Fig. 3

Concentrations of ctDNA in bile samples from six patients with BTC. (A) Four patients with wild-type KRAS had ctDNA concentrations below the cut-off value of 1.5 copies/µL. (B) Two patients with KRAS mutations exhibited ctDNA concentrations above the cut-off value. No significant changes in ctDNA concentrations were observed over time for either group (Repeated measures ANOVA; P = 0.926 and P = 0.399, respectively).