Metal stents versus plastic stents for the management of pancreatic walled-off necrosis: a systematic review and meta-analysis

Background and aims: Endoscopic transluminal drainage of symptomatic walled-off necrosis (WON) is a good management option, although the optimal choice of drainage site stent is unclear. We performed a systematic review and meta-analysis to compare metal stents (MSs) and plastic stents (PSs) in terms of WON resolution, likelihood of resolution after 1 procedure, and adverse events.

Methods: An expert librarian queried several databases to identify studies that assessed WON management, and selection was according to a priori criteria. Publication bias, heterogeneity, and study quality were evaluated with the appropriate tools. We performed single and 2-arm meta-analyses for noncomparative and comparative studies using event rate random-effects model and odds ratio (OR)/difference in means, respectively.

Results: We included 41 studies involving 2213 patients. In 2-arm study meta-analysis, WON resolution was more likely with MSs compared with PSs (OR, 2.8; 95% confidence interval, 1.7-4.6; P < .001). Resolution with a single endoscopic procedure was similar between stents (47% vs 44%), although for those cases requiring more than 1 intervention, the MS group had fewer interventions, favored by a mean difference of -.9 procedures (95% CI, -1.283 to -.561). In single-arm study meta-analysis, when compared with PSs, MS use was associated with lower bleeding (5.6% vs 12.6%; P = .02), a trend toward lower perforation and stent occlusion (2.8% vs 4.3%, P = .2, and 9.5% vs 17.4%, P = .07), although with higher migration (8.1% vs 5.1%; P = .1).

Conclusion: Evidence suggests that MSs are superior for WON resolution, with fewer bleeding events, trend toward less occlusion and perforation rate, but increased migration rate compared with PSs.