment seminar aims to familiarize patients and informal caregivers (ICs) with supportive measures, focusing on understanding disease, therapy, and side effect management., Methods: The seminar, conducted in two courses over 1-month intervals prior to chemotherapy, included lectures, supportive materials, Q and A sessions, and individual discussions with experts in nutrition, exercise, psycho-oncology, and complementary medicine. Evaluation is based on a self-developed questionnaire and questionnaires on QoL (EORTC-QLQ-C30, BR23, CX24, OV28), anxiety and depression (HADS-D) at week 0, 5, 9, and 12. A control group with standard of care was evaluated at baseline and after 12 weeks., Results: Between October 2020 and May 2021, 19 patients and 9 ICs participated in the seminar. The control group included 20 patients. 96.4% of participants were highly satisfied with the seminar and would recommend it. QoL deterioration was more pronounced in the control group (control: week 0 = 67.6; week 12 = 61.7; intervention: week 0 = 60.8; week 12 = 60.7). This trend could not be proven by analysis of interaction (mixed ANOVA: p = 0.114). Increased confidence of participants' knowledge about side effects was shown, and ICs reported higher confidence in knowledge and coping with the disease., Conclusions: The seminar received positive feedback and indicated increased knowledge and a trend toward better QoL preservation. Larger studies are needed for confirmation. The seminar effectively addressed unique needs, bolstering confidence and knowledge. Interdisciplinary patient and caregiver empowerment seminars can improve disease-related knowledge and positively affect QoL at the start of chemotherapy. Informational needs can be satisfied. Offering educational seminars and fostering individualized support networks can increase quality of care., (© 2024 S. Karger AG, Basel.)

Introduction: Breast cancer patients (BCP) experience considerable side effects during and after treatment. Several studies have shown positive effects of exercise on therapy-related side-effects such as loss of muscle strength, loss of bone mineral density, lymphedema, and several elements of quality of life (QoL). Resistance exercise has proven effective and beneficial for BCP; however, optimal individual training parameters remain to be determined., Methods: The aim of our study was to implement an adaptive, progressive, supervised resistance protocol for BCPs during chemotherapy, improving muscle strength, physical condition, and overall QoL while reducing therapy-induced side-effects. Forty patients receiving adjuvant chemotherapy were included 6-12 weeks post-OP. Twenty patients underwent high intensity resistance-training twice a week for 12 weeks, and the control group received usual care., Results: Strength parameters improved significantly in the intervention group and in different scales of QoL. We documented a cyclic performance level dependent on the number of days after treatment., Conclusion: Adaptive resistance training with simple training control mechanisms proved to be effective regarding optimal intensity in each training session and needs to be implemented in further studies in order to guarantee adequate loads in accordance to the training protocols., (© 2024 S. Karger AG, Basel.)

Background: Oral cancer medications offer advantages but also pose challenges for therapy management and adherence. An eHealth-based platform such as CANKADO can help to support therapy management by probing the patient's quality of life (QoL) continuously throughout the course of treatment., Material and Methods: AGO-B WSG PreCycle (NCT03220178) is a multicenter, randomized phase IV intergroup trial evaluating the impact of eHealth-based Patient-Reported Outcome (ePRO) assessment on QoL in patients with hormone receptor-positive (HR + )/HER2-negative (HER2-) advanced breast cancer treated with palbociclib and endocrine therapy. Patients were randomized (2:1) to CANKADO-active arm (supported by CANKADO PRO-React) or CANKADO-inform arm (drug intake documentation only) This exploratory analysis reports the impact of CANKADO PRO-React on safety. Time to first serious adverse event (SAE) was estimated taking competing risks into account., Results: While distributions of adverse events (AEs) were similar by arm overall, patients in the CANKADO-active arm had a favorable hazard ratio of 0.67 (95%CI 0.46-0.97; p = 0.04) for time to first SAE and were significantly less likely overall to suffer an SAE than patients in the inform arm. At 24 months, 22.9% [17.9%-27.8%] of patients in CANKADO-active had suffered an SAE vs. 30.3% [22.6%-38.0%] in CANKADO-inform. AE-related dose reductions affected approximately 20% of patients (CANKADO-active: 18.2%, CANKADO-inform: 21.1%)., Conclusion: Exploratory safety analysis of PreCycle demonstrates for the first time in a randomized prospective trial that interactive autonomous eHealth-based support has a substantial favorable impact on the risk of SAEs and mitigates their severity for patients with advanced HR+/HER2- breast cancer on oral tumor therapy., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: [NH reported support for the present manuscript (e.g., funding, provision of study materials, medical writing, article processing charges, etc.) from palleos healthcare; consulting fees from Gilead, Pfizer, Sanofi, Sandoz, Roche, Seagen; payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing or educational events from AstraZeneca, EPG Communication, Lilly, MSD, Pierre Fabre, Roche, Seagen, Viatris, Daiichi Sankyo, Gilead, MEDSCAPE, Novartis, Pfizer, Sanofi, Springer, Zuelligpharma; and co-director position at WSG – West German Study Group. REK reported consulting fees to an immediate family member from Roche/Genentech, Novartis, BMS, Pfizer, Lilly, Sandoz, Daiichi Sankyo, Agendia, AstraZeneca, Merck Sharp & Dohne, Ondonate Therapeutics, Sattle Genetics, and palleos healthcare; payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing or educational events to an immediate family member from Roche, Novartis, BMS, Amgen, Pfizer, Genomic Health, and NanoString Technologies. TS reported stock or stock options from CANKADO GmbH; other financial or non-financial interests from CANKADO GmbH. RW reported consulting fees, payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing or educational events as well as support for attending meetings and/or travel from Agendia, Aristo, BMS, Daiichi Sankyo, Exact Sciences, Glaxo Smith Kline, Lilly, MSD, Mylan, Novartis, Paxman, Pfizer, PINK, Sandoz/Hexal, Riemser, Seattle Genetics/Seagen, Tesaro Bio, Veracyte, Amgen, AstraZeneca, Clovis Oncology, Eisai, Gilead, Hexal, Medstrom Medical, Mundipharma, Nanostring, Ondonate, palleos healthcare, Perre Fabre, PumyBiotechnology, Roche, Sanofi Genzyme, Stemline, Teva, Viatris; other financial or non-financial interests from FOMF, Pomme Med, MCI, Aurikamed, medconcept and Breast Center, Department of Obstetrics and Gynecology and Comprehensive Center (CCC) Munich, LMU University Hospital, Munich Germany. DL reported consulting fees from AstraZeneca, Novartis, Daiichi Sankyo, Amgen, Loreal, High5md, Eli Lilly, Pfizer, Gilead, GSK, Onkowissen; honoraria from Astra Zeneca, Novartis, Daiichi Sankyo, Amgen, Loreal, High5md, Eli Lilly, Pfizer, Gilead, GSK, Onkowissen; payment for expert testimony from AstraZeneca, Novartis, Daiichi Sankyo, Amgen, Loreal, High5md, Eli Lilly, Pfizer, Gilead, GSK, Onkowissen; support for attending meetings and/or travel from AstraZeneca, Novartis, Daiichi Sankyo, Amgen, Loreal, High5md, Eli Lilly, Pfizer, Gilead, GSK, Onkowissen; Board or Advisory Board from AstraZeneca, Novartis, Daiichi Sankyo, Amgen, Loreal, High5md, Eli Lilly, Pfizer, Gilead, GSK, Onkowissen; leadership or fiduciary role in other board, society, committee or advocacy group, paid or unpaid from Deutsche Stiftung für junge Erwachsene mit Krebs. OH reported consulting fees, payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing or educational events as well as support for attending meetings and/or travel, and participation on a Data Safety Monitoring Board or Advisory Board from Roche, MSD, Gilead, Novartis, Lilly, Pfizer, AstraZeneca, Daiichi Sankyo, Seagen, Amgen, Eisai; from Roche, MSD, Gilead, Novartis, Lilly, Pfizer, AstraZeneca, Daiichi Sankyo, Seagen, Amgen, Eisai. TDecker reported personal fees from Adboards, Novartis and iOMEDICO. MR reported consulting fees from Roche, Daiichi Sankyo, Somatex; payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing or educational events from Roche, AstraZeneca, Novartis, Daiichi Sankyo, Gilead, Somatex, Pfizer, Lilly; support for attending meetings and/or travel from Novartis, Pfizer, Gilead and Astra Zeneca. PS reported honoraria from Abbvie, Amgen, AstraZeneca, BMS, MSD Oncology, Pfizer, Merck Serono, Roche, Novartis; consulting or advisory role from Abbvie, Amgen, AstraZeneca, BMS; speakers' bureau from Abbvie, Amgen, AstraZeneca, BMS, Roche, Pfizer; research funding from Abbvie, BMS, Novartis, Roche; travel, accommodations, expenses from Abbvie, AstraZeneca; other from Abbvie, Amgen, BMS, Eisai, Incyte, Ipsen, Gilead Sciences, AstraZeneca, Janssen Oncology, Lilly Medical, Merck Serono, MSD Oncology, Pfizer, Roche, Novartis, Takeda. OG reported consulting fees from Daiichi Sankyo, BMS, Genomic Health/Exact Sciences, Lilly, MSD, Novartis, Pfizer, Roche, Seagen, Pierre Fabre, Gilead, Molecular Health; honoraria from Genomic Health/Exact Sciences, Eisai, Roche, BMS, Pfizer, Novartis, NanoString Technologies, Agendia, AstraZeneca; travel support from Roche, Daiichi Sankyo, all outside of the submitted work; co-director position at West German Study Group (WSG). PAF reported personal fees for advisory board from Agendia, AstraZeneca, Daiichi Sankyo, Eisai, Hexal, Lilly, Merck, Sharp&Dohme, Novartis, Pfizer, Pierre Fabre, Roche, Sanofi Aventis, Seagen; personal fees for invited speaker from AstraZeneca, Daiichi Sankyo, Eisai, Gilead, Lilly, Merck, Sharp&Dohme, Novartis, Seagen; personal fees for medical writing support from Roche; non-financial support to the Institution from BioNTech, Cepheid; non-financial interests: member for Arbeitsgemeinschaft für Gynäkologische Onkologie, ASCO, Deutsche Gesellschaft für Senologie, Translational Research in Oncology. MS reported grants or contracts paid to the Institution from from AstraZeneca, BioNTech, Eisai, German Breast Group, Genentech, Novartis, Pantarhei Bioscience, Pfizer, Pierre Fabre, Roche; consulting fees from AstraZeneca, BioNTech, Eisai, Daiichi Sankyo, Lilly, MSD, Novartis, Pantarhei Bioscience, Pfizer, Pierre Fabre, Roche, Seagen; payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing or educational events from AstraZeneca, Novartis, Pfizer, Roche, Seagen; support for attending meetings and/or travel from Pfizer, Roche; patents planned, issued or pending EP 2951317 B1, EP 2390370 B1; participation on a Data Safety Monitoring Board or Advisory Board from AstraZeneca, BioNTech, Daiichi Sankyo, Eisai, Lilly, Novartis, Pantarhei Bioscience, Pfizer, Pierre Fabre, Roche and Seagen. All other authors have declared no conflicts of interest.]., (Copyright © 2023. Published by Elsevier Ltd.)

Background: Quality of life (QOL) is a critical factor in decision-making for advanced breast cancer (ABC). There is a need to improve how QOL and treatment-related side effects (SEs) that impact it are clinically assessed. We examined healthcare professionals' (HCPs') and patients' perspectives on the importance of QOL discussions and the impact of SEs on QOL in clinical settings., Patients and Methods: A cross-sectional online survey was conducted (7/2020-5/2021) among oncologists, nurses, and patients with HR+/HER2- ABC in 7 countries., Results: The survey was completed by 502 HCPs and 467 patients. Overall, 88% of oncologists and 49% of patients recalled QOL discussions at follow-up. In the first- through fourth-line (1L, 2L, 3L, and 4L) settings, respectively, 48%, 57%, 79%, and 85% of oncologists reported QOL was very important; 73% and 45% of patients receiving 1L and 2L treatment and 40% receiving 3L+ treatment indicated QOL was important. Patients reported that insomnia, anxiety, back pain, fatigue, diarrhea, hot flashes, low sexual interest, and loss of appetite had a moderate/severe impact on QOL. Of patients experiencing certain SEs, ≥64% did not discuss them with HCPs until there was a moderate/severe impact on QOL. In patients receiving a CDK4/6 inhibitor, SEs, including insomnia, diarrhea, back pain, and fatigue, had a moderate/severe impact on QOL., Conclusions: This survey discovered disconnects between HCPs and patients with ABC on the importance of QOL discussions and the impact of SEs on QOL. These data support the use of ABC-specific QOL questionnaires that closely monitor SEs impacting QOL., (© The Author(s) 2023. Published by Oxford University Press.)

