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Purpose: NCI-MATCH assigned patients with advanced cancer and progression on prior treatment, based on genomic alterations in pretreatment tumor tissue. Arm J (EAY131-J) evaluated the combination of trastuzumab/pertuzumab (HP) across HER2-amplified tumors., Patients and Methods: Eligible patients had high levels of HER2 amplification [copy number (CN) ≥7] detected by central next-generation sequencing (NGS) or through NCI-designated laboratories. Patients with breast/gastroesophageal adenocarcinoma and those who received prior HER2-directed therapy were excluded. Enrollment of patients with colorectal cancer was capped at 4 based on emerging data. Patients received HP IV Q3 weeks until progression or unacceptable toxicity. Primary endpoint was objective response rate (ORR); secondary endpoints included progression-free survival (PFS) and overall survival (OS)., Results: Thirty-five patients were enrolled, with 25 included in the primary efficacy analysis (CN ≥7 confirmed by a central lab, median CN = 28). Median age was 66 (range, 31-80), and half of all patients had ≥3 prior therapies (range, 1-11). The confirmed ORR was 12% [3/25 partial responses (colorectal, cholangiocarcinoma, urothelial cancers), 90% confidence interval (CI) 3.4%-28.2%]. There was one additional partial response (urothelial cancer) in a patient with an unconfirmed ERBB2 copy number. Median PFS was 3.3 months (90% CI 2.0-4.1), and median OS 9.4 months (90% CI 5.0-18.9). Treatment-emergent adverse events were consistent with prior studies. There was no association between HER2 CN and response., Conclusions: HP was active in a selection of HER2-amplified tumors (non-breast/gastroesophageal) but did not meet the predefined efficacy benchmark. Additional strategies targeting HER2 and potential resistance pathways are warranted, especially in rare tumors., (©2024 American Association for Cancer Research.)

Background: Activation of leukemia inhibitory factor (LIF) is linked to an immunosuppressive tumor microenvironment (TME), with a strong association between LIF expression and tumor-associated macrophages (TAMs). MSC-1 (AZD0171) is a humanized monoclonal antibody that binds with high affinity to LIF, promoting antitumor inflammation through TAM modulation and cancer stem cell inhibition, slowing tumor growth. In this phase I, first-in-human, open-label, dose-escalation study, MSC-1 monotherapy was assessed in patients with advanced, unresectable solid tumors., Materials and Methods: Using accelerated-titration dose escalation followed by a 3 + 3 design, MSC-1 doses of 75-1500 mg were administered intravenously every 3 weeks (Q3W) until progression or unmanageable toxicity. Additional patients were enrolled in selected cohorts to further evaluate safety, pharmacokinetics (PK), and pharmacodynamics after escalation to the next dose had been approved. The primary objective was characterizing safety and determining the recommended phase II dose (RP2D). Evaluating antitumor activity and progression-free survival (PFS) by RECIST v1.1, PK and immunogenicity were secondary objectives. Exploratory objectives included pharmacodynamic effects on circulating LIF and TME immune markers., Results: Forty-one patients received treatment. MSC-1 monotherapy was safe and well tolerated at all doses, with no dose-limiting toxicities. The maximum tolerated dose was not reached and the RP2D was determined to be 1500 mg Q3W. Almost half of the patients had treatment-related adverse events (TRAEs), with no apparent trends across doses; no patients withdrew due to TRAEs. There were no objective responses; 23.7% had stable disease for ≥2 consecutive tumor assessments. Median PFS was 5.9 weeks; 23.7% had PFS >16 weeks. On-treatment changes in circulating LIF and TME signal transducers and activators of transcription 3 signaling, M1:M2 macrophage populations, and CD8+ T-cell infiltration were consistent with the hypothesized mechanism of action., Conclusions: MSC-1 was very well tolerated across doses, with prolonged PFS in some patients. Biomarker and preclinical data suggest potential synergy with checkpoint inhibitors., Competing Interests: Disclosure EB has provided advisory work for BioNTech SE and Imaging Endpoints LLC, and has participated in a speaker’s bureau for Ipsen. AMS has received fees and/or research grants from AstraZeneca, Northern Biologics, Merus, Kura Oncology, Surface Oncology, Lilly Oncology, Pfizer, Black Diamond Therapeutics, BeiGene, and Relay Therapeutics. EG has received personal fees for a consultant/advisory role from Janssen, Seattle Genetics, TFS HealthScience, Alkermes, Thermo Fisher Scientific, Bristol Myers Squibb, and MSD; and research grants from Menarini Diagnostics and Glycotope Biotechnology GmbH. IB has received research funding from Northern Biologics, AstraZeneca, Boehringer Ingelheim, Bristol Myers Squibb, Celgene, MSD, Novartis, OrionPharma, Regeneron, Seattle Genetics, Shattuck Labs, and VCN Biosciences SL; institutional grants from Cellex Foundation, La Caixa Foundation, and Banco Bilbao Vizcaya Argentaria Foundation (BBVA Foundation); educational grants from Bristol Myers Squibb; consulting fees from Achilles Therapeutics PLC, Bristol Myers Squibb, Cancer Expert Now, Etherna Immunotherapies Nv, Merck Serono, MSD, and Rakuten; payment of honoraria from Bristol Myers Squibb, Merck Serono, and MSD; support from attending meetings and/or travel from Merck Serono and MSD; and has a leadership or fiduciary role in another board, society, committee, or advocacy group, paid or unpaid, with ESMO Head and Neck track, EORTC Head and Neck group, and Cancer Core Europe Clinical Taskforce. MVV has received personal fees from Roche outside the work submitted. AS has received research funding from AstraZeneca, Northern Biologics, Alkermes, Array BioPharma/Pfizer, Bayer, Bristol Myers Squibb, GlaxoSmithKline, Janssen Oncology/Johnson & Johnson, Merck, Novartis, Regeneron Pharmaceuticals, Roche, Surface Oncology, Symphogen, Treadwell Therapeutics, and Oncorus; and personal fees from Bristol Myers Squibb, Merck, and Oncorus. MO has received personal fees from Bristol Myers Squibb, Merck, and MSD; non-financial support from Bristol Myers Squibb and MSD; and research grants from the Spanish Society of Medical Oncology, CRIS Contra el Cancer Foundation, and ASO Conquer Cancer Foundation, all outside of the work submitted. NJL has received honoraria for advisory boards from Innovent Biologics; and research funding from AstraZeneca, Northern Biologics, Alpine Immune Sciences, ALX Oncology, Apexian Pharmaceuticals, Ascentage Pharma, Alexion Pharmaceuticals, Asana, BeiGene, CytomX, Constellation Pharmaceutical, Cerulean Pharma, Formation Biologics (Forbius), Forty Seven, Ikena Oncology, Incyte Corporation, Inhibrx, Innovent Biologics, Jounce Therapeutics, Merck, Mersana Therapeutics, Pfizer, Regeneron Pharmaceuticals, Symphogen, and TaiRx. KH is a former employee and holds shares of Northern Biologics. RMH is a former employee and holds shares of Northern Biologics. DM is a former employee and holds shares of Northern Biologics. FH has received funding from Northern Biologics for the present work as part of Applied BioMath. JH has received funding from Northern Biologics for the present work as part of Applied BioMath; and owns shares of Pfizer. PG is a former employee and holds shares of Northern Biologics. JA is a former employee and holds shares of Northern Biologics. AK was a consultant to Northern Biologics at the time the study was conducted. PJV is a former employee and holds shares of Northern Biologics. RW is a former employee and holds shares of Northern Biologics. JS is a co-founder of Mosaic Biomedicals and has ownership interests from Mosaic Biomedicals and Northern Biologics; and had received grant/research support from Mosaic Biomedicals, Northern Biologics, Roche Glycart AG, and F. Hoffmann-La Roche Ltd. LLS has received financial compensation for consulting/advisory work from Merck, Pfizer, Celgene, AstraZeneca, Morphosys, Roche, GeneSeeq, Loxo Oncology, Oncorus, Symphogen, Seattle Genetics, GlaxoSmithKline, Voronoi, Treadwell Therapeutics, Arvinas, Tessa Therapeutics, Navire Pharma, Relay Therapeutics, and Rubius Therapeutics; and research grants/support from Novartis, Bristol Myers Squibb, Pfizer, Boehringer Ingelheim, GlaxoSmithKline, Roche/Genentech, Karyopharm, AstraZeneca, Merck, Celgene, Astellas, AbbVie, Amgen, Symphogen, Intensity Therapeutics, Mirati Therapeutics, Shattuck Labs, and Avid Radiopharmaceuticals. DMH is an employee of Loxo Oncology at Lilly, a wholly owned subsidiary of Eli Lilly (salary and equity). DVH is an employee of McKesson Corporation; he has stock or other ownership interests in Medtronic, CerRx, SynDevRx, UnitedHealthcare, Anthem Inc, Stromatis Pharma, Systems Oncology, StingRay Therapeutics, Forma Therapeutics, and Orpheus Bioscience; he has received financial compensation for consulting/advisory work from DNAtrix, Esperance Pharmaceuticals, Five Prime Therapeutics, Imaging Endpoints, Medical Prognosis Institute, Senhwa Biosciences, Tolero Pharmaceuticals, Alpha Cancer Technologies, Arvinas, Bellicum Pharmaceuticals, CanBas, Horizon Discovery, Lixte Biotechnology, Oncolyze, Translational Drug Development (TD2), Aadi Bioscience, Aptose Biosciences, BiolineRx, CytomX Therapeutics, EMD Serono, Evelo Biosciences, Fujifilm, Kura Oncology, Phosplatin Therapeutics, Sotio, Strategia Therapeutics, Synergene Therapeutics, 7 Hills Pharma, Actinium Pharmaceuticals, Cancer Prevention Pharmaceuticals, Geistlich Pharma, Huya Bioscience International, Immunophotonics, Genzada Pharmaceuticals, L.E.A.F. Pharmaceuticals, Oncology Venture, Turning Point Therapeutics, Verily Life Sciences, Athenex, Samus Therapeutics, Aeglea Biotherapeutics, Novita Pharmaceuticals, NuCana, Vicus Therapeutics, Codiak Biosciences, Agenus, Kelun, Radimmune Therapeutics, Samumed, Sobi, BioXcel therapeutics, Bryologyx, Celgene, BioPharma Services, Sirnaomics, AIMed, Boston Scientific, Corcept Therapeutics, Erimos Pharmaceuticals, Gimbal Bio, Amunix Pharmaceuticals, Pfizer, Apeiron Biologics, GiraFpharma, Axis Therapeutics, DrugCendR, ImmuneOncia, Orphagen Pharmaceuticals, Array BioPharma, MaveriX Oncology, Northern Biologics, Viracta Therapeutics, Varian Biopharma, Xerient Pharma, AlaMab Therapeutics, Avesta76 Therapeutics, Bessor Pharma, NeoTx, Decoy Biosystems, Noxxon Pharma, RefleXion Medical, and Reglagene; and has received research grants/support from Eli Lilly, Genentech, Celgene, Incyte, Merrimack Pharmaceuticals, Plexxikon, Minneamrita Therapeutics, AbbVie, Aduro Biotech, Cleave Biosciences, CytRx Corporation, Daiichi Sankyo, Deciphera Pharmaceuticals, Endocyte, Exelixis, Five Prime Therapeutics, Gilead Sciences, Merck, Pfizer, Pharmacyclics, Phoenix Biotechnology, Samumed, Strategia Therapeutics, and Halozyme. JT reports personal financial interests in the form of scientific consultancy role for Array BioPharma, AstraZeneca, Bayer, Boehringer Ingelheim, Chugai, Daiichi Sankyo, F. Hoffmann-La Roche Ltd, Genentech, Inc., HalioDx SAS, Hutchison MediPharma, Ikena Oncology, IQVIA, Lilly, Menarini, Merck Serono, Merus, MSD, Mirati Therapeutics, Inc., NeoPhore, Novartis, Orion Biotechnology, Peptomyc SL, Pfizer, Pierre Fabre, Samsung Bioepis, Sanofi, Seattle Genetics, Servier, Taiho Pharmaceutical, Tessa Therapeutics, and TheraMyc Limited., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Purpose: We wanted to determine the prognosis and the phenotypic characteristics of hormone receptor-positive advanced breast cancer tumors harboring an ERBB2 mutation in the absence of a HER2 amplification., Experimental Design: We retrospectively collected information from the American Association of Cancer Research-Genomics Evidence Neoplasia Information Exchange registry database from patients with hormone receptor-positive, HER2-negative, ERBB2-mutated advanced breast cancer. Phenotypic and co-mutational features, as well as response to treatment and outcome were compared with matched control cases ERBB2 wild type., Results: A total of 45 ERBB2-mutant cases were identified for 90 matched controls. The presence of an ERBB2 mutation was not associated with worse outcome determined by overall survival (OS) from first metastatic relapse. No significant differences were observed in phenotypic characteristics apart from higher lobular infiltrating subtype in the ERBB2-mutated group. ERBB2 mutation did not seem to have an impact in response to treatment or time-to-progression (TTP) to endocrine therapy compared with ERBB2 wild type. In the co-mutational analyses, CDH1 mutation was more frequent in the ERBB2-mutated group (FDR < 1). Although not significant, fewer co-occurring ESR1 mutations and more KRAS mutations were identified in the ERBB2-mutated group., Conclusions: ERBB2-activating mutation was not associated with a worse OS from time of first metastatic relapse, or differences in TTP on treatment as compared with a series of matched controls. Although not significant, differences in coexisting mutations (CDH1, ESR1, and KRAS) were noted between the ERBB2-mutated and the control group., (©2022 American Association for Cancer Research.)

