Introduction
EUS-guided transmural drainage and subsequent interventions (e.g., endoscopic necrosectomy [EN]) are increasingly utilized for walled-off necrosis (WON). Few studies have examined the safety and effectiveness of EUS-guided treatment of WON according to the timing of subsequent EN.
Aims & Methods
We conducted a retrospective cohort study within the WONDERFUL (WON anD pERipancreatic FlUid coLlection) consortium, which consisted of expert endoscopists, gastroenterologists, interventional radiologists, and epidemiologists at eleven high-volume centers in Japan (UMIN CTR registration number, UMIN000044130). We included 222 patients who received EUS-guided transmural drainage for WON between January 2010 and November 2020. We excluded cases where no step-up treatment was required. We categorized the treatment strategies into early EN (< 14 days of the initial drainage), delayed EN (14-28 days), and drainage-oriented step-up approach (non-EN), and examined clinical outcomes (time to clinical success and adverse events [AEs]) by the timing of EN. Clinical success was defined as a reduction in the WON size to < 2 cm or the removal of all transmural stents and catheters along with the relief of the associated symptoms.
Results
Among the 222 patients, 63, 24, and 51 patients received early EN, delayed EN, and non-EN, respectively. The non-EN group was characterized by a higher rate of multi-locular collection (75% compared to 45% and 54% in the early and delayed EN groups, respectively; P = 0.005). The delayed EN group was characterized by a lower rate of WON extension to the pelvic cavity (8.3% compared to 32% and 35% in the early and non-EN groups, respectively; P = 0.045). Despite comparable overall rates of clinical success within 180 days between the groups, the conduct of EN was associated with early resolution of WON compared to non-EN with median times to clinical success of 62 days vs. 92 days, respectively (P = 0.043). No statistically significant difference was observed between the early and delayed EN groups (68 days vs. 55 days, P = 0.043). The number of endoscopic interventions was larger in the EN group than in the non-EN groups (median, 7 vs. 4.5 vs. 3 for early EN, delayed EN, and non-EN, respectively; P < 0.001). Early EN was associated with a higher rate of procedure-related AEs compared to delayed EN and non-EN (25.4% vs. 8.3% vs. 11.8%, respectively; P =0.070).
Conclusion
The EN-based step-up approach might be associated with a shorter time to clinical success in WON treatment compared to the drainage-oriented treatment. The treatment strategy for this population should be optimized based on further research on the optimal timing of EN initiation as well as the safety of EN.
References
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2) Baron TH, DiMaio CJ, Wang AY et al. American Gastroenterological Association Clinical Practice Update: Management of Pancreatic Necrosis. Gastroenterology 2020; 158: 67-75.e61
3) Isayama H, Nakai Y, Rerknimitr R et al. Asian consensus statements on endoscopic management of walled-off necrosis. Part 2: Endoscopic management. J Gastroenterol Hepatol 2016; 31: 1555-1565
4) Yasuda I, Nakashima M, Iwai T et al. Japanese multicenter experience of endoscopic necrosectomy for infected walled-off pancreatic necrosis: The JENIPaN study. Endoscopy 2013; 45: 627-634
Disclosure
Y.N. received research grants from Boston Scientific Japan, HOYA Corporation, and honoraria from Boston Scientific Japan, Fujifilm Corporation, Olympus Corporation. H.I. received research grants from Boston Scientific Japan, Fujifilm Corporation, Fujifilm Health Care Corporation, Gadelius Medical KK, Zeon Medical Inc., and honoraria from Boston Scientific Japan, Fujifilm Corporation, Taewoong Medical Devices, Olympus Corporation, Century Medical,Inc. and Cook Medical Japan G.K. Y.I. received honoraria from Gadelius Medical KK and Medicos Hirata.
