Heterotopic pancreas: a rare cause of bile duct dilatation--report of a case and review of the literature.

A case of a 77 year old woman with a heterotopic pancreas in the distal common bile duct is reported herein. The patient had no symptoms, but an ultrasound examination showed bile duct dilatation and subsequent endoscopic retrograde cholangiography demonstrated a spherical filling defect in the distal common bile duct. Under suspicion of a benign neoplasm in the common bile duct, resection of the common bile duct and hepaticojejunostomy using a Roux-en Y jejunal limb were successfully performed. Pathological examination revealed heterotopic pancreatic tissue in the distal common bile duct. This is only the ninth reported case of heterotopic pancreas occurring in the common bile duct or ampulla of Vater, and thus, a review of the literature is also given.