AKT- a key molecular regulator of PI-3K signaling pathway, is somatically mutated in diverse solid cancer types, and aberrant AKT activation promotes altered cancer cell growth, survival, and metabolism 1-8 . The most common of AKT mutations (AKT1 E17K) sensitizes affected solid tumors to AKT inhibitor therapy 7,8 . However, the pathway dependence and inhibitor sensitivity of the long tail of potentially activating mutations in AKT is poorly understood, limiting our ability to act clinically in prospectively characterized cancer patients. Here we show, through population-scale driver mutation discovery combined with functional, biological, and therapeutic studies that some but not all missense mutations activate downstream AKT effector pathways in a growth factor-independent manner and sensitize tumor cells to diverse AKT inhibitors. A distinct class of small in-frame duplications paralogous across AKT isoforms induce structural changes different than those of activating missense mutations, leading to a greater degree of membrane affinity, AKT activation, and cell proliferation as well as pathway dependence and hyper-sensitivity to ATP-competitive, but not allosteric AKT inhibitors. Assessing these mutations clinically, we conducted a phase II clinical trial testing the AKT inhibitor capivasertib (AZD5363) in patients with solid tumors harboring AKT alterations (NCT03310541). Twelve patients were enrolled, out of which six harbored AKT1-3 non-E17K mutations. The median progression free survival (PFS) of capivasertib therapy was 84 days (95% CI 50-not reached) with an objective response rate of 25% (n = 3 of 12) and clinical benefit rate of 42% (n = 5 of 12). Collectively, our data indicate that the degree and mechanism of activation of oncogenic AKT mutants vary, thereby dictating allele-specific pharmacological sensitivities to AKT inhibition., (© 2022. The Author(s).)

The efficacy of the highly selective RET inhibitor selpercatinib is now established in RET-driven cancers, and we sought to characterize the molecular determinants of response and resistance. We find that the pre-treatment genomic landscape does not shape the variability of treatment response except for rare instances of RAS-mediated primary resistance. By contrast, acquired selpercatinib resistance is driven by MAPK pathway reactivation by one of two distinct routes. In some patients, on- and off-target pathway reactivation via secondary RET solvent front mutations or MET amplifications are evident. In other patients, rare RET-wildtype tumor cell populations driven by an alternative mitogenic driver are selected for by treatment. Multiple distinct mechanisms are often observed in the same patient, suggesting polyclonal resistance may be common. Consequently, sequential RET-directed therapy may require combination treatment with inhibitors targeting alternative MAPK effectors, emphasizing the need for prospective characterization of selpercatinib-treated tumors at the time of monotherapy progression., (© 2022. The Author(s).)

Background: Covalent (irreversible) Bruton's tyrosine kinase (BTK) inhibitors have transformed the treatment of multiple B-cell cancers, especially chronic lymphocytic leukemia (CLL). However, resistance can arise through multiple mechanisms, including acquired mutations in BTK at residue C481, the binding site of covalent BTK inhibitors. Noncovalent (reversible) BTK inhibitors overcome this mechanism and other sources of resistance, but the mechanisms of resistance to these therapies are currently not well understood., Methods: We performed genomic analyses of pretreatment specimens as well as specimens obtained at the time of disease progression from patients with CLL who had been treated with the noncovalent BTK inhibitor pirtobrutinib. Structural modeling, BTK-binding assays, and cell-based assays were conducted to study mutations that confer resistance to noncovalent BTK inhibitors., Results: Among 55 treated patients, we identified 9 patients with relapsed or refractory CLL and acquired mechanisms of genetic resistance to pirtobrutinib. We found mutations (V416L, A428D, M437R, T474I, and L528W) that were clustered in the kinase domain of BTK and that conferred resistance to both noncovalent BTK inhibitors and certain covalent BTK inhibitors. Mutations in BTK or phospholipase C gamma 2 (PLCγ2), a signaling molecule and downstream substrate of BTK, were found in all 9 patients. Transcriptional activation reflecting B-cell-receptor signaling persisted despite continued therapy with noncovalent BTK inhibitors., Conclusions: Resistance to noncovalent BTK inhibitors arose through on-target BTK mutations and downstream PLCγ2 mutations that allowed escape from BTK inhibition. A proportion of these mutations also conferred resistance across clinically approved covalent BTK inhibitors. These data suggested new mechanisms of genomic escape from established covalent and novel noncovalent BTK inhibitors. (Funded by the American Society of Hematology and others.)., (Copyright © 2022 Massachusetts Medical Society.)

