Systematic review and meta-analysis of circulating tumor DNA and survival in metastatic breast cancer

Metastatic breast cancer (mBC) poses a substantial clinical challenge despite advancements in diagnosis and treatment. While tissue biopsies offer a static snapshot of disease, liquid biopsy – through detection of circulating tumor (ct)DNA – provides minimally invasive real-time insight into tumor biology. A systematic review and meta-analysis reporting data from 4262 female mBC patients in 37 studies, found that baseline detection of ctDNA was associated with worse survival (HR 1.40; 95% CI 1.22-1.58). Subgroup analyses identified significant associations of TP53 and ESR1 alterations with worse survival, while PIK3CA alterations were not associated with survival outcomes. ctDNA detection was associated with worse survival, regardless of the detection method (next-generation sequencing of digital polymerase chain reaction. The authors conclude that these results suggest ctDNA detection might be a useful prognostic biomarker in mBC.