Su1072 Comparison of Complications for Covered Versus Uncovered Metal Stents in Malignant Biliary Strictures: A Meta-Analysis and Systematic Review

Abstract

Background: Self expandable metal stents (SEMS) are used for palliating inoperablemalignant biliary strictures. The difference in complication rates between covered and uncovered metal stents in these patients is unclear. There have been recent retrospective studies and randomized controlled trials that evaluated the clinical efficacy of covered and uncovered stents. This is a meta-analysis comparing the complications with covered versus uncovered stents in these patients Aim: Compare complications in patients with malignant biliary strictures managed with covered metal stents versus uncovered metal stents.Method: Study Selection Criteria: Studies using covered and uncovered metal stents for palliation in patients with malignant biliary stricture / obstruction were selected. Data collection & extraction: Articles were searched in Medline, Pubmed, Ovid journals, CINAH, International pharmaceutical abstracts, old Medline, Medline nonindexed citations, and Cochrane Central Register of Controlled Trials & Database of Systematic Reviews. Two reviewers independently searched and extracted data. Any differences were resolved by mutual agreement. Statistical Method: Pooled proportions were calculated using both Mantel-Haenszel method (fixed effects model) and DerSimonian Laird method (random effects model). The heterogeneity among studies was tested using Cochran's Q test based upon inverse variance weights. Results: Initial search identified 1436 reference articles, of which 122 were selected and reviewed. 13 studies (N=2159) for covered and uncovered metal stents which met the inclusion criteria were included in this analysis. Pooled odds ratio for migration of covered versus uncovered stents was 9.9 (95% CI = 4.5 to 22.3). Odds ratio for stent occlusion in covered versus uncovered stents was 0.79 (95% CI = 0.65to 0.96). Pooled data for all the complications is shown in table 1. The pooled effects estimated by fixed and random effect models were similar. The p for chi-squared heterogeneity for all the pooled accuracy estimates was > 0.10. Conclusions: Covered metal stent seems to have higher odds of migration and lower odds of occlusion when compared to uncovered metal stent in patients with malignant biliary strictures. Although there were slight differences in occurrence of pancreatitis, cholangitis and cholecystitis in both the groups, the results were not statistically significant. Table 1