Taselisib is a potent β-sparing phosphatidylinositol 3-kinase (PI3K) inhibitor that, with endocrine therapy, improves outcomes in phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA)-mutated (PIK3CAmut) advanced breast cancer. To understand alterations associated with response to PI3K inhibition, we analysed circulating tumour DNA (ctDNA) from participants enrolled in the SANDPIPER trial. Participants were designated as either PIK3CAmut or PIK3CA no mutation was detected (NMD) per baseline ctDNA. The top mutated genes and tumour fraction estimates identified were analysed for their association with outcomes. In participants with PIK3CAmut ctDNA treated with taselisib + fulvestrant, tumour protein p53 (TP53; encoding p53) and fibroblast growth factor receptor 1 (FGFR1) alterations were associated with shorter progression-free survival (PFS) compared to participants with NMD in these genes. Conversely, participants with PIK3CAmut ctDNA harbouring a neurofibromin 1 (NF1) alteration or high baseline tumour fraction estimate experienced improved PFS upon treatment with taselisib + fulvestrant compared to placebo + fulvestrant. Broadly, alterations in oestrogen receptor (ER), PI3K and p53 pathway genes were associated with resistance to taselisib + fulvestrant in participants with PIK3CAmut ctDNA. Altogether, we demonstrated the impact of genomic (co-)alterations on outcomes with one of the largest clinico-genomic datasets of ER+, HER2-, PIK3CAmut breast cancer patients treated with a PI3K inhibitor., (© 2023 Genentech, Inc and The Authors. Molecular Oncology published by John Wiley & Sons Ltd on behalf of Federation of European Biochemical Societies.)

Purpose: The Standardized Definitions for Efficacy End Points (STEEP) criteria, established in 2007 and updated in 2021 (STEEP 2.0), provide standardized definitions of adjuvant breast cancer (BC) end points. STEEP 2.0 identified a need to separately address end points for neoadjuvant clinical trials. The multidisciplinary NeoSTEEP working group of experts was convened to critically evaluate and align neoadjuvant BC trial end points., Methods: The NeoSTEEP working group concentrated on neoadjuvant systemic therapy end points in clinical trials with efficacy outcomes-both pathologic and time-to-event survival end points-particularly for registrational intent. Special considerations for subtypes and therapeutic approaches, imaging, nodal staging at surgery, bilateral and multifocal diseases, correlative tissue collection, and US Food and Drug Administration regulatory considerations were contemplated., Results: The working group recommends a preferred definition of pathologic complete response (pCR) as the absence of residual invasive cancer in the complete resected breast specimen and all sampled regional lymph nodes (ypT0/Tis ypN0 per AJCC staging). Residual cancer burden should be a secondary end point to facilitate future assessment of its utility. Alternative end points are needed for hormone receptor-positive disease. Time-to-event survival end point definitions should pay particular attention to the measurement starting point. Trials should include end points originating at random assignment (event-free survival and overall survival) to capture presurgery progression and deaths as events. Secondary end points adapted from STEEP 2.0, which are defined from starting at curative-intent surgery, may also be appropriate. Specification and standardization of biopsy protocols, imaging, and pathologic nodal evaluation are also crucial., Conclusion: End points in addition to pCR should be selected on the basis of clinical and biologic aspects of the tumor and the therapeutic agent investigated. Consistent prespecified definitions and interventions are paramount for clinically meaningful trial results and cross-trial comparison.

The cyclin-dependent kinase 4 and 6 inhibitors (CDK4/6i) have become the standard of care for hormone receptor-positive (HR + ) and human epidermal growth factor receptor 2-negative (HER2-) metastatic breast cancer, improving survival outcomes compared to endocrine therapy alone. Abemaciclib and ribociclib, in combination with endocrine therapy, have demonstrated significant benefits in invasive disease-free survival for high-risk HR+/HER2- early breast cancer patients. Each CDK4/6i-palbociclib, ribociclib, and abemaciclib-exhibits distinct toxicity profiles. Radiation therapy (RT) can be delivered with a palliative or ablative intent, particularly using stereotactic body radiation therapy for oligometastatic or oligoprogressive disease. However, pivotal randomized trials lack information on concomitant CDK4/6i and RT, and existing preclinical and clinical data on the potential combined toxicities are limited and conflicting. As part of a broader effort to establish international consensus recommendations for integrating RT and targeted agents in breast cancer treatment, we conducted a systematic review and meta-analysis to evaluate the safety profile of combining CDK4/6i with palliative and ablative RT in both metastatic and early breast cancer settings., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Background and Purpose: In recent years, the treatment landscape for breast cancer has undergone significant advancements, with the introduction of several new anticancer agents. One such agent is trastuzumab emtansine (T-DM1), an antibody drug conjugate that has shown improved outcomes in both early and advanced breast cancer. However, there is currently a lack of comprehensive evidence regarding the safety profile of combining T-DM1 with radiation therapy (RT). In this study, we aim to provide a summary of the available data on the safety of combining RT with T-DM1 in both early and metastatic breast cancer settings., Materials and Methods: This systematic review and meta-analysis project is part of the consensus recommendations by the European Society for Radiotherapy and Oncology (ESTRO) Guidelines Committee on integrating RT with targeted treatments for breast cancer. A thorough literature search was conducted using the PUBMED/MedLine, Embase, and Cochrane databases to identify original studies focusing on the safety profile of combining T-DM1 with RT., Results: After applying eligibility criteria, nine articles were included in the meta-analysis. Pooled data from these studies revealed a high incidence of grade 3 + radionecrosis (17%), while the rates of grade 3 + radiation-related pneumonitis (<1%) and skin toxicity (1%) were found to be very low., Conclusion: Although there is some concern regarding a slight increase in pneumonitis when combining T-DM1 with postoperative RT, the safety profile of this combination was deemed acceptable for locoregional treatment in non-metastatic breast cancer. However, caution is advised when irradiating intracranial sites concurrently with T-DM1. There is a pressing need for international consensus guidelines regarding the safety considerations of combining T-DM1 and RT for breast cancer., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Author(s). Published by Elsevier B.V. All rights reserved.)

Background: The multicenter, randomized, phase IV, intergroup AGO-B WSG PreCycle trial (NCT03220178) evaluated the impact of CANKADO-based electronic patient-reported outcome (ePRO) assessment on quality of life (QoL) in hormone receptor-positive, human epidermal growth factor receptor 2-negative locally advanced or metastatic breast cancer (MBC) patients receiving palbociclib and an aromatase inhibitor or palbociclib + fulvestrant. CANKADO PRO-React, a European Union-registered medical device, is an interactive autonomous application reacting to patient self-reported observations., Patients and Methods: Between 2017 and 2021, 499 patients (median age 59 years) from 71 centers were randomized (2 : 1, stratified by therapy line) between an active version of CANKADO PRO-React (CANKADO-active arm) and a version with limited functionality (CANKADO-inform arm). A total of 412 patients (271 CANKADO-active; 141 CANKADO-inform) were available for analysis of the primary endpoint, time to deterioration (TTD) of QoL [10-point drop on the Functional Assessment of Cancer Therapy-General (FACT-G) score], using an Aalen-Johansen estimator for cumulative incidence function of TTD DQoL (QoL deterioration) with 95% pointwise confidence intervals (CIs). Secondary endpoints included progression-free survival (PFS), overall survival (OS), and DQoL., Results: In all patients [intention-to-treat (ITT)-ePRO], cumulative incidence of DQoL was significantly more favorable (lower) in the CANKADO-active arm (hazard ratio 0.698, 95% CI 0.506-0.963). Among first-line patients (n = 295), the corresponding hazard ratio was 0.716 (0.484-1.060; P = 0.09), and in second-line patients (n = 117) it was 0.661 (0.374-1.168; P = 0.2). Absolute patient numbers declined in later visits; FACT-G completion rates were 80% and higher until about visit 30. Mean FACT-G scores showed a steady decline from baseline and an offset in favor of CANKADO-active. No significant differences in clinical outcome were observed between arms: median PFS (ITT population) was 21.4 (95% CI 19.4-23.7) (CANKADO-active) and 18.7 (15.1-23.5) months (CANKADO-inform); median OS was not reached (CANKADO-active) and 42.6 months (CANKADO-inform)., Conclusions: PreCycle is the first multicenter randomized eHealth trial demonstrating a significant benefit for MBC patients receiving oral tumor therapy when using an interactive autonomous patient empowerment application., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Purpose: Neoadjuvant chemotherapy is standard of care in human epidermal growth factor receptor 2-positive (HER2+) early breast cancer (EBC), irrespective of the hormone receptor status. Trastuzumab-emtansine (T-DM1), antibody-drug conjugate, is highly effective in HER2+ EBC; however, no survival data are available for de-escalated antibody-drug conjugate-based neoadjuvant therapy without conventional chemotherapy., Patients and Methods: In the WSG-ADAPT-TP (ClinicalTrials.gov identifier: NCT01779206) phase II trial, 375 centrally reviewed patients with hormone receptor-positive (HR+)/HER2+ EBC (clinical stage I-III) were randomly assigned to 12 weeks of T-DM1 with or without endocrine therapy (ET) or trastuzumab + ET once every 3 weeks (ratio 1:1:1). Adjuvant chemotherapy (ACT) omission was allowed in patients with pathologic complete response (pCR). In this study, we report the secondary survival end points and biomarker analysis. Patients who received at least one dose of study treatment were analyzed. Survival was analyzed using the Kaplan-Meier method, two-sided log-rank statistics, and Cox regression models stratified for nodal and menopausal status. P values < .05 were considered statistically significant., Results: T-DM1, T-DM1 + ET, and trastuzumab + ET induced similar 5-year invasive disease-free survival (iDFS; 88.9%, 85.3%, 84.6%; P log-rank = .608) and overall survival rates (97.2%, 96.4%, 96.3%; P log-rank = .534). Patients with pCR versus non-pCR had improved 5-year iDFS rates (92.7% v 82.7%; hazard ratio, 0.40 [95% CI, 0.18 to 0.85]). Among the 117 patients with pCR, 41 did not receive ACT; 5-year iDFS rates were similar in those with (93.0% [95% CI, 84.0 to 97.0]) and without ACT (92.1% [95% CI, 77.5 to 97.4]; P log-rank = .848). Translational research revealed that tumors with PIK3CA wild type, high immune marker expression, and luminal-A tumors (by PAM50) had an excellent prognosis with de-escalated anti-HER2 therapy., Conclusion: The WSG-ADAPT-TP trial demonstrated that pCR after 12 weeks of chemotherapy-free de-escalated neoadjuvant therapy was associated with excellent survival in HR+/HER2+ EBC without further ACT. Despite higher pCR rates for T-DM1 ± ET versus trastuzumab + ET, all trial arms had similar outcomes because of mandatory standard chemotherapy after non-pCR. WSG-ADAPT-TP demonstrated that such de-escalation trials in HER2+ EBC are feasible and safe for patients. Patient selection on the basis of biomarkers or molecular subtypes may increase the efficacy of systemic chemotherapy-free HER2-targeted approaches.

