Optimization of ERCP Technique to Improve the Sensitivity of Biliary Brushing: A Systematic Review and Meta-analysis.

Background and aims: Endoscopic retrograde cholangiopancreatography (ERCP) with brush cytology is an important tool in the diagnosis of hepatobiliary malignancies. However, reported sensitivity of brush cytology is suboptimal and differs markedly per study. The aim of this study is to analyze the optimal technique of endobiliary brushing during ERCP.

Methods: A systematic review and meta-analysis according was performed using Pubmed, Embase and Cochrane library, and reported reported according to the PRISMA guidelines. The intervention reported should involve ERCP, performed by the endoscopist with a comparison of different brushing techniques. The primary outcome was sensitivity for malignancy. Studies published up to December 2022 were included. Percutaneous techniques and cytological or laboratory techniques for processing of material were excluded. Bias was assessed using the Quadas-2 tool. Pooled sensitivity rates and Forest plots were analyzed for the primary outcome.

Results: A total of 16 studies were included. Three studies reported on brushing before or after dilation of a biliary stricture. No improvement in sensitivity was found. Five studies reported on alternative brush designs. This did not lead to improved sensitivity. Seven studies reported on the aspiration and analysis of bile fluid, which resulted in a 16% increase in sensitivity (95% CI 4-29%). One study reported an increased in the number of brush passes to the stricture, providing an increase in sensitivity of 20%. Substantial heterogeneity between studies was found, both methodological and statistical.

Conclusions: Increasing the number of brush-passes and sending bile fluid for cytology increases the sensitivity of biliary brushings during ERCP. Dilation before brushing or alternative brush designs did not increase sensitivity.