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Background: Undetectable circulating tumor DNA (ctDNA) is an obstacle to performing comprehensive genomic profiling in daily practice to identify genomic alterations. We investigated the associations between clinicopathological factors and undetectable ctDNA using a commercially available comprehensive genomic profiling assay in metastatic prostate cancer., Patients and Methods: Patients treated with systemic treatment for metastatic prostate cancer were included. ctDNA was analyzed by FoundationOne ® Liquid CDx at enrollment. The associations between clinicopathological characteristics and ctDNA detection were analyzed., Results: The number of bone metastasis was associated with ctDNA detection (odds ratio [95% confidence interval], 13.6 [1.71-108], P = 0.014). An algorithm predicting ctDNA detection using clinicopathological parameters was created. If ≥ 4 bone metastases were observed, ctDNA detection was estimated to be 98.9%. Among the patients with < 4 bone metastases, if two or three features among ISUP grade group 5, PSA level ≥ 10 ng/ml, and castration resistance were present, the ctDNA detection rate was 96.7% while the ctDNA detection rate was 86.3% if no or only one feature was present., Conclusions: An algorithm created in this study is helpful in determining when to undertake comprehensive genomic profiling assay using blood., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Circulating tumor DNA (ctDNA) is the fraction of cell-free DNA in patient blood that originates from a tumor. Advances in DNA sequencing technologies and our understanding of the molecular biology of tumors have increased interest in exploiting ctDNA to facilitate detection of molecular residual disease (MRD). Analysis of ctDNA as a promising MRD biomarker of solid malignancies has a central role in precision medicine initiatives exemplified by our CIRCULATE-Japan project involving patients with resectable colorectal cancer. Notably, the project underscores the prognostic significance of the ctDNA status at 4 weeks post-surgery and its correlation to adjuvant therapy efficacy at interim analysis. This substantiates the hypothesis that MRD is a critical prognostic indicator of relapse in patients with colorectal cancer. Despite remarkable advancements, challenges endure, primarily attributable to the exceedingly low ctDNA concentration in peripheral blood, particularly in scenarios involving low tumor shedding and the intrinsic error rates of current sequencing technologies. These complications necessitate more sensitive and sophisticated assays to verify the clinical utility of MRD across all solid tumors. Whole genome sequencing (WGS)-based tumor-informed MRD assays have recently demonstrated the ability to detect ctDNA in the parts-per-million range. This review delineates the current landscape of MRD assays, highlighting WGS-based approaches as the forefront technique in ctDNA analysis. Additionally, it introduces our upcoming endeavor, WGS-based pan-cancer MRD detection via ctDNA, in our forthcoming project, SCRUM-Japan MONSTAR-SCREEN-3., (© 2024. The Author(s).)

Purpose: To understand the mutational landscape of circulating tumor DNA (ctDNA) and tumor tissue of patients with hormone receptor-positive (HR+), human epidermal growth factor receptor-2-negative (HER2-) metastatic breast cancer (MBC) treated with abemaciclib + endocrine therapy (ET)., Methods: Blood samples for ctDNA and/or tissue samples were collected from abemaciclib-treated patients with HR+/HER2- MBC enrolled in the SCRUM-Japan MONSTAR-SCREEN project. Blood samples were collected before abemaciclib initiation (baseline) and at disease progression/abemaciclib discontinuation (post abemaciclib treatment). Clinical and genomic characteristics including neoplastic burden (measured by shedding rate and maximum variant allele frequency [VAF]) were assessed at baseline. Genomic alterations in ctDNA were compared in paired baseline and post abemaciclib treatment samples., Results: All patients (N = 97) were female (median age, 57 years [IQR, 50-67]). In baseline ctDNA (n = 77), PIK3CA (37%), TP53 (28%), ESR1 (16%), and GATA3 (11%) were the most frequently mutated genes. Baseline tissue samples (n = 79) showed similar alteration frequencies. Among patients with baseline ctDNA data, 30% had received previous ET. ESR1 alteration frequency (35% v 8%; P < .01), median shedding rate (3 v 2), and maximum somatic VAF (4 v 0.8; both P < .05) were significantly higher in ctDNA from patients with previous ET than those without previous ET. In paired ctDNA samples (n = 33), PIK3CA and ESR1 alteration frequencies were higher after abemaciclib treatment than at baseline, though not statistically significant. Among the post-treatment alterations, those newly acquired were detected most frequently in FGF3/4/19 (18%); PIK3CA , TP53 , CCND1 , and RB1 (all 15%); and ESR1 (12%)., Conclusion: We summarized the ctDNA and cancer tissue mutational landscape, including overall neoplastic burden and PIK3CA and ESR1 hotspot mutations in abemaciclib-treated patients with HR+/HER2- MBC. The data provide insights that could help optimize treatment strategies in this population.

Background: Liquid biopsy is an alternative to tissue specimens for tumour genotyping. However, the frequency of genomic alterations with low circulating-tumour DNA (ctDNA) shedding is shown in pancreatic ductal adenocarcinoma (PDAC). We, therefore, investigated the prevalence of KRAS mutations and ctDNA fraction by the metastatic site in patients with PDAC., Methods: This study enrolled previously treated PDAC patients from a plasma genomic profiling study; ctDNA analysis was performed using Guardant360 at disease progression before initiating subsequent treatment., Results: In 512 patients with PDAC, KRAS mutations were detected in 57%. The frequency of KRAS mutation in ctDNA differed depending on the metastatic organ; among patients with single-organ metastasis (n = 296), KRAS mutation detection rate was significantly higher in patients with metastasis to the liver (78%). In addition, the median maximum variant allele frequency (VAF) was higher with metastasis to the liver (1.9%) than with metastasis to the lungs, lymph nodes, peritoneum or with locally advanced disease (0.2%, 0.4%, 0.2% and 0.3%, respectively)., Conclusion: The prevalence of KRAS mutations and maximum VAF were higher in patients with metastasis to the liver than in those with metastasis to other sites. This study indicated the clinical utility of ctDNA analysis, especially in PDAC with liver metastases., (© 2023. The Author(s), under exclusive licence to Springer Nature Limited.)