Introduction: [ 18 F]Fluoroestradiol ([ 18 F]FES) PET/CT has been proposed as a tool for detecting the oestrogen receptor density in patients with metastatic breast cancer (BC) non-invasively across all disease localizations. However, its diagnostic potential in terms of the detection rate (DR) of metastases is unclear. In this study, we pitted this method against [ 18 F]FDG PET/CT and tried to identify predictors of the diagnostic superiority of the [ 18 F] FES-based method., Materials and Methods: From a multicentre database, we enrolled all patients with metastatic BC who had undergone both [ 18 F]FES PET/CT and [ 18 F]FDG PET/CT. Two readers assessed both images independently and used a patient-based (PBA) and lesion-based analysis (LBA) to calculate the DR. Pathology-related and clinical factors were tested as predictors of [ 18 F]FES PET/CT superiority using a multivariate model., Results: 92 patients, bearing a total of 2678 metastases, were enrolled. On PBA, the DR of [ 18 F]FDG and [ 18 F]FES PET/CT was 97% and 86%, respectively (p = 0.018). On LBA, the [ 18 F]FES method proved more sensitive than [ 18 F]FDG PET/CT in lymph nodes, bone, lung and soft tissue (p < 0.01). This greater sensitivity was associated with lobular histology, both on PBA (Odds Ratio (OR) 3.4, 95%CI 1.0-12.3) and on LBA (OR 4.4, 95%CI 1.2-16.1 for lymph node metastases and OR 3.29, 95%CI 1.1-10.2 for bone localizations)., Conclusions: The overall DR of [ 18 F]FES PET/CT appears to be lower than that of [ 18 F]FDG PET/CT on PBA. However, the [ 18 F]FES method, if positive, can identify more lesions than [ 18 F]FDG at most sites. The higher sensitivity of [ 18 F]FES PET/CT was associated with lobular histology., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Importance: Combination of chemotherapy with (dual) ERBB2 blockade is considered standard in hormone receptor (HR)-positive/ERBB2-positive early breast cancer (EBC). Despite some promising data on endocrine therapy (ET) combination with dual ERBB2 blockade in HR-positive/ERBB2-positive BC, to our knowledge, no prospective comparison of neoadjuvant chemotherapy vs ET plus ERBB2 blockade in particular with focus on molecular markers has yet been performed., Objective: To determine whether neoadjuvant de-escalated chemotherapy is superior to endocrine therapy, both in combination with pertuzumab and trastuzumab, in a highly heterogeneous HR-positive/ERBB2-positive EBC., Design, Setting, and Participants: This prospective, multicenter, neoadjuvant randomized clinical trial allocated 207 patients with centrally confirmed estrogen receptor-positive and/or progesterone receptor-positive (>1%) HR-positive/ERBB2-positive EBC to 12 weeks of standard ET (n = 100) vs paclitaxel (n = 107) plus trastuzumab and pertuzumab. A total of 186 patients were required to detect a statistically significant difference in pathological complete response (pCR) (assumptions: 19% absolute difference in pCR; power, ≥80%; 1-sided Fisher exact test, 2.5% significance level)., Interventions: Standard ET (aromatase inhibitor or tamoxifen) or paclitaxel, 80 mg/m2, weekly plus trastuzumab and pertuzumab every 21 days., Main Outcomes and Measures: The primary end point was pCR (ypT0/is, ypN0). Secondary end points included safety, translational research, and health-related quality of life. Omission of further chemotherapy was allowed in patients with pCR. PAM50 analysis was performed on baseline tumor biopsies., Results: Of the 207 patients included (median [range] age, 53 [25-83] years), 121 (58%) had cT2 to cT4 tumors, and 58 (28%) had clinically node-positive EBC. The pCR rate in the ET plus trastuzumab and pertuzumab arm was 23.7% (95% CI, 15.7%-33.4%) vs 56.4% (95% CI, 46.2%-66.3%) in the paclitaxel plus trastuzumab and pertuzumab arm (odds ratio, 0.24; 95% CI, 0.12-0.46; P < .001). Both immunohistochemical ERBB2 score of 3 or higher and ERBB2-enriched subtype were independent predictors for pCR in both arms. Paclitaxel was superior to ET only in the first through third quartiles but not in the highest ERBB2 quartile by messenger RNA. In contrast with the paclitaxel plus trastuzumab and pertuzumab arm, no decrease in health-related quality of life after 12 weeks was observed in the ET plus trastuzumab and pertuzumab arm., Conclusions and Relevance: The WSG-TP-II randomized clinical trial is, to our knowledge, the first prospective trial comparing 2 neoadjuvant de-escalation treatments in HR-positive/ERBB2-positive EBC and demonstrated an excellent pCR rate after 12 weeks of paclitaxel plus trastuzumab and pertuzumab that was clearly superior to the pCR rate after ET plus trastuzumab and pertuzumab., Trial Registration: ClinicalTrials.gov Identifier: NCT03272477.

The most recent version of the European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, staging and treatment of patients with metastatic breast cancer (MBC) was published in 2021. A special, hybrid guidelines meeting was convened by ESMO and the Korean Society of Medical Oncology (KSMO) in collaboration with nine other Asian national oncology societies in May 2022 in order to adapt the ESMO 2021 guidelines to take into account the differences associated with the treatment of MBC in Asia. These guidelines represent the consensus opinions reached by a panel of Asian experts in the treatment of patients with MBC representing the oncological societies of China (CSCO), India (ISMPO), Indonesia (ISHMO), Japan (JSMO), Korea (KSMO), Malaysia (MOS), the Philippines (PSMO), Singapore (SSO), Taiwan (TOS) and Thailand (TSCO). The voting was based on the best available scientific evidence and was independent of drug access or practice restrictions in the different Asian countries. The latter were discussed when appropriate. The aim of these guidelines is to provide guidance for the harmonisation of the management of patients with MBC across the different regions of Asia, drawing from data provided by global and Asian trials whilst at the same time integrating the differences in genetics, demographics and scientific evidence, together with restricted access to certain therapeutic strategies., Competing Interests: Disclosure MLTAT declares consulting fees and honoraria from MSD, Roche, Novartis, Eli Lilly and AstraZeneca. HKA declares consulting fees from Daiichi Sankyo, Amgen, Yuhan and Novartis, and honoraria from Roche, BMS, MSD, Eli Lilly, AstraZeneca, Boehringer Ingelheim, Menarini, Eisai, Pfizer, Boryung Pharmaceutical Company, Celtrion, Pharmobio Korea Inc. and Yuhan. GC has served as consultant or advisor for Roche, Eli Lilly and BMS; served on a speaker’s bureau for Roche, Pfizer and Eli Lilly; received travel funding from Pfizer and Roche; and received honoraria from Roche, Pfizer, Eli Lilly, Novartis, AstraZeneca and SeaGen, all outside the submitted work. THF declares honoraria from AstraZeneca Oncology Indonesia, Takeda Indonesia, Eisai Indonesia, Roche Oncology Indonesia, J & J Indonesia and Zueling Pharma Indonesia and role as head of division of Area Development for West Java, Indonesia for the Indonesian Society of Hematology and Medical Oncology. AG declares honoraria for advisory boards from AstraZeneca, Daiichi Sankyo, Eisai, Eli Lilly, Novartis, Pfizer and Roche; honoraria for lectures from Eisai and Eli Lilly and honoraria for expert testimony from Gentili. SG declares honoraria from Lupin, Roche, Novartis, Eli Lilly, Eisai, Cipla, CADILA, Intas and AstraZeneca; honoraria for being on committees of the Indian Council of Medical Research (Government of India), Council of Scientific and Industrial Research (Government of India), Department of Biotechnology (Government of India), India Alliance and institutional; honoraria from Novartis and AstraZeneca for participation in steering committees; leadership roles include President of Indian Society of Medical and Paediatric Oncology and General Secretary of Women’s Cancer Initiative - Tata Memorial Hospital, both roles unpaid. NH reports honoraria for lectures, advisory boards and/or personal fees from Amgen, AstraZeneca, Daiichi Sankyo, Eli Lilly, MSD, Novartis, Pfizer, Pierre Fabre, Roche, Sandoz and SeaGen, and minority ownership interest in the West German Study Group. RAH declares honoraria from Roche, Novartis, MSD, Pfizer and Mylan, and support for attending meetings from Roche, MSD and Kalbe Pharma. SAI declares an institutional grant from AstraZeneca, Boryung Pharm, Daewoong Pharm, Eisai, Roche and Pfizer, and honoraria from AstraZeneca, Novartis, MSD, Roche, Pfizer; advisory role for AstraZeneca, Bertis, Daiichi Sankyo, Eisai, Hanmi, Lilly, MSD, Novartis, Roche and Pfizer. JHK declares an institutional grant from Ono Pharma Ltd., and honoraria from Novartis, MSD, Roche Pharma, Roche diagnostics, Pfizer, AstraZeneca, Eisai, Lilly, and Sanofi; fees for participation in data monitoring or advisory boards from Bixink, Eisai, Yuhan, Novartis, Daiichi Sankyo, Pfizer, Roche Pharma and Everest Medicines; institutional gifts from Eisai and Ono Pharma Ltd. SBK declares institutional funding from Novartis, Sanofi-Aventis and Dongkook Pharm Co.; consulting fees from Novartis, AstraZeneca, Lilly, DaeHwa Pharmaceutical Co Ltd., ISU Abxis, Beigene, OBI Pharma and Daiichi Sankyo; honoraria from Novartis, Pfizer, Lilly, OBI Pharma and Legochem Bioscience; participation on data safety monitoring or advisory boards for Novartis, AstraZeneca, MSD, Lilly and Daiichi Sankyo, and purchased stock in Genopeaks and Neogene TC. KHL declares honoraria from Pfizer, Novartis and Eli Lilly. SCL declares grants from Pfizer, Eisai, Taiho, ACT Genomics, MSD, Adagene and Epizyme; honoraria from Pfizer, Novartis, AstraZeneca, ACT Genomics, Eli Lilly, MSD and Roche and participation in data monitoring or advisory boards for Pfizer, Novartis, Eisai, Sanofi, Daiichi Sankyo, MSD and Roche. MYM declares institutional grants from MSD, Astella, Pfizer, Novartis, AstraZeneca, ARCUS, Amgen and honoraria from MSD, Amgen, Pfizer, Roche, Novartis, Zuelling Pharma, Specialised therapeutics, Eisai, GSK, Mundi Pharma, Eli Lilly and AstraZeneca. YN declares institutional grants from the Ministry of Health, Labour and Welfare, Abbvie, Ono, Daiichi Sankyo, Taiho, Pfizer, Boehringer Ingelheim, Eli Lilly, Eisai, AstraZeneca, Chugai, Bayer and honoraria from AstraZeneca, Eisai, Ono, Gardant, Takeda, Eli Lilly, Novartis, Pfizer, Chugai, Fuji Film Toyama Chemistry, Taiho, Mundi, Bristol, Shionogi. NP declares honoraria from AstraZeneca, Eisai, Roche, Eli Lilly, Novartis, Pfizer and MSD. YHP declares grants from AstraZeneca, Pfizer, Novartis, Roche and Gencurix, consulting fees from AstraZeneca, Pfizer, Novartis, Roche, Eisai, Daiichi Sankyo, MSD and Lilly, honoraria from Pfizer, MSD, Novartis and Roche, and participation on data monitoring boards and advisory boards for Roche, Eisai, Daiichi Sankyo, AstraZeneca, MSD and Novartis. SP declares fees for consultancy/advisory roles from Abbvie, Amgen, Arcus, AstraZeneca, Bayer, Beigene, Bio Invent, Biocartis, Blueprint Medicines, Boehringer Ingelheim, BMS, Daiichi Sankyo, Debiopharm, ecancer, Eli Lilly, Elsevier, F-star, Foundation Medicine, Genzyme, Gilhead, GSK, Illumina, Incyte, IQIVIA, iTHeos, Janssen, Medscape, MSD, Merck Serono, Mirati, Novartis, Novocure, Pharma Mar, Phosplatin Therapeutics, Pfizer, Regeneron, Roche/Genentech, Sanofi, SeaGen, Takeda, Vaccibody, speaker roles for AstraZeneca, Boehringer Ingelheim, BMS, ecancer, Eli Lilly, Fishawack, Illumina, Imedex, Medscape, Mirati MSD, Novartis, OncologyEducation, PER, Pfizer, PRIME, RMEI, Roche/Genentech, RTP, Sanofi, Takeda and steering committee and trial chair roles as follows: AstraZeneca, coordinating PI, institutional, no financial interest, MERMAID-1; AstraZeneca, steering committee member, institutional, no financial interest, MERMAID-2, POSEIDON, MYSTIC; Beigene, steering committee member, institutional, no financial interest, BGB-A317-A1217-301/AdvanTIG-301; BMS, steering committee member, institutional, no financial interest, clinical trial steering committee CheckMate 743, CheckMate 73L, CheckMate 331 and 451; BMS, steering committee member, institutional, no financial interest, RELATIVITY 095; GSK, trial chair, institutional, no financial interest, clinical trial chair ZEAL-1; iTeos, steering committee member, institutional, no financial interest, Phase 2 Inupadenant with chemo; Mirati, steering committee member, institutional, no financial interest, clinical trial steering committee SAPPHIRE; MSD, steering committee member, institutional, no financial interest, clinical trial steering committee PEARLS, MK-7684A; Pharma Mar, steering committee member, institutional, no financial interest, LAGOON; Phosplatin Therapeutics, steering committee member, institutional, no financial interest, phase 1/2 trials; Roche/Genentech, trial chair, institutional, no financial interest, clinical trial chair Skyscraper-01; chair ALEX; steering committee BFAST; steering committee BEAT-Meso; steering committee ImPower-030, IMforte. Also role as ESMO president, ETOP/EORTC/SAKK PI, involved in academic trials, ETOP/IBCSG partners officer. Council member and scientific chair, SAKK, vice-President Lung Group, SAMO, Vice President. BKS declares honoraria from Novartis and Eli Lilly. MS declares honoraria from AstraZeneca, MSD, Accord Health and Novartis, support for attending meetings from the Malaysia Urology Association and roles as an ex-committee member of the Malaysian Oncological Society and chairman of the Annual Scientific congress of the Malaysian Oncological Society. KT declares grants from Pfizer, Daiichi Sankyo, Eli Lilly, AstraZeneca, Eisai; honoraria from Daiichi Sankyo, Eli Lilly, Chugai, MSD; and data monitoring or advisory board fees from Daiichi Sankyo. SSW declares a grant from Pfizer and honoraria from Pfizer, Roche, AstraZeneca, Novartis, Daiichi Sankyo, Eli Lilly, MSD and Henrui. TY declares institutional grants from Amgen, Boehringer Ingelheim, Chugai, Daiichi Sankyo, Genomedia, MSD, Ono, Pfizer, Sanofi, Sysmex and Taiho, and honoraria Bayer, Chugai, Merck biopharma, MSD and Ono. All other authors have declared no conflicts of interest., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: In high-risk hormone receptor-positive/human epidermal growth factor receptor 2-negative (HR+/HER2-) early breast cancer (EBC), nanoparticle albumin-bound (nab)-paclitaxel showed promising efficacy versus solvent-based (sb)-paclitaxel in neoadjuvant trials; however, optimal patient and therapy selection remains a topic of ongoing research. Here, we investigate the potential of Oncotype DX® recurrence score (RS) and endocrine therapy (ET) response (low post-endocrine Ki67) for therapy selection., Patients and Methods: Within the WSG-ADAPT trial (NCT01779206), high-risk HR+/HER2- EBC patients were randomized to (neo)adjuvant 4× sb-paclitaxel 175 mg/m 2 q2w or 8× nab-paclitaxel 125 mg/m 2 q1w, followed by 4× epirubicin + cyclophosphamide (90 mg + 600 mg) q2w; inclusion criteria: (i) cN0-1, RS 12-25, and post-ET Ki67 >10%; (ii) cN0-1 with RS >25. Patients with cN2-3 or (G3, baseline Ki67 ≥40%, and tumor size >1 cm) were allowed to be included without RS and/or ET response testing. Associations of key factors with pathological complete response (pCR) (primary) and survival (secondary) endpoints were analyzed using statistical mediation and moderation models., Results: Eight hundred and sixty-four patients received neoadjuvant nab-paclitaxel (n= 437) or sb-paclitaxel (n = 427); nab-paclitaxel was superior for pCR (20.8% versus 12.9%, P = 0.002). pCR was higher for RS >25 versus RS ≤25 (16.0% versus 8.4%, P = 0.021) and for ET non-response versus ET response (15.1% versus 6.0%, P = 0.027); no factors were predictive for the relative efficacy of nab-paclitaxel versus sb-paclitaxel. Patients with pCR had longer distant disease-free survival [dDFS; hazard ratio 0.42, 95% confidence interval (CI) 0.20-0.91, P = 0.024]. Despite favorable prognostic association of RS >25 versus RS ≤25 with pCR (odds ratio 3.11, 95% CI 1.71-5.63, P ≤ 0.001), higher RS was unfavorably associated with dDFS (hazard ratio 1.03, 95% CI 1.01-1.05, P = 0.010)., Conclusions: In high-risk HR+/HER2- EBC, neoadjuvant nab-paclitaxel q1w appears superior to sb-paclitaxel q2w regarding pCR. Combining RS and ET response assessment appears to select patients with highest pCR rates. The disadvantage of higher RS for dDFS is reduced in patients with pCR. These are the first results from a large neoadjuvant randomized trial supporting the use of RS to help select patients for neoadjuvant chemotherapy in high-risk HR+/HER2- EBC., Competing Interests: Disclosure OG received consulting fees from Celgene, Genomic Health/Exact Sciences, Lilly, MSD, Novartis, Pfizer, Roche, Seagen, Pierre Fabre, Gilead, and Molecular health; honoraria from Genomic Health/Exact Sciences, Roche, Celgene, Pfizer, Novartis, NanoString Technologies, and AstraZeneca; payment for expert testimony from Genomic Health; and travel support from Roche, all outside of the submitted work; and co-director position at West German Study Group. SK received research funding from Roche and Novartis; consulting fees from Amgen, AstraZeneca, Celgene, Daiichi-Sankyo, Genomic Health/Exact Science, Lilly, MSD, Novartis, Seagen, Pfizer, pfm Medical, Roche, Somatex, and Gilead; travel support from Roche and Daiichi Sankyo; and other financial or non-financial interests for Non-Continuing Medical Education services from Somatex, Roche, Novartis, and Lilly, all outside of the submitted work; and co-director position at West German Study Group. UN received research funding paid to institution from Agendia, Amgen, Celgene, Genomic Health, NanoString Technologies, Roche, and Sanofi; consulting fees from Genomic Health and Roche; honoraria from Agendia, Amgen, Celgene, Genomic Health, NanoString Technologies, Novartis pharma, Pfizer Pharmaceuticals, Roche/Genentech, and Teva; payment for expert testimony from Genomic Health; travel support from Genomic Health, Pfizer Pharmaceuticals, and Roche; participation on a Data Safety Monitoring Board or Advisory Board at Roche, Seagen, and Exact Sciences, all outside of the submitted work; and co-director position at West German Study Group. MB received honoraria from AstraZeneca, Exact Sciences, Novartis, Pfizer, Roche, Teva, MSD; travel support from AstraZeneca, Celgene, Medac, Novartis, Roche, Daiichi Sankyo; and reports consulting/advisory role for AstraZeneca, Exact Sciences, Novartis, Puma, Roche, all outside of the submitted work. HF received honoraria from Roche and iOMEDICO (lecture); and travel support from Celgene and Amgen, all outside of the submitted work. CU received consulting fees from Tesaro, Novartis, Roche; research funding paid to institution from West German Study Group, German Breast Group, Novartis, AstraZeneca, Tesaro, Palleos Healthcare Services Gmbh, Pierre Fabre, AGO-Studiengruppe; travel support from German Breast Group, West German Study Group, AGO-Studiengruppe; and provided expert testimony for Pfizer, Novartis, Roche, PharmaMar, AstraZeneca, all outside of the submitted work. BA received honoraria from Pfizer, Roche Pharma, MSD, onkowissen.de, Novartis Pharma, AstraZeneca, PharmaMar, Lilly, promedicis, all outside of the submitted work. RK received consulting fees from AstraZeneca, Daiichi Sankyo, Lilly, MSD, Novartis, Pierre Fabre, Pfizer Pharmaceuticals, Roche/Genentech, Sandoz, and Seattle Genetics; and honoraria from Amgen, AstraZeneca, Genomic Health, Novartis, Pfizer Pharmaceuticals, Pierre Fabre, Roche/Genentech, and Zodiac Pharma, all paid to immediate family member and outside of the submitted work; and co-director position at West German Study Group. MG received consulting fees from AstraZeneca and travel support from Daiichi Sankyo, all outside of the submitted work. RW received consulting fees, honoraria, and travel support from Agendia, Amgen, Aristo, AstraZeneca, Boeringer Ingelheim, Carl Zeiss, Celgene, Daiichi-Sankyo, Eisai, Exact Sciences/Genomic Health, Gilead, Glaxo Smith Kline, Hexal, Lilly, Medstrom Medical, MSD, Mundipharma, Mylan, Nanostring, Novartis, Odonate, Paxman, Palleos, Pfizer, Pierre Fabre, PumaBiotechnology, Riemser, Roche, Sandoz/Hexal, Sanofi Genzyme, Seattle Genetics/Seagen, Tesaro Bio, Teva, Veracyte, and Viatris; and other financial or non-financial interests from FomF (Forum for medical education in Germany), Aurikamed, Clinsol, Pomme Med, all outside of the submitted work. RB is a current employee of and owns stock in Exact Sciences Corporation. HHK received honoraria for lectures from Roche Pharma, Novartis, Genomic Health, AstraZeneca, Lilly, and Pfizer; and participation in Data Safety Monitoring Board or Advisory Board at Roche Pharma, Genomic Health, and AstraZeneca, all outside of the submitted work. NH received research funding paid to institution from Lilly, MSD, Novartis, Pfizer, and Roche/Genentech; honoraria for lectures and/or consulting from Amgen, AstraZeneca, Daiichi Sankyo, Gilead, Lilly, MSD, Novartis, Pierre Fabre, Pfizer Pharmaceuticals, Roche/Genentech, Sandoz, Sanofi, and Seagen, all outside of the submitted work. All other authors have declared no conflicts of interest., (Copyright © 2023 European Society for Medical Oncology. Published by Elsevier Ltd. All rights reserved.)

