Background and Objectives: Endoscopic biliary plastic stenting is a safe and effective temporary therapeutic modality used in various benign biliary disorders. Long-term indwelling stents for more than one year without retrieval are termed “forgotten biliary stents”. In clinical practice, the forgotten stents are underestimated and the majority of data were obtained from case reports. The aim of this study was to determine the forgotten-biliary-plastic-stent-related complications, their management, and the patients’ clinical outcomes. Materials and Methods: This retrospective study was performed at three hospitals during the period from January 2021 to December 2023. In total, 577 patients with biliary plastic stents—inserted for a variety of benign biliary conditions—were included. They were divided into two groups, as follows: group 1 included 527 patients who had biliary stents removed within 3 months, and group 2 included 50 patients with biliary stents retrieved after one year of their deployment. The stent-related complications (e.g., acute cholangitis, stent clogging, distal stent migration, new common bile duct (CBD) stone formation, and proximal stent migration) and the endoscopic management success rate were evaluated. Results: Irretrievable CBD stones were the main indication for biliary plastic stenting in both groups. The stent-related complications, number of endoscopic sessions, and hospital admissions were significantly higher in the patients with forgotten biliary stents than those with stent removal within 3 months. All the study patients were successfully managed endoscopically with uneventful outcomes. Conclusions: Based on this retrospective study, non-adherence to the endoscopists’ instructions is the main reason for retained biliary stents for more than one year. The patients with forgotten stents had significantly higher complication rates, a higher number of endoscopic sessions, and a higher number of hospital admissions than those with stents that were retrieved in the scheduled time. All patients were managed endoscopically with a technical success rate of 100%, and with no complication-related mortality.
