Malignant melanoma of the biliary tract: a case report. A 58-year-old man was seen with obstructive jaundice and discomfort in the upper abdomen. Computed tomographic and ultrasound examinations revealed a soft-tissue mass in the gallbladder. Cholecystectomy and choledochotomy revealed a soft black mass in the gallbladder and a second one in the intrapancreatic portion of the common bile duct. Each was diagnosed as malignant melanoma. Subsequently, a Whipple resection of the pancreas, duodenum, and distal bile duct revealed a melanoma circumferentially invading and obstructing the distal common duct. No lymph node or distant metastasis was identified. Repetitive searches for another primary site have been negative. The tumor apparently originated in the biliary tract. The patient remains almost well 2 years after diagnosis. 