Predicting retention and rethinking removal of pancreatic duct stents with a standardized protocol: a United Statesbased retrospective study

Background/Aims: Pancreatic duct (PD) stent selection impacts migration and retention. We evaluated risk factors for migration versus inappropriate retention of PD stents at a high volume center using a standardized stent management protocol. Methods: Patients undergoing endoscopic retrograde cholangiopancreatography (ERCP) with PD stenting were retrospectively categorized by stent status at 2 weeks post-ERCP. Spontaneous migration was defined as absence of a PD stent on follow-up imaging, while inappropriate retention was defined as persistence of a non-flanged PD stent within the duct. The primary endpoint was PD stent retention at 2 weeks. Secondary endpoints included predictors of inappropriate retention and the need for endoscopic stent removal. Results: A total of 482 patients underwent ERCP for biliary (n=289), pancreatic (n=181), or dual (n=12) indications. Non-flanged PD stents for biliary vs. pancreatic indications were 74.4% vs. 31.5% (p<0.001). Among 425 patients with follow-up imaging, predictors of PD stent retention included internal flanges (odds ratio [OR], 6.39; 95% confidence interval [CI], 3.29-12.67), pancreatic indication (OR, 2.23; 95%CI, 1.22-4.07), and stent length >3cm (OR, 2.5; 95% CI, 1.23-5.07). Inappropriate retention of non-flanged stents occurred in 29 patients (12.5%), with only 5 (2.2%) requiring endoscopic removal due to mechanical obstruction. Conclusions: Inappropriate retention of short, narrow caliber, non flanged PD stents is infrequent and rarely requires endoscopic removal.