Purpose: Although representing the majority of newly diagnosed cancers, patients with breast cancer appear less vulnerable to COVID-19 mortality compared with other malignancies. In the absence of patients on active cancer therapy included in vaccination trials, a contemporary real-world evaluation of outcomes during the various pandemic phases, as well as of the impact of vaccination, is needed to better inform clinical practice., Methods: We compared COVID-19 morbidity and mortality among patients with breast cancer across prevaccination (February 27, 2020-November 30, 2020), Alpha-Delta (December 1, 2020-December 14, 2021), and Omicron (December 15, 2021-January 31, 2022) phases using OnCovid registry participants (ClinicalTrials.gov identifier: NCT04393974). Twenty-eight-day case fatality rate (CFR 28 ) and COVID-19 severity were compared in unvaccinated versus double-dosed/boosted patients (vaccinated) with inverse probability of treatment weighting models adjusted for country of origin, age, number of comorbidities, tumor stage, and receipt of systemic anticancer therapy within 1 month of COVID-19 diagnosis., Results: By the data lock of February 4, 2022, the registry counted 613 eligible patients with breast cancer: 60.1% (n = 312) hormone receptor-positive, 25.2% (n = 131) human epidermal growth factor receptor 2-positive, and 14.6% (n = 76) triple-negative. The majority (61%; n = 374) had localized/locally advanced disease. Median age was 62 years (interquartile range, 51-74 years). A total of 193 patients (31.5%) presented ≥ 2 comorbidities and 69% (n = 330) were never smokers. In total, 392 (63.9%), 164 (26.8%), and 57 (9.3%) were diagnosed during the prevaccination, Alpha-Delta, and Omicron phases, respectively. Analysis of CFR 28 demonstrates comparable estimates of mortality across the three pandemic phases (13.9%, 12.2%, 5.3%, respectively; P = .182). Nevertheless, a significant improvement in outcome measures of COVID-19 severity across the three pandemic time periods was observed. Importantly, when reported separately, unvaccinated patients from the Alpha-Delta and Omicron phases achieved comparable outcomes to those from the prevaccination phase. Of 566 patients eligible for the vaccination analysis, 72 (12.7%) were fully vaccinated and 494 (87.3%) were unvaccinated. We confirmed with inverse probability of treatment weighting multivariable analysis and following a clustered robust correction for participating center that vaccinated patients achieved improved CFR 28 (odds ratio [OR], 0.19; 95% CI, 0.09 to 0.40), hospitalization (OR, 0.28; 95% CI, 0.11 to 0.69), COVID-19 complications (OR, 0.16; 95% CI, 0.06 to 0.45), and reduced requirement of COVID-19-specific therapy (OR, 0.24; 95% CI, 0.09 to 0.63) and oxygen therapy (OR, 0.24; 95% CI, 0.09 to 0.67) compared with unvaccinated controls., Conclusion: Our findings highlight a consistent reduction of COVID-19 severity in patients with breast cancer during the Omicron outbreak in Europe. We also demonstrate that even in this population, a complete severe acute respiratory syndrome coronavirus 2 vaccination course is a strong determinant of improved morbidity and mortality from COVID-19.

Background: Efficacy and quality of life (QoL) are key criteria for therapy selection in metastatic breast cancer (MBC). In hormone receptor positive (HR +) human epidermal growth factor receptor 2 negative (HER2 -) MBC, addition of targeted oral agents such as everolimus or a cycline-dependent kinase 4/6 (CDK 4/6) inhibitor (e.g., palbociclib, ribociclib, abemaciclib) to endocrine therapy substantially prolongs progression-free survival and in the case of a CDK 4/6i also overall survival. However, the prerequisite is adherence to therapy over the entire course of treatment. However, particularly with new oral drugs, adherence presents a challenge to disease management. In this context, factors influencing adherence include maintaining patients' satisfaction and early detection/management of side effects. New strategies for continuous support of oncological patients are needed. An eHealth-based platform can help to support therapy management and physician-patient interaction., Methods: PreCycle is a multicenter, randomized, phase IV trial in HR + HER2 - MBC. All patients (n = 960) receive the CDK 4/6 inhibitor palbociclib either in first (62.5%) or later line (37.5%) together with endocrine therapy (AI, fulvestrant) according to national guidelines. PreCycle evaluates and compares the time to deterioration (TTD) of QoL in patients supported by eHealth systems with substantially different functionality: CANKADO active vs. inform. CANKADO active is the fully functional CANKADO-based eHealth treatment support system. CANKADO inform is a CANKADO-based eHealth service with a personal login, documentation of daily drug intake, but no further functions. To evaluate QoL, the FACT-B questionnaire is completed at every visit. As little is known about relationships between behavior (e.g., adherence), genetic background, and drug efficacy, the trial includes both patient-reported outcome and biomarker screening for discovery of forecast models for adherence, symptoms, QoL, progression free survival (PFS), and overall survival (OS)., Discussion: The primary objective of PreCycle is to test the hypothesis of superiority for time to deterioration (TTD) in terms of DQoL = "Deterioration of quality of life" (FACT-G scale) in patients supported by an eHealth therapy management system (CANKADO active) versus in patients merely receiving eHealth-based information (CANKADO inform). EudraCT Number: 2016-004191-22., (© 2023. The Author(s).)