The body of evidence supporting the utility of the detection of molecular residual disease (MRD) in resected colorectal cancer (CRC) using circulating tumor DNA (ctDNA) analysis is rapidly growing. Furthermore, this evidence provides the rationale for escalation and de-escalation adjuvant chemotherapy (ACT) strategies using ctDNA MRD analysis. This has led to various randomized clinical trials, and CIRCULATE-Japan is one of the largest of these trial platforms. In this review, we provide an overview of the potential utility of ctDNA-based MRD detection for escalation and de-escalation ACT approaches. Furthermore, we highlight the feasibility using ctDNA clearance as a surrogate endpoint for ACT trials in patients with resected CRC, based on findings of the CIRCULATE-Japan project., Competing Interests: Disclosure S.S. declares no conflicts of interest. Y.N. reports honoraria from Chugai Pharmaceutical, Merck Biopharma, and Guardant Health AMEA and research grants from Taiho Pharmaceutical, Chugai Pharmaceutical, Guardant Health, Genomedia, Daiichi Sankyo, Seagen, and Roche Diagnostics outside the submitted work. E.O. reports research funding from Guardant Health and Verily Life Science, and speaker's bureau at Chugai Pharmaceutical, Eli Lilly, Merck biopharm, Bayer, Ono Pharmaceutical, Taiho Pharmaceutical, Takeda Pharmaceutical, and Bristol Myers. T.Y. reports grants from Sanofi, Daiichi Sankyo, PAREXEL, Pfizer, Amgen, Genomedia, Sysmex, Nippon Boehringer; grants and honoraria from Ono Pharmaceutical, Taiho Pharmaceutical, MSD; Chugai Pharmaceutical; and honoraria from Eli Lilly, Merck Biopharma, and Bayer Yakuhin., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Comprehensive genomic profiling is increasingly used to facilitate precision oncology based on molecular stratification. In addition to conventional tissue comprehensive genomic profiling, comprehensive genomic profiling of circulating tumor DNA has become widely utilized in cancer care owing on its advantages, including less invasiveness, rapid turnaround time, and capturing heterogeneity. However, circulating tumor DNA comprehensive genomic profiling has some limitations, mainly false negatives due to low levels of plasma circulating tumor deoxyribonucleic acid and false positives caused by clonal hematopoiesis. Nevertheless, no guidelines and recommendations fully address these issues. Here, an expert panel committee involving representatives from 12 Designated Core Hospitals for Cancer Genomic Medicine in Japan was organized to develop expert consensus recommendations for the use of circulating tumor deoxyribonucleic acid-based comprehensive genomic profiling. The aim was to generate guidelines for clinicians and allied healthcare professionals on the optimal use of the circulating tumor DNA assays in advanced solid tumors and to aid the design of future clinical trials that utilize and develop circulating tumor DNA assays to refine precision oncology. Fourteen clinical questions regarding circulating tumor deoxyribonucleic acid comprehensive genomic profiling including the timing of testing and considerations for interpreting results were established by searching and curating associated literatures, and corresponding recommendations were prepared based on the literature for each clinical question. Final consensus recommendations were developed by voting to determine the level of each recommendation by the Committee members., (© 2022 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.)

We used a real-world database (GuardantINFORM TM ) to analyze the treatment choices for patients with mCRC who underwent next-generation sequencing of circulating tumor DNA (ctDNA) using a commercially available test (Guardant360 ® ) after first- or second-line therapy. From 18,875 patients with claims for CRC, 1064 had confirmed metastatic disease and sufficient histories for analysis (median age 59 years, 44.8% female, 44.5% left-sided). ctDNA was detectable for 997/1064 (93.7%) patients. Clinically actionable molecular profiles were present for 507/1064 (47.7%) patients, including those who had not received targeted therapy in the previous line (410/926, 44.3%). Second- or third-line targeted therapies were administered to 338/1064 patients (31.8%) and were considered matched for 193/338 (57.1%) patients. Therapies administered after testing were informed by the ctDNA results in 56.7% of patients overall (603/1064). Time to treatment discontinuation was most favorable for patients with a clinically actionable ctDNA profile who received matched therapy. This analysis demonstrates the real-world clinical value of plasma-based comprehensive genomic profiling for selecting appropriate molecular-targeted therapies in mCRC patients with disease progression after first- or second-line therapy.

According to the current international guidelines, high-risk patients diagnosed with pathological T1 (pT1) colorectal cancer (CRC) who underwent complete local resection but may have risk of developing lymph node metastasis (LNM) are recommended additional intestinal resection with lymph node dissection. However, around 90% of the patients without LNM are exposed to the risk of being overtreated due to the insufficient pathological criteria for risk stratification of LNM. Circulating tumor DNA (ctDNA) is a noninvasive biomarker for molecular residual disease and relapse detection after treatments including surgical and endoscopic resection of solid tumors. The CIRCULATE-Japan project includes a large-scale patient-screening registry of the GALAXY study to track ctDNA status of patients with stage II to IV or recurrent CRC that can be completely resected. Based on the CIRCULATE-Japan platform, we launched DENEB, a new prospective study, within the GALAXY study for patients with pT1 CRC who underwent complete local resection and were scheduled for additional intestinal resection with lymph node dissection based on the standard pathologic risk stratification criteria for LNM. The aim of this study is to explore the ability of predicting LNM using ctDNA analysis compared with the standard pathological criteria. The ctDNA assay will build new evidence to establish a noninvasive personalized diagnosis in patients, which will facilitate tailored/optimal treatment strategies for CRC patients., (© 2021 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.)

