Digital single-operator peroral cholangioscopy-guided biopsy sampling versus ERCP-guided brushing for indeterminate biliary strictures: a prospective, randomized, multicenter trial

Background and Aims: Accurately diagnosing indeterminate biliary strictures is challenging but important for patient prognostication and further management. Biopsy sampling under direct cholangioscopic vision might be superior to standard ERCP techniques such as brushing or biopsy sampling. Our aim was to investigate whether digital single-operator cholangioscopy (DSOC) compared with standard ERCP workup improves the diagnostic yield in patients with indeterminate biliary strictures. Methods: Patients with an indeterminate biliary stricture on the basis of MRCP were randomized to standard ERCP visualization with tissue brushing (control arm [CA]) or DSOC visualization and DSOC-guided biopsy sampling (study arm [SA]). This was a prospective, international, multicenter trial with a procedure-blinded pathologist. Results: The first sample sensitivity of DSOC-guided biopsy samples was significantly higher than ERCP-guided brushing (SA 68.2% vs CA 21.4%, P < .01). The sensitivity of visualization (SA 95.5% vs CA 66.7%, P = .02) and overall accuracy (SA 87.1% vs CA 65.5%, P = .05) were significantly higher in the SA compared with the CA, whereas specificity, positive predictive value, and negative predictive value showed no significant difference. Adverse events were equally low in both arms. Conclusions: DSOC-guided biopsy sampling was shown to be safe and effective with a higher sensitivity compared with standard ERCP techniques in the visual and histopathologic diagnosis of indeterminate biliary strictures.