S100 Can We Walk Away From Pancreatic Duct Stents? Assessing Frequency, Predictors, and Need for Endoscopic Removal

Introduction: Pancreatic duct (PD) stents are often placed with the intent of spontaneous passage or prolonged retention. We assessed the frequency and risk factors associated with spontaneous migration or inappropriate retention of PD stents after 4 weeks of endoscopic retrograde cholangiopancreatography (ERCP). Methods: Consecutive patients who underwent ERCP with PD stent placement at our tertiary care center from 2019 through 2024 were identified and categorized into those with retention or spontaneous migration at 4 weeks after ERCP. All patients were contacted to ensure compliance with follow-up imaging or procedures. PD stents without an internal flange were presumed to be placed with the intent of spontaneous passage. Spontaneous passage was defined by the absence of PD stent on imaging performed within 4 weeks. Inappropriate retention was defined by the presence of a non-flanged PD stent within the PD seen on imaging after 4 weeks of ERCP. Primary endpoint was PD stent retention 4 weeks after ERCP. Secondary endpoints included risk factors for retention and need for endoscopic removal of PD stents. Results: Of the 501 patients who met selection criteria, 482 patients underwent ERCP for biliary (289), pancreatic (181), or both biliary and pancreatic (12) indications. PD stents without internal flanges were used more frequently for biliary indications vs pancreatic indications (74.4% vs 31.5%, P < 0.001). Follow-up in 425 patients demonstrated that retention of PD stents occurred more frequently in the presence of internal flanges, ERCP performed for pancreatic disorders, and greater stent length and diameter. Post-ERCP adverse events were similar in both groups. Inappropriate retention of stents without an internal flange occurred in 29 (12.5%) patients, and only 5 (2%) required endoscopic removal. These 5 patients had a concomitant covered metal stent in the bile duct (n = 3), anomalous pancreas-biliary junction (1), or a transgastric jejunal feeding tube traversing the ampulla (1). Conclusion: The frequency of inappropriate retention of PD stents without internal flange is low, occurs due the mechanical obstruction at the ampulla, and requires endoscopic removal very rarely. A single, thin, short, PD stent without an internal flange has a minimal risk of inappropriate retention.