Necrosectomy and its timing in relation to clinical outcomes of EUS-guided treatment of walled-off pancreatic necrosis: a multicenter study

Background and Aims: EUS-guided transmural drainage with on-demand endoscopic necrosectomy (EN) is increasingly used to manage walled-off necrosis (WON). It has not been fully elucidated how EN and its timing are correlated with treatment outcomes compared with the drainage-based approach. Methods: Within a multi-institutional cohort of 423 patients with pancreatic fluid collections, including 227 patients with WON, 153 patients were identified who received the step-up treatment after the initial EUS-guided drainage of symptomatic WON; this included 102 EN patients and 51 non-EN (drainage) patients. Using the competing-risks multivariable proportional hazards regression model with adjustment for potential confounders, we calculated subdistribution hazard ratios (SHRs) for clinical treatment success (WON resolution) according to use of EN and its timing. Results: Compared with drainage alone, the EN-based treatment was associated with a shorter time to clinical success with a multivariable SHR of 1.66 (95% confidence interval, 1.12-2.46). Despite a higher risk of procedure-related bleeding in the EN group, there were no differences in the rates of severe adverse events (7.8% vs 5.9% in the EN and non-EN groups, respectively) or mortality (6.9% vs 9.8%). In the EN-treated patients, the timing of EN was not statistically significantly associated with the time to clinical success (P_trend = .34). Conclusions: Among patients receiving EUS-guided treatment of symptomatic WON, the use of EN in addition to drainage procedures was associated with earlier disease resolution. Further research is desired to determine the optimal timing of initiating EN considering a risk–benefit balance and cost-effectiveness.