Metal versus plastic stents for malignant biliary obstruction: An update meta-analysis

Background and objective: The data on comparisons of stent patency, re-intervention rate and patient survival between metal and plastic stents in palliation of malignant biliary obstruction have never been pooled. We carry out a meta-analysis to summarise current evidence for clinical efficacy of metal and plastic stents in the treatment of malignant biliary obstruction. Methods: A comprehensive search of several databases was conducted. A fixed-effects or random-effects model was used to pool data of all study endpoints. Sensitivity analysis and subgroup analysis (distal vs. hilar biliary obstruction) were also performed. Results: Ten randomized clinical trials were identified. Compared with plastic stents, metal stents were associated with a significantly longer stent patency (HR = 0.36; 95% CI: 0.28-0.47; I2 = 0%), fewer numbers of re-intervention (WMD = 0.59; 95% CI: 0.28-0.90; I2 = 76.4%) and longer patient survival (HR = 0.74; 95% CI: 0.64-0.85; I2 = 16.0%). These results were still significant by sensitivity analysis. All outcomes reached statistical significance except of the pooled WMD of number of re-intervention in the studies with hilar biliary obstruction. No publication bias was observed. Conclusions: Metal stents were associated with a significantly longer stent patency, lower reintervention rate and longer patient survival in palliation of malignant biliary obstruction when compared to plastic stents. (C) 2012 Elsevier Masson SAS. All rights reserved.