BackgroundBiliary drainage in patients managed palliatively for malignant hilar obstruction can be achieved by endoscopic transpapillary stenting using endoscopic retrograde cholangiography (ERC) or percutaneous transhepatic stent or catheter placement using percutaneous transhepatic cholangiography (PTC). This study compares ERC and PTC drainage for malignant hilar bile duct obstruction. MethodsA retrospective study of drainage procedures at two academic hospitals was conducted from 2015 to 2020. Procedural success (divided into access-, bridging-, and technical success), therapeutic success, duration of therapeutic success and complications were analysed for different Bismuth-Corlette stricture types. ResultsA total of 293 patients were included, 153 (52.2%) in the ERC group and 140 (47.8%) in the PTC group. Access and bridging success in the ERC and PTC groups were 83.5% vs. 97.2% (p < 0.001) and 90.2% vs. 84.5% (p = 0.119), respectively. Technical and therapeutic success were equivalent between the two groups (98.3% vs. 99.3%, p = 0.854 and 81.7% vs. 73.3%, p = 0.242). Duration of therapeutic success was longer after ERC drainage compared to PTC drainage (p = 0.009) with a 3-month gain in duration of therapeutic success after ERC drainage (p = 0.006, 95% CI [26–160]). Cholangitis rates were equivalent (21.4% vs. 24.7%, p = 0.530), pancreatitis was more common in the ERC group (9.4% vs. 0%, p < 0.001) and procedure-related deaths more common in the PTC group (6.0% vs. 15.8%, p < 0.001). ConclusionAlthough ERC and PTC drainage of malignant hilar obstruction were similar regarding technical and therapeutic success, ERC drainage was more durable. Outcome differences for B–C stricture types should be explored in future studies.