Purpose: Low concordance between plasma-based and tissue-based tests for determining the RAS mutational status have been reported in some but not all patients with limited-extent metastatic colorectal cancer (mCRC). In this study, we investigated the relationship between metastatic site and circulating tumor DNA (ctDNA) detection using ctDNA genotyping, an alternative to tissue genotyping for precision oncology., Materials and Methods: We investigated the relationship between metastatic site and ctDNA detection using Guardant360, a next-generation sequencing ctDNA assay, in mCRC patients with single-organ metastasis in the SCRUM-Japan GOZILA study (UMIN000029315)., Results: Of 1,187 patients with mCRC enrolled in GOZILA, 138 were eligible (49 with liver-only, 15 with lymph node-only, 27 with peritoneum-only, and 47 with lung-only metastases). The concordance of RAS / BRAF status between Guaradant360 and tissue in vitro diagnostic tests was 95.9% in patients with liver-only, 80.0% in lymph node-only, 56.0% in peritoneum-only, and 65.9% in lung-only metastases. ctDNA fraction, as measured by the median maximum variant allelic fraction (max VAF), and median number of detected variants were 23.1% and five in liver-only, 6.0% and five in lymph node-only, 0.4% and three in peritoneum-only, and 0.4% and three in lung-only metastases, respectively (all P < .001, Kruskal-Wallis test). Few patients with liver-only (2.0%) and lymph node-only metastasis (13.3%) had a max VAF < 0.2%, which is required to ensure a detection limit of 95%, but max VAF was more frequently < 0.2% in patients with lung-only (27.7%) or peritoneum-only metastasis (29.6%)., Conclusion: Patients with lung-only and peritoneum-only metastatic disease have significantly lower levels of ctDNA, suggesting decreased clinical sensitivity for subclonal variants. This observation suggests that such patients may benefit from concurrent tissue and plasma testing to provide optimal genotyping for subsequent therapy selection., Competing Interests: Hideaki BandoHonoraria: Taiho Pharmaceutical, Takeda, Chugai Pharma, Sanofi, Yakult Honsha, Merck Serono, Lilly Japan, Ono Pharmaceutical, Bristol Myers Squibb JapanResearch Funding: Ono Pharmaceutical Yoshiaki NakamuraHonoraria: Chugai Pharma, Guardant Health AMEA, MerckResearch Funding: Taiho Pharmaceutical (Inst), Guardant Health (Inst), Genomedia (Inst), Chugai Pharma (Inst), Seattle Genetics (Inst), Roche (Inst) Hiroya TaniguchiHonoraria: Bayer, Sanofi, Takeda, Chugai Pharma, Taiho Pharmaceutical, Lilly Japan, Merck Serono, Yakult Honsha, Medical & Biological Laboratories Co, Ltd, Bristol Myers Squibb Japan, MSD K.K, Novartis, Daiichi Sankyo, Mitsubishi Tanabe Pharma, Nippon Kayaku, Ono YakuhinResearch Funding: Dainippon Sumitomo Pharma (Inst), Array BioPharma (Inst), MSD Oncology (Inst), Ono Pharmaceutical (Inst), Daiichi Sankyo (Inst), Sysmex (Inst), Novartis (Inst), Takeda (Inst) Hisateru YasuiHonoraria: Taiho Pharmaceutical, Chugai Pharma, Bristol Myers Squibb Japan, Daiichi Sankyo, Lilly Japan, Yakult Honsha, Bayer Yakuhin, Takeda, Ono PharmaceuticalConsulting or Advisory Role: Ono PharmaceuticalResearch Funding: MSD (Inst), Daiichi Sankyo (Inst), Ono Pharmaceutical (Inst), Astellas Pharma (Inst) Taito EsakiHonoraria: Lilly, Taiho Pharmaceutical, Daiichi Sankyo, Chugai Pharma, Ono Pharmaceutical, Sanofi, MSDResearch Funding: Daiichi Sankyo (Inst), MSD (Inst), Novartis (Inst), Ono Pharmaceutical (Inst), Astellas Pharma (Inst), Lilly (Inst), Bayer (Inst), Nihonkayaku (Inst), Amgen Astellas BioPharma (Inst), Parexel (Inst), IQVIA (Inst), Quintiles (Inst), Eisai (Inst), Sumitomo Dainippon Pharma (Inst), Taiho Pharmaceutical (Inst), Pfizer (Inst), Chugai Pharma (Inst), Syneos Health (Inst) Yoshinori KagawaSpeakers' Bureau: Lilly, Sanofi, Takeda, Merck, Taiho Pharmaceutical, MSD, Chugai Pharma, Yakult Pharmaceutical, Bayer Tadamichi DendaHonoraria: Ono PharmaceuticalSpeakers' Bureau: Daiichi-Sankyo, Ono PharmaceuticalResearch Funding: Ono Pharmaceutical (Inst) Taroh SatohHonoraria: Chugai Pharma, Merck Serono, Bristol Myers Squibb, Takeda, Yakult Honsha, Lilly, Bayer Yakuhin, Ono Pharmaceutical, Merck, Astellas Pharma, Taiho Pharmaceutical, Nihonkayaku, Daiihi-SankyoConsulting or Advisory Role: Bayer Yakuhin, Lilly, Ono Pharmaceutical, Takara Bio, Merck Serono, NihonkayakuResearch Funding: Yakult Honsha (Inst), Chugai Pharma (Inst), Ono Pharmaceutical (Inst), Sanofi (Inst), Lilly (Inst), Daiichi Sankyo (Inst), Merck (Inst), Merck Serono (Inst), Gilead Sciences (Inst), Dainippon Sumitomo Pharma (Inst), IQVIA (Inst) Kentaro YamazakiHonoraria: Chugai Pharma, Daiichi Sankyo, Yakult Honsha, Takeda, Bayer, Merck Serono, Taiho Pharmaceutical, Lilly, Sanofi, Ono Pharmaceutical, MSD, Bristol Myers SquibbResearch Funding: Taiho Pharmaceutical (Inst) Yu SunakawaHonoraria: Taiho Pharmaceutical, Chugai Pharma, Takeda, Bayer Yakuhin, Bristol Myers Squibb Japan, Lilly Japan, Merck, Sysmex, MSD K.K, Ono Pharmaceutical, Daiichi Sankyo, Guardant Health, IncyteConsulting or Advisory Role: Bristol Myers Squibb Japan, MSD K.K, Daiichi SankyoResearch Funding: Taiho Pharmaceutical, Takeda, Chugai Pharma, Lilly Japan, Sanofi, Otsuka Takeshi KatoHonoraria: Chugai Pharma, Ono Pharmaceutical, Takeda, Lilly Japan, Asahi KaseiResearch Funding: Chugai Pharma Masahiro GotoHonoraria: Daiichi Sankyo Company, Ltd, Ono Pharmaceutical, Taiho Pharmaceutical, MSD K.K, Takeda, Sumitomo Dainippon Pharma Co, Ltd, Yakult Pharmaceutical, Eli Lilly Japan K.KResearch Funding: Chugai Pharma, Taiho Pharmaceutical, Nippon Kayaku Satoshi YukiHonoraria: Chugai Pharma, Takeda, Lilly Japan, Bayer Yakuhin, Taiho Pharmaceutical, Sanofi, Yakult Honsha, Bristol Myers Squibb Japan, Ono Pharmaceutical, Merck, MSD K.K Tomohiro NishinaHonoraria: Taiho Pharmaceutical, Chugai Pharma, Lilly, Merck Serono, Takeda, Bristol Myers Squibb, Ono PharmaceuticalResearch Funding: Taiho Pharmaceutical (Inst), Chugai Pharma (Inst), Dainippon Sumitomo Pharma (Inst), Lilly Japan (Inst), Merck Serono (Inst), MSD (Inst), Daiichi Sankyo (Inst), Ono Pharmaceutical (Inst), Eisai (Inst) Eiji OkiSpeakers' Bureau: Chugai Pharma, Lilly Japan, Takeda, Ono Pharmaceutical, Bristol Myers Squibb Japan Eiji ShinozakiHonoraria: Yakult Honsha, Merck Serono, Chugai Pharma, Takeda, Sanofi, Lilly, Taiho Pharmaceutical, Daiichi Sankyo/UCB Japan Naoki TakahashiHonoraria: Ono Pharmaceutical, Bristol Myers Squibb, Taiho Pharmaceutical Akihito TsujiSpeakers' Bureau: Chugai Pharma, Taiho Pharmaceutical, Merck Serono, Takeda Pharmaceutical Company Limited, Lilly Japan, Bristol Myers Squibb Corporation, SanofiResearch Funding: Taiho Pharmaceutical Co, Ltd (Inst), Sanofi (Inst), Ono Pharmaceutical (Inst) Justin I. OdegaardEmployment: Guardant HealthStock and Other Ownership Interests: Guardant Health Takayuki YoshinoHonoraria: Chugai Pharma, Merck, Bayer Yakuhin, Ono Pharmaceutical, MSD K.KResearch Funding: MSD (Inst), Daiichi Sankyo Company, Ltd (Inst), Ono Pharmaceutical (Inst), Taiho Pharmaceutical (Inst), Amgen (Inst), Sanofi (Inst), Pfizer (Inst), Genomedia (Inst), Sysmex (Inst), Nippon Boehringer Ingelheim (Inst), Chugai Pharma (Inst)No other potential conflicts of interest were reported.

