[The immunohistochemical localization of CA 15-3 in human breasts and their tumors]

The tissue distribution of CA 15-3, a breast carcinoma associated antigenic determinant, has been investigated by an avidin-biotin immunoperoxidase technique in the human breasts and in their tumors. In cases of scirrhous carcinoma, positive stainings for CA 15-3 were observed in almost all carcinoma cells. In cases of solid-tubular carcinomas and papillotubular carcinomas, the reaction was various and there was no correlation between the distribution of CA 15-3 and the clinical stage. Apical staining was recognized in both solid-tubular and papillotubular carcinomas, in benign breast tumors, and in normal breast tissues. CA 15-3 appears to be related to the degree of differentiation of the breast tissue.