International, multicenter retrospective trial comparing the efficacy and safety of bi-flanged versus lumen-apposing metal stents for endoscopic drainage of walled-off pancreatic necrosis

Background To compare fully covered bi-flanged metal stents (BFMS) and lumen-apposing metal stents (LAMS) for endoscopic ultrasound (EUS)-guided drainage/debridement of pancreatic walled-off necrosis (WON). Methods Patients with WON managed by EUS-guided therapy were divided into those who underwent: 1) drainage using BFMS; and 2) drainage using LAMS and scheduled direct endoscopic necrosectomy (DEN). Clinical success (resolution of the WON), technical success (successful stent placement), and adverse events (AEs) were evaluated. Results 387 patients underwent WON endoscopic drainage, 205 using BFMS and 182 using LAMS. The clinical success in the BFMS or LAMS groups were similar (197 [96.1%] vs. 174 [95.6%]; P=0.81). Median number of procedures required for WON resolution was significantly lower in BFMS compared to LAMS (2 vs. 3, P<0.001). Technical success for stent placement was similar in BFMS and LAMS groups (203 [99%] vs. 180 [99%], P=0.90). Procedure-related AEs were similar in the BFMS and LAMS groups (19 [9.3%] vs. 20 [10.9%], P=0.61). Stent dysfunction with occluding debris was higher in the BFMS group compared to LAMS group (21 [10.2 %] vs. 11 [5.9%], P=0.04). The migration rate was higher in the BFMS group than in the LAMS group (15 [7.3%] vs. 3 [1.6%]; P<0.001). DEN was required in 23 [11.2%] patients in the BFMS group after lack of WON resolution by conservative means. Conclusion BFMS with a "step-up approach" and LAMS with scheduled DEN are both safe and effective for EUS-guided drainage/debridement of WON.