Transformation of fibrolamellar carcinoma to common hepatocellular carcinoma in the recurrent lesions of the rectum and the residual liver: a case report.

A 21-year-old man had undergone central bisegmentectomy of the liver due to fibrolamellar carcinoma (FLC). Twice, 24 and 30 months after the first operation, lymph node metastases were removed. We have reported this case previously and this is the second report of the same case. Forty-two months after the second operation to remove lymph node metastases, a recurrence occurred in the rectum and was excised. However, the tumor also recurred in the residual liver. The patient underwent hepatectomy for a palliative purpose but died 16 months after the last operation. Histopathologically, the primary tumor was diagnosed as pure FLC, but the lymph node metastases had foci of the common hepatocellular carcinoma (HCC) mixed with FLC. In contrast, the recurrent tumors in the rectum and the residual liver showed the histopathological features of common HCC. Thus, during repeated recurrences, histopathological features changed from pure FLC to common HCC.