Lumen apposing metal stents in drainage of pancreatic walled-off necrosis, are they any better than plastic stents? A systematic review and meta-analysis of studies published since the revised Atlanta classification of pancreatic fluid collections.

Lumen-apposing metal stents (LAMS) are increasingly being used in the drainage of pancreatic walled-off necrosis (WON). Best choice of stent is subject to argument, and studies are varied in the reported outcomes between LAMS and plastic stents (PS) to this end. We conducted a comprehensive search of multiple electronic databases and conference proceedings including PubMed, EMBASE, and Web of Science databases (earliest inception through July 2018) to identify studies that reported on the use of LAMS and PS in WON drainage. Studies published since the release of the revised Atlanta classification for pancreatic fluid collections (2014 to current) were included in the analysis. The outcomes were to estimate and compare the pooled rates of clinical success, and adverse-events. A total of 9 studies (737 patients) for LAMS and 6 studies (527 patients) for PS were included in the analysis. The pooled rate of clinical-success with LAMS was 88.5% (95% CI 82.5-92.6, I = 71.7) and with PS was 88.1% (95% CI 80.5-93.0, I = 78.1) and the difference was not statistically significant, P = 0.93. No difference was noted in the pooled rates of all adverse-events, LAMS: 11.2% (6.8-17.9, I = 82.0); vs PS: 15.9% (8.4-27.8, I = 78.8); P = 0.38. Based on our meta-analysis, LAMS and PS demonstrate equal clinical outcomes and equal adverse-events in the drainage of pancreatic WON.