Neurotrophic tyrosine receptor kinase (NTRK) gene fusions lead to chimeric tropomyosin receptor kinase (TRK) fusion proteins, which act as primary oncogenic drivers in diverse tumor types in adults and children. Larotrectinib, a highly selective and central nervous system-active TRK inhibitor, has shown high objective response rates, durable disease control, and a favorable safety profile in patients with TRK fusion cancer. The impact of larotrectinib on health-related quality of life (HRQoL) was evaluated in adult and pediatric patients in two phase I/II clinical trials (NAVIGATE; NCT02576431 and SCOUT; NCT02637687). Patients completed HRQoL questionnaires (EORTC QLQ-C30, EQ-5D-5L, and PedsQL) at baseline and at planned treatment cycle visits. Changes in questionnaire scores were evaluated over time, and by tumor type and treatment response. Questionnaires from 40 adult and 17 pediatric (2-19 years of age) patients receiving larotrectinib were completed at baseline and at least one post-baseline timepoint. Meaningful within-patient HRQoL improvements occurred at one or more timepoints in 60% of adults and 76% of pediatric patients. Sustained improvements in EORTC QLQ-C30 and PedsQL scores were rapid, occurring within 2 months of treatment initiation in 68% and 71% of patients, respectively. Improvements were observed regardless of tumor type and appeared to correlate with clinical efficacy. The rapid within-patient HRQoL improvements in adult and pediatric patients with TRK fusion cancer are consistent with the clinical profile of larotrectinib. Our results provide valuable information for use of this agent in this patient population. A plain language summary of this article is available in the supplementary appendix., Competing Interests: Conflict of Interest SK discloses an advisory role, honoraria, and travel support from Bayer. JB discloses research funding from PsiOxus, Bayer, EMD Serono, Symphogen, Roche/Genentech, and Immunomed; honoraria from Nestle; and consulting/advisory roles with Rafeal, Seattle Genetics, EMD Serono, Bayer, Eisai, Taiho, Armo, Gritstone, AstraZeneca, Celgene, and Erytech. LM discloses a speaker bureau role for Bayer. CMvT discloses advisory roles for Bayer and Novartis. UNL discloses an advisory role for Bayer. RJS discloses consulting/advisory roles for Celsion, Clovis, Incyte, Flatiron Health, and Immunogen. KK and BHC are employees of Bayer HealthCare. SN was an employee of Bayer HealthCare at the time this work was conducted. CC is an employee of RTI International. TWL discloses consultancy for Novartis, Bayer, Loxo Oncology, and Lilly; and research funding from Pfizer, Novartis, Bayer, Loxo Oncology, Abbvie, Amgen, Atara, Biotherapeutics, BMS, Lilly, Epizyme, GSK, Janssen, Jubilant Pharmaceuticals, Novella Clinical, and Servier. DMH discloses consulting/advisory roles with Chugai Pharma, CytomX Therapeutics, Boehringer Ingelheim, AstraZeneca, Pfizer, Bayer, and Genentech; research funding from AstraZeneca, Puma Biotechnology, Loxo Oncology, and Bayer; and travel/accommodation/expenses from Genentech and Chugai Pharma. AD discloses honoraria/advisory roles with Ignyta/Genentech/Roche, Loxo Oncology/Bayer/Lilly, Takeda/Ariad/Millenium, TP Therapeutics, AstraZeneca, Pfizer, Blueprint Medicines, Helsinn, Beigene, BergenBio, Hengrui Therapeutics, Exelixis, Tyra Biosciences, Verastem, and MORE Health; associated research paid to institution from Pfizer, Exelixis, GlaxoSmithKline, Teva, Taiho, and PharmaMar; research with Foundation Medicine; royalties from Wolters Kluwer; food/beverages from Merck and Puma Biotechnology; and CME honoraria from Medscape, OncLive, PeerVoice, Physicians Education Resources, Targeted Oncology, and Research to Practice. DSH discloses research/grant funding from AbbVie, Adaptimmune, Amgen, AstraZeneca, Bayer, BMS, Daiichi-Sankyo, Eisai, Fate Therapeutics, Genentech, Genmab, Ignyta, Infinity, Kite, Kyowa, Lilly, Loxo Oncology, Merck, MedImmune, Mirati, MiRNA, Molecular Templates, Mologen, NCI-CTEP, Novartis, Pfizer, Seattle Genetics, and Takeda; travel/accommodation/expenses from Loxo Oncology, MiRNA, ASCO, AACR, SITC, and Genmab; consulting/advisory roles for Alpha Insights, Axiom, Adaptimmune, Baxter, Bayer, Genentech, GLG, Group H, Guidepoint Global, Infinity, Janssen, Merrimack, Medscape, Numab, Pfizer, Seattle Genetics, Takeda, and Trieza Therapeutics; and ownership interests in Molecular Match (advisor), OncoResponse (founder) and Presagia Inc (Advisor). BT and BG have nothing to disclose., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

Human cancers arise from environmental, heritable and somatic factors, but how these mechanisms interact in tumorigenesis is poorly understood. Studying 17,152 prospectively sequenced patients with cancer, we identified pathogenic germline variants in cancer predisposition genes, and assessed their zygosity and co-occurring somatic alterations in the concomitant tumors. Two major routes to tumorigenesis were apparent. In carriers of pathogenic germline variants in high-penetrance genes (5.1% overall), lineage-dependent patterns of biallelic inactivation led to tumors exhibiting mechanism-specific somatic phenotypes and fewer additional somatic oncogenic drivers. Nevertheless, 27% of cancers in these patients, and most tumors in patients with pathogenic germline variants in lower-penetrance genes, lacked particular hallmarks of tumorigenesis associated with the germline allele. The dependence of tumors on pathogenic germline variants is variable and often dictated by both penetrance and lineage, a finding with implications for clinical management., (© 2021. The Author(s), under exclusive licence to Springer Nature America, Inc.)

Purpose: This was a multicenter, histology-agnostic, single-arm prospective phase II trial of therapeutic activity of everolimus, an oral mTORC1 inhibitor, in patients with advanced solid tumors that harbored TSC1 / TSC2 or MTOR mutations., Patients and Methods: Patients with tumors with inactivating TSC1 / TSC2 or activating MTOR mutations identified in any Clinical Laboratory Improvement Amendments (CLIA)-certified laboratory were eligible. Patients were treated with everolimus 10 mg once daily until disease progression or unacceptable toxicity. The primary endpoint was objective response rate (ORR). Whole-exome sequencing was performed to identify co-occurring genomic alterations., Results: Between November 2015 and October 2018, 30 patients were enrolled at Dana-Farber Cancer Institute and Memorial Sloan Kettering Cancer Center. Tumors harbored TSC1 (13/30), TSC2 (15/30), concurrent TSC1 and TSC2 (1/30), or MTOR (1/30) mutations. The most common treatment-related adverse event of any grade was mucositis (8/30, 27%); 1 patient had fatal pneumonitis. Partial responses were seen in 2 patients [7%; 95% confidence interval (CI), 1%-22%]. Median progression-free survival was 2.3 months (95% CI, 1.8-3.7 months) and median overall survival (OS) was 7.3 months (95% CI, 4.5-12.7 months). There was no clear association between other genomic alterations and response. Of the 2 patients with objective response, 1 had upper tract urothelial carcinoma with biallelic inactivation of TSC1 and high tumor mutation burden, and the other had uterine carcinoma with biallelic TSC2 -inactivating mutations and PEComa-like pathologic features., Conclusions: Everolimus therapy had a disappointing ORR (7%) in this pan-cancer, mutation-selected, basket study. See related commentary by Kato and Cohen, p. 3807 ., (©2021 American Association for Cancer Research.)

Background Ulixertinib is the first-in-class ERK1/2 kinase inhibitor with encouraging clinical activity in BRAF- and NRAS-mutant cancers. Dermatologic adverse events (dAEs) are common with ulixertinib, so management guidelines like those established for epidermal growth factor receptor inhibitor (EGFRi)-associated dAEs are needed. Patients and Methods This was an open-label, multicenter, phase I dose escalation and expansion trial of ulixertinib evaluating data from 135 patients with advanced malignancies enrolled between March 2013 and July 2017. Histopathological features, management, and dAEs in 34 patients are also reported. Twice daily oral ulixertinib was administered at 10 to 900 mg in the dose escalation cohort (n = 27) and at 600 mg in 21-day cycles in the expansion cohort (n = 108). Results The incidence of ulixertinib-induced dAEs and combined rash were 79% (107/135) and 76% (102/135). The most common dAEs included acneiform rash (45/135, 33%), maculopapular rash (36/135, 27%), and pruritus (34/135, 25%). Grade 3 dAEs were observed in 19% (25/135) of patients; no grade 4 or 5 dAEs were seen. The presence of at least 1 dAE was associated with stable disease (SD) or partial response (PR) (OR = 3.64, 95% CI 1.52-8.72; P = .003). Acneiform rash was associated with a PR (OR = 10.19, 95% CI 2.67-38.91; P < .001). Conclusion The clinical spectrum of ulixertinib-induced dAEs was similar to EGFR and MEK inhibitors; dAEs may serve as a surrogate marker of tumor response. We propose treatment algorithms for common ERK inhibitor-induced dAEs to maintain patients' quality of life and dose intensity for maximal clinical benefit. Clinical Trial Registration: NCT01781429.

Five to ten percent of ER+ metastatic breast cancer (MBC) tumors harbor somatic PTEN mutations. Loss of function of this tumor-suppressor gene defines a highly aggressive, treatment-refractory disease for which new therapies are urgently needed. This Phase I multipart expansion study assessed oral capivasertib with fulvestrant in patients with PTEN-mutant ER+ MBC. Safety and tolerability were assessed by standard methods. Plasma and tumor were collected for NGS and immunohistochemistry analyses of PTEN protein expression. In 31 eligible patients (12 fulvestrant naive; 19 fulvestrant pretreated), the 24-week clinical benefit rate was 17% in fulvestrant-naive and 42% in fulvestrant-pretreated patients, with objective response rate of 8% and 21%, respectively. Non-functional PTEN was centrally confirmed in all cases by NGS or immunohistochemistry. Co-mutations occurred in PIK3CA (32%), with less ESR1 (10% vs 72%) and more TP53 (40% vs 28%) alterations in fulvestrant-naive versus fulvestrant-pretreated patients, respectively. PTEN was clonally dominant in most patients. Treatment-related grade ≥3 adverse events occurred in 32% of patients, most frequently diarrhea and maculopapular rash (both n = 2). In this clinical study, which selectively targeted the aggressive PTEN-mutant ER+ MBC, capivasertib plus fulvestrant was tolerable and clinically active. Phenotypic and genomic differences were apparent between fulvestrant-naive and -pretreated patients.Trial registration number for the study is NCT01226316.

