Distribution of Alpha-Fetoprotein and Immunoreactive Carcinoembryonic Antigen in Human Hepatocellular Carcinoma and Hepatoblastoma

The distribution of alpha-tetoprotein (AFP) and immunoreactivecarcinoembryonic antigen (CEA) in 62 hepatocellular carcinomas(HCC) and five hepatoblastomas (HBL) all surgically removedwas studied by an immuno-histochemical method, and the resultswere compared with the levels of the antigens in the patients'serum. AFP was present as coarse granules in the cytoplasm of immaturetumor cells. AFP-positive tumor cells were detected in 34/43cases (79.1%) with serum AFP levels higher than 400 ng/ml andin 1/24 (4.2%) of the remaining cases. They were present in8/32 (25%) cases of relatively well-differentiated HCC (Edmondson'sgrade I or II), 22/32 (68.8%) of relatively poorly differentiatedHCC (Edmondson's grade III or IV), and 5/5 of HBL. An antigen immunoreactive with a conventional rabbit anti-CEAim-munoglobulin (DAKO) but not with a murine monoclonal anti-CEAantibody (Hybritech) was present on the surface of bile canaliculiof both non-neo-plastic and neoplastic hepatocytes. This CEAcross-reactive differentiation antigen was more often foundin relatively well-differentiated tumors, and the presence ofthis antigen in tumors did not correlate with patients' serumCEA levels. In conclusion, CEA of an oncofetal nature was notproduced by either HCC or HBL.