Abstract
BACKGROUND: Endoscopic placement of fully covered self-expanding metal stents (FCSEMS) is a treatment for distal biliary strictures (DBS). However, there remains a notable gap in the research regarding the efficacy and safety of FCSEMS in benign distal biliary stricture (BDBS) and malignant distal biliary stricture (MDBS). OBJECTIVE: To compare the short-term efficacy and long-term safety of FCSEMS in benign versus malignant DBS. DESIGN: A retrospective, single-center cohort study. METHODS: We conducted a retrospective analysis of 123 patients with DBS who underwent FCSEMS placement via endoscopic retrograde cholangiopancreatography (ERCP) at Shanghai East Hospital Affiliated to Tongji University from January 2019 to December 2024. Patients were stratified into BDBS (n = 46) and MDBS (n = 77) based on comprehensive diagnostic criteria, including medical history (underlying diseases, prior surgeries, etc.), clinical manifestations, laboratory tests (hepatic function panel, tumor biomarkers, IgG4, autoimmune antibodies, etc.), and multimodality imaging (Computed Tomography, magnetic resonance cholangiopancreatography, endoscopic ultrasound, etc.). The primary endpoint was short-term stricture resolution rate; secondary endpoints included ERCP-related complication rates (short- and long-term). RESULTS: Median follow-up durations were comparable between BDBS (6 (4,9) months) and MDBS (7 (4,12) months) groups (p > 0.05). Short-term stricture resolution rates were 97.8% (45/46) in the BDBS group and 92.2% (71/77) in the MDBS group (p > 0.05). Early ERCP complications (hyperamylasemia, bleeding, perforation, cholecystitis) did not differ significantly between groups (all p > 0.05). However, the incidence of post-ERCP pancreatitis (PEP) was markedly higher in BDBS (37.0%, 17/46) than in MDBS (7.8%, 6/77; p < 0.05). Long-term complications (stent migration, occlusion) showed no intergroup differences (all p > 0.05), but late biliary infections were more frequent in MDBS (41.7%, 10/24) versus BDBS (7.7%, 3/39; p < 0.05). CONCLUSION: FCSEMS effectively alleviates strictures in both benign and malignant DBS, with comparable short-term efficacy. Notably, BDBS patients had a higher risk of early PEP, whereas MDBS patients were more prone to late biliary infections. Long-term stricture resolution was not analyzed due to divergent disease trajectories (e.g., limited survival in MDBS).