Purpose: Somatic mutations in phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha ( PIK3CA ), which encodes the p110α catalytic subunit of PI3K, are found in multiple human cancers. While recurrent mutations in PIK3CA helical, regulatory, and kinase domains lead to constitutive PI3K pathway activation, other mutations remain uncharacterized. To further evaluate their clinical actionability, we designed a basket study for patients with PIK3CA -mutant cancers with the isoform-specific PI3K inhibitor taselisib., Patients and Methods: Patients were enrolled on the basis of local PIK3CA mutation testing into one of 11 histology-specific cohorts and treated with taselisib at 6 or 4 mg daily until progression. Tumor DNA from baseline and progression (when available) was sequenced using a next-generation sequencing panel. Exploratory analyses correlating genomic alterations with treatment outcomes were performed., Results: A total of 166 patients with PIK3CA -mutant cancers were enrolled. The confirmed response rate was 9%. Activity varied by tumor type and mutant allele, with confirmed responses observed in head and neck squamous (15.4%), cervical (10%), and other cancers, plus in tumors containing helical domain mutations. Genomic analyses identified mutations potentially associated with resistance to PI3K inhibition upfront ( TP53 and PTEN ) and postprogression through reactivation of the PI3K pathway ( PTEN, STK11 , and PIK3R1 ). Higher rates of dose modification occurred at higher doses of taselisib, indicating a narrow therapeutic index., Conclusions: Taselisib had limited activity in the tumor types tested and is no longer in development. This genome-driven study improves understanding of the activity, limitations, and resistance mechanisms of using PI3K inhibitors as monotherapy to target PIK3CA -mutant tumors., (©2020 American Association for Cancer Research.)

Purpose: Cell-free DNA (cfDNA) analysis offers a noninvasive means to access the tumor genome. Despite limited sensitivity of broad-panel sequencing for detecting low-frequency mutations in cfDNA, it may enable more comprehensive genomic characterization in patients with sufficiently high disease burden. We investigated the utility of large-panel cfDNA sequencing in patients enrolled to a Phase I AKT1 -mutant solid tumor basket study., Methods: Patients had AKT1 E17K-mutant solid tumors and were treated on the multicenter basket study (ClinicalTrials.gov identifier: NCT01226316) of capivasertib, an AKT inhibitor. Serial plasma samples were prospectively collected and sequenced using exon-capture next-generation sequencing (NGS) analysis of 410 genes (Memorial Sloan Kettering [MSK]-Integrated Molecular Profiling of Actionable Cancer Target [IMPACT]) and allele-specific droplet digital polymerase chain reaction (ddPCR) for AKT1 E17K. Tumor DNA (tDNA) NGS (MSK-IMPACT) was also performed on available pretreatment tissue biopsy specimens., Results: Among 25 patients, pretreatment plasma samples were sequenced to an average coverage of 504×. Somatic mutations were called in 20/25 (80%), with mutant allele fractions highly concordant with ddPCR of AKT1 E17K ( r 2 = 0.976). Among 17 of 20 cfDNA-positive patients with available tDNA for comparison, mutational concordance was acceptable, with 82% of recurrent mutations shared between tissue and plasma. cfDNA NGS captured additional tumor heterogeneity, identifying mutations not observed in tDNA in 38% of patients, and revealed oncogenic mutations in patients without available baseline tDNA. Longitudinal cfDNA NGS (n = 98 samples) revealed distinct patterns of clonal dynamics in response to therapy., Conclusion: Large gene panel cfDNA NGS is feasible for patients with high disease burden and is concordant with single-analyte approaches, providing a robust alternative to ddPCR with greater breadth. cfDNA NGS can identify heterogeneity and potentially biologically informative and clinically relevant alterations., (© 2021 by American Society of Clinical Oncology.)

On-target resistance to next-generation TRK inhibitors in TRK fusion-positive cancers is largely uncharacterized. In patients with these tumors, we found that TRK xDFG mutations confer resistance to type I next-generation TRK inhibitors designed to maintain potency against several kinase domain mutations. Computational modeling and biochemical assays showed that TRKA G667 and TRKC G696 xDFG substitutions reduce drug binding by generating steric hindrance. Concurrently, these mutations stabilize the inactive (DFG-out) conformations of the kinases, thus sensitizing these kinases to type II TRK inhibitors. Consistently, type II inhibitors impede the growth and TRK-mediated signaling of xDFG-mutant isogenic and patient-derived models. Collectively, these data demonstrate that adaptive conformational resistance can be abrogated by shifting kinase engagement modes. Given the prior identification of paralogous xDFG resistance mutations in other oncogene-addicted cancers, these findings provide insights into rational type II drug design by leveraging inhibitor class affinity switching to address recalcitrant resistant alterations. SIGNIFICANCE: In TRK fusion-positive cancers, TRK xDFG substitutions represent a shared liability for type I TRK inhibitors. In contrast, they represent a potential biomarker of type II TRK inhibitor activity. As all currently available type II agents are multikinase inhibitors, rational drug design should focus on selective type II inhibitor creation. This article is highlighted in the In This Issue feature, p. 1 ., (©2020 American Association for Cancer Research.)

Although diagnosis of high-grade uterine mesenchymal tumors (UMTs) exhibiting classic morphologic features is straightforward, diagnosis is more challenging in tumors in which prototypical features are poorly developed, focal, and/or coexist with features seen in other neoplasms. Here, we sought to define the repertoire of somatic genetic alterations in diagnostically challenging UMTs with myomelanocytic differentiation, including some reported as perivascular epithelioid cell tumors (PEComas). In 17 samples from 15 women, the tumors were histologically heterogenous. Immunohistochemical expression of at least 1 melanocytic marker (HMB45, Melan-A, or MiTF) was identified in all tumors, and of myogenic markers (desmin or smooth muscle actin) in most tumors. Targeted massively parallel sequencing revealed several genetic alterations, most commonly in TP53 (41% mutation, 12% deletion), TSC2 (29% mutation, 6% deletion), RB1 (18% deletion), ATRX (24% mutation), MED12 (12% mutation), BRCA2 (12% deletion), CDKN2A (6% deletion) as well as FGFR3, NTRK1, and ERBB3 amplification (each 6%). Gene rearrangements (JAZF1-SUZ12; DNAJB6-PLAG1; and SFPQ-TFE3) were identified in 3 tumors. Integrating histopathologic, immunohistochemical, and genetic findings, tumors from 4 patients were consistent with malignant PEComa (1 TFE3-rearranged); 6 were classified as leiomyosarcomas; 3 showed overlapping features of PEComa and other sarcoma types (leiomyosarcoma or low-grade endometrial stromal sarcoma); and 2 were classified as sarcoma, not otherwise specified. Our findings suggest that diagnostically challenging UMTs with myomelanocytic differentiation represent a heterogenous group of neoplasms which harbor a diverse repertoire of somatic genetic alterations; these genetic alterations can aid classification.

Background: Data on drug-induced liver injury (DILI) and acute liver failure (ALF) in modern phase 1 oncology trials are limited, specifically with respect to the incidence and resolution of DILI and the safety of drug rechallenge., Methods: This study reviewed all patients who were recruited to phase 1 oncology trials between 2013 and 2017 at Memorial Sloan Kettering Cancer Center. Clinicopathologic data were extracted to characterize DILI, and attribution was assessed on the basis of data prospectively generated during the studies. Logistic regression models were used to explore factors related to DILI and DILI recurrence after drug rechallenge., Results: Among 1670 cases recruited to 85 phase 1 trials, 81 (4.9%) developed DILI. The rate of DILI occurrence was similar for patients in immune-based trials and patients in targeted therapy trials (5.0% vs 4.9%), as was the median time to DILI (5.5 vs 6.5 weeks; P = .48). Two patients (0.12%) met the criteria of Hy's law, although none developed ALF. The DILI resolved in 96% of the patients. Pretreatment factors were not predictive for DILI development. Thirty-six of the 81 patients underwent a drug rechallenge, and 28% of these patients developed DILI recurrence. Peak alanine aminotransferase during the initial DILI was associated with DILI recurrence (odds ratio, 1.04; 95% confidence interval, 1.0-1.09; P = .035)., Conclusions: In modern phase 1 oncology trials, DILI is uncommon, may occur at any time, and often resolves with supportive measures. Rechallenging after DILI is feasible; however, the high rate of DILI recurrence suggests that clinicians should consider the severity of the DILI episode and treatment alternatives., (© 2020 American Cancer Society.)

