Introduction: Endoscopic ultrasound (EUS)-guided transmural drainage with on-demand endoscopic necrosectomy is increasingly utilized to manage walled-off necrosis (WON) but has been associated with substantial morbidity and mortality. Researchers at the Mayo Clinic developed a risk stratification system based on quadrant (an abdominal quadrant distribution), necrosis, and infection (Gastrointest Endosc. 2023;97:300-8) to predict clinical outcomes in this setting.
Methods: Among 357 patients with pancreatic fluid collections treated in a large multi-institutional WONDERFUL consortium between 2010 and 2020, we included 212 patients with available preprocedural computed tomography images. We compared treatment outcomes between the QNI groups 1 (≤2 quadrants and ≤30% necrosis, n = 79) and 2 (≥3 quadrants, 2 quadrants with ≥30% necrosis, or 1 quadrant with >60% necrosis and infection; n = 133).
Results: The two groups were comparable in all demographics except for preprocedural organ failure (20% vs. 2% for groups 2 and 1, respectively; P = 0.01). The rates of clinical treatment success did not differ significantly between the groups 2 and 1 (74% vs. 84%, respectively; P = 0.12). However, the time to clinical success was longer in group 2 compared to group 1 (median, 62 days vs. 36.5 days, respectively; P <0.01). Compared to group 1, group 2 was associated with higher rates of percutaneous interventions (16% vs. 3.8%, respectively; P <0.01), direct endoscopic necrosectomy (65% vs. 25%, respectively; P <0.01), mortality (12% vs. 3.8%, respectively; P = 0.03), and procedure-related adverse events (20% vs. 6.3%, respectively; P <0.01) but not with the risk of salvage surgery (7.5% vs. 5.1%, P = 0.48).
Conclusions: The newly developed QNI criteria well stratified the risk of adverse outcomes of patients receiving EUS-guided management of WON. A further investigation is warranted to elucidate the appropriate management strategy based on the QNI-based risk stratification.

Ichiro Yasuda

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