A Case of Intrahepatic Mucinous Cholangiocarcinoma

Abstract

Background: Mucinous carcinoma of the liver is a rare variant of intrahepatic cholangiocarcinoma. Herein, we report a resected case of mucinous carcinoma of the liver with a literature review. Case presentation: A 78-year-old woman was admitted to our hospital because of a large hepatic tumor, which had been revealed during tests for liver dysfunction. CT examination revealed that the large cystic tumor, 15 cm in a diameter, was located in the left hepatic lobe. Enhanced MRI was unable to visualize any nodules on the cyst wall. PET-CT partially detected FDG accumulation at the tumor margin. Extended left lobectomy was performed under a preoperative diagnosis of hepatobiliary cystadenocarcinoma. The extrahepatic bile duct was preserved because an intraoperative fast frozen section showed that the cut margin of the bile duct was cancer-negative. Pathological examination showed that the tumor cells had proliferated in the form of vesicles, and contained a large amount of mucus in the cytoplasm. Immunostaining demonstrated positivity for CK7 and CK19, and negativity for CK20, Hepatocyte, glypican 3, and CDX2. Finally, the hepatic tumor was diagnosed as intrahepatic mucinous cholangiocarcinoma. Conclusion: This case was an extremely rare variant of intrahepatic cholangiocarcinoma.