Advanced cannulation techniques vs early EUS-guided biliary drainage in case of difficult biliary cannulation in patients with distal malignant biliary obstruction: an international multi-center propensity score-matched analysis (the ACT-EUS study)

Aims Biliary drainage (BD) in distal malignant biliary obstruction (DMBO) is often hampered by difficult biliary cannulation (DBC) during endoscopic retrograde cholangiopancreatography (ERCP). Advanced cannulation techniques (aERCP) may overcome DBC but still fail in up to 15% of cases, increasing the risk of adverse events (AEs). Early endoscopic ultrasound-guided BD (eEUS-BD) is a potential alternative. The aim of this study is to directly compare safety and efficacy of EUS-BD and aERCP [ 1 ] [ 2 ] [ 3 ] [ 4 ] [ 5 ] [ 6 ] [ 7 ] [ 8 ] [ 9 ] [ 10 ] [ 11 ] [ 12 ] [ 13 ] [ 14 ] [ 15 ] [ 16 ] [ 17 ] [ 18 ] [ 19 ] [ 20 ] [ 21 ] [ 22 ] [ 23 ] [ 24 ]. Methods This is a retrospective, multicentric study (30 centres in United States, Canada, Europe), including patients with DMBO and common bile duct (CBD) diameter>12 mm treated between 2019 and 2024. DBC cases managed with either eEUS-BD or aERCP were analysed. A 1:2 propensity score-matched cohort was generated to ensure comparability, with regression modelling and inverse probability of treatment weighting (IPTW) performed as sensitivity analyses. AEs rate was the primary outcome; secondary outcomes included BD failure and clinical success. Results Standard cannulation failed in 2066/10,738 (19.2%) ERCPs. aERCP and eEUS-BD were attempted in 1733 and 333 cases, respectively. After matching, 313 patients per EUS-BD group and 626 patients per aERCP group were analyzed. AEs occurred in 18.2% of aERCPs and 9.3% of eEUS-BD (p<0.01), with post-procedural pancreatitis the most frequent AE after aERCP (55 cases, 12.0%). Both regression and IPTW confirmed the robustness of these findings on the entire cohort. Technical success was significantly lower with aERCP (82.0% vs. 95.9%, p<0.01), clinical success was comparable (94.5% vs. 96.4%, p=0.89). Conclusions In patients with DMBO and dilated CBD, eEUS-BD is associated with fewer AEs and higher technical success than aERCP, supporting its role as a safer, more effective option in DBC. Publication History Article published online: 05 June 2026 © 2026. European Society of Gastrointestinal Endoscopy. All rights reserved. Georg Thieme Verlag KG Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany