Demonstration of alpha 1-antitrypsin in hepatomas.

Sixty-nine primary malignant hepatomas were examined for the presence of alpha 1-antitrypsin (alph 1-AT) in tumor cells using immunohistochemical methods. Twenty-eight tumors showed positivity for alpha 1-AT. The reaction was globular and PAS-positive in 12 hepatocellular tumors and thus simulated the pattern of alpha 1-AT accumulation in hepatocytes in subjects carrying the Z-gene for alpha 1-AT. In fact, eight of these 12 tumors presented this pattern in the nontumours liver tissue. In ten hepatocellular tumors the reaction was finely granular throughout the hepatocytic cytoplasm, but was present in only a small number of cells. Still fewer cells were positive in six cholangiocarcinomas. The globular alpha 1-AT in tumor cells may be genetically determined when associated with the Z-gene. A reappearance of fetal gene products may be assumed in three hepatocarcinomas with globules positive for alpha-fetoprotein as well as alpha 1-AT.