Introduction: Mature peripancreatic fluid collection (MPFC) is a known and often challenging consequence of acute pancreatitis and often requires intervention. The most common method accepted is the "step-up approach," which consists of percutaneous drainage followed, if necessary, by minimally invasive retroperitoneal necrosectomy. Our paper aims to distinguish between plastic stents and lumen-apposing stents in the endoscopic management of MPFC in terms of morbidity, mortality, and haste of fluid collection resolution.

Methods: A retrospective analysis was performed at UMass Memorial Medical Center in patients with a diagnosis of MPFC. Utilizing medical records, clinical data, radiology, as well as endoscopic evidence, patients were differentiated by stent type used (plastic versus lumen-apposing) for the management of the MPFC. The primary outcome of the study was to assess the time to MPFC resolution following the placement of either plastic or lumen-apposing stents (on endoscopic ultrasound or computerized tomography scan) using a multivariate analysis with a logistic regression model.

Results: A total of 54 patients were included in this study from UMass Memorial Medical Center between 2012 and 2015. Twelve (22%) of these patients received lumen-apposing stents and 42 (78%) of these patients received plastic pigtail stents. For the lumen-apposing stent group, the mean interval between stent placement and resolution of MPFC was 57 days as compared to 102 days for plastic pigtail stents (p=0.02). The mean interval for placement/removal of lumen-apposing stents was 48 days as compared to 81 days for plastic pigtail stents (p=0.01). Stent migration was seen in 5 patients (11%) who received a plastic pigtail stent compared to 0 (0%) patients who received a lumen-apposing stent.

Discussion: Our study demonstrates that lumen-apposing stents result in a significant reduction in the interval between stent placement and MPFC resolution as well as the time from stent placement to removal, when compared to plastic pigtail stents, the prior standard-of-care. Our study reached similar conclusions regarding the number of stents placed. However, we did not find a significant difference between the complication rates, specifically peri- and postprocedural bleeding or perforation, between the 2 study groups, as demonstrated in prior papers.