Efficacy and safety of a novel multihole fully covered self-expandable metallic stent for malignant distal biliary obstruction: Multicenter retrospective study

Objectives: Covered self-expandable metallic stents (CSEMS) are effective for managing malignant distal biliary obstruction (MDBO). However, migration is a significant problem, which requires prevention. The novel multihole fully CSEMS (MHSEMS), which features multiple small holes on the covered membrane, is expected to prevent migration. This study aimed to evaluate the efficacy and safety of MHSEMS for MDBO. Methods: This multicenter retrospective cohort study included 111 patients with MDBO who underwent MHSEMS placement between September 2022 and August 2023. The primary outcome was the recurrent biliary obstruction (RBO) rate. The secondary outcomes were adverse event (AE) rates, removability, technical and clinical success rates, and time to RBO. Results: The technical success rate was 100%, and the clinical success rate was 94.6%. AEs occurred in 34.2% of patients, with RBO in 21.0% and non-RBO AEs in 17.1%. RBO included stent migration in 1.9%, stent occlusion in 11.7% (including ingrowth in 5.7%, biliary debris in 2.9%, hemobilia in 1.9%, and food impaction in 1.0%), and nonocclusion cholangitis (requiring biliary drainage) in 5.7%. Non-RBO AEs included post-endoscopic retrograde cholangiopancreatography pancreatitis in 11.7%, cholecystitis in 2.7%, and nonocclusion cholangitis in 2.7%. Stent removal was successful in 88.9% of attempts. The median time to RBO was 446 days. Conclusion: The placement of MHSEMS for MDBO was effective and feasible, demonstrating low migration rates, acceptable AEs, and removability.