Randomized controlled basket trials investigating drugs targeting a rare molecular alteration are challenging. Using patients as their own control overcomes some of these challenges. Growth modulation index (GMI) is the ratio of progression-free survival (PFS) on the current therapy to time to progression (TTP) on the last prior line of therapy; GMI ≥ 1.33 is considered a threshold of meaningful clinical activity. In a retrospective, exploratory analysis among patients with advanced tropomyosin receptor kinase (TRK) fusion cancer treated with the selective TRK inhibitor larotrectinib who received ≥1 prior line of therapy for locally advanced/metastatic disease, we determined the proportion of patients with GMI ≥ 1.33; patients who had not progressed by data cut-off were censored for PFS. Among 72 eligible patients, median GMI was 2.68 (range 0.01-48.75). Forty-seven patients (65%) had GMI ≥ 1.33; 13/25 patients (52%) with GMI < 1.33 had not yet progressed on larotrectinib. Kaplan-Meier estimates showed a median GMI of 6.46. The probability of attaining GMI ≥ 1.33 was 0.75 (95% confidence interval (CI), 0.65-0.85). Median TTP on previous treatment was 3.0 months (95% CI, 2.6-4.4). Median PFS on larotrectinib was not estimable ((NE); 95% CI, NE; hazard ratio, 0.220 (95% CI, 0.146-0.332)). This analysis suggests larotrectinib improves PFS for patients with TRK fusion cancer compared with prior therapy.

Acquired mutations are pervasive across normal tissues. However, understanding of the processes that drive transformation of certain clones to cancer is limited. Here we study this phenomenon in the context of clonal hematopoiesis (CH) and the development of therapy-related myeloid neoplasms (tMNs). We find that mutations are selected differentially based on exposures. Mutations in ASXL1 are enriched in current or former smokers, whereas cancer therapy with radiation, platinum and topoisomerase II inhibitors preferentially selects for mutations in DNA damage response genes (TP53, PPM1D, CHEK2). Sequential sampling provides definitive evidence that DNA damage response clones outcompete other clones when exposed to certain therapies. Among cases in which CH was previously detected, the CH mutation was present at tMN diagnosis. We identify the molecular characteristics of CH that increase risk of tMN. The increasing implementation of clinical sequencing at diagnosis provides an opportunity to identify patients at risk of tMN for prevention strategies.

Objective: Somatic HER2 mutations occur in ~5% of cervical cancers and are considered oncogenic and associated with poor prognosis. Neratinib, an irreversible pan-HER tyrosine kinase inhibitor, is active in multiple HER2-mutant cancers. SUMMIT is a phase II basket trial investigating the efficacy and safety of neratinib in solid tumors., Methods: Patients with HER2-mutant, persistent, metastatic/recurrent cervical cancer with disease progression after platinum-based treatment for advanced/recurrent disease received oral neratinib 240 mg/day with mandatory loperamide prophylaxis during cycle 1. The primary endpoint was confirmed objective response rate (ORR). Secondary endpoints included: response duration (DOR); clinical benefit rate (CBR); progression-free survival (PFS); overall survival (OS); safety., Results: Sixteen eligible patients were enrolled; 10 (62.5%) had endocervical adenocarcinoma. The most common HER2 mutation was S310F (63% of patients). Three of 12 RECIST-measurable patients had confirmed partial responses (ORR 25%; 95%CI 5.5-57.2%); 3 had stable disease ≥16 weeks (CBR 50%; 95%CI 21.1-78.9%). DOR for responders were 5.6, 5.9, and 12.3 months. Median PFS was 7.0 months (95%CI 0.7-18.3 months); median OS was 16.8 months (95%CI 4.1-NE months). Diarrhea (75%), nausea (44%), and decreased appetite (38%) were the most common adverse events. One patient (6%) reported grade 3 diarrhea. There were no grade 4 events, and no diarrhea-related treatment discontinuations., Conclusions: Neratinib monotherapy showed evidence of activity in heavily pretreated patients with HER2-mutant cervical cancer, with no new safety signals. Given the few effective options for cervical cancer after platinum-based therapy failure, neratinib warrants further investigation in this molecularly defined patient population., Trial Registration Number: NCT01953926 (ClinicalTrials.gov), 2013-002872-42 (EudraCT)., Competing Interests: Declaration of Competing Interest A. Oaknin: has received advisory board honoraria from Roche, AstraZeneca, PharmaMar, Clovis Oncology, Tesaro, Inmunogen, Genmab, and Deciphera and travel/accommodation support from Roche, AstraZeneca, and PharmaMar. C.F. Friedman: has received institutional research funding from Bristol-Myers Squibb, Merck, and Genentech, advisory board honoraria from AstraZeneca, and serves on steering committees for the Genentech MyPathway and the Merck LYNK-002 studies (compensation waived). L.D. Roman: has received advisory board honoraria from Tempus Labs and is a consultant for Quantgene. A. D'Souza: has no competing interests. I. Brana: has received institutional research funding from Puma Biotechnology Inc. F. Clement-Bidard: has received advisory board honoraria from Pfizer, Novartis, Eli Lilly, Amgen, and AstraZeneca. J. Goldman: has received institutional research funding from Puma Biotechnology Inc. E. A. Alvarez: has received advisory board honoraria from Eisai Co. Inc. and ArQule Inc. and has been a medical consultant for Tracon Pharmaceuticals, Inc. V. Boni: has received advisory board honoraria from Loxo Oncology and Ideaya. A.C. ElNaggar: has received institutional research funding from Caris Life Sciences and advisory board honoraria from AstraZeneca, Clovis Oncology, Leap Therapeutics, Tesaro/GSK, and AbbVie Pharmaceuticals. R. Passalacqua: has received advisory board/speaker honoraria from Amgen, Astellas, Bayer, BMS, Ipsen, Janssen, Novartis, Sanofi-Aventis, Roche, MSD, and Pierre-Fabre. K.T.M. Do: has received advisory board honoraria from QED Therapeutics. A.D. Santin: has received advisory board honoraria from Merck and Tesaro and has received institutional research funding from Puma Biotechnology Inc., Immunomedics, Tesaro, Boehringer Ingelheim, and Genentech. K. Keyvanjah: is an employee and shareholder of Puma Biotechnology Inc. F. Xu: is an employee and shareholder of Puma Biotechnology Inc. L.D. Eli: is an employee and shareholder of Puma Biotechnology Inc. A.S. Lalani: is an employee and shareholder of Puma Biotechnology Inc. R.P. Bryce: is an employee and shareholder of Puma Biotechnology Inc. D.M. Hyman: has acted in a consulting/advisory role for Atara Biotherapeutics, Chugai Pharma, CytomX Therapeutics, Boehringer Ingelheim, AstraZeneca, Pfizer, Bayer, and Genentech, and has received institutional research funding from Loxo Oncology, Puma Biotechnology Inc., and AstraZeneca. He is currently employed by Loxo Oncology/Eli Lilly. F. Meric-Bernstam: has received institutional research funding from Novartis, AstraZeneca, Calithera, Aileron, Bayer, Jounce, CytoMx, eFFECTOR, Zymeworks, Puma Biotechnology Inc., Curis, Millennium, Daiichi Sankyo, AbbVie, Guardant Health, Takeda, and GlaxoSmithKline, grants/travel-related fees from Taiho, Genentech, Debiopharm Group, and Pfizer, consultancy fees from Pieris, Dialectica, Sumitomo Dainippon, Samsung Bioepis, Aduro, OrigiMed, Xencor, Jackson Laboratory, Zymeworks, and Parexel International, advisory board fees from Inflection Biosciences, GRAIL, Darwin Health, Clearlight Diagnostics, Spectrum, Mersana, and Seattle Genetics. D.H. Solit: has acted in a consulting/advisory role for Loxo Oncology, Pfizer, Illumina, Vivideon Therapeutics, QED Therapeutics, and Lilly Oncology. B.J. Monk: has received consultancy fees from Puma Biotechnology Inc., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: The tropomyosin receptor kinase (TRK) pathway controls appetite, balance, and pain sensitivity. While these functions are reflected in the on-target adverse events (AEs) observed with TRK inhibition, these AEs remain under-recognized, and pain upon drug withdrawal has not previously been reported. As TRK inhibitors are approved by multiple regulatory agencies for TRK or ROS1 fusion-positive cancers, characterizing these AEs and corresponding management strategies is crucial., Patients and Methods: Patients with advanced or unresectable solid tumors treated with a TRK inhibitor were retrospectively identified in a search of clinical databases. Among these patients, the frequency, severity, duration, and management outcomes of AEs including weight gain, dizziness or ataxia, and withdrawal pain were characterized., Results: Ninety-six patients with 15 unique cancer histologies treated with a TRK inhibitor were identified. Weight gain was observed in 53% [95% confidence interval (CI), 43%-62%] of patients and increased with time on TRK inhibition. Pharmacologic intervention, most commonly with glucagon-like peptide 1 analogs or metformin, appeared to result in stabilization or loss of weight. Dizziness, with or without ataxia, was observed in 41% (95% CI, 31%-51%) of patients with a median time to onset of 2 weeks (range, 3 days to 16 months). TRK inhibitor dose reduction was the most effective intervention for dizziness. Pain upon temporary or permanent TRK inhibitor discontinuation was observed in 35% (95% CI, 24%-46%) of patients; this was more common with longer TRK inhibitor use. TRK inhibitor reinitiation was the most effective intervention for withdrawal pain., Conclusions: TRK inhibition-related AEs including weight gain, dizziness, and withdrawal pain occur in a substantial proportion of patients receiving TRK inhibitors. This safety profile is unique relative to other anticancer therapies and warrants careful monitoring. These on-target toxicities are manageable with pharmacologic intervention and dose modification., Competing Interests: Disclosure JF has received honoraria from Genentech. AL has received research funding from Bristol Myers Squibb and NantOmics and holds equity in Sanofi. MO has served on advisory boards for PharmaMar, Novartis, and Targeted Oncology, and received travel expenses from Bristol Myers Squibb and Merck. YRM-G has received travel expenses from AstraZeneca. BTL holds two institutional patents (US62/685,057, US62/514,661), and has served on advisory boards for Genentech (subsidiary of Roche), Eli Lilly, Guardant Health, Hengrui Therapeutics, Mersana Therapeutics, and Thermo Fisher Scientific, received travel expenses from MORE Health and Resolution Bioscience, and received research funding from Amgen, AstraZeneca, BioMedValley Discoveries, Daiichi Sankyo, Genentech, GRAIL, Guardant Health, Eli Lilly, Hengrui Therapeutics, Illumina, and MORE Health. JJH has received consulting fees from Bristol Myers Squibb, Cytomx, Eli Lilly, Eisai, Exelixis, Imvax, QED, and research funding from Bristol Myers Squibb. GI has received research funding from Janssen, Mirati Therapeutics, and Novartis, and consulting fees from Mirati Therapeutics. MMG has received honoraria from Bayer and Flatiron Health, served on advisory boards for Bayer, Boehringer Ingelheim, Epizyme, Daiichi Sankyo, Karyopharm, and Springworks Therapeutics, served on a speakers’ bureau for Amgen, and received travel expenses from Epizyme. AS has received research funding from Eli Lilly, Kura Oncology, Merus, Northern Biologics, and Surface Oncology. DMH owns stock in Fount Therapeutics, has served on advisory boards for ArQule, AstraZeneca, Bayer, Boehringer Ingelheim, Chugai Pharma, CytomX, Debiopharm, Fount Therapeutics, Genentech, Eli Lilly, Janssen, Jazz Pharma, Pfizer, and Puma Biotechnology, received research funding from AstraZeneca, Bayer, Loxo Oncology, and Puma Biotechnology, and received travel expenses from Chugai Pharma and Genentech; he is currently employed by and holds equity in Loxo Oncology, a subsidiary of Eli Lilly. AD has received honoraria and/or served on advisory boards for 14ner/Elevation Oncology, Abbvie, ArcherDX, AstraZeneca, Axis Pharma, Bayer, Beigene, BergenBio, Blueprint Medicines, Exelixis, Helsinn, Hengrui Therapeutics, Loxo Oncology (subsidiary of Eli Lilly), Monopteros, MORE Health, Remedica, Roche (subsidiaries Genentech and Ignyta), Pfizer, Takeda (subsidiaries Ariad and Millennium), TP Therapeutics, Tyra Biosciences, and Verastem; and received research funding from Exelixis, Foundation Medicine GlaxoSmithKline, Pfizer, PharmaMar, Teva, and Taiho. All research funding was provided to the institution. All other authors report no financial relationships., (Copyright © 2020 European Society for Medical Oncology. Published by Elsevier Ltd. All rights reserved.)

