Lumen apposing metal stents vs. double pigtail plastic stents for the drainage of pancreatic walled-off necrosis.

Background: Few studies compared lumen-apposing metal stents (LAMS) and standard double pigtail plastic stents (PS) for the endoscopic drainage of pancreatic walled-off necrosis (WON). Albeit sometimes large, previously described cohorts display considerable heterogeneity and often pooled together data from several centers, involving multiple operators and techniques. Moreover, they often lack a control group for the comparison of outcomes. The aim of this study was to compare clinical efficacy and safety of PS versus LAMS for the endoscopic drainage of infected WON.

Methods: Thirty patients were enrolled between 2011 and 2017. The present study is a single-center, 1:1 case-control study. We compared patients undergoing endoscopic drainages of infected WON through LAMS (cases) or PS (controls). The primary endpoint was the clinical efficacy (resolution of the WON/sepsis), the secondary endpoint was safety (procedure-related complications).

Results: Cases and controls were homogeneous in terms of etiology and clinical characteristics: 93% of cases and 86.7% of controls were clinically successfully treated, with no significant differences in rates of postoperative infections, bleedings, and stent migrations (respectively 13.3% vs. 21.4%; P=0.65; 13.3% vs. 0%; P=0.48; 13.3% vs. 7.1%; P=1.00). No difference was shown regarding the need for additional percutaneous or surgical treatments (33.3% vs. 13.3%; P=0.39). Cases, however, displayed a significantly prolonged mean hospital stay (90.2 days vs. 18.5 days; P<0.01) and a higher mean number of endoscopic procedures per patient (4.8 vs. 1.5; P<0.01).

Conclusions: PS might be not inferior to LAMS for the treatment WONs. Further prospective RCT is needed to compare clinical efficacy and safety in the two groups.