Infected walled-off necrosis: upfront necrosectomy for some, optimized step-up for all

10.1055/a-2859-2294 The management of infected walled-off necrosis (WON) has evolved substantially over the past two decades. The shift from open surgical necrosectomy to minimally invasive step-up approaches represented a major advance, reducing procedure-related morbidity while preserving the principle of adequate source control [ 1 ]. Within this new perspective, endoscopic ultrasound (EUS)-guided drainage and direct endoscopic necrosectomy (DEN) have progressively moved to the forefront of treatment algorithms. Yet several questions remain unresolved, related to modality (plastic versus metal), timing (early versus delayed), and intensiveness of the endoscopic strategy. These technical debates can be boiled down to one simple question: should the most complete and aggressive strategy be used upfront to prevent deterioration, or reserved for patients who fail to improve after drainage? In the current issue of Endoscopy , the randomized trial by Ancil et al. [ 2 ] addresses this clinically relevant question in a selected population of patients with infected WON larger than 10 cm and containing more than 30% solid debris. Patients were allocated to either a top-down strategy, consisting of upfront DEN during the index drainage procedure followed by scheduled daily necrosectomy sessions until clearance, or a conventional endoscopic step-up strategy, in which DEN was reserved for predefined clinical non-response. “Should the most complete and aggressive strategy be used upfront to prevent deterioration, or reserved for patients who fail to improve after drainage?” The top-down group showed fewer reinterventions, fewer rehospitalizations, and shorter hospital stay, without any difference in adverse events or mortality. Previous studies, including the DESTIN and ACCELERATE trials [ 3 ] [ 4 ], have similarly suggested that earlier or accelerated necrosectomy may improve relevant clinical outcomes in patients with infected necrosis and higher disease burden. However, the interpretation of the primary outcome requires caution. In the top-down arm, the first DEN was considered part of the index procedure and was not counted as a reintervention, which structurally favors the top-down strategy. From a patient-centered and service-centered perspective, upfront DEN is not simply an extension of drainage. It requires stent dilation, scope exchange, longer procedure time, longer sedation exposure, and additional endoscopy resources. Feasibility is another key issue (a 15% rate of protocol deviations was registered in the top-down arm), as upfront DEN and scheduled necrosectomy every 24 hours demands uneventful index drainage and dedicated endoscopic expertise and infrastructure, and might involve nonendoscopic resources, such as sedation/anesthesia. Therefore, the lower number of “reinterventions” should not be interpreted as a lower overall treatment burden. Indeed, the total number of DEN sessions and procedures requiring sedation/anesthesia were similar between the two groups in the trial. A more clinically meaningful interpretation may therefore be that top-down necrosectomy shifts part of the treatment burden from an unplanned to a planned setting. This is not a minor achievement. Avoiding unplanned readmissions, recurrent fever, stent occlusion, and delayed source control is highly relevant for patients and healthcare systems; yet it is different from demonstrating that less treatment is required. The other side of the coin is that control groups across different trials consistently show that a tailored step-up approach spares additional procedures in a substantial proportion of patients, with approximately 30%–50% of patients responding to drainage alone (22% in the present trial). Shifting these patients to an unselected upfront necrosectomy strategy would inevitably expose some of them to overtreatment. The reduction in rehospitalizations is arguably the most compelling finding of the study. In patients with infected WON and abundant solid debris, early mechanical clearance may reduce the risk of persistent infection and stent occlusion. This provides a plausible explanation for the shorter hospital stay and fewer readmissions observed with the top-down strategy. At the same time, the difference in readmissions might be confounded by other variables. Particularly in collections with a high solid necrotic burden, maintaining drainage patency is a central component of treatment. As recent evidence suggests that double-pigtail plastic stents (DPPSs) placed coaxial to the lumen-apposing metal stent (LAMS) may reduce the risk of LAMS obstruction [ 5 ], their omission in this study (along with the use of a long-saddle LAMS) may have increased the vulnerability of the step-up arm to stent occlusion, the main cause of readmissions. In this regard, the observed differences may partly reflect the performance of this specific drainage strategy, rather than the intrinsic inferiority of a step-up approach. Rather than establishing top-down necrosectomy as a new default, this trial should be viewed as an opportunity to refine the timing of DEN according to patient risk. A universal strategy is unlikely to fit the heterogeneous spectrum of WON. In a more tailored strategy, early DEN would be considered for patients with higher disease burden, whereas a conservative step-up approach would remain appropriate for patients with a higher probability of spontaneous clinical improvement after drainage alone. Risk stratification tools may help refine this selection. Although no universally accepted prognostic model is currently available, the Quadrant–Necrosis–Infection (QNI) score is being repeatedly validated [ 6 ] [ 7 ] [ 8 ], while WON necrotic burden consistently emerges as a major determinant of treatment complexity and is therefore likely to remain central to future decision-making. Ancil et al. should be commended for challenging current practice and for providing prospective randomized data in a difficult-to-study population. Future evidence should focus on how to identify patients at higher risk of drainage failure, in whom upfront DEN may accelerate source control and reduce complications or readmissions. For the remaining patients, step-up should not mean passive observation after LAMS placement, but contemporary optimized drainage – likely incorporating LAMS protection with coaxial DPPSs – together with close reassessment, and timely escalation. Publication History Article published online: 13 July 2026 © 2026. Thieme. All rights reserved. Georg Thieme Verlag KG Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany Refers to: Top-down versus step-up approach after endoscopic ultrasound-guided drainage of infected walled-off necrosis: a randomized controlled trial Endoscopy eFirst DOI: 10.1055/a-2859-2294