Endoscopic management of a large choledochocele associated with choledocholithiasis.

Choledochocele or type III choledochal cyst is a very rare lesion, defined as a cystic dilatation of the distal common bile duct protruding into the duodenal lumen. Abdominal pain, biliary disorders, and acute pancreatitis are frequently observed but malignant degeneration is rare. A 70-year-old man had a history of epigastralgia associated with abnormal liver function tests suggesting gallstones. During laparoscopic cholecystectomy, intraoperative cholangiography showed a 40-mm-diameter choledochocele associated with choledocholithiasis. A transcystic drain was placed after cholecystectomy had been completed. Endoscopic retrograde cholangiopancreatography confirmed the diagnosis and a 45-mm-long endoscopic sphincterotomy successfully treated both lesions as confirmed by a transcystic cholangiogram showing a thin-walled common bile duct with no residual stones. This case illustrates that the diagnosis of choledochocele remains difficult in clinical practice and confirms that endoscopic retrograde cholangiopancreatography is the best available diagnostic tool. Coexistent choledocholithiasis is observed in about 20% of choledochocele. Endoscopic sphincterotomy is feasible and effectively treats both lesions even in larger choledochoceles.