Sarcomatoid Intrahepatic Cholangiocarcinoma: A Rare Case of Primary Liver Cancer

ABSTRACT

Sarcomatoid carcinoma arising from intrahepatic cholangiocyte, an extremely rare primary liver cancer, has highly invasive and metastatic potential. The pathogenesis of this tumor is unclear, although histogenetic mechanisms, such as transdifferentiation/dedifferentiation (epithelial-mesenchymal transition or metaplastic transformation), biphasic differentiation (combination and collision), and redifferentiation, might be suggested to explain the simultaneous co-existence of carcinoma and sarcoma components in the same tumor. Immunohistochemical staining might be necessary to differentiate whether sarcomatous component is originated from hepatocyte or cholangiocyte. We report a case of sarcomatoid intrahepatic cholangiocarcinoma in a 58 year-old man presenting as an incidentally detected liver mass on regular health examination, which was diagnosed by an application of immunohistochemical methods after surgical resection, with a review of the literature based on 9 cases reported in Korea.