ctDNA provides a reliable alternative to tissue genomic profiling

In a study involving 102 advanced biliary tract cancer patients, circulating tumor DNA (ctDNA) demonstrated an 84.8% sensitivity and a 79.4% positive predictive value compared to tissue genomic profiling. Targetable alterations were identified in 34.3% of patients, including mutations such as FGFR2 fusion and BRCA1/2 mutations. Notably, a novel FGFR2-TNS1 fusion was detected via ctDNA analysis, which was absent in tissue assessments. High somatic variant allele frequency correlated with poor prognosis post-chemotherapy, underscoring ctDNA’s potential as a complementary tool.