Purpose: Earlier detection of cancer recurrence using circulating tumor DNA (ctDNA) to detect molecular residual disease (MRD) has the potential to dramatically affect cancer management. We review evidence supporting the use of ctDNA as a biomarker for detection of MRD and highlight the potential impact that ctDNA testing could have on the conduct of clinical trials., Methods: We searched the literature using MEDLINE (via PubMed) for articles from January 1, 2000, focusing on studies that assessed ctDNA as a predictor of cancer recurrence. Broadly focused searches on ctDNA and cancer were also performed to provide additional background information. www.clinialtrials.gov was searched to identify trials that incorporate ctDNA testing., Results: Numerous studies across different cancer types indicate that ctDNA-based MRD detection predicts recurrence with high sensitivity and specificity, and with lead times that precede standard imaging by up to 12 months. Recently, ctDNA testing has started being used to enroll MRD-positive patients at high risk of recurrence into trials, promising gains in statistical power that allow clinical utility to be demonstrated with smaller cohorts. Trials where ctDNA testing based-MRD detection is used to stratify patients into low or high-risk categories for treatment assignment are also ongoing. In addition, there is increasing evidence supporting the use of ctDNA dynamics or clearance as a surrogate end point, which could significantly reduce trial duration., Conclusion: ctDNA-based trial enrichment across many cancers seems likely to become increasingly common for cost- and time-reduction benefits. Trial efficiency could also benefit from using ctDNA as a surrogate end point, leading to accelerated approval of new therapeutics. A clear demonstration of efficacy from trials that use ctDNA-based MRD detection to assign treatment could transform clinical practice., Competing Interests: Pashtoon M. KasiConsulting or Advisory Role: Taiho Pharmaceutical (Inst), Ipsen (Inst), Natera, Foundation Medicine, AstraZeneca, MSD Oncology, Tempus, Bayer, Lilly, Delcath Systems, Axiom Healthcare Strategies, Inflecton Point Biomedical Advisors, QED Therapeutics, Boston Healthcare AssociatesResearch Funding: Bristol Myers Squibb (Inst), Advanced Accelerator Applications (Inst), Array BioPharma (Inst), Celgene (Inst), Tersera (Inst), Boston Scientific (Inst)Travel, Accommodations, Expenses: AstraZeneca Gordon FehringerEmployment: NateraStock and Other Ownership Interests: NateraConsulting or Advisory Role: Natera Hiroya TaniguchiHonoraria: Bayer, Sanofi, Takeda, Chugai Pharma, Taiho Pharmaceutical, Lilly Japan, Merck Serono, Yakult Honsha, Medical & Biological Laboratories Co, Ltd, Bristol Myers Squibb Japan, MSD K.K, Novartis, Daiichi Sankyo, Mitsubishi Tanabe Pharma, Nippon Kayaku, Ono YakuhinResearch Funding: Dainippon Sumitomo Pharma (Inst), Array BioPharma (Inst), MSD Oncology (Inst), Ono Pharmaceutical (Inst), Daiichi Sankyo (Inst), Sysmex (Inst), Novartis (Inst), Takeda (Inst) Naureen StarlingHonoraria: Lilly, MSD Oncology, Merck Serono, Pierre Fabre, SERVIER, GlaxoSmithKline, Amgen, NovartisConsulting or Advisory Role: SERVIER, AstraZeneca, Pfizer, MSD, Novartis Pharmaceuticals UK Ltd, MSD OncologyResearch Funding: AstraZeneca (Inst), Pfizer/EMD Serono (Inst), BMS (Inst)Travel, Accommodations, Expenses: MSD Oncology, AstraZeneca, BMS, Lilly, Merck, Roche Yoshiaki NakamuraResearch Funding: Taiho Pharmaceutical (Inst), Guardant Health (Inst), Genomedia (Inst), Chugai Pharma (Inst), Seattle Genetics (Inst), Roche Diagnostics Japan (Inst) Daisuke KotaniHonoraria: Takeda, Chugai Pharma, Lilly Japan, Merck Serono, Sysmex, Taiho Pharmaceutical, Ono Pharmaceutical, Bristol Myers Squibb Japan, MSD, Daiichi Sankyo/UCB JapanResearch Funding: Ono Pharmaceutical (Inst), MSD (Inst), Novartis (Inst), Janssen (Inst), IQvia (Inst), Syneos Health (Inst), CMIC (Inst) Thomas PowlesConsulting or Advisory Role: Bristol Myers Squibb, Merck, AstraZeneca, Ipsen, Pfizer, Novartis, Incyte, Seattle Genetics, Roche, Exelixis, MSD, Merck Serono, Astellas Pharma, Johnson & Johnson, EisaiResearch Funding: AstraZeneca, Roche, Bristol Myers Squibb, Exelixis, Ipsen, Merck, MSD, Novartis, Pfizer, Seattle Genetics, Merck Serono, Astellas Pharma, Johnson & Johnson, EisaiTravel, Accommodations, Expenses: Pfizer, MSD, AstraZeneca, Roche, Ipsen Bob T. LiResearch Funding: Roche/Genentech (Inst), AstraZeneca (Inst), GRAIL (Inst), Daiichi Sankyo (Inst), Hengrui Therapeutics (Inst), Guardant Health (Inst), Amgen (Inst), Lilly (Inst), MORE Health (Inst), Bolt Biotherapeutics (Inst).Patents, Royalties, Other Intellectual Property: US62/514,661 (Inst), US62/685,057 (Inst), Karger Publishers - Book royalty, Shanghai Jiao Tong University Press - Book royaltyTravel, Accommodations, Expenses: MORE Health, Jiangsu Hengrui MedicineUncompensated Relationships: Amgen, AstraZeneca, Genentech, Lilly, Boehringer Ingelheim, Daiichi Sankyo Lajos PusztaiHonoraria: bioTheranostics, Natera, OncoCyte, AthenexConsulting or Advisory Role: H3 Biomedicine, Merck, Novartis, Seattle Genetics, Syndax, AstraZeneca, Roche/Genentech, Bristol Myers Squibb, Clovis Oncology, Immunomedics, Eisai, Almac Diagnostics, PfizerResearch Funding: Merck (Inst), Genentech (Inst), Seattle Genetics (Inst), AstraZeneca (Inst), Bristol Myers Squibb (Inst), Pfizer (Inst)Travel, Accommodations, Expenses: AstraZenecaUncompensated Relationships: NanoString Technologies, Foundation MedicineOpen Payments Link: https://openpaymentsdata.cms.gov/physician/110878 Vasily N. AushevEmployment: NateraStock and Other Ownership Interests: NateraTravel, Accommodations, Expenses: Natera Ekaterina KalashnikovaEmployment: NateraStock and Other Ownership Interests: NateraTravel, Accommodations, Expenses: Natera Shruti SharmaEmployment: NateraStock and Other Ownership Interests: Natera Meenakshi MalhotraEmployment: NateraStock and Other Ownership Interests: Natera Zachary P. DemkoEmployment: NateraStock and Other Ownership Interests: Natera Alexey AleshinEmployment: NateraLeadership: NateraStock and Other Ownership Interests: NateraConsulting or Advisory Role: Mission BioTravel, Accommodations, Expenses: Natera Angel RodriguezEmployment: NateraLeadership: NateraStock and Other Ownership Interests: Natera Paul R. BillingsEmployment: NateraLeadership: Biological Dynamics, OmniSeq, Alveo Technologies, Mission BioStock and Other Ownership Interests: Natera, Trovagene, Biological Dynamics, OmniSeq, Alveo TechnologiesConsulting or Advisory Role: Bethesda Group, Guidepoint Global Axel GrotheyHonoraria: Elsevier, Aptitude Health, IMEDEXConsulting or Advisory Role: Genentech/Roche, Bayer (Inst), Bristol Myers Squibb (Inst), Lilly (Inst), Boston Biomedical (Inst), Amgen (Inst), Array BioPharma (Inst), Daiichi Sankyo (Inst), OBI PharmaResearch Funding: Genentech/Roche (Inst), Bayer (Inst), Pfizer (Inst), Eisai (Inst), Lilly (Inst), Boston Biomedical (Inst), Daiichi Sankyo (Inst), Array BioPharma (Inst).Travel, Accommodations, Expenses: Genentech/Roche, Bayer Julien TaiebConsulting or Advisory Role: Roche, Merck KGaA, Amgen, SERVIER, MSD, Pierre Fabre, NovartisSpeakers' Bureau: SERVIER, Amgen, Roche/Genentech, Sanofi, Merck, Lilly, MSD, Pierre Fabre David CunninghamStock and Other Ownership Interests: OVIBIOConsulting or Advisory Role: OVIBIOResearch Funding: Celgene (Inst), MedImmune (Inst), Bayer (Inst), 4SC (Inst), Clovis Oncology (Inst), Lilly (Inst), Roche (Inst), Leap Oncology (Inst). Takayuki YoshinoHonoraria: Chugai Pharma, Merck, Bayer Yakuhin, Ono Pharmaceutical, Lilly, Taiho PharmaceuticalResearch Funding: Chugai Pharma (Inst), MSD (Inst), DAIICHI SANKYO COMPANY, LIMITED (Inst), PAREXEL International Inc (Inst), Ono Pharmaceutical (Inst), Taiho Pharmaceutical (Inst), Amgen (Inst), Sanofi (Inst). Scott KopetzThis author is a member of the JCO Precision Oncology Editorial Board. Journal policy recused the author from having any role in the peer review of this manuscript.Stock and Other Ownership Interests: MolecularMatch, Lutris, Iylon, Frontier MedicinesConsulting or Advisory Role: Genentech, EMD Serono, Merck, Holy Stone Healthcare, Novartis, Lilly, Boehringer Ingelheim, Boston Biomedical, AstraZeneca/MedImmune, Bayer Health, Pierre Fabre, EMD Serono, Redx Pharma, Ipsen, Daiichi Sankyo, Natera, HalioDx, Lutris, Jacobio, Pfizer, Repare Therapeutics, Inivata, GlaxoSmithKline, Jazz Pharmaceuticals, Iylon, Xilis, AbbVie, Amal Therapeutics, Gilead Sciences, Mirati Therapeutics, Flame Biosciences, Servier, Carina Biotech, Bicara Therapeutics, Endeavor BioMedicines, Numab, Johnson & Johnson/Janssen, Genomic Health, Frontier MedicinesResearch Funding: Sanofi, Biocartis, Guardant Health, Array BioPharma, Genentech/Roche, EMD Serono, MedImmune, Novartis, Amgen, Lilly, Daiichi SankyoNo other potential conflicts of interest were reported.

