Efficacy and safety of covered self-expandable metal stents for malignant hilar biliary obstruction: systematic review and meta-analysis.

Background And Aims: Covered self-expandable metal stents (CSEMSs) are used for malignant hilar biliary obstruction (MHBO) management. Despite increasing evidence, a comprehensive evaluation of the efficacy and safety of CSEMSs in MHBO management is lacking.

Methods: PubMed, EMBASE, and the Cochrane Library were screened up to March 31, 2024 for studies including MHBO treated by a CSEMS. Studies meeting predefined inclusion criteria, including adult MHBO patients treated with CSEMS placement, reporting technical success, clinical success, and adverse event rates were selected. Data synthesis and statistical analysis were performed using the random-effects model, with heterogeneity and publication bias assessment.

Results: From 401 articles, 7 studies were included. Pooled technical and clinical success rates of CSEMSs were 96.7% (95% confidence interval [CI], 92.6-98.6; I = 0%) and 91.6% (95% CI, 86.1-95.0; I = 0%). Overall adverse events were reported in 16.6% of cases (95% CI, 11.2-23.9; I = 24%), which included cholangitis (7.4%), pancreatitis (5.9%), liver abscess (5.9%), and cholecystitis (2.8%). Stent migration and recurrent biliary obstruction (RBO) were observed in 8.9% and 49.6% of cases, respectively, with a median time to RBO of 142 days. Reintervention was successful in 92.5% of cases (95% CI, 83.1-96.9; I = 0%).

Conclusions: Our meta-analysis revealed high technical and clinical success rates of CSEMS placement in MHBO. Adverse events, notably cholangitis, cholecystitis, and pancreatitis, were <10%. RBO and stent migration were mitigated by CSEMS removal and successful reintervention. Our findings highlight the efficacy and safety of CSEMSs in managing MHBO, warranting further research to optimize treatment strategies.