Adverse events of self-expandable metal stent placement for malignant distal biliary obstruction: a large multicenter study

Abstract

Background and aimEndoscopic placement of self-expandable metal stents (SEMSs) for malignant distal biliary obstruction (MDBO) may be accompanied by several types of adverse events. The present study analyzed the adverse events occurring after SEMS placement for MDBO. MethodsThe present study retrospectively investigated the incidence and types of adverse events in patients who underwent SEMS placement for MDBO between April 2018 and March 2021 at 26 hospitals. Risk factors for acute pancreatitis, cholecystitis, and recurrent biliary obstruction (RBO) were evaluated by univariate and multivariate analyses. ResultsOf the 1425 patients implanted with SEMS for MDBO, 228 (16.0%) and 393 (27.6%) experienced early adverse events and RBO, respectively. Pancreatic duct without tumor involvement (p = 0.023), intact papilla (p = 0.025), and SEMS placement across the papilla (p = 0.037) were independent risk factors for acute pancreatitis. Tumor involvement in the orifice of the cystic duct (OCD) was an independent risk factor for cholecystitis (p < 0.001). Fully and partially covered SEMSs were independent risk factors for food impaction and/or sludge. Fully covered SEMS was an independent risk factor for stent migration. Uncovered SEMS and laser-cut SEMS were independent risk factors for tumor ingrowth. ConclusionsPancreatic duct without tumor involvement, intact papilla, and SEMS placement across the papilla were independent risk factors for acute pancreatitis, and tumor involvement to the OCD was an independent risk factor for cholecystitis. The risk factors for food impaction and/or sludge, stent migration, and tumor ingrowth differed among types of SEMS.