Introduction:
Endoscopic ultrasound (EUS)-guided transmural drainage is the standard minimally invasive treatment for symptomatic necrotizing pancreatitis. However, the optimal timing of direct endoscopic necrosectomy (DEN) following drainage remains uncertain. While the conventional step-up approach reserves DEN for patients with inadequate clinical response, immediate DEN may accelerate recovery by achieving earlier clearance of necrotic material.
Why was this study needed?:
The ideal timing of DEN after EUS-guided drainage has not been established.
The drainage-oriented step-up approach delays necrosectomy until clinically indicated.
Earlier necrotic tissue removal may shorten recovery without increasing complications.
Randomized evidence comparing immediate versus on-demand DEN has been lacking.
Results:
In the multicenter WONDER-01 randomized trial, immediate DEN significantly shortened the time to clinical success compared with the conventional drainage-oriented step-up strategy. Technical success was similarly high in both groups, and rates of procedure-related adverse events and mortality were comparable. However, all patients assigned to immediate DEN underwent necrosectomy, whereas fewer than half of those managed with the step-up approach ultimately required the procedure, highlighting that many patients can recover with drainage alone.
Clinical Impact:
Immediate DEN offers faster clinical resolution without compromising safety, making it an attractive option for patients in whom rapid recovery is desirable. However, because the step-up approach avoids unnecessary necrosectomy in a substantial proportion of patients, it remains an efficient and less invasive strategy. Treatment decisions should therefore be individualized based on disease severity, clinical response, and local expertise.
Bottom Line:
Immediate endoscopic necrosectomy after EUS-guided drainage accelerates recovery without increasing adverse events but results in more necrosectomy procedures, supporting individualized selection between immediate and step-up treatment strategies.