Alpha1-antitrypsin, protein marker in oral contraceptive-associated hepatic tumors.

Tissue specimens from a series of 46 hepatic tumors occurring in young female oral contraceptive users were tested for alpha1-antitrypsin deposition, utilizing immunocytochemical and histochemical methods. In two instances serum alpha1-antitrypsin phenotyping was also performed. Immunoreactive alpha1-antitrypsin deposits were demonstrated in benign lesions, including 56% of cases of focal nodular hyperplasia and 68% of cases of liver-cell adenoma, and in 89% of cases of malignant hepatoma. There was good correlation between alpha1-antitrypsin deposits and variable amounts of finely granular, or globular, diastase-resistant periodic acid-Schiff positivity within tumor cells. While quantitative differences in alpha1-antitrypsin deposits between benign and malignant cell proliferations were not observed, a qualitative continuum that linked all tumors in the study group was found. The findings suggest that alpha1-antitrypsin deficiency is not related to the hepatic tumors developing in oral contraceptive users. The tumor tissue deposits of alpha1-antitrypsin observed represent a marker protein, the significance of which is undefined.