Comprehensive genomic profiling enables the detection of genomic biomarkers in advanced solid tumors. However, efficient patient screening for the success of precision oncology remains challenging due to substantial barriers, such as genotyping costs and accessibility to matched therapies. To address these challenges, we launched GI-SCREEN, a nationwide gastrointestinal cancer genomic screening project within the SCRUM-Japan network in 2015 with the specific purpose of matching patients with a diverse portfolio of affiliated interventional targeted therapy trials. Subsequently, we initiated the molecular profiling projects GOZILA, MONSTAR-SCREEN-1, and MONSTAR-SCREEN-2, which incorporate tissue and plasma multiomics approaches to accurately identify patients with advanced solid tumors who would benefit from matched therapies. These projects have led to a significant increase in patient participation in targeted clinical trials and the approval of several therapeutics and companion diagnostics. Additionally, clinicogenomic analyses utilizing the SCRUM-Japan database have provided new insights into the molecular mechanisms of advanced solid tumors. In this review, we describe the path to the realization of cancer precision medicine for patients with advanced solid tumors based on the SCRUM-Japan GI-SCREEN and MONSTAR-SCREEN platforms., (© 2021 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.)

The applicability of circulating tumor DNA (ctDNA) genotyping to inform enrollment of patients with cancer in clinical trials has not been established. We conducted a phase 2 trial to evaluate the efficacy of pertuzumab plus trastuzumab for metastatic colorectal cancer (mCRC), with human epidermal growth factor receptor 2 (HER2) amplification prospectively confirmed by tumor tissue or ctDNA analysis ( UMIN000027887 ). HER2 amplification was confirmed in tissue and/or ctDNA in 30 patients with mCRC. The study met the primary endpoint with a confirmed objective response rate of 30% in 27 tissue-positive patients and 28% in 25 ctDNA-positive patients, as compared to an objective response rate of 0% in a matched real-world reference population treated with standard-of-care salvage therapy. Post hoc exploratory analyses revealed that baseline ctDNA genotyping of HER2 copy number and concurrent oncogenic alterations adjusted for tumor fraction stratified patients according to efficacy with similar accuracy to tissue genotyping. Decreased ctDNA fraction 3 weeks after treatment initiation associated with therapeutic response. Pertuzumab plus trastuzumab showed similar efficacy in patients with mCRC with HER2 amplification in tissue or ctDNA, showing that ctDNA genotyping can identify patients who benefit from dual-HER2 blockade as well as monitor treatment response. These findings warrant further use of ctDNA genotyping in clinical trials for HER2-amplified mCRC, which might especially benefit patients in first-line treatment., (© 2021. The Author(s).)

Purpose: FGFR2 amplification is associated with poor prognosis in advanced gastric cancer and its subclonal heterogeneity has been revealed. Here, we examined whether circulating tumor DNA (ctDNA) was useful for detecting FGFR2 amplification and co-occurring resistance mechanisms in advanced gastric cancer., Experimental Design: We assessed genomic characteristics of FGFR2 -amplified advanced gastric cancer in a nationwide ctDNA screening study. We also analyzed FGFR2 amplification status in paired tissue and plasma samples with advanced gastric cancer. In addition, we examined patients with FGFR2 -amplified advanced gastric cancer identified by ctDNA sequencing who received FGFR inhibitors., Results: FGFR2 amplification was more frequently detected by ctDNA sequencing in 28 (7.7%) of 365 patients with advanced gastric cancer than by tissue analysis alone (2.6%-4.4%). FGFR2 amplification profiling of paired tissue and plasma revealed that FGFR2 amplification was detectable only by ctDNA sequencing in 6 of 44 patients, which was associated with a worse prognosis. Two patients in whom FGFR2 amplification was detected by ctDNA sequencing after tumor progression following previous standard chemotherapies but not by pretreatment tissue analysis had tumor responses to FGFR inhibitors. A third patient with FGFR2 and MET co-amplification in ctDNA showed a limitation of benefit from FGFR inhibition, accompanied by a marked increase in the MET copy number., Conclusions: ctDNA sequencing identifies FGFR2 amplification missed by tissue testing in patients with advanced gastric cancer, and these patients may respond to FGFR inhibition. The utility of ctDNA sequencing warrants further evaluation to develop effective therapeutic strategies for patients with FGFR2 -amplified advanced gastric cancer., (©2021 The Authors; Published by the American Association for Cancer Research.)

