Abstract
BACKGROUND AND OBJECTIVES: EUS-guided drainage, and direct endoscopic necrosectomy (DEN) of walled-off necrosis (WON) using a lumen-apposing metal stent (LAMS) is safe and effective. Early debridement of WON may improve overall clinical outcomes. The aim of this study is to perform a multicenter retrospective study to compare the clinical outcomes and predictors of success for endoscopic drainage of WON with LAMS followed by immediate or delayed DEN performed at standard intervals. METHODS: Patients with WON managed by EUS-guided drainage with LAMS were divided into 2 groups: (1) those that underwent immediate DEN at the time of stent placement and (2) those that underwent delayed DEN 1 week after stent placement. DEN was subsequently performed every 1-2 week (s). Technical success (successful placement of LAMS), adverse events (AEs), and clinical success (complete resolution of the WON) were evaluated. RESULTS: Totally, 271 patients underwent WON drainage with LAMS: 69 who underwent immediate DEN and 202 who underwent delayed DEN. The technical success for LAMS placement was 100% in both groups. There was no significant difference in the overall procedural AEs between the immediate and delayed DEN groups (P = 7.2% vs. 9.4%; P = 0.81). Stent dislodgement during index endoscopy occurred in three patients in the immediate DEN group compared to zero in the delayed DEN group (P = 0.016); all three dislodgements occurred during necrosectomy. Clinical success for WON resolution in the immediate DEN group was 91.3% compared to 86.1% in the delayed DEN group (P = 0.3). The mean number of necrosectomy sessions for WON resolution was significantly lower in the immediate DEN group compared to the delayed DEN group (3.1 vs. 3.9, P < 0.001). Performing DEN at the time of stent placement was an independent predictor for resolution of WON with lesser number of DEN sessions (odds ratio 2.3; P = 0.004). CONCLUSIONS: DEN at the time of initial stent placement reduces the number of necrosectomy sessions required for successful clinical resolution of WON.