Biological tissue markers in benign and malignant disease of the human prostate.

Immunoperoxidase techniques were used to study, the distribution of peanut agglutinin receptors, blood group isoantigens and several epithelial antigens in hyperplasia, adenosis, microcarcinoma and well differentiated adenocarcinoma of the prostate. Intraluminal and luminal surface PNA receptors were seen in all well differentiated carcinomas, 53% of microcarcinomas and 50% of adenosis, while no such sites could be demonstrated in benign hyperplasia. The expected blood group isoantigen was expressed in 75% of benign hyperplasias. When compared to the hyperplastic epithelium nearby, appropriate ABH expression was seen in 60% of adenosis, 47% of microcarcinomas and 25% of well differentiated carcinomas. A keratin antibody specifically labelling the basal cells in the normal prostate identified a subset of well differentiated carcinomas with preferential staining of the apical cytoplasm while microcarcinomas and adenosis were consistently negative. Our study establishes a highly ordered PNA receptor distribution in prostatic epithelia; it confirms early changes in the expression of ABH isoantigens in epithelial proliferative disorders of the prostate; it identifies a subset of keratin-positive well differentiated carcinomas, possibly of different ontogeny.