J.Jpn. Surg. Soc.. 127(3): 281-286, 2026

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Feature topic

COMPREHENSIVE GENOMIC PROFILING RESHAPING BREAST CANCER CARE: CLINICAL IMPACT, UNMET CHALLENGES, AND INSIGHTS FROM THE JBCRG-C07 REIWA TRIAL

Breast cancer care is undergoing a paradigm shift from conventional stratification by hormone receptor (HR) and HER2 status to precision treatment guided by actionable genomic alterations. Comprehensive genomic profiling (CGP) interrogates hundreds of genes in parallel, enabling molecularly matched and tumor-agnostic treatment selection, accelerating clinical trial enrollment, and flagging potential hereditary cancer predisposition, while also illuminating mechanisms of therapeutic resistance and response. Despite these promises, real-world delivery of recommended matched therapies remains suboptimal, constrained by test timing, specimen adequacy, turnaround time, patient deterioration (including declining performance status), and persistent barriers to trial and drug access. This review summarizes current international recommendations and the Japanese genomic medicine framework (expert panels and C-CAT) and focuses on the final analysis of the domestic prospective observational JBCRG-C07 (REIWA) study. It discusses practical implementation strategies for breast clinicians to translate CGP results into clinical benefit, including patient selection, specimen and timing planning, trial referral pathways, and patient communication, along with remaining challenges and future directions.

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