Incidence, risk factors and endoscopic retrieval of proximally migrated pancreatic stents: 25 years of experience in a high-volume center - a case controlled study.

Background And Aim: Proximal migration is one of the complications after pancreatic stenting. This study aims to determine the incidence, risk factors and endoscopic treatment of proximally migrated pancreatic stents.

Methods: A retrospective search of all the endoscopic retrograde cholangiopancreatography (ERCP) records was conducted from 1997 to 2022 in our tertiary center. Proximal migration of the pancreatic stent was defined as when the stent shifted completely into the pancreatic duct and the distal end of the stent was no longer visible at the duodenal papilla.

Results: A total of 9017 pancreatic duct stentings of 6083 patients were performed. The proximal migration rate was 0.2% (17/9017). Three predictive factors for proximal migration were identified: pancreatic duct stones (OR, 0.107), residual pancreatic duct stones (OR, 8.290) and straight-shape stent (OR, 4.725). After including 19 patients transferred from other hospitals, 46 ERCPs were performed to retrieve the proximally migrated stents in 36 patients. The success rate of endoscopic removal was 80.6% (29/36). 1 (2.8%) patient was referred to surgery, and 6 patients had new pancreatic stents placed for conservative treatment. 21.7% (10/46) cases developed post-ERCP pancreatitis and 2.2% (1/46) developed infection.

Conclusions: Proximal migration of pancreatic stents is less common, but deserves more attention. Endoscopy is efficient in retrieving proximally migrated stents. In patients with residual pancreatic duct stones and straight stent, the risk of proximal migration is significantly increased.