To implement cancer precision medicine based on genomic alterations, tumor tissue genomic profiling using next generation sequencing(NGS)has been reimbursed in 2019, resulting in simultaneous measurement of multiple biomarkers and genomic abnormalities in clinical practice in Japan. However, NGS analysis of tumor tissue has several limitations, including long turnaround time, and difficulty in capturing heterogeneity and longitudinal genotyping. Recently, liquid biopsy has been developed to assess tumor status by analyzing body fluids, such as blood and urine, without the use of tumor tissue. In particular, analysis of circulating tumor DNA(ctDNA)is one of the most advanced technique for liquid biopsy in the world. Our study demonstrated that ctDNA analysis led the shorter turnaround time and acceleration of the trial enrollment in advanced gastrointestinal cancer compared to tissue analysis. Tissue and ctDNA analysis need to be used based on the characteristics of both assays in cancer precision medicine for patients with advanced gastrointestinal cancer in the future.

Background: The optimal perioperative management of patients who undergo hepatectomy for resectable colorectal liver metastases (CRLM) remains unclear due to the lack of reliable methods to stratify the risk of recurrence., Methods: A single-center retrospective study was performed to investigate the impact of preoperative circulating tumor DNA (ctDNA) on survival outcomes of patients who underwent initial hepatectomy for solitary resectable CRLM between January 2005 and December 2017 using the comprehensive genotyping platform Guardant360 ® ., Results: Of 212 patients who underwent initial hepatectomy for solitary resectable CRLM, 40 patients for whom pre-hepatectomy plasma was available underwent ctDNA analysis. Among them, 32 (80%) had at least 1 somatic alteration in their ctDNA, while the other 8 (20%) had no detectable ctDNA. Among the patients with undetectable ctDNA, only one had recurrence and none died during a median follow-up period of 39.0 months. The recurrence-free survival was significantly shorter in patients who were positive for ctDNA than in those who were negative for ctDNA [median, 12.5 months vs not reached (NR); HR, 7.6; P = 0.02]. The overall survival also tended to be shorter in patients who were positive for ctDNA than those who were negative for ctDNA (median, 78.1 months vs NR; P = 0.14; HR not available)., Conclusions: In patients undergoing hepatectomy for solitary resectable CRLM, the absence of detectable preoperative ctDNA identified patients with a high chance for a cure. Risk stratification according to preoperative ctDNA analysis may be an effective tool that can improve the perioperative management of these patients.

Circulating tumor DNA (ctDNA)-based next-generation sequencing (NGS) assays have advantages over classic tissue-based analyses because of their low invasiveness and availability of repeated sampling. Because of the low incidence of target gene alterations such as HER2 or BRAF V600E in gastrointestinal cancers, very large screening platforms are needed to develop genome-based clinical trials. For those reasons, ctDNA-based screening studies are being actively conducted; among them are the GOZILA (Guardant Originates in Zipangu Liquid biopsy Arrival) study in Japan and the COLOMATE (COlorectal Cancer Liquid BiOpsy Screening Protocol for Molecularly Assigned ThErapy) study in the United States. Although only patients with metastatic colorectal cancer (mCRC) who had previously received standard chemotherapies are eligible for the COLOMATE study, patients with various types of solid tumors at any line of treatment are eligible for GOZILA. This broad coverage of the eligible population allows a target of 5000 patients. By contrast, effective screening of selected candidate patients for companion trials using rapid turnaround time by ctDNA-based NGS assay is the key for COLOMATE. The companion trials of targeted therapies in mCRC are similar between GOZILA and COLOMATE. Both studies have identified patients eligible for studies by examining ERBB2 (HER2), BRAF V600E, BRAF non-V600E, and FGFR alterations, as well as MET amplification and rechallenge with anti-EGFR antibodies. The existence of various companion trials for common alterations that can be potential therapy targets on the 2 platforms can lead to future international collaboration.

Adjuvant chemotherapy has reduced the risk of tumor recurrence and improved survival in patients with resected colorectal cancer. Potential utility of circulating tumor DNA (ctDNA) prior to and post surgery has been reported across various solid tumors. We initiated a new type of adaptive platform trials to evaluate the clinical benefits of ctDNA analysis and refine precision adjuvant therapy for resectable colorectal cancer, named CIRCULATE-Japan including three clinical trials. The GALAXY study is a prospectively conducted large-scale registry designed to monitor ctDNA for patients with clinical stage II to IV or recurrent colorectal cancer who can undergo complete surgical resection. The VEGA trial is a randomized phase III study designed to test whether postoperative surgery alone is noninferior to the standard therapy with capecitabine plus oxaliplatin for 3 months in patients with high-risk stage II or low-risk stage III colon cancer if ctDNA status is negative at week 4 after curative surgery in the GALAXY study. The ALTAIR trial is a double-blind, phase III study designed to establish the superiority of trifluridine/tipiracil as compared with placebo in patients with resected colorectal cancer who show circulating tumor-positive status in the GALAXY study. Therefore, CIRCULATE-Japan encompasses both "de-escalation" and "escalation" trials for ctDNA-negative and -positive patients, respectively, and helps to answer whether measuring ctDNA postoperatively has prognostic and/or predictive value. Our ctDNA-guided adaptive platform trials will accelerate clinical development toward further precision oncology in the field of adjuvant therapy. Analysis of ctDNA status could be utilized as a predictor of risk stratification for recurrence and to monitor the effectiveness of adjuvant chemotherapy. ctDNA is a promising, noninvasive tumor biomarker that can aid in tumor monitoring throughout disease management., (© 2021 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.)

Cancer precision medicine has become widespread in the world. In Japan, genomic profiling tumor tissues using next generation sequencing(NGS)has been reimbursed to enable simultaneous measurement of multiple biomarkers and genomic abnormalities in clinical practice. However, NGS analysis of tumor tissue has several problems, including long turnaround time, and difficulty in capturing heterogeneity and longitudinal genotyping. Liquid biopsy, an advanced technique that has been developed in recent years, can assess the status of tumors using samples of body fluids, such as blood and urine, without the use of tumor tissue. In particular, circulating tumor DNA(ctDNA), which is released from tumor cells into the blood by apoptosis and necrosis, can be used to select molecularly targeted therapies, monitor therapeutic efficacy, and determine risk of recurrence and select for adjuvant chemotherapy by assessment of minimal residual disease(MRD). In this review, we outline the usefulness, disadvantages and future perspectives of ctDNA analysis.

Comprehensive genomic profiling enables genomic biomarker detection in advanced solid tumors. Here, to evaluate the utility of circulating tumor DNA (ctDNA) genotyping, we compare trial enrollment using ctDNA sequencing in 1,687 patients with advanced gastrointestinal (GI) cancer in SCRUM-Japan GOZILA (no. UMIN000016343), an observational ctDNA-based screening study, to enrollment using tumor tissue sequencing in the same centers and network (GI-SCREEN, 5,621 patients). ctDNA genotyping significantly shortened the screening duration (11 versus 33 days, P < 0.0001) and improved the trial enrollment rate (9.5 versus 4.1%, P < 0.0001) without compromising treatment efficacy compared to tissue genotyping. We also describe the clonal architecture of ctDNA profiles in ~2,000 patients with advanced GI cancer, which reinforces the relevance of many targetable oncogenic drivers and highlights multiple new drivers as candidates for clinical development. ctDNA genotyping has the potential to accelerate innovation in precision medicine and its delivery to individual patients.

