ctDNA Detection Outperforms Standard Surveillance in Predicting BTC Recurrence

A recent retrospective study to determine the prognostic value of serial circulating tumor DNA (ctDNA) testing has revealed its benefits as a prognostic biomarker for detecting recurrence over standard surveillance for patients with curatively resected early-stage biliary tract cancer (BTC).

The multicenter cohort study assessed relapse-free survival (RFS) in relation to ctDNA positivity in 56 patients with curatively resected stage I-III BTC. The study evaluated ctDNA sensitivity in detecting confirmed BTC recurrence, defined as either biopsy-proven recurrence or true progression based on radiographic tumor dynamics. In addition, the lead time from initial ctDNA detection to confirmed recurrence was analyzed.

With a median follow-up of 12.8 months after surgery, ctDNA detection during the molecular residual disease window was associated with significantly worse RFS (median RFS, 6.6 months vs not reached; hazard ratio [HR], 26; 95% CI, 2.6-265; P<.0001). In addition, ctDNA positivity during the surveillance period was linked to worse RFS outcomes (median RFS, 19.3 months vs not reached; HR, 20; 95% CI, 2.6-153; P<.0001).

Among 16 patients with confirmed recurrence, ctDNA accurately identified recurrence in 15 (93.8.%) with an average lead time of 3.7 months. Carbohydrate antigen 19-9 levels did not show a significant correlation with RFS (HR, 1.17; 95% CI, 0.24-5.71; P=.844), underscoring the superior prognostic value of ctDNA.

The findings of this study demonstrate the promising potential of ctDNA as a prognostic biomarker and its ability to detect recurrence earlier than standard surveillance.