Are self-expandable metal stents superior to plastic stents in palliating malignant distal biliary strictures? A meta-analysis and systematic review.

BACKGROUND: Palliation for inoperable malignant distal biliary strictures can be achieved with self-expandable metal stents (SEMS) and plastic stents (PS). This is a meta-analysis to compare PS and SEMS. The aim of the study is to compare clinical outcomes in patients with SEMS and PS.

METHODS: Study selection criteria were studied using SEMS and PS for palliation in patients with malignant distal biliary stricture. For data collection and extraction, articles were searched in Ovid journals, Medline, Cochrane database, and Pubmed. Pooled proportions were calculated using both Mantel-Haenszel method and DerSimonian Laird method for statistical analysis.

RESULTS: Initial search identified 1376 reference articles, of which 112 were selected and11 studies ( N  = 947) were included in this analysis. Pooled analysis showed SEMS patency to be 167.7days (95% CI = 159.2-176.3) compared to 73.3days (95% CI = 69.8-76.9) in PS. SEMS have lower odds of occlusion when compared to PS with an odds ratio of 0.48 (95% CI = 0.34-0.67). SEMS has a lower odds of cholangitis compared to SP, with an odds ratio of 0.46 (95% CI = 0.30-0.69).

CONCLUSION: SEMS seem to be superior to PS with better patency periods and survival duration. SEMS have lower occlusion rates, re-intervention rates, and cholangitis.