Hepatoid tumors (HTs) are rare extra-hepatic neoplasms with the histological features, biochemical profile and, sometimes, even clinical course of hepatocellular carcinoma. We present a case of rectal hepatoid adenocarcinoma with metachronous liver metastases.
Four months after total procto-colectomy for a rectal adenocarcinoma (Astler-Coller C2), a 42-year-old man with ulcerative colitis showed hypoechoic masses in the hepatic parenchyma by abdominal ultrasonography. Carcinoembryonic antigen was normal, but alpha-fetoprotein was 32,000 microg/L. Fine-needle biopsy revealed that liver masses were positive for hepatocellular carcinoma. The patient underwent left hepatectomy and alcoholisation of a small deep nodule in segment 8.
Immunohistochemistry and albumin mRNA in situ hybridization suggested that the nodules were metastases of a HT. The patient was well during the first 6 months and refused any adjuvant chemotherapy. He died from liver failure 19 months after initial diagnosis.
HT is a rare colon cancer. The preoperative diagnosis of this tumor requires a high degree of suspicion, the availability of a panel of immunohistochemical markers, and a certain amount of luck. The prognosis is poor despite an aggressive and multimodal therapeutic strategy. So far, none of the hypotheses proposed about the origin and the biology of these tumors is convincing.