A large cystic tumor with bile duct communication originating around the hepatic hilum.

Biliary cystic tumors are rare neoplasms occurring in the liver and less frequently in the extrahepatic biliary system. Recently, biliary cystic tumors in the liver are thought to be divided into a biliary mucinous cystic neoplasm and intraductal papillary neoplasm of the bile duct. We report a case of a large cystic tumor originating around the hepatic hilum which had luminal communication with the bile duct. A 74 year-old-woman underwent abdominal ultrasonography for a routine checkup. It revealed a large cystic tumor in the liver. CT scan and MRI showed a multilocular cystic tumor about 12 cm in diameter with a mural nodule occupying the medial and anterior segment of the liver. Intraoperative cholangiography showed a communication between the cystic tumor and the bile duct. Central bisegmentectomy of the liver and extrahepatic bile duct resection was performed. A papillary tumor existed in the common hepatic duct and was connected with the cystic tumor in the liver. The tumor was mostly composed of noninvasive papillary adenocarcinoma with adenoma components, and was associated with focal microinvasion of adenocarcinoma. Ovarian-like stroma was not observed. This lesion was diagnosed as a cystic variant of intraductal papillary neoplasm of the bile duct. The patient is alive with no recurrence for 18 months since the surgery.