Fully-Covered Self-Expandable Metallic Stents Facilitate Effective Endoscopic Pancreatic Necrosectomy

Abstract

Background: Endoscopic necrosectomy of devitalized pancreatic tissue has been performed in selected patients with pancreatic necrosis. A limitation of endoscopic necrosectomy is not being able to remove sufficient necrotic retroperitoneal debris, which may be related to the size of the gastro-retroperitoneal (G-R) fistula. Prior reports have described the use of plastic pigtail stents to maintain the G-R track, necessitating subsequent dilation of the track before an endoscope can be passed. Using fully-covered self-expandable metallic stents (CSEMS) larger G-R tracks can be created and maintained. Methods: Patients with severe pancreatic necrosis that were referred to a tertiary-care center specialized in pancreatico-biliary disease were considered for endoscopic necrosectomy. Fluoroscopy and linear-EUS with color flow was used create a G-R fistula. After guidewire access and dilation of the G-R track, a CSEMS was deployed across the track. After maturation of the track, the CSEMS was removed and a therapeutic gastroscope was inserted into the retroperitoneum. Stone retrieval baskets, Roth nets, and cold snares were used to remove necrotic debris and devitalized pancreatic tissue. Results: Three male patients with severe pancreatic necrosis (ages 58, 60, 65) underwent endoscopic necrosectomy. Gallstones (n = 2) and a left-sided pancreatectomy for IPMN (n = 1) were the etiologies of necrotizing pancreatitis. The G-R track was stented with a Gore-Viabil CSEMS (10 × 60 mm or 10 × 100 mm) in two patients and with an Alimaxx-E CSEMS (22 × 70 mm) in one patient. CSEMS were left for a median of 45 days (range: 14-67 days) prior to stent removal and endoscopic necrosectomy. One patient with a 10 × 60 mm CSEMS had proximal stent migration into the stomach, requiring removal of the first stent and placement of a second 10 × 60 mm CSEMS 15 days later. That same patient also had significant bleeding from a pseudoaneurysm 34 days after deployment of the second CSEMS, which required embolization of the left GDA. All CSEMS were removed without complications. Follow-up CT imaging was available in two patients, which showed complete resolution of the necrotic retroperitoneal debris. Median duration of follow-up was 206 days (range: 14-232 days). In the patient with the 22 × 70 mm CSEMS, a 4-inch (10.0 × 3.5 × 2.0 cm), intact piece of devitalized pancreas was endoscopically removed from the retroperitoneum via the mouth without complications. Conclusions: The use of large-diameter CSEMS is effective in creating and maintaining G-R tracks for endoscopic pancreatic necrosectomy. CSEMS can be reliably removed and enable the debridement of large pieces of necrotic retroperitoneal tissue.