The molecular characterization of tumors now informs clinical cancer care for many patients. This advent of molecular oncology has been driven by the expanding number of therapeutic biomarkers that can predict sensitivity to both approved agents and investigational agents. Beyond its role in driving clinical-trial enrollments and guiding therapy in individual patients, large-scale clinical genomics in oncology also represents a rapidly expanding research resource for translational scientific discovery. Here we review the progress, opportunities, and challenges of scientific and translational discovery from prospective clinical genomic screening programs now routinely conducted for patients with cancer., (© 2020. Springer Nature America, Inc.)

Purpose: The activating mutation AKT1 E17K occurs in approximately 7% of estrogen receptor-positive (ER + ) metastatic breast cancer (MBC). We report, from a multipart, first-in-human, phase I study (NCT01226316), tolerability and activity of capivasertib, an oral AKT inhibitor, as monotherapy or combined with fulvestrant in expansion cohorts of patients with AKT1 E17K -mutant ER + MBC., Patients and Methods: Patients with an AKT1 E17K mutation, detected by local (next-generation sequencing) or central (plasma-based BEAMing) testing, received capivasertib 480 mg twice daily, 4 days on, 3 days off, weekly or 400 mg twice daily combined with fulvestrant at the labeled dose. Study endpoints included safety, objective response rate (ORR; RECIST v1.1), progression-free survival (PFS), and clinical benefit rate at 24 weeks (CBR 24 ). Biomarker analyses were conducted in the combination cohort., Results: From October 2013 to August 2018, 63 heavily pretreated patients received capivasertib (20 monotherapy, 43 combination). ORR was 20% with monotherapy, and within the combination cohort was 36% in fulvestrant-pretreated and 20% in fulvestrant-naïve patients, although the latter group may have had more aggressive disease at baseline. AKT1 E17K mutations were detectable in plasma by BEAMing (95%, 41/43), droplet digital PCR (80%, 33/41), and next-generation sequencing (76%, 31/41). A ≥50% decrease in AKT1 E17K at cycle 2 day 1 was associated with improved PFS. Combination therapy appeared more tolerable than monotherapy [most frequent grade ≥3 adverse events: rash (9% vs. 20%), hyperglycemia (5% vs. 30%), diarrhea (5% vs. 10%)]., Conclusions: Capivasertib demonstrated clinically meaningful activity in heavily pretreated patients with AKT1 E17K -mutant ER + MBC, including those with prior disease progression on fulvestrant. Tolerability and activity appeared improved by the combination., (©2020 American Association for Cancer Research.)

Background: Kinase fusions are rare and poorly characterized in breast cancer (BC). We aimed to characterize kinase fusions within a large cohort of advanced BC., Patients and Methods: A total of 4854 patients with BC were analyzed by Memorial Sloan Kettering-Integrated Mutation Profiling of Actionable Cancer Targets (MSK-IMPACT) targeted DNAseq and MSK-Fusion targeted RNAseq during the study time period., Results: Twenty-seven of 4854 (0.6%) patients harbored fusions: 11 FGFR (five FGFR2, three FGFR3, three FGFR1), five BRAF, four NTRK1, two RET, two ROS1, one ALK, one ERBB2, and one MET. A history of endocrine therapy was present in 15 (56%) of fusion-positive BC; eight of the 15 cases had available pre-treatment samples, of which six were fusion-negative. None of the fusion-positive BC samples harbored ESR1 hotspot mutations. Two patients with acquired LMNA-NTRK1 fusions and metastatic disease received larotrectinib and demonstrated clinical benefit., Conclusion: Kinase fusions in BC are extremely rare, and appear to be enriched in hormone-resistant, metastatic carcinomas and mutually exclusive with ESR1 mutations. The present study expands the spectrum of genetic alterations activating mitogen-activated protein kinase (MAPK) signaling that can substitute for ESR1 mutations in this setting. Molecular testing at progression after endocrine therapy should include fusion testing, particularly in the absence of ESR1 hotspot alterations, in an effort to identify additional therapeutic options which may provide substantial clinical benefit., Competing Interests: Disclosure PR has received honoraria for consulting/advisory board for Novartis, AstraZeneca, Foundation Medicine and institutional research support from GRAIL, Inc. MS has received research funds from Puma Biotechnology, AstraZeneca, Daiichi Sankyo, Immunomedics, Targimmune, and Menarini Ricerche. He is in the scientific advisory board (SAB) of Menarini Ricerche and Bioscience Institute and is a cofounder of Medendi.org. ML has received honoraria for ad hoc advisory board participation from Merck, Astra-Zeneca, Bristol Myers Squibb, Takeda, Lilly Oncology and Bayer, and research support from LOXO Oncology, Merus, and Helsinn Therapeutics. DMH has received personal fees from Chugai Pharma, Boehringer Ingelheim, AstraZeneca, Pfizer, Bayer, Debiopharm Group, and Genentech/Roche, as well as grants from Bayer, AstraZeneca, Puma Biotechnology, and Loxo Oncology, and employment and equity in Eli Lilly. All personal fees and grants are for work outside the submitted work. AD has honoraria from Medscape, OncLive, PeerVoice, Physician Education Resources, Tyra Biosciences, Targeted Oncology, MORE Health, Research to Practice, Foundation Medicine, PeerView, AstraZeneca, Ignyta/Genentech/Roche, Bayer; consulting roles at Ignyta, Loxo/Lilly, TP Therapeutics, AstraZeneca, Pfizer, Blueprint Medicines, Genentech/Roche, Takeda, Helsinn Therapeutics, BeiGene, Hengrui Therapeutics, Exelixis, 14ner/Elevation Oncology, GlaxoSmithKline, Exelixis, Teva, Taiho, Merck, Puma, Merus, Boeringer Ingelheim, PharmaMar, and Bayer. RB has received a grant from Archer, honoraria for advisory board participation from Loxo oncology and speaking fees from Illumina. SC has received honoraria for ad hoc consulting for Eli Lilly, Sermonix, BMS, Paige AI, Context Therapeutics, Revolution Medicine, and Novartis; research support to the institution from Daiichi Sankyo, Novartis, Eli Lilly, Genentech, and Sanofi. JFH has received honoraria from Medscape, Cor2Ed, ClearView Healthcare Partners, Illumina, and Axiom Healthcare Strategies, as well as research funding from Bayer, Eli Lilly, and Boehringer Ingelheim. All remaining authors have declared no conflicts of interest., (Copyright © 2020 European Society for Medical Oncology. Published by Elsevier Ltd. All rights reserved.)

