From chronology to morphology: toward objective image-guided assessment of endoscopic ultrasound-guided drainage for walled-off necrosis

10.1055/a-2654-4317

Maruta et al. [1] recently challenged the long-standing 4-week safety interval before endoscopic ultrasound (EUS)-guided drainage of infected/symptomatic walled-off necrosis (WON). This time-based strategy had already been questioned by the POINTER trial [2], which showed no difference in safety (yet fewer interventions) for delayed versus early drainage.

In this evolving scenario, the WONDERFUL consortium proposed replacing this arbitrary threshold with an elegant image-based criterion (a discrete enhanced margin of ≥1 mm for ≥80% of the contour), demonstrating lower clinical success and safety when encapsulation was incomplete [1]. We strongly commend this major conceptual step toward morphology-driven decision-making in WON management. Future multicenter, ideally prospective, validations will be crucial in consolidating these insights and accounting for potentially relevant confounders. For instance, baseline complexity (e.g. co-morbidities, ascites, paracolic gutter extension, multiple WONs, presenting symptoms) and drainage modality (purely endoscopic vs. percutaneous adjuvancy) might influence the outcomes and deserve adjustment in larger cohorts.

Similarly, incorporating the Quadrant-Necrosis-Infection (QNI) classifier [3] as an additional level of stratification might also help in refining prognostic assessment beyond encapsulation, having recently been associated with an increased risk of step-up, longer hospital stay, and poorer prognosis [4], and even externally validated by the WONDERFUL consortium [5]

Standardized reporting of the interval between computed tomography scans and EUS drainage would also help capture the encapsulation dynamics, especially as a relevant proportion of the nonencapsulated cases in this study were drained beyond 4 weeks.

Finally, the reported 88% endoscopist–radiologist concordance is highly promising, yet the remaining variability raises a practical question: can encapsulation be confidently and consistently assessed by endoscopists at the point of care, or should radiologic validation remain mandatory?

In summary, we congratulate the authors on an elegant and timely study that aligns with the current move away from rigid temporal thresholds toward individualized, morphology-driven management of pancreatic necrosis. Their work sets a strong foundation for collaborative refinement of this approach.

Publication History

Article published online:
20 February 2026

• References

• 1 Maruta A, Iwashita T, Saito T. et al. Encapsulation levels rather than elapsed time after the onset of acute pancreatitis are related to clinical outcomes of pancreatic walled-off necrosis. Endoscopy 2025;
• 2 Boxhoorn L, van Dijk SM, van Grinsven J. et al. Immediate versus postponed intervention for infected necrotizing pancreatitis. NEJM 2021; 385: 1372-1381
• 3 Baroud S, Chandrasekhara V, Storm AC. et al. Novel classification system for walled-off necrosis: a step toward standardized nomenclature and risk-stratification framework. Gastrointest Endosc 2023; 97: 300-308
• 4 Vanella G, Leone R, Frigo F. et al. Predicting the need for step-up after EUS-guided drainage of peripancreatic fluid collections, including Quadrant-Necrosis-Infection score validation: a prospective cohort study. Gastrointest Endosc 2025; 102: 362-372.e8
• 5 Shiomi H, Saito T, Hamada T. et al. Quadrant, necrosis, and infection criteria for the risk stratification of walled-off necrosis: external validation using multi-institutional data. Gastrointest Endosc 2025; 102: 67-78.e3