HEPATOID CARCINOMA OF THE LUNG WITH PRODUCTION OF ALPHA-FETOPROTEIN AND ABNORMAL PROTHROMBIN - AN AUTOPSY CASE-REPORT

alpha-fetoprotein (AFP) is a useful tumor marker for the diagnosis of hepatic and testicular tumors. Several cases of AFP-producing lung can cer have been reported. We present here a patient with AFP-producing p rimary lung carcinoma, which showed high values of serum AFP (100,000 ng/mL), The concanavalin A nonbinding fraction rate of AFP was 15%. Gr oss and microscopic features of the lung carcinoma bore a striking res emblance to those of hepatocellular carcinoma. According to the histol ogic classification of lung tumor, this case was large cell carcinoma with prominent hepatoid differentiation. Immunohistochemically, we det ected AFP in the cytoplasm of the neoplastic cells. We also detected a nother useful tumor marker for the diagnosis of hepatocellular carcino ma, i.e., des-gamma-carboxy prothrombin (protein induced by vitamin K absence or the absence of antagonist-II [PIVKA-II]), in serum using an enzyme immunoassay and in tumor cells by immunohistochemical analysis .