Background: Mutations in the p110α catalytic subunit of phosphatidylinositol 3-kinase (PI3K), encoded by the PIK3CA gene, cause dysregulation of the PI3K pathway in 35-40% of patients with HR+/HER2- breast cancer. Preclinically, cancer cells harboring double or multiple PIK3CA mutations (mut) elicit hyperactivation of the PI3K pathway leading to enhanced sensitivity to p110α inhibitors., Methods: To understand the role of multiple PIK3CAmut in predicting response to p110α inhibition, we estimated the clonality of multiple PIK3CAmut in circulating tumor DNA (ctDNA) from patients with HR+/HER2- metastatic breast cancer enrolled to a prospectively registered clinical trial of fulvestrant ± taselisib, and analyzed the subgroups against co-altered genes, pathways, and outcomes., Results: ctDNA samples with clonal multiple PIK3CAmut had fewer co-alterations in receptor tyrosine kinase (RTK) or non-PIK3CA PI3K pathway genes compared to samples with subclonal multiple PIK3CAmut indicating a strong reliance on the PI3K pathway. This was validated in an independent cohort of breast cancer tumor specimens that underwent comprehensive genomic profiling. Furthermore, patients whose ctDNA harbored clonal multiple PIK3CAmut exhibited a significantly higher response rate and longer progression-free survival vs subclonal multiple PIK3CAmut., Conclusions: Our study establishes clonal multiple PIK3CAmut as an important molecular determinant of response to p110α inhibition and provides rationale for further clinical investigation of p110α inhibitors alone or with rationally-selected therapies in breast cancer and potentially other solid tumor types., (© 2023. The Author(s).)

TP53 mutation is associated with primary endocrine resistance in luminal breast cancer (BC). Nuclear accumulation of p53, as determined by immunohistochemistry (IHC), is a surrogate marker for TP53 mutation. The immunohistochemical p53 index that defines a p53-positive status is not well established. This study determined the optimal p53 index cutoff to identify luminal BCs harboring TP53 mutations. In total, 364 luminal BCs from the West German Study Group ADAPT trial (NCT01779206) were analyzed for TP53 mutations by next-generation sequencing and for p53 expression by IHC (DO-7 antibody). P53 indices were determined by automated image analysis. All tumors were from patients treated with short-term preoperative endocrine therapy (pET; tamoxifen or aromatase inhibitor) before tumor resection. IHC evaluation included needle biopsies before therapy (baseline) and resections specimens after therapy (post-pET). Optimal p53 index cutoffs were defined with Youden statistics. TP53 mutations were detected in 16.3% of BC cases. The median p53 indices were significantly higher in TP53-mutated BCs compared to BCs harboring wild-type TP53 (baseline: 47.0% vs 6.4%, P < .001; post-pET: 50.1% vs 1.1%, P < .001). Short-term pET decreased p53 indices in BCs harboring wild-type TP53 (P < .001) but not in TP53-mutated BCs (P = .102). For baseline biopsies, the optimal p53 index cutoff was ≥34.6% (specificity 0.92, sensitivity 0.63, Youden index 0.54, accuracy: 0.87). For post-pET specimens, the optimal cutoff was ≥25.3% (specificity 0.95, sensitivity 0.65, Youden index 0.60, accuracy: 0.90). Using these cutoffs to define the p53 status, p53-positive BCs were >2-fold more common in pET nonresponders compared to pET responders (baseline: 37/162, 22.8% vs 18/162, 11.1%, P = .007; post-pET: 36/179, 20.1% vs 16/179, 8.9%, P = .004). In summary, IHC for p53 identifies TP53-mutated luminal BCs with high specificity and accuracy. Optimal cutoffs are ≥35% and ≥25% for treatment-naïve and endocrine-pretreated patients, respectively., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Purpose: Evidence about routine treatment and outcome of patients with invasive lobular cancer (ILC) is limited, especially regarding metastatic disease. Here we present prospective real-world data of patients with metastatic ILC (mILC) as compared to patients with metastatic invasive ductal cancer (mIDC) receiving systemic therapy in routine care in Germany., Methods: Prospective data on patient and tumor characteristics, treatments, and outcomes of patients with mILC (n = 466) and mIDC (n = 2100), recruited between 2007 and 2021 into the Tumor Registry Breast Cancer/OPAL were analyzed., Results: Compared to mIDCs, patients with mILC were older at start of first-line treatment (median 69 vs. 63 years) and had more often lower grade (G1/G2: 72.8% vs. 51.2%), hormone receptor (HR)-positive (83.7% vs. 73.2%) and less often HER2-positive (14.2% vs. 28.6%) tumors, which metastasized more frequently to the bone (19.7% vs. 14.5%) or peritoneum (9.9% vs. 2.0%), and less frequently to the lungs (0.9% vs. 4.0%). Median OS of patients with mILC (n = 209) and mIDC (n = 1158) was 30.2 months [95% confidence interval (CI) 25.3, 36.0] and 33.7 months [95% CI 30.3, 37.9], respectively. Multivariate survival analysis did not show a significant prognostic impact of the histological subtype [HR mILC vs. mIDC 1.18 (95% CI 0.97-1.42)]., Conclusion: Overall, our real-world data confirm clinicopathological differences between mILC and mIDC breast cancer patients. Despite patients with mILC presenting with some favorable prognostic factors, ILC histopathology was not associated with a better clinical outcome in multivariate analysis, suggesting the need for more tailored treatment strategies for patients with the lobular subtype., (© 2023. The Author(s).)

Purpose: To identify associations of biological signatures and stromal tumor-infiltrating lymphocytes (sTIL) with pathological complete response (pCR; ypT0 ypN0) and survival in the Phase II WSG-ADAPT HER2+/HR- trial (NCT01817452)., Experimental Design: Patients with cT1-cT4c, cN0-3 HER2+/HR- early breast cancer (EBC) were randomized to pertuzumab+trastuzumab (P+T, n = 92) or P+T+paclitaxel (n = 42). Gene expression signatures were analyzed in baseline biopsies using NanoString Breast Cancer 360 panel (n = 117); baseline and on-treatment (week 3) sTIL levels were available in 119 and 76 patients, respectively. Impacts of standardized gene expression signatures on pCR and invasive disease-free survival (iDFS) were estimated by logistic and Cox regression., Results: In all patients, ERBB2 [OR, 1.70; 95% confidence interval (CI), 1.08-2.67] and estrogen receptor (ER) signaling (OR, 1.72; 95% CI, 1.13-2.61) were favorable, whereas PTEN (OR, 0.57; 95% CI, 0.38-0.87) was unfavorable for pCR. After 60 months median follow-up, 13 invasive events occurred (P+T: n = 11, P+T+paclitaxel: n = 2), none following pCR. Gene signatures related to immune response (IR) and ER signaling were favorable for iDFS, all with similar HR about 0.43-0.55. These patterns were even more prominent in the neoadjuvant chemotherapy-free group, where additionally BRCAness signature was unfavorable (HR, 2.00; 95% CI, 1.04-3.84). IR signatures were strongly intercorrelated. sTILs (baseline/week 3/change) were not associated with pCR or iDFS, though baseline sTILs correlated positively with IR signatures., Conclusions: Distinct gene signatures were associated with pCR versus iDFS in HER2+/HR- EBC. The potential role of IR in preventing recurrence suggests that patients with upregulated IR signatures could be candidates for de-escalation concepts in HER2+ EBC., (©2022 The Authors; Published by the American Association for Cancer Research.)

Competing Interests: Disclosure CS has reported non-remunerated activities as Coordinator Gynecological Programme for the European School of Oncology. JB has reported fees for advisory board membership for AstraZeneca and Pfizer; fees paid to her institute for roles as local principal investigator for AstraZeneca, MedSire and Pfizer. SLB has reported fees as an author for UpToDate. She has also reported non-remunerated activities as the chair of the Scientific Network on Female Sexual Health and Cancer (academic organisation). MJC has reported fees as an invited speaker for Roche (industry-sponsored symposium in National Conference). She has also reported non-remunerated activities as a member of the Board of Directors of EUSOMA, faculty member of ESO, project lead/lead investigator for the Breast Research Group of INESC TEC and President of MAMA Help (non-profit association for breast cancer patients in Portugal). She serves as a Specialty Editor for The Breast. NC has reported fees for advisory board membership for AstraZeneca, BIOCAD, Clovis Oncology, Eisai, GlaxoSmithKline (GSK), ImmunoGen, Mersana, Merck Sharp & Dohme (MSD)/Merck, Nuvation Bio, OncXerna, Pfizer, PharmaMar, Pieris and Roche; fees as an invited speaker for AstraZeneca, Clovis Oncology, GSK and MSD/Merck; institutional research grants from AstraZeneca, PharmaMar and Roche. She has also reported non-remunerated activities as member of the ESMO Guidelines Steering Committee and chair of the Scientific Committee of Alleanza contro il Tumore Ovarico (ACTO). GC has reported fees for advisory board membership for AstraZeneca, Bristol Myers Squibb (BMS), Celcuity, Daiichi Sankyo, Ellipsis, Exact Sciences, Lilly, Merck, Pfizer, Roche and Veracyte; fees as an invited speaker for AstraZeneca, Daiichi Sankyo, Novartis, Pfizer and Roche; fees for a writing engagement from Pfizer; institutional research grant from Merck for an investigator-initiated trial; institutional funding for phase I studies from Astellas, AstraZeneca, Blueprint Medicine, BMS, Daiichi Sankyo, Kymab, Novartis, Philogen, Relay Therapeutics, (coordinating principal investigator), Roche and Sanofi. He has also reported non-remunerated activities as an Italian National Health Council as Advisor for Ministry of Health (Consiglio Superiore di Sanità), member of the Scientific Council for the patient advocacy association Europa Donna, advisory role at the Fondazione Beretta cancer research foundation, member of the Board of Directors for Lega Italian Lotta ai Tumori (public national company for cancer prevention) and member of the Advisory Council of EUSOMA. SMD has reported personal honoraria from AstraZeneca, BMS and Clovis; fees paid to her institute as coordinating principal investigator for AstraZeneca. DGE has reported fees for advisory board membership for Recursion, SpringWorks and Syantra; consultancy fees for a writing engagement for AstraZeneca. DF has declared no conflicts of interest. NH has reported fees for advisory board membership for Aptitude Health, AstraZeneca, Daiichi Sankyo, Gilead, Novartis, Pfizer, Roche, Sandoz-Hexal, Sanofi and SeaGen; fees as an invited speaker for Art Tempi, AstraZeneca, Daiichi Sankyo, Exact Sciences, Gilead, Lilly, Medscape, MSD, Novartis, Onkowissen, Pierre Fabre, Roche, Sanofi and SeaGen; institutional funding from AstraZeneca, BMS, Daiichi Sankyo, Lilly, MSD, Novartis, Palleos, Pierre Fabre, Roche, SeaGen, TRIO and WSG; ownership interest in the West German Study Group. She has also reported non-remunerated activities as a member of the AGO Breast Guideline Committee and member of the ESO/ESCO Breast Cancer Educational Programs. She is the Founding Editor of the Breast Care journal. CK has reported fees for advisory board membership for Guerbet; fees as an invited speaker for Bayer and Bracco. BL has reported fees received from the Rising Tide Foundation as a patient reviewer. She has also reported non-remunerated activities as a member of the European Society of Gynaecological Oncology (ESGO) ENGAGe (Past Executive Board Member) and chair of KIU—Danish Patient Organisation for Women with Gynaecological Cancer. ELL has reported employment as the Director of the Medical Genetics Institute of the Shaare Zedek Medical Center. She has also reported non-remunerated activity as the vice president of the Israel National Academy of Science in Medicine (non-profit). ML has reported fees for advisory board membership and speaker fees for AstraZeneca, Exact Sciences, Gilead, Lilly, MSD, Novartis, Roche and SeaGen; fees as an invited speaker for Ipsen, Knight, Libbs, Pfizer, Sandoz, SeaGen and Takeda. JAL has reported fees for advisory board membership for Artios Pharma, AstraZeneca, BMS, Clovis Oncology, Eisai, Ellipses, GSK, ImmunoGen, Merck/MSD, Nuvation, Pfizer and VBL Therapeutics; speaker fees from AstraZeneca, Clovis Oncology, GSK and Neopharm; fees related to an independent data monitoring committee for Regeneron; institutional research grants from AstraZeneca, Clovis Oncology, Eisai, GSK, MSD/Merck and Pfizer. He has also reported non-remunerated activities as vice president of the European Society of Gynaecological Oncology (2019-2021). He serves as an associate editor of Therapeutic Advances in Medical Oncology (Sage Publishing). SL has reported fees paid to her institute for advisory board membership for AbbVie, Amgen, AstraZeneca, BMS, Celgene, DSI, EirGenix, Gilead, GSK, Lilly, Merck, Novartis, Pfizer, Pierre Fabre, Relay Therapeutics, Roche, Sanofi and SeaGen; fees paid to her institute as an invited speaker for AstraZeneca, DSI, Gilead, Novartis, Pfizer and Roche; employment as the Chief Executive officer (CEO) of GBG Forschungs GmbH; licensing fees paid to her institute by VM Scope GmbH; research grants to her institute from AstraZeneca, Celgene, Daiichi Sankyo, Immunomedics/Gilead, Novartis, Pfizer and Roche; institutional funding from AbbVie and Molecular Health; fees paid to her institute as principal investigator (Penelope/Padma) from Pfizer; fees paid to her institute from AstraZeneca (SC Capitello), Daiichi Sankyo (SC Destiny B05), Immunomedics/Gilead (SC ASCENT), Novartis (SC SOLAR1), Pfizer (SC PALOMA3), Roche (SC Inavo and SC Katherine), SeaGen (SC HERCLIMB). She has also reported non-remunerated activities as principal investigator for Aphinity, advisory role to Arbeitsgemeinschaft Gynäkologische Onkologie (AGO) Kommission Mamma (group in Germany responsible for breast cancer guidelines), membership of AGO, Deutsche Krebsgesellschaft (DKG), American Society of Clinical Oncology (ASCO) and ESMO including membership of the ESMO Guidelines Committee and past chair of the ESMO Breast Congress. She has reported institutional patents for which she has no financial interests: EP14153692.0, EP21152186.9, EP15702464.7, EP19808852.8. K-AP has reported non-remunerated activities as advisory board member for AstraZeneca, Scientific Advisory Committee member for Breast Cancer Trials, project lead in Australia for the DECRESENDO and OlympiA studies, member of the Expert Advisory Group on Cancer Clusters for the Victorian Department of Health and Human Services, Strategic Advisory Committee member for Breast Cancer Network Australia, Cancer Genetics Reference Committee Member for New South Wales Cancer Institute; advisory role on the register of experts for breast and hereditary cancer for the Medical Oncology Group of Australia and breast cancer optimal care pathway committee member for Cancer Council Victoria. She is also a leadership fellow of the National Health and Medical Research Council (Australia) and a practitioner fellow of the National Breast Cancer Foundation (Australia). SP-S has reported fees paid to her institute for advisory board membership for AstraZeneca, Eli Lilly, Exact Sciences, Medison, Pfizer and Roche; fees paid to her institute as an invited speaker for AstraZeneca, Eli Lilly, Exact Sciences, Medison, Novartis, Pfizer and Roche; fees paid to her institute for consultancy for Medison; personal and institutional research grant for an request for proposal for independent research put out by Shared Progress in Cancer Care and Pfizer.