Background Human epidermal growth factor receptor 2 (HER2)-targeted therapies are successful in patients with HER2-positive malignancies; however, spatial and temporal heterogeneity of HER2 expression may prevent identification of optimal patients for these therapies. Purpose To determine whether imaging with the HER2-targeted PET tracer zirconium 89 ( 89 Zr)-pertuzumab can depict HER2-positive metastases in women with HER2-negative primary breast cancer. Materials and Methods From January to June 2019, women with biopsy-proven HER2-negative primary breast cancer and biopsy-proven metastatic disease were enrolled in a prospective clinical trial ( ClinicalTrials.gov NCT02286843) and underwent 89 Zr-pertuzumab PET/CT for noninvasive whole-biopsy evaluation of potential HER2-positive metastases. 89 Zr-pertuzumab-avid foci that were suspicious for HER2-positive metastases were tissue sampled and examined by pathologic analysis to document HER2 status. Results Twenty-four women (mean age, 55 years ± 11 [standard deviation]) with HER2-negative primary breast cancer were enrolled. Six women demonstrated foci at 89 Zr-pertuzumab PET/CT that were suspicious for HER2-positive disease. Of these six women, three had biopsy-proven HER2-positive metastases, two had pathologic findings that demonstrated HER2-negative disease, and one had a fine-needle aspirate with inconclusive results. Conclusion Human epidermal growth factor receptor 2 (HER2)-targeted imaging with zirconium 89-pertuzumab PET/CT was successful in detecting HER2-positive metastases in women with HER2-negative primary breast cancer. This demonstrates the ability of targeted imaging to identify patients for targeted therapies that might not otherwise be considered. © RSNA, 2020 Online supplemental material is available for this article. See the editorial by Mankoff and Pantel in this issue.

Purpose: We examined whether prospective molecular characterization of advanced metastatic disease can reveal grade and/or histology-specific differences to inform diagnosis and facilitate enrollment onto clinical trials., Experimental Design: Patients with uterine sarcoma consented to a prospective study of next-generation sequencing (NGS). Clinical annotations were extracted from their medical record. Tumor and matched normal DNA were subjected to NGS, and the genomic landscape was explored for survival correlations and therapeutic targetability., Results: Tumors from 107 women were sequenced and included leiomyosarcoma ( n = 80), high-grade non-leiomyosarcoma ( n = 22), low-grade endometrial stromal sarcoma (LG-ESS, n = 4), and smooth muscle tumor of uncertain malignant potential (STUMP, n = 2). Genomic profiling influenced histologic diagnosis in three cases. Common uterine leiomyosarcoma alterations were loss-of-function mutations in TP53 (56%), RB1 (51%), and ATRX (31%). Homozygous deletions of BRCA2 were present in 5% of these patients. PTEN alteration frequency was higher in the metastases samples as compared with the primary samples. Genomes of low-grade tumors were largely silent, while 50.5% of high-grade tumors had whole-genome duplication. Two metastatic uterine leiomyosarcoma cases were hypermutated. Both had prolonged disease-free survival. Potentially actionable mutations were identified in 48 patients (45%), 8 (17%) of whom received matched therapy with 2 achieving clinical responses. Among patients with uterine leiomyosarcoma with somatic BRCA2 alterations, sustained partial responses were observed with PARP inhibitor-containing therapy., Discussion: Prospective genomic profiling can contribute to diagnostic precision and inform treatment selection in patients with uterine sarcomas. There was evidence of clinical benefit in patients with uterine leiomyosarcoma with somatic BRCA2 alterations treated with PARP inhibitors., (©2020 American Association for Cancer Research.)

Background: Erdheim-Chester disease (ECD) is a rare histiocytic neoplasm characterized by recurrent alterations in the MAPK (mitogen-activating protein kinase) pathway. The existing literature about the neuro-oncological spectrum of ECD is limited., Methods: We present retrospective clinical, radiographic, pathologic, molecular, and treatment data from 30 patients with ECD neurohistiocytic involvement treated at a tertiary center., Results: Median age was 52 years (range, 7-77), and 20 (67%) patients were male. Presenting symptoms included ataxia in 19 patients (63%), dysarthria in 14 (47%), diabetes insipidus in 12 (40%), cognitive impairment in 10 (33%), and bulbar affect in 9 (30%). Neurosurgical biopsy specimens in 8 patients demonstrated varied morphologic findings often uncharacteristic of typical ECD lesions. Molecular analysis revealed mutations in BRAF (18 patients), MAP2K1 (5), RAS isoforms (2), and 2 fusions involving BRAF and ALK. Conventional therapies (corticosteroids, immunosuppressants, interferon-alpha [IFN-α], cytotoxic chemotherapy) led to partial radiographic response in 8/40 patients (20%) by MRI with no complete responses, partial metabolic response in 4/16 (25%), and complete metabolic response in 1/16 (6%) by 18F-fluorodeoxyglucose (FDG)-PET scan. In comparison, targeted (kinase inhibitor) therapies yielded partial radiographic response in 10/27 (37%) and complete radiographic response in 14/27 (52%) by MRI, and partial metabolic response in 6/25 (24%) and complete metabolic response in 17/25 (68%) by FDG-PET scan., Conclusions: These data highlight underrecognized symptomatology, heterogeneous neuropathology, and robust responses to targeted therapies across the mutational spectrum in ECD patients with neurological involvement, particularly when conventional therapies have failed., (© The Author(s) 2020. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

BRAF V600 mutations occur in a wide range of tumor types, and RAF inhibition has become standard in several of these cancers. Despite this progress, BRAF V600 mutations have historically been considered a clear demonstration of tumor lineage context-dependent oncogene addiction, based predominantly on the insensitivity to RAF inhibition in colorectal cancer. However, the true broader activity of RAF inhibition pan-cancer remains incompletely understood. To address this, we conducted a multicohort "basket" study of the BRAF inhibitor vemurafenib in non-melanoma BRAF V600 mutation-positive solid tumors. In total, 172 patients with 26 unique cancer types were treated, achieving an overall response rate of 33% and median duration of response of 13 months. Responses were observed in 13 unique cancer types, including historically treatment-refractory tumor types such as cholangiocarcinoma, sarcoma, glioma, neuroendocrine carcinoma, and salivary gland carcinomas. Collectively, these data demonstrate that single-agent BRAF inhibition has broader clinical activity than previously recognized. SIGNIFICANCE: These data suggest that BRAF V600 mutations lead to oncogene addiction and are clinically actionable in a broad range of non-melanoma cancers, including tumor types in which RAF inhibition is not currently considered standard of care. See related commentary by Ribas and Lo, p. 640 . This article is highlighted in the In This Issue feature, p. 627 ., (©2020 American Association for Cancer Research.)

Amplification of and oncogenic mutations in ERBB2 , the gene encoding the HER2 receptor tyrosine kinase, promote receptor hyperactivation and tumor growth. Here we demonstrate that HER2 ubiquitination and internalization, rather than its overexpression, are key mechanisms underlying endocytosis and consequent efficacy of the anti-HER2 antibody-drug conjugates (ADC) ado-trastuzumab emtansine (T-DM1) and trastuzumab deruxtecan (T-DXd) in lung cancer cell lines and patient-derived xenograft models. These data translated into a 51% response rate in a clinical trial of T-DM1 in 49 patients with ERBB2 -amplified or -mutant lung cancers. We show that cotreatment with irreversible pan-HER inhibitors enhances receptor ubiquitination and consequent ADC internalization and efficacy. We also demonstrate that ADC switching to T-DXd, which harbors a different cytotoxic payload, achieves durable responses in a patient with lung cancer and corresponding xenograft model developing resistance to T-DM1. Our findings may help guide future clinical trials and expand the field of ADC as cancer therapy. SIGNIFICANCE: T-DM1 is clinically effective in lung cancers with amplification of or mutations in ERBB2 . This activity is enhanced by cotreatment with irreversible pan-HER inhibitors, or ADC switching to T-DXd. These results may help address unmet needs of patients with HER2-activated tumors and no approved targeted therapy. See related commentary by Rolfo and Russo, p. 643 . This article is highlighted in the In This Issue feature, p. 627 ., (©2020 American Association for Cancer Research.)

