Promise of bile circulating tumor DNA in biliary tract cancers.

An explosion of technological advances has facilitated the unprecedented use of liquid biopsy methods to isolate and interrogate circulating tumor DNA for precision oncology approaches. Liquid biopsy samples are not isolated to plasma but include bodily fluids such as urine and bile. In this issue, Ohyama et al. present a prospective study of patients with biliary tract cancers who underwent cell‐free DNA (cfDNA) isolation from bile and plasma, further demonstrating the feasibility and promise of bile cfDNA for biliary tract malignancies. [ABSTRACT FROM AUTHOR]