Comprehensive genomic profiling using next-generation sequencing (NGS) enables the identification of multiple genomic biomarkers established in advanced gastrointestinal (GI) cancers. However, tissue-based NGS has limitations, such as long turnaround time and failure to detect tumour heterogeneity. Recently, the analysis of circulating tumour DNA (ctDNA) using polymerase chain reaction-based or NGS-based methods has demonstrated the capability to detect genomic alterations with high accuracy compared with tumour tissue analysis with short turnaround time and identify heterogeneous resistance mechanisms. Furthermore, ctDNA analysis can be repeatedly performed on disease progression to clarify resistant clones. Clinical trials that test the outcome of a selected targeted therapy based on a ctDNA result are ongoing to prospectively evaluate the clinical utility of ctDNA analysis. Furthermore, the improvement of ctDNA analysis beyond current technical limits of mutation-based ctDNA detection methods has expanded the potential for detecting the presence of tumours in patients with no clinically evident disease, such as minimal residual disease and early cancer. Although a careful understanding of the advantages and limitations are required and further prospective studies are needed, the ctDNA analysis has the potential to overcome several challenges in the treatment of various types of cancers at all stages, including GI cancers., Competing Interests: Competing interests: YN reports research funding from Taiho Pharmaceutical. KS reports paid consulting or advisory roles for Astellas, Lilly, Bristol-Myers Squibb, Takeda, Pfizer, Ono and MSD; honoraria from Novartis, AbbVie and Yakult and research funding from Astellas, Lilly, Ono, Sumoitomo Dainippon, Daiichi Sankyo, Taiho, Chugai, MSD and Medi Science., (© Author (s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. Published by BMJ on behalf of the European Society for Medical Oncology.)

Purpose: To analytically and clinically validate microsatellite instability (MSI) detection using cell-free DNA (cfDNA) sequencing., Experimental Design: Pan-cancer MSI detection using Guardant360 was analytically validated according to established guidelines and clinically validated using 1,145 cfDNA samples for which tissue MSI status based on standard-of-care tissue testing was available. The landscape of cfDNA-based MSI across solid tumor types was investigated in a cohort of 28,459 clinical plasma samples. Clinical outcomes for 16 patients with cfDNA MSI-H gastric cancer treated with immunotherapy were evaluated., Results: cfDNA MSI evaluation was shown to have high specificity, precision, and sensitivity, with a limit of detection of 0.1% tumor content. In evaluable patients, cfDNA testing accurately detected 87% (71/82) of tissue MSI-H and 99.5% of tissue microsatellite stable (863/867) for an overall accuracy of 98.4% (934/949) and a positive predictive value of 95% (71/75). Concordance of cfDNA MSI with tissue PCR and next-generation sequencing was significantly higher than IHC. Prevalence of cfDNA MSI for major cancer types was consistent with those reported for tissue. Finally, robust clinical activity of immunotherapy treatment was seen in patients with advanced gastric cancer positive for MSI by cfDNA, with 63% (10/16) of patients achieving complete or partial remission with sustained clinical benefit., Conclusions: cfDNA-based MSI detection using Guardant360 is highly concordant with tissue-based testing, enabling highly accurate detection of MSI status concurrent with comprehensive genomic profiling and expanding access to immunotherapy for patients with advanced cancer for whom current testing practices are inadequate. See related commentary by Wang and Ajani, p. 6887 ., (©2019 American Association for Cancer Research.)

Multiple genomic changes caused by clonal evolution induced by therapeutic pressure and corresponding intratumoral heterogeneity have posed great challenges for personalized therapy against metastatic colorectal cancer (mCRC) in the past decade. Liquid biopsy has emerged as an excellent molecular diagnostic tool for assessing predominant spatial and temporal intratumoral heterogeneity with minimal invasiveness.Previous studies have revealed that genomic alterations in RAS , BRAF , ERBB2 , and MET , as well as other cancer-related genes associated with resistance to anti-epidermal growth factor receptor (EGFR) therapy, can be analyzed with high diagnostic accuracy by circulating tumor DNA (ctDNA) analysis. Furthermore, by longitudinally monitoring ctDNAs during anti-EGFR therapy, the emergence of genomic alterations can be detected as acquired resistance mechanisms in specific genes, mainly those associated with the mitogen-activated protein kinase signaling pathway. Analysis of ctDNA can also identify predictive biomarkers to immune checkpoint inhibitors, such as mutations in mismatch repair genes, microsatellite instability-high phenotype, and tumor mutation burden. Some prospective clinical trials evaluating targeted agents for genomic alterations in ctDNA or exploring resistance biomarkers by monitoring of ctDNA are ongoing.To determine the value of ctDNA analysis for decision-making by more accurate molecular marker-based selection of patients and identification of resistance mechanisms to targeted therapies or sensitive biomarkers for immune checkpoint inhibitors, clinical trials must be refined to evaluate the efficacy of study treatment in patients with targetable genomic alterations confirmed by ctDNA analysis, and resistance biomarkers should be explored by monitoring ctDNA in large-scale clinical trials. In the near future, ctDNA analysis will play an important role in precision medicine for mCRC. IMPLICATIONS FOR PRACTICE: Treatment strategies for metastatic colorectal cancer (mCRC) are determined according to the molecular profile, which is confirmed by analyzing tumor tissue. Analysis of circulating tumor DNA (ctDNA) may overcome the limitations of tissue-based analysis by capturing spatial and temporal intratumoral heterogeneity of mCRC. Clinical trials must be refined to test the value of ctDNA analysis in patient selection and identification of biomarkers. This review describes ctDNA analysis, which will have an important role in precision medicine for mCRC., Competing Interests: Disclosures of potential conflicts of interest may be found at the end of this article., (© AlphaMed Press 2018.)

"NeoRAS WT" refers to the loss of RAS mutations (MTs) following first-line treatment in metastatic colorectal cancer (mCRC). We evaluate the incidence and clinicopathological characteristics of NeoRAS WT mCRC using next-generation sequencing of plasma circulating tumor DNA. Patients with mCRC enrolled in the GOZILA study initially diagnosed with tissue RAS MT mCRC and received subsequent systemic therapy are eligible. NeoRAS WT is defined as the absence of detectable RAS MT in plasma and assessed in all eligible patients (Group A) and in a subgroup with at least one somatic alteration detected in plasma (Group B). Overall, 478 patients are included. NeoRAS WT prevalence is 19.0% (91/478) in Group A and 9.8% (42/429) in Group B. Absence of liver or lymph node metastasis and tissue RAS MTs other than KRAS exon 2 MTs are significantly associated with NeoRAS WT emergence. Overall, 1/6 and 2/6 patients with NeoRAS WT treated with anti-EGFR monoclonal antibodies (mAbs) show partial response and stable disease for ≥6 months, respectively. NeoRAS WT mCRC is observed at a meaningful prevalence, and anti-EGFR mAb-based therapy may be effective. RAS mutations have been shown to be lost after first line treatment for metastatic colorectal cancer. Here, the authors leverage the GOZILA study to identify these patients and identify their association with other risk factor. [ABSTRACT FROM AUTHOR]

