Impact of Endoscopic Ultrasound-guided biliary drainage on the management of difficult biliary cannulation in patients with distal malignant biliary obstruction

Background: Biliary drainage (BD) in patients with distal malignant biliary obstruction (DMBO) implies a higher risk of difficult biliary cannulation (DBC) during endoscopic retrograde cholangiopancreatography (ERCP). After standard cannulation failure, the endoscopist may proceed with advanced cannulation techniques and/or, with endoscopic ultrasound-guided biliary drainage (EUS-BD). Materials: This was a retrospective study of consecutive patients with DMBO and dilated common bile duct (CBD, > 12mm) that underwent ERCP for endoscopic BD in four European centers. The rates of DBC, technical and, clinical success, and procedure-related adverse events (AEs) were assessed. The predictive factors for AEs were also investigated through regression analysis. EUS-BD approach was considered as first option after standard cannulation failure or as final option after advanced cannulation failure. Results: A total of 1016 patients with DMBO were included in the study, with 524(51.6%) matching the definition of DBC. Clinical success was achieved in 956 cases (94.1%). One-hundred-sixty-seven patients (16,4%) experienced procedural-related AEs. Subjects with DBC showed a higher risk for AEs (p = 0.003), however, patients undergoing “early” EUS-BD showed a risk of AEs comparable to those managed with standard cannulation (p = 0.3776). The attempt of any advanced cannulation technique was independently associated with the occurrence of AEs (p = 0.001). Conclusions: The risk of AEs is higher in patients with DMBO, and DBC, this appears to be mainly related to the advanced cannulation techniques. In patients with dilated CBD (>12mm) “early” EUS-BD may minimize the risk of adverse events.