Background: Adjuvant abemaciclib plus endocrine therapy previously showed a significant improvement in invasive disease-free survival and distant relapse-free survival in hormone receptor-positive, human epidermal growth factor receptor 2 (HER2; also known as ERBB2)-negative, node-positive, high-risk, early breast cancer. Here, we report updated results from an interim analysis to assess overall survival as well as invasive disease-free survival and distant relapse-free survival with additional follow-up., Methods: In monarchE, an open-label, randomised, phase 3 trial, adult patients (aged ≥18 years) who had hormone receptor-positive, HER2-negative, node-positive, early breast cancer at a high risk of recurrence with an Eastern Cooperative Oncology Group performance status of 0 or 1 were recruited from 603 sites including hospitals and academic and community centres in 38 countries. Patients were randomly assigned (1:1) by means of an interactive web-based response system (block size of 4), stratified by previous chemotherapy, menopausal status, and region, to receive standard-of-care endocrine therapy of physician's choice for up to 10 years with or without abemaciclib 150 mg orally twice a day for 2 years (treatment period). All therapies were administered in an open-label manner without masking. High-risk disease was defined as either four or more positive axillary lymph nodes, or between one and three positive axillary lymph nodes and either grade 3 disease or tumour size of 5 cm or larger (cohort 1). A smaller group of patients were enrolled with between one and three positive axillary lymph nodes and Ki-67 of at least 20% as an additional risk feature (cohort 2). This was a prespecified overall survival interim analysis planned to occur 2 years after the primary outcome analysis for invasive disease-free survival. Efficacy was assessed in the intention-to-treat population. Safety was assessed in all treated patients. The study is registered with ClinicalTrials.gov, NCT03155997, and is ongoing., Findings: Between July 17, 2017, and Aug 12, 2019, 5637 patients were randomly assigned (5601 [99·4%] were women and 36 [0·6%] were men). 2808 were assigned to receive abemaciclib plus endocrine therapy and 2829 were assigned to receive endocrine therapy alone. At a median follow-up of 42 months (IQR 37-47), median invasive disease-free survival was not reached in either group and the invasive disease-free survival benefit previously reported was sustained: HR 0·664 (95% CI 0·578-0·762, nominal p<0·0001). At 4 years, the absolute difference in invasive disease-free survival between the groups was 6·4% (85·8% [95% CI 84·2-87·3] in the abemaciclib plus endocrine therapy group vs 79·4% [77·5-81·1] in the endocrine therapy alone group). 157 (5·6%) of 2808 patients in the abemaciclib plus endocrine therapy group died compared with 173 (6·1%) of 2829 patients in the endocrine therapy alone group (HR 0·929, 95% CI 0·748-1·153; p=0·50). The most common grade 3-4 adverse events were neutropenia (in 548 [19·6%] of 2791 patients receiving abemaciclib plus endocrine therapy vs 24 [0·9%] of 2800 patients in the endocrine therapy alone group), leukopenia (318 [11·4%] vs 11 [0·4%]), and diarrhoea (218 [7·8%] vs six [0·2%]). Serious adverse events occurred in 433 (15·5%) of 2791 patients receiving abemaciclib plus endocrine therapy versus 256 (9·1%) of 2800 receiving endocrine therapy. There were two treatment-related deaths in the abemaciclib plus endocrine therapy group (diarrhoea and pneumonitis) and none in the endocrine therapy alone group., Interpretation: Adjuvant abemaciclib reduces the risk of recurrence. The benefit is sustained beyond the completion of treatment with an absolute increase at 4 years, further supporting the use of abemaciclib in patients with high-risk hormone receptor-positive, HER2-negative early breast cancer. Further follow-up is needed to establish whether overall survival can be improved with abemaciclib plus endocrine therapy in these patients., Funding: Eli Lilly., Competing Interests: Declaration of interests SRDJ reports grants or contracts from Pfizer, Puma Biotechnology, Eli Lilly, AstraZeneca, Novartis, and Roche–Genentech for research funding to institute for laboratory studies and clinical trials; consulting fees from Eli Lilly, AstraZeneca, Puma Biotechnology, Pfizer, Novartis, and Sanofi Genzyme for consulting or an advisory role; and payment or honoraria from Pfizer, Eisai, AstraZeneca, and Roche–Genentech for speaker's bureau. MT reports grants or contracts from Chugai, Takeda, Pfizer, Taiho, JBCRG, KBCRN, Eisai, Eli Lilly, Daiichi-Sankyo, AstraZeneca, Astellas, Shimadzu, Yakult, Nippon Kayaku, AFI technology, Luxonus, Shionogi, GL Science, and Sanwa Shurui for research grants to their department; payment or honoraria from Chugai, Takeda, Pfizer, Kyowa-Kirin, Taiho, Eisai, Daiichi-Sankyo, AstraZeneca, Eli Lilly, Merck Sharp and Dohme, Exact Science, Novartis, Shimadzu, Yakult, Nippon Kayaku, Devicore Medical Japan, and Sysmex for lecture honoraria or honoraria for lecture chair; participation on a data safety monitoring board or advisory board for Daiichi-Sankyo, Eli Lilly, Bristol Myers Squibb, Athenex Oncology, Bertis, Terumo, and Kansai Medical Net; and other financial or non-financial interest from British Journal of Cancer, Scientific Reports, Breast Cancer Research and Treatment, Cancer Science, Frontiers in Women's Cancer, Asian Journal of Surgery, and Asian Journal of Breast Surgery for his role as Associate Editor. JO'S reports consulting fees and payment or honoraria for lectures, presentations, speaker's bureaus, manuscript writing or educational events from from AbbVie, Agendia, Amgen Biotechnology, Aptitude Health, AstraZeneca, Athenex, Bayer, Bristol Myers Squibb, Carrick Therapeutics, Celgene Corporation, Daiichi Sankyo, Eisai, G1 Therapeutics, Genentech, Genzyme, Gilead Sciences, GRAIL, Halozyme Therapeutics, Heron Therapeutics, Immunomedics, Ipsen Biopharmaceuticals, Eli Lilly, Merck, Myriad, Nektar Therapeutics, Novartis, Ontada, Pfizer, Pharmacyclics, Pierre Fabre Pharmaceuticals, Puma Biotechnology, Prime Oncology, Roche, Samsung Bioepsis, Sandoz, Sanofi, Seagen, Syndax Pharmaceuticals, Taiho Oncology, Takeda, Theralink, and Synthon. MC reports personal payment support from Eli Lilly for the present article, advisory board, and speaker's bureau; payment or honoraria to institution from Novartis; support for attending meetings from Eli Lilly, Novartis, AstraZeneca, and Pfizer; and payment to institution from AstraZeneca, Novartis, Sanofi, Pfizer, Seagen, Gilead, Daiichi Sankyo for participation on a data safety monitoring board or advisory board. C-SH reports research grants to institution from Eli Lilly for the present article; research grants to institution or contracts from Daiichi Sankyo, AstraZeneca, EirGenix, Eli Lilly and Company, Merck Sharp and Dohme, OBI Pharma, Pfizer, Roche, and Novartis; payment or honoraria from Daiichi Sankyo, AstraZeneca, Pfizer, Novartis, Roche, and Eli Lilly for speaker's bureau; support for attending meetings or travel from Astra Zeneca, Pfizer, Roche, and Novartis; and participation on advisory boards from Daiichi Sankyo, AstraZeneca, Eli Lilly, Pfizer, Novartis, and Roche. JH reports institutional grants or contracts from Celgene, Novartis, Hexal, and Eli Lilly; consulting fees paid to self from Eli Lilly, Novartis, Roche, Pfizer, Hexal, AstraZeneca, Merck Sharp and Dohme, Celgene, AbbVie, and Daiichi-Sankyo; honoraria or payments to self for lectures, presentation, speaker's bureaus, manuscript writing, or educational events from Eli Lilly, Novartis, Roche, Pfizer, AstraZeneca, Merck Sharp and Dohme, Celgene, Eisai, Abbvie, Seagen, and Gilead; and support for attending meetings or travel paid to self from Roche, Pfizer, Novartis, Celgene, Daiichi-Sankyo, and Gilead. SMT reports institutional funding for study, consulting work to personal (honorariums), and manuscript preparation from Eli Lilly; institutional grants or contracts from AstraZeneca, Merck, Mektar, Novartis, Pfizer, Genentech–Roche, Gilead, Exelixis, Bristol Myers Squibb, Eisai, Nanostring, Cyclacel, Sanofi, and Seagen; and honoraria payments to self for participation in advisory boards or consulting from AstraZeneca, Eli Lilly, Merck, Novartis, Pfizer, Genentech–Roche, Gilead, Bristol Myers Squibb, Eisai, Sanofi, Seagen, Daiichi-Sankyo, Athenex, OncoPep, Kyowa Kirin Pharma, CytomX, Certara, Mersana Therapeutics, Ellipses Pharma, 4D Pharma, OncoSec, Infinity Therapeutics, BeyondSpring Pharma, OncXerna, Zymeworks, Zentalis, ARC Therapeutics, Reveal Genomics, Blueprint Medicines, Myovant, Umoja Biopharma, and Menarini–Stemline. MPG reports institutional grants or contracts from Pfizer, Eli Lilly, and Sermonix; consulting fees to institution from Eagle Pharmaceuticals, Eli Lilly, Biovica, Novartis, Sermonix, Pfizer, and ARC Therapeutics; honoraria or payment to self for lectures, presentations, speaker's bureaus, manuscript writing, or educational events from Research to Practice, Clinical Education Alliance, Medscape, Total Health Conferencing, Curio Science, and MJH Life Sciences; and support to institution from Eli Lilly, AstraZeneca, Novartis, Biotheranostics, Blueprint Medicines, Sanofi Genzyme, and ARC Therapeutics for participation on a data safety monitoring board or advisory board. HSR reports institutional research support from Pfizer, Novartis, Eli Lilly, Genentech–Roche, OBI, Merck, Gilead Sciences, Daiichi Sankyo, Seattle Genetics, Sermonix, AstraZeneca, and Astellas; travel support to academic meetings from Merck, AstraZeneca, and Gilead; and consulting or advisory support from Puma, NAPO, and Blueprint. ES reports support from Eli Lilly for the present article including investigator fees and medical writing; payment or honoraria for lectures, presentations, speaker's bureaus, manuscript writing, or educational events from AstraZeneca, Cancérodigest, Curio, Science, Egis, Eli Lilly and Company, Exact Sciences, Gilead, high5md, Merck Sharp and Dohme, Novartis, Pfizer, and Pierre Fabre; support for attending meetings or travel from Egis, Gilead, Novartis, Pfizer, and Roche; participation on a data safety monitoring board or advisory board from AstraZeneca, Egis, Eli Lilly, Exact Sciences, Merck Sharp and Dohme, Novartis, and Pfizer; a leadership or fiduciary role from Stowarzyszenie Różowy Motyl as Chair (unpaid); stock or stock options from AstraZeneca, Eli Lilly, and Pfizer; receipt of equipment, materials, drugs, medical writing, gifts or other services from Astellas, AstraZeneca, and Eli Lilly; and other financial or non-financial interests from Amgen, AstraZeneca, Eli Lilly, Novartis, OBI Pharma, Pfizer, Roche, and Samsung for contracted research. LT reports support from Eli Lilly as the trial sponsor for the study; grants or contracts from Novartis for clinical research; consulting fees from Merck Sharp and Dohme, Eli Lilly, and Novartis for advisory board; payment or honoraria from Merck Sharp and Dohme, Eli Lilly, Pfizer, Daiichi Sankyo, Novartis, and AstraZeneca for medical education; and support for attending meetings or travel from Pfizer and AstraZeneca. LDM reports an institutional research grant from Eli Lilly, Novartis, Roche, Daiichi Sankyo, and Seagen; consulting fees paid to self from Eli Lilly; honoraria or payment to self from Roche, Novartis, Pfizer, Eli Lilly, AstraZeneca, Merck Sharp and Dohme, Seagen, Gilead, Pierre Fabre, Eisa, Exact Sciences, and Ipsen for lectures, presentations, speaker's bureaus, manuscript writing or educational events; support for attending meetings or travel from Roche, Pfizer, and Eisai; and fees paid to self for participation on a data safety monitoring board or advisory Board from Novartis, Roche, Eli Lilly, Pfizer, Daiichi-Sankyo, Exact Sciences, Gilead, Pierre Fabre, Eisai, AstraZeneca, and Agendia. CS reports research grants from Eli Lilly, and honoraria for lectures from Pfizer and Eli Lilly. RW, AS, MMu, BSA, VA are employees and stock shareholders of Eli Lilly. NH reports support for the present article (medical writing) from Eli Lilly; consulting fees from Gilead, Sandoz, and Seagen; payment or honoraria for lectures, presentations, speaker's bureaus, manuscript writing, or educational events from Amgen, AsraZeneca, Daiichi-Sankyo, Gilead, Eli Lilly, Merck Sharp and Dohme, Novartis, Pierre-Fabre, Pfizer, Roche, and Seagen; participation on a data safety monitoring board or advisory board from Roche; and a leadership or fiduciary role with the West German Study Group and ESMO. MMa reports institutional grants from Roche, Novartis, and Puma; consulting fees paid to self from Roche, Eli Lilly, Pfizer, Daiichi-Sankyo, AstraZeneca, and Novartis; payment or honoraria to self for lectures, presentations, speaker's bureaus, manuscript writing, or educational events from Roche, Eli Lilly, Astrazeneca, and Pfizer; support paid to self for attending meetings or travel from Daiichi-Sankyo and Roche; and support paid to self for participation on a data safety monitoring board or advisory board from Novartis. PR, PN, GGJ, and IC declare no competing interests., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Human epidermal growth factor receptor 2 oncogene (HER2-positive) overexpression/amplification occurs in less than 20% of breast cancers and has traditionally been associated with poor prognosis. Development of therapies that target HER2 has significantly improved outcomes for patients with HER2-positive advanced breast cancer (ABC). Currently available HER2-targeted agents include the monoclonal antibodies trastuzumab, pertuzumab, and margetuximab, the small-molecule inhibitors lapatinib, tucatinib, neratinib, and pyrotinib, as well as the antibody-drug conjugates trastuzumab emtansine and trastuzumab deruxtecan. Optimal sequencing of these agents in the continuum of the disease is critical to maximize treatment outcomes. The large body of clinical evidence generated over the past 2 decades aids clinicians in treatment decision-making. However, patients with HER2-positive ABC and specific disease characteristics and/or comorbidities, such as leptomeningeal disease, brain metastases, or cardiac dysfunction, are generally excluded from large randomized clinical trials, and elderly or frail patients are often underrepresented. In addition, there is great inequality in the accessibility of approved drugs across countries. This article addresses various challenging clinical situations when treating patients with HER2-positive ABC. The objective is to provide guidance to clinicians on how and when HER2-targeted therapies and additional treatments can be best implemented in routine clinical practice, on the basis of existing clinical evidence and expert opinion where needed., Competing Interests: Declaration of interest statements Matti Aapro: Advisor for Eisai, Helsinn, Merck, Mundipharma, Roche, and Tesaro; honoraria from Eisai, Helsinn, Merck, Mundipharma, Roche, and Tesaro; grants from Helsinn, Merck, Roche, and Tesaro. Fatima Cardoso: Consultancy fees for: Amgen, Astellas/Medivation, AstraZeneca, Celgene, Daiichi Sankyo, Eisai, GE Oncology, Genentech, Gilead, GlaxoSmithKline, IQVIA, MacroGenics, Medscape, Merck Sharp, Merus BV, Mylan, Mundipharma, Novartis, Pfizer, Pierre Fabre, prIME Oncology, Roche, Sanofi, Samsung Bioepis, Seagen, Teva, touchIME. Giuseppe Curigliano: Personal fees from Roche, Pfizer, Novartis, Lilly, Foundation Medicine, Samsung, AstraZeneca, Daichii Sankyo, GSK, Seagen; non-financial support from Roche, Pfizer; grants from Merck; other from Ellipses, outside the submitted work. Alexandru Eniu: Grants/Research support from AstraZeneca, Roche Celltrion, Pfizer, and Novartis; honoraria or consultation fees from Merck Sharp & Dohme, Gilead, Seagen, Novartis, and Janssen. Joseph Gligorov: Grants, personal fees and non-financial support for clinical trials, travel support, advisory boards, and speakers' bureaus from Roche-Genentech, Eisai, Exact Sciences, and Pfizer; personal fees and nonfinancial support for clinical trials, travel support, advisory boards, and speakers' bureaus from Novartis and Lilly; personal fees and nonfinancial support for clinical trials and advisory boards from Daiichi Sankyo and MSD; grants and personal fees for travel support, advisory boards, and speakers' bureaus from Mylan; personal fees and nonfinancial support for travel support, advisory boards, and speakers' bureaus from Pierre Fabre; and personal fees for advisory boards and speakers’ bureaus from AstraZeneca, outside the submitted work. Nadia Harbeck: Honoraria for lectures and/or consulting: Amgen, AstraZeneca, Daiichi Sankyo, Exact Sciences, Gilead, Lilly, MSD, Novartis, Pierre Fabre, Pfizer, Roche, Sandoz, and Seagen. Andreas Mueller: Stock and other ownership interests from Vifor Pharma; honoraria from Eli Lilly and Novartis; consulting or advisory role for Novartis, Eli Lilly, Pfizer, Genomic Health, AstraZeneca, Roche, Daiichi Sankyo, Merck Sharp & DohmeMerck Sharp & Dohme, Pierre Fabre, Exact Sciences, Myriad Genetics, Gilead Sciences, GlaxoSmithKline; research funding from Eisai; travel, accommodations, expenses from Roche. Olivia Pagani: Participation in advisory boards for Roche, Eli Lilly, Novartis, Takeda, Pfizer, Debiopharm, Ipsen. Educational activity for Takeda, Pfizer, and Ipsen. Shani Paluch-Shimon: Speaker's bureau, honoraria, advisory board and consultancy for Roche, Pfizer, AstraZeneca, Novartis, Medison, Lilly. Elzbieta Senkus: Honoraria from Amgen, AstraZeneca, Cancérodigest, Clinigen, Curio Science, Egis, Eli Lilly, Genomic Health, Gilead, high5md, Novartis, Oncompass Medicine, Pfizer, Pierre Fabre, Roche, Sandoz, TLC Biopharmaceuticals; fees for travel support from Amgen, AstraZeneca, Egis, Novartis, Pfizer, and Roche; grants from Amgen, AstraZeneca, Eli Lilly, Novartis, Pfizer, Roche, and Samsung; stock from AstraZeneca, Eli Lilly, and Pfizer. Beat Thürlimann: Holds stock of Roche, Merck, and Novartis; advisory board member for Pierre Fabre, Pfizer, Roche, AstraZeneca, Eli Lilly; honoraria Oncogenomics, Daiichi Sankyo, Merck Sharp & Dohme, and InnoMedica. Khalil Zaman: Participation in advisory board or talk: AstraZeneca, Daiichi, Exact Sciences, Eli Lilly, Pierre Fabre, Gilead, Merck Sharp & Dohme, Novartis, Pfizer, Roche, Seagen, and Viatris/Mylan., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Invasive lobular breast cancer (ILC) is a special breast cancer (BC) subtype and is mostly hormone receptor (HR)-positive and ERBB2 non-amplified. Endocrine therapy restrains tumor proliferation and is the mainstay of lobular BC treatment. Mutation of ERBB2 has been associated with recurrent ILC. However, it is unknown whether ERBB2 mutation impacts on the otherwise exquisite responsiveness of early ILC to endocrine therapy. We have recently profiled n = 622 HR-positive early BCs from the ADAPT trial for mutations in candidate genes involved in endocrine resistance, including ERBB2. All patients were treated with short-term preoperative endocrine therapy (pET, tamoxifen or aromatase inhibitors) before tumor resection. Tumor proliferation after endocrine therapy (post-pET Ki67 index) was determined prospectively by standardized central pathology assessment supported by computer-assisted image analysis. Sustained or suppressed proliferation were defined as post-pET Ki67 ≥10% or <10%. Here, we report a subgroup analysis pertaining to ILCs in this cohort. ILCs accounted for 179/622 (28.8%) cases. ILCs were enriched in mutations in CDH1 (124/179, 69.3%, P < 0.0001) and ERBB2 (14/179, 7.8%, P < 0.0001), but showed fewer mutations in TP53 (7/179, 3.9%, P = 0.0048) and GATA3 (11/179, 6.1%, P < 0.0001). Considering all BCs irrespective of subtypes, ERBB2 mutation was not associated with proliferation. In ILCs, however, ERBB2 mutations were 3.5-fold more common in cases with sustained post-pET proliferation compared to cases with suppressed post-pET proliferation (10/75, 13.3% versus 4/104, 3.8%, P = 0.0248). Moreover, ERBB2 mutation was associated with high Oncotype DX recurrence scores (P = 0.0087). In summary, our findings support that ERBB2 mutation influences endocrine responsiveness in early lobular BC., (© 2022. The Author(s).)

