Immediate or on-demand endoscopic necrosectomy for necrotizing pancreatitis
Saito T et al, Gastroenterology. 2026;171(1):140-153
The randomized Wonder-01 trial demonstrated that immediate necrosectomy following EUS-guided drainage of walled-off necrosis reduced time to clinical success without increasing adverse outcomes, but required more endoscopic procedures as compared to on-demand necrosectomy.
Background and aims: The optimal timing for direct endoscopic necrosectomy (DEN) after endoscopic ultrasound (EUS)-guided transmural drainage of symptomatic necrotizing pancreatitis remains unknown. We hypothesized that immediate DEN after EUS-guided drainage might reduce the time to disease resolution compared with a drainage-oriented step-up approach.
Methods: This study was a multicenter, open-label, superiority randomized trial (WONDER-01). Among patients who received EUS-guided treatment for symptomatic necrotizing pancreatitis, eligible patients were randomly assigned 1:1 to receive either immediate DEN or the drainage-oriented step-up approach. The primary endpoint was the time from randomization to clinical success, defined as a decrease in collection size to ≤3 cm and an improvement in inflammatory markers.
Results: Seventy patients were enrolled in this study: 33 in the immediate DEN arm and 37 in the step-up arm. Immediate DEN was associated with a shorter time to clinical success than the step-up approach (p = 0.009), with median times (95% confidence interval) of 29 (19-34) and 44 (38-52) days, respectively. All patients in the immediate DEN arm received DEN compared with 46% in the step-up approach arm, but the rates of procedure-related adverse events were comparable (24% vs. 22%, respectively; p = 0.79). No significant differences were noted between the treatment arms in terms of technical success (100% vs. 97%; p > 0.99) and mortality (12% vs. 5.4%; p = 0.41).
Conclusions: Compared with the step-up approach, immediate DEN after EUS-guided drainage of necrotizing pancreatitis reduced time to clinical success without increasing adverse outcomes but required more DEN procedures.