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‹ Sat · 13 Jun 2026
Near-term implementable finding

Real-world cell-free circulating tumor DNA (ctDNA) analysis identifies CDK4/6 inhibitor resistance and tumor evolution in HR+ advanced breast cancer

Blood tests can identify pre-treatment cancer mutations that predict how breast cancer will respond to hormone therapy, guiding smarter treatment sequencing.

Large real-world ctDNA database analysis demonstrates that a CDK4/6i resistance mutation signature identified pre-treatment predicts significantly worse survival outcomes in HR+ metastatic breast cancer, with ESR1 and RB1 alterations further enriched after CDK4/6i exposure. Findings support ctDNA-based resistance profiling before CDK4/6i initiation to guide personalized treatment sequencing.

What the study was

Study design
Real-world retrospective clinical-genomic database analysis
Population
HR+/HER2- metastatic breast cancer patients, CDK4/6i + ET treated
Category
Genomics/Precision Medicine
Maturity
Validated
Journal
NPJ Breast Cancer

Why it surfaced

Large real-world Guardant database; ctDNA resistance panel directly implementable pre-CDK4/6i for HR+ mBC treatment sequencing.

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