We dedicate this manuscript in memory of a dear friend and colleague Bella Kaufman. The fifth International Consensus Symposium for Breast Cancer in Young Women (BCY5) took place virtually in October 2020, organized by the European School of Oncology (ESO) and the European Society of Medical Oncology (ESMO). Consensus recommendations for the management of breast cancer in young women were updated from BCY4 with incorporation of new evidence to inform the guidelines. Areas of research priorities as well as specificities in different geographic and minority populations were identified. This manuscript summarizes the ESO-ESMO international consensus recommendations, which are also endorsed by the European Society of Breast Specialists (EUSOMA)., Competing Interests: Disclosure SPS: Advisory Board consultancy, speaker's bureau: AstraZeneca, Pfizer, Novartis, Lilly, Roche, MSD, Exact Sciences. Research Funding: Pfizer. HAA: Recipient of grants/research supports: Amgen. Recipient of honoraria or consultation fees: Novartis, Roche. Employment: Pierre Fabre. FC: Recipient of honoraria or consultation fees: Amgen, Astellas/Medivation, AstraZeneca, Celgene, Daiichi-Sankyo, Eisai, GE Oncology, Genentech, GlaxoSmithKline, Macrogenics, Medscape, Merck-Sharp, Merus BV, Mylan, Mundipharma, Novartis, Pfizer, Pierre-Fabre, prIME Oncology, Roche, Samsung Bioepis. GC: Recipient of grants/research supports: Merck, Astra Zeneca. Recipient of honoraria or consultation fees: Daichii Sankyo. Participation in a sponsored speakers’ bureau: Novartis, Pfizer, Lilly. KAG: Recipient of grants/research supports: Pfizer, Astra Zeneca. Recipient of honoraria or consultation fees: Pfizer, Lilly, Astrazeneca, Novartis, Mylan, Benentech, Merck, Roche, Nanostring. NH: Honoraria for lectures and/or consulting from Amgen, Astra Zeneca, Daiichi-Sankyo, Exact Sciences, Lilly, MSD, Novartis, Pierre Fabre, Pfizer, Roche, Sandoz, Seagen (all outside the submitted work). SBK: Research funding from Novartis, Sanofi-Aventis and DongKook Pharm Co; consultant in advisory boards—Novartis, AstraZeneca, Lilly, Dae Hwa Pharmaceutical Co. Ltd, ISU Abxis, Daiichi-Sankyo and Beigene; and stocks—Genopeaks, NeogeneTC (all outside the submitted work). FP: Recipient of honoraria or consultation fees: Roche Diagnostics, Ipsen, Merck (all outside the submitted work). ES: Recipient of grants/research supports: Amgen, AstraZeneca, Boehringer, Eli Lilly, Merck, Novartis, Pfizer, Roche, Samsung. Recipient of honoraria or consultation fees: Amgen, AstraZeneca, Clinigen, Egis, Eli Lilly, Genomic Health, Novartis, Pfizer, Pierre Fabre, Roche, Sandoz, TLC Biopharmaceuticals. Travel support: Amgen, AstraZeneca, Egis, Novartis, Pfizer, Roche. All other authors have declared no conflicts of interest., (Copyright © 2022 European Society for Medical Oncology. Published by Elsevier Ltd. All rights reserved.)