Prospective molecular characterization of cancer has enabled physicians to define the genomic changes of each patient's tumor in real time and select personalized therapies based on these detailed portraits. Despite the promise of such an approach, previously unrecognized biological and therapeutic complexity is emerging. Here, we synthesize lessons learned and discuss the steps required to extend the benefits of genome-driven oncology, including proposing strategies for improved drug design, more nuanced patient selection, and optimized use of available therapies. Finally, we suggest ways that next-generation genome-driven clinical trials can evolve to accelerate our understanding of cancer biology and improve patient outcomes., Competing Interests: Declaration of Interests Y.R.M.-G. acknowledges receipt of support for travel, accommodation, and expenses from AstraZeneca and has received training through a K30 grant (CTSA UL1TR00457). B.S.T. reports receiving honoraria and research funding from Genentech and Illumina and advisory board activities for Boehringer Ingelheim and Loxo Oncology, a wholly owned subsidiary of Eli Lilly. D.M.H. reports paid consulting work for Chugai, Boehringer Ingelheim, AstraZeneca, Pfizer, Bayer, Genentech/Roche, and Fount Therapeutics, and research grants from AstraZeneca, Puma Biotechnology, Loxo Oncology, and Bayer. D.M.H. is currently employed by Loxo, a wholly owned subsidiary of Eli Lilly. A.M.S. has no financial interests to disclose., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background: The selective TRK inhibitor larotrectinib was approved for paediatric and adult patients with advanced TRK fusion-positive solid tumours based on a primary analysis set of 55 patients. The aim of our analysis was to explore the efficacy and long-term safety of larotrectinib in a larger population of patients with TRK fusion-positive solid tumours., Methods: Patients were enrolled and treated in a phase 1 adult, a phase 1/2 paediatric, or a phase 2 adolescent and adult trial. Some eligibility criteria differed between these studies. For this pooled analysis, eligible patients were aged 1 month or older, with a locally advanced or metastatic non-CNS primary, TRK fusion-positive solid tumour, who had received standard therapy previously if available. This analysis set includes the 55 patients on which approval of larotrectinib was based. Larotrectinib was administered orally (capsule or liquid formulation), on a continuous 28-day schedule, to adults mostly at a dose of 100 mg twice daily, and to paediatric patients mostly at a dose of 100 mg/m 2 (maximum of 100 mg) twice daily. The primary endpoint was objective response as assessed by local investigators in an intention-to-treat analysis. Contributing trials are registered with ClinicalTrials.gov, NCT02122913 (active not recruiting), NCT02637687 (recruiting), and NCT02576431 (recruiting)., Findings: Between May 1, 2014, and Feb 19, 2019, 159 patients with TRK fusion-positive cancer were enrolled and treated with larotrectinib. Ages ranged from less than 1 month to 84 years. The proportion of patients with an objective response according to investigator assessment was 121 (79%, 95% CI 72-85) of 153 evaluable patients, with 24 (16%) having complete responses. In a safety population of 260 patients treated regardless of TRK fusion status, the most common grade 3 or 4 larotrectinib-related adverse events were increased alanine aminotransferase (eight [3%] of 260 patients), anaemia (six, 2%), and decreased neutrophil count (five [2%]). The most common larotrectinib-related serious adverse events were increased alanine aminotransferase (two [<1%] of 260 patients), increased aspartate aminotransferase (two [<1%]), and nausea (two [<1%]). No treatment-related deaths occurred., Interpretation: These data confirm that TRK fusions define a unique molecular subgroup of advanced solid tumours for which larotrectinib is highly active. Safety data indicate that long-term administration of larotrectinib is feasible., Funding: Bayer and Loxo Oncology., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Purpose: TRK inhibitors achieve marked tumor-agnostic efficacy in TRK fusion-positive cancers and consequently are now an established standard of care. Little is known, however, about the demographics, outcomes, response to alternative standard therapies, or genomic characteristics of TRK fusion-positive cancers., Experimental Design: Utilizing a center-wide screening program involving more than 26,000 prospectively sequenced patients, genomic and clinical data from all cases with TRK fusions were extracted. An integrated analysis was performed of genomic, therapeutic, and phenomic outcomes., Results: We identified 76 cases with confirmed TRK fusions (0.28% overall prevalence) involving 48 unique rearrangements and 17 cancer types. The presence of a TRK fusion was associated with depletion of concurrent oncogenic drivers ( P < 0.001) and lower tumor mutation burden ( P < 0.001), with the exception of colorectal cancer where TRK fusions cooccur with microsatellite instability (MSI-H). Longitudinal profiling in a subset of patients indicated that TRK fusions were present in all sampled timepoints in 82% (14/17) of cases. Progression-free survival on first-line therapy, excluding TRK inhibitors, administered for advanced disease was 9.6 months [95% confidence interval (CI), 4.8-13.2]. The best overall response rate achieved with chemotherapy containing-regimens across all lines of therapy was 63% (95% CI, 41-81). Among 12 patients treated with checkpoint inhibitors, a patient with MSI-H colorectal cancer had the only observed response., Conclusions: TRK fusion-positive cancers can respond to alternative standards of care, although efficacy of immunotherapy in the absence of other predictive biomarkers (MSI-H) appears limited. TRK fusions are present in tumors with simple genomes lacking in concurrent drivers that may partially explain the tumor-agnostic efficacy of TRK inhibitors., (©2019 American Association for Cancer Research.)

AKT inhibitors have promising activity in AKT1 E17K -mutant estrogen receptor (ER)-positive metastatic breast cancer, but the natural history of this rare genomic subtype remains unknown. Utilizing AACR Project GENIE, an international clinicogenomic data-sharing consortium, we conducted a comparative analysis of clinical outcomes of patients with matched AKT1 E17K -mutant ( n = 153) and AKT1 -wild-type ( n = 302) metastatic breast cancer. AKT1 -mutant cases had similar adjusted overall survival (OS) compared with AKT1 -wild-type controls (median OS, 24.1 vs. 29.9, respectively; P = 0.98). AKT1 -mutant cases enjoyed longer durations on mTOR inhibitor therapy, an observation previously unrecognized in pivotal clinical trials due to the rarity of this alteration. Other baseline clinicopathologic features, as well as durations on other classes of therapy, were broadly similar. In summary, we demonstrate the feasibility of using a novel and publicly accessible clincogenomic registry to define outcomes in a rare genomically defined cancer subtype, an approach with broad applicability to precision oncology. SIGNIFICANCE: We delineate the natural history of a rare genomically distinct cancer, AKT1 E17K -mutant ER-positive breast cancer, using a publicly accessible registry of real-world patient data, thereby illustrating the potential to inform drug registration through synthetic control data. See related commentary by Castellanos and Baxi, p. 490 ., (©2020 American Association for Cancer Research.)

The identification of molecular targets and the growing knowledge of their cellular functions have led to the development of small molecule inhibitors as a major therapeutic class for cancer treatment. Both multitargeted and highly selective kinase inhibitors are used for the treatment of advanced treatment-resistant cancers, and many have also achieved regulatory approval for early clinical settings as adjuvant therapies or as first-line options for recurrent or metastatic disease. Lessons learned from the development of these agents can accelerate the development of next-generation inhibitors to optimise the therapeutic index, overcome drug resistance, and establish combination therapies. The future of small molecule inhibitors is promising as there is the potential to investigate novel difficult-to-drug targets, to apply predictive non-clinical models to select promising drug candidates for human evaluation, and to use dynamic clinical trial interventions with liquid biopsies to deliver precision medicine., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Background: PI3K pathway activation is common in endometrial cancer. We evaluated the safety and efficacy of the dual PI3K/mTOR inhibitor, LY3023414, in patients with advanced endometrial cancer harboring activating mutations in the PI3K pathway., Methods: We conducted a single-arm phase 2 study of monotherapy LY3023414. Eligible patients had advanced endometrial cancer of any grade, prior management with 1-4 cytotoxic lines, and PI3K pathway activation prospectively defined as a loss-of-function PTEN alteration or activating alteration in PIK3CA, AKT1, PIK3R1, PIK3R2, or MTOR. The primary objective was best overall response rate (ORR) per RECIST 1.1., Results: Twenty-eight patients were treated; histologies included endometroid (39%), carcinosarcoma (25%), serous (21%), and mixed (14%). Patients were heavily pretreated, with a median of 2 prior cytotoxic lines (range, 1-3). The most common alterations involved PIK3CA (68%), PTEN (43%), and PIK3R1 (32%). In the 25 efficacy-evaluable patients, the ORR was 16% (90% CI, 7%-100%), and the clinical benefit rate was 28% (90% CI, 16%-100%). Four patients had a confirmed partial response, and 2 responses lasted for >9 months. The median progression-free survival and overall survival were 2.5 months (95% CI, 1.2-3.0) and 9.2 months (95% CI, 5.0-15.9), respectively. The most common all-grade treatment-related adverse events were anemia (71%), hyperglycemia (71%), hypoalbuminemia (68%), and hypophosphatemia (61%). No correlation between molecular alterations and response was observed., Conclusion: In patients with heavily pretreated advanced endometrial cancer prospectively selected for tumors with activating PI3K pathway mutations, LY3023414 demonstrated modest single-agent activity and a manageable safety profile., (© 2019 American Cancer Society.)

HER2 mutations define a subset of metastatic breast cancers with a unique mechanism of oncogenic addiction to HER2 signaling. We explored activity of the irreversible pan-HER kinase inhibitor neratinib, alone or with fulvestrant, in 81 patients with HER2 -mutant metastatic breast cancer. Overall response rate was similar with or without estrogen receptor (ER) blockade. By comparison, progression-free survival and duration of response appeared longer in ER + patients receiving combination therapy, although the study was not designed for direct comparison. Preexistent concurrent activating HER2 or HER3 alterations were associated with poor treatment outcome. Similarly, acquisition of multiple HER2 -activating events, as well as gatekeeper alterations, were observed at disease progression in a high proportion of patients deriving clinical benefit from neratinib. Collectively, these data define HER2 mutations as a therapeutic target in breast cancer and suggest that coexistence of additional HER signaling alterations may promote both de novo and acquired resistance to neratinib. SIGNIFICANCE: HER2 mutations define a targetable breast cancer subset, although sensitivity to irreversible HER kinase inhibition appears to be modified by the presence of concurrent activating genomic events in the pathway. These findings have implications for potential future combinatorial approaches and broader therapeutic development for this genomically defined subset of breast cancer. This article is highlighted in the In This Issue feature, p. 161 ., (©2019 American Association for Cancer Research.)

An Amendment to this paper has been published and can be accessed via a link at the top of the paper.