Removal of a large stone growing around and encasing a plastic biliary stent: respect the ductal axis

Plastic biliary stents are commonly used during Endoscopic Retrograde Cholangio-Pancreatography (ERCP). The main indication for biliary stenting is benign or malignant obstruction. Plastic stents, among others, can be used as an escape route in patients with large common bile duct stones, or in cases of acute cholangitis with or without sphincterotomy to provide drainage until definitive treatment. Stent occlusion is the main disadvantage, limiting their patency to around 3 months, after which replacement is recommended. We present a case of a large, close to 2cm, stone developing around and encasing the proximal end of a plastic biliary stent. The stent/stone complex was successfully removed en bloc. The stent was placed in the common bile duct without sphincterotomy, and remained in situ for 2 years. The presented case highlights the importance of definitive treatment for common bile duct stones, the need to respect the ductal axis especially when dealing with large stones and the significance of biliary sphincterotomy during endoscopic interventions in the bile duct.