There is a strong rationale for combining HER2-targeted therapies with cancer immunotherapy to increase efficacy in breast cancer, particularly in the early-stage setting, where the immune system has not been weakened by heavy pretreatment. ASTEFANIA aims to evaluate the efficacy of adjuvant atezolizumab in combination with ado-trastuzumab emtansine in patients with high-risk, HER2-positive early breast cancer and residual disease following HER2-based neoadjuvant therapy. Eligible patients will be randomized to receive ado-trastuzumab emtansine in combination with either atezolizumab or placebo for 14 cycles within 12 weeks of primary surgery. The primary outcome is invasive disease-free survival and secondary outcomes include additional efficacy end points, safety and pharmacokinetics. The study plans to enroll 1700 patients across 32 counties. Clinical Trial Registration: NCT04873362 (ClinicalTrials.gov).

Background: Higher density of stromal tumor-infiltrating lymphocytes (sTILs) at baseline has been associated with increased rates of pathological complete response (pCR) after neoadjuvant chemotherapy (NACT) in triple-negative breast cancer (TNBC). While evidence supports favorable association of pCR with survival in TNBC, an independent impact of sTILs (after adjustment for pCR) on survival is not yet established. Moreover, the impact of sTIL dynamics during NACT on pCR and survival in TNBC is unknown., Methods: The randomized WSG-ADAPT TN phase II trial compared efficacy of 12-week nab-paclitaxel with gemcitabine versus carboplatin. This preplanned translational analysis assessed impacts of sTIL measurements at baseline (sTIL-0) and after 3 weeks of chemotherapy (sTIL-3) on pCR and invasive disease-free survival (iDFS). Predictive performance of sTIL-0 and sTIL-3 for pCR was quantified by ROC analysis and logistic regression; Kaplan-Meier estimation and Cox regression (with mediation analysis) were used to determine their impact on iDFS., Results: For prediction of pCR, the AUC statistics for sTIL-0 and sTIL-3 were 0.60 and 0.63, respectively, in all patients; AUC for sTIL-3 was higher in NP/G. The positive predictive value (PPV) of "lymphocyte-predominant" status (sTIL-0 ≥ 60%) at baseline was 59.3%, though only 13.0% of patients had this status. To predict non-pCR, the cut point sTIL-0 ≤ 10% yielded PPV = 69.5% while addressing 33.8% of patients. Higher sTIL levels (particularly at 3 weeks) were independently and favorably associated with better iDFS, even after adjusting for pCR. For example, the adjusted hazard ratio for 3-week sTILs ≥ 60% (vs. < 60%) was 0.48 [0.23-0.99]. Low cellularity in 3-week biopsies was the strongest individual predictor for pCR (in both therapy arms), but not for iDFS., Conclusion: The independent impact of sTILs on iDFS suggests that favorable immune response can influence key tumor biological processes for long-term survival. The results suggest that the reliability of pCR following neoadjuvant therapy as a surrogate for survival could vary among subgroups in TNBC defined by immune response or other factors. Dynamic measurements of sTILs under NACT could support immune response-guided patient selection for individualized therapy approaches for both very low levels (more effective therapies) and very high levels (de-escalation concepts)., Trial Registration: Clinical trials No: NCT01815242, retrospectively registered January 25, 2013., (© 2022. The Author(s).)

It has been suggested that the benefit of adjuvant chemotherapy (CT) in premenopausal women with hormone receptor-positive (HR+), human epidermal growth factor receptor 2 negative (HER2-) early breast cancer may be related, at least in part, to CT-induced ovarian function suppression (OFS) in this subgroup of patients. Although this hypothesis has not been directly tested in large randomized clinical trials, the observations from prospective studies have been remarkably consistent in showing a late benefit of CT among the subgroup of patients who benefit (ie, women who were close to menopause). The hypothesis has important clinical implications, as it may be possible to spare the associated adverse effects of adjuvant CT in a select group of women with early breast cancer, in favor of optimizing OFS and endocrine therapy (ET), without compromising clinical outcomes. Such an approach has the added benefit of preserving the key quality of life outcomes in premenopausal women, particularly by preventing the irreversible loss of ovarian function that may result from CT use. For this reason, we convened an international panel of clinical experts in breast cancer treatment to discuss the key aspects of the available data in this area, as well as the potential clinical implications for patients. This article summarizes the results of these discussions and presents the consensus opinion of the panel regarding optimizing the use of OFS for premenopausal women with HR+, HER2- early breast cancer., (© The Author(s) 2022. Published by Oxford University Press.)

Purpose: To conduct an updated exploratory analysis of overall survival (OS) with a longer median follow-up of 73.3 months and evaluate the prognostic value of molecular analysis by circulating tumor DNA (ctDNA)., Patients and Methods: Patients with hormone receptor-positive/human epidermal growth factor receptor 2-negative (HR+/HER2-) advanced breast cancer (ABC) were randomized 2:1 to receive palbociclib (125 mg orally/day; 3/1 week schedule) and fulvestrant (500 mg intramuscularly) or placebo and fulvestrant. This OS analysis was performed when 75% of enrolled patients died (393 events in 521 randomized patients). ctDNA analysis was performed among patients who provided consent., Results: At the data cutoff (August 17, 2020), 258 and 135 deaths occurred in the palbociclib and placebo groups, respectively. The median OS [95% confidence interval (CI)] was 34.8 months (28.8-39.9) in the palbociclib group and 28.0 months (23.5-33.8) in the placebo group (stratified hazard ratio, 0.81; 95% CI, 0.65-0.99). The 6-year OS rate (95% CI) was 19.1% (14.9-23.7) and 12.9% (8.0-19.1) in the palbociclib and placebo groups, respectively. Favorable OS with palbociclib plus fulvestrant compared with placebo plus fulvestrant was observed in most subgroups, particularly in patients with endocrine-sensitive disease, no prior chemotherapy for ABC and low circulating tumor fraction and regardless of ESR1, PIK3CA, or TP53 mutation status. No new safety signals were identified., Conclusions: The clinically meaningful improvement in OS associated with palbociclib plus fulvestrant was maintained with >6 years of follow-up in patients with HR+/HER2- ABC, supporting palbociclib plus fulvestrant as a standard of care in these patients., (©2022 The Authors; Published by the American Association for Cancer Research.)

Purpose: To our knowledge, WSG-ADAPT-HR+/HER2- (ClinicalTrials.gov identifier: NCT01779206; n = 5,625 registered) is the first trial combining the 21-gene expression assay (recurrence score [RS]) and response to 3-week preoperative endocrine therapy (ET) to guide systemic therapy in early breast cancer., Materials and Methods: Baseline and postendocrine Ki67 (Ki67 post ) were evaluated centrally. In the endocrine trial, all patients received exclusively ET: patients with pathologic regional lymph node status (pN) 0-1 (ie, 0-3 involved lymph nodes) entered control arm if RS ≤ 11 and experimental arm if RS12-25 with ET response (Ki67 post ≤ 10%). All other patients (including N0-1 RS12-25 without ET response) received dose-dense chemotherapy (CT) followed by ET in the CT trial. Primary end point of the endocrine trial was noninferiority of 5-year invasive disease-free survival (5y-iDFS) in experimental ( v control) arm; secondary end points included distant DFS, overall survival, and translational research., Results: Intention-to-treat population comprised 2,290 patients (n = 1,422 experimental v n = 868 control): 26.3% versus 34.6% premenopausal and 27.4% versus 24.0% pN1. One-sided 95% lower confidence limit of the 5y-iDFS difference was -3.3%, establishing prespecified noninferiority ( P = .05). 5y-iDFS was 92.6% (95% CI, 90.8 to 94.0) in experimental versus 93.9% (95% CI, 91.8 to 95.4) in control arm; 5-year distant DFS was 95.6% versus 96.3%, and 5-year overall survival 97.3% versus 98.0%, respectively. Differences were similar in age and nodal subgroups. In N0-1 RS12-25, outcome of ET responders (ET alone) was comparable with that of ET nonresponders (CT) for age > 50 years and superior for age ≤ 50 years. ET response was more likely with aromatase inhibitors (mostly postmenopausal) than with tamoxifen (mostly premenopausal): 78.1% versus 41.1% ( P < .001). ET response was 78.8% in RS0-11, 62.2% in RS12-25, and 32.7% in RS > 25 (n = 4,203, P < .001)., Conclusion: WSG-ADAPT-HR+/HER2- demonstrates that guiding systemic treatment by both RS and ET response is feasible in clinical routine and spares CT in pre- and postmenopausal patients with ≤ 3 involved lymph nodes.

In intermediate risk hormone receptor (HR) positive, HER2 negative breast cancer (BC), the decision regarding adjuvant chemotherapy might be facilitated by multigene expression tests. In all, 142 intermediate risk BCs were investigated using the PAM50-based multigene expression test Prosigna® in a prospective multicentric study. In 119/142 cases, Prosigna® molecular subtyping was compared with local and two central (C1 and C6) molecular-like subtypes relying on both immunohistochemistry (IHC; HRs, HER2, Ki-67) and IHC + tumor grade (IHC+G) subtyping. According to local IHC, 35.4% were Luminal A-like and 64.6% Luminal B-like subtypes (local IHC+G subtype: 31.9% Luminal A-like; 68.1% Luminal B-like). In contrast to local and C1 subtyping, C6 classified >2/3 of cases as Luminal A-like. Pairwise agreement between Prosigna® subtyping and molecular-like subtypes was fair to moderate depending on molecular-like subtyping method and center. The best agreement was observed between Prosigna® (53.8% Luminal A; 44.5% Luminal B) and C1 surrogate subtyping (Cohen’s kappa = 0.455). Adjuvant chemotherapy was suggested to 44.2% and 88.6% of Prosigna® Luminal A and Luminal B cases, respectively. Out of all Luminal A-like cases (locally IHC/IHC+G subtyping), adjuvant chemotherapy was recommended if Prosigna® testing classified as Prosigna® Luminal A at high / intermediate risk or upgraded to Prosigna® Luminal B.

Background: Among breast cancers without human epidermal growth factor receptor 2 (HER2) amplification, overexpression, or both, a large proportion express low levels of HER2 that may be targetable. Currently available HER2-directed therapies have been ineffective in patients with these "HER2-low" cancers., Methods: We conducted a phase 3 trial involving patients with HER2-low metastatic breast cancer who had received one or two previous lines of chemotherapy. (Low expression of HER2 was defined as a score of 1+ on immunohistochemical [IHC] analysis or as an IHC score of 2+ and negative results on in situ hybridization.) Patients were randomly assigned in a 2:1 ratio to receive trastuzumab deruxtecan or the physician's choice of chemotherapy. The primary end point was progression-free survival in the hormone receptor-positive cohort. The key secondary end points were progression-free survival among all patients and overall survival in the hormone receptor-positive cohort and among all patients., Results: Of 557 patients who underwent randomization, 494 (88.7%) had hormone receptor-positive disease and 63 (11.3%) had hormone receptor-negative disease. In the hormone receptor-positive cohort, the median progression-free survival was 10.1 months in the trastuzumab deruxtecan group and 5.4 months in the physician's choice group (hazard ratio for disease progression or death, 0.51; P<0.001), and overall survival was 23.9 months and 17.5 months, respectively (hazard ratio for death, 0.64; P = 0.003). Among all patients, the median progression-free survival was 9.9 months in the trastuzumab deruxtecan group and 5.1 months in the physician's choice group (hazard ratio for disease progression or death, 0.50; P<0.001), and overall survival was 23.4 months and 16.8 months, respectively (hazard ratio for death, 0.64; P = 0.001). Adverse events of grade 3 or higher occurred in 52.6% of the patients who received trastuzumab deruxtecan and 67.4% of those who received the physician's choice of chemotherapy. Adjudicated, drug-related interstitial lung disease or pneumonitis occurred in 12.1% of the patients who received trastuzumab deruxtecan; 0.8% had grade 5 events., Conclusions: In this trial involving patients with HER2-low metastatic breast cancer, trastuzumab deruxtecan resulted in significantly longer progression-free and overall survival than the physician's choice of chemotherapy. (Funded by Daiichi Sankyo and AstraZeneca; DESTINY-Breast04 ClinicalTrials.gov number, NCT03734029.)., (Copyright © 2022 Massachusetts Medical Society.)