Mucin-producing carcinoma of the cystic duct that caused obstructive jaundice.

We report a very rare case of what appeared to be mucin-producing carcinoma of the cystic duct, and this is the forth case recorded in the English-language and Japanese literature. The patient was a 67-year-old man with a chief complaint of dark urine and jaundice. Cholangiography via an endoscopic nasobiliary drain showed dilatation of the common hepatic duct to 14 mm, with no visualization of the cystic duct or gallbladder, and an approximately 15-mm filling defect was observed at the junction of the common bile duct and the cystic duct.