Separate histogenesis of combined hepatocellular and cholangiocellular carcinoma in two patients.

Double primary liver carcinomas, i.e. hepatocellular carcinoma (HCC) and cholangiocellular carcinoma (CCC) are rare. Two patients in whom double primary liver carcinomas were surgically resected are described herein. Case 1: A 51-year-old Japanese man with chronic type B hepatitis underwent hepatectomy for primary HCC with intrahepatic metastasis. Case 2: A 67-year-old Japanese man with a history of rectal cancer and CCC underwent lateral hepatic segmentectomy for a suspected recurrence of intrahepatic CCC. Lack of direct contact between tumors, no evidence of histological transition and clearly different immunohistochemical staining for cytokeratin support a distinct histogenesis of the tumors in these two patients. The findings indicate that combined HCC and CCC can arise synchronously or metachronously as an intrahepatic double cancer.