PURPOSE: Circulating tumor DNA (ctDNA) genotyping on the basis of next-generation sequencing (NGS) may guide targeted therapy for metastatic colorectal cancer (mCRC). However, the validity of NGS-based ctDNA genotyping for RAS/BRAF V600E mutation assessment and the efficacy of anti-EGFR and BRAF-targeted therapies on the basis of ctDNA results remains unclear. PATIENTS AND METHODS: The performance of NGS-based ctDNA genotyping for RAS/BRAF V600E mutation assessment was compared with that of a validated polymerase chain reaction–based tissue testing in patients with mCRC enrolled in the GOZILA study, a nationwide plasma genotyping study. The primary end points were concordance rate, sensitivity, and specificity. The efficacy of anti-EGFR and BRAF-targeted therapies on the basis of ctDNA were also evaluated. RESULTS: In 212 eligible patients, the concordance rate, sensitivity, and specificity were 92.9% (95% CI, 88.6 to 96.0), 88.7% (95% CI, 81.1 to 94.0), and 97.2% (95% CI, 92.0 to 99.4) for RAS and 96.2% (95% CI, 92.7 to 98.4), 88.0% (95% CI, 68.8 to 97.5), and 97.3% (95% CI, 93.9 to 99.1) for BRAF V600E, respectively. In patients with a ctDNA fraction of ≥1.0%, sensitivity rose to 97.5% (95% CI, 91.2 to 99.7) and 100% (95% CI, 80.5 to 100.0) for RAS and BRAF V600E mutations, respectively. In addition to a low ctDNA fraction, previous chemotherapy, lung and peritoneal metastases, and interval between dates of tissue and blood collection were associated with discordance. The progression-free survival of anti-EGFR therapy and BRAF-targeted treatment was 12.9 months (95% CI, 8.1 to 18.5) and 3.7 (95% CI, 1.3 to not evaluated) months, respectively, for matched patients with RAS/BRAF V600E results by ctDNA. CONCLUSION: ctDNA genotyping effectively detected RAS/BRAF mutations, especially with sufficient ctDNA shedding. Clinical outcomes support ctDNA genotyping for determining the use of anti-EGFR and BRAF-targeted therapies in patients with mCRC. Using a large-scale plasma genomic profiling program (SCRUM-Japan GOZILA), we validated ctDNA genotyping for RAS and BRAF V600E in metastatic colorectal cancer comparing with a validated tissue PCR-based testing. [ABSTRACT FROM AUTHOR]

Background: Previous clinical trials have demonstrated the potential efficacy of poly (ADP-ribose) polymerase (PARP) inhibitors (PARPis) in patients with cancer involving homologous recombination repair (HRR) gene-mutation. Moreover, HRR gene-mutated cancers are effectively treated with immune checkpoint inhibitors (ICIs) with the increase in tumor mutation burden. We have proposed to conduct a multicenter, single-arm phase II trial (IMAGENE trial) for evaluating the efficacy and safety of niraparib (PARPi) plus programmed cell death-1 inhibitor combination therapy in patients with HRR gene-mutated cancers who are refractory to ICIs therapy using a next generation sequencing-based circulating tumor DNA (ctDNA) and tumor tissue analysis. Methods: Key eligibility criteria for this trial includes HRR gene-mutated tumor determined by any cancer gene tests; progression after previous ICI treatment; and Eastern Cooperative Oncology Group Performance Status ≤ 1. The primary endpoint is the confirmed objective response rate (ORR) in all patients. The secondary endpoints include the confirmed ORR in patients with HRR gene-mutation of ctDNA using the Caris Assure (CARIS, USA). The target sample size of the IMAGENE trial is 57 patients. Biomarker analyses will be performed in parallel using the Caris Assure, proteome analysis, and T cell repertoire analysis to reveal tumor immunosurveillance in peripheral blood. Expected outcome: Our trial aims to confirm the clinical benefit of PARPi plus ICI combination therapy in ICI-resistant patients. Furthermore, through translational research, our trial will shed light on which patients would benefit from the targeted combination therapy for patients with HRR gene-mutated tumor even after the failure of ICIs. Trial registration: The IMAGENE trial: jRCT, Clinical trial no.: jRCT2051210120, Registered date: November 9, 2021. [ABSTRACT FROM AUTHOR]

Trastuzumab deruxtecan (DS-8201) is an antibody-drug conjugate composed of a humanized monoclonal anti-HER2 antibody, a cleavable tetrapeptide-based linker and a potent topoisomerase I inhibitor. The drug's efficacy has been proven in HER2-positive breast and gastric cancers. The rate of HER2 positivity in biliary tract cancer (BTC) has been reported to be 5-20%, and case reports and clinical trials have suggested that HER2 inhibitors might be active in HER2-positive BTC. Here we describe the rationale and design of the phase II HERB trial that will evaluate the efficacy and safety of trastuzumab deruxtecan in patients with HER2-expressing unresectable or recurrent BTC. The primary end point will be the centrally assessed objective response rate in HER2-positive patients. [ABSTRACT FROM AUTHOR]

PURPOSE: Circulating tumor DNA (ctDNA) genotyping may guide targeted therapy for patients with advanced GI cancers. However, no studies have validated ctDNA genotyping for microsatellite instability (MSI) assessment in comparison with a tissue-based standard. PATIENTS AND METHODS: The performance of plasma-based MSI assessment using Guardant360, a next-generation sequencing–based ctDNA assay, was compared with that of tissue-based MSI assessment using a validated polymerase chain reaction–based method in patients with advanced GI cancers enrolled in GOZILA study, a nationwide ctDNA profiling study. The primary end points were overall percent agreement, positive percent agreement (PPA), and negative percent agreement. The efficacy of immune checkpoint inhibitor therapy was also evaluated. RESULTS: In 658 patients with advanced GI cancers who underwent both plasma and tissue testing for MSI, the overall percent agreement, PPA, and negative percent agreement were 98.2% (95% CI, 96.8 to 99.1), 71.4% (95% CI, 47.8 to 88.7), and 99.1% (95% CI, 98.0 to 99.7), respectively. In patients whose plasma samples had a ctDNA fraction ≥ 1.0%, the PPA was 100.0% (15/15; 95% CI, 78.2 to 100.0). Three patients with MSI-high (MSI-H) tumors detected only by ctDNA genotyping achieved clinical benefits after receiving anti–programmed cell death 1 therapy with the progression-free survival ranging from 4.3 to 16.7 months. One patient with an aggressive cancer of an unknown primary site benefited from pembrolizumab after rapid detection of MSI-H by ctDNA genotyping. CONCLUSION: ctDNA genotyping was able to detect MSI with high concordance to validated tissue-based MSI testing, especially in patients with tumors that have sufficient ctDNA shedding. Furthermore, ctDNA genotyping enabled identification of patients with MSI-H tumors who benefited from immune checkpoint inhibitor treatment. [ABSTRACT FROM AUTHOR]

Chromosomal instability is one of the characteristics of gastric cancer (GC)[1],[2] associated with frequent amplifications of receptor tyrosine kinase (RTK)-related genes. We present a patient with I EGFR i -amplified GC who acquired substantial numbers of I EGFR i mutations and I MET i amplification during the cetuximab treatment as detected by serial ctDNA sequencing. The number of I EGFR i mutations (range, 1-7; Fig 3C) or known actionable I EGFR i mutations (range, 1-6; Fig 3D) were lower than those seen in our GC patient with 22 I EGFR i mutations, including seven known actionable mutations. [Extracted from the article]