Circulating tumor DNA in breast cancer: updates from SABCS 2025.
Summary
Data from the 2025 San Antonio Breast Cancer Symposium highlight the expanding role of circulating tumor DNA (ctDNA) in breast cancer management. ctDNA is now being utilized to guide therapeutic decisions, particularly in advanced hormone receptor-positive breast cancer. The SERENA-6 trial demonstrated that ctDNA-detected ESR1 mutations enabled adaptation of endocrine therapy, leading to improved clinical outcomes. Furthermore, in early-stage disease, ctDNA identifies minimal residual disease (MRD) and patients at high risk of recurrence. These advancements position ctDNA as a crucial biomarker for precision oncology and dynamic treatment adaptation.
Analysis
These findings are of paramount importance for clinical practice and translational research in oncology. They confirm that ctDNA is moving beyond its prognostic role to become a direct therapeutic decision-making tool, enabling greater personalization of treatments. The ability to detect specific alterations like ESR1 mutations to modulate endocrine therapy, or to identify MRD to refine recurrence risk stratification, paves the way for more targeted therapeutic escalation or de-escalation strategies. This promises to optimize patient outcomes by avoiding unnecessary treatments and intensifying care for those who will benefit most.