[Immunohistochemical study of keratin-positive cells in human prostatic cancer]

The purpose of this study is to demonstrate the localization and distribution of keratin-positive cells (KPC) in the various pathological types of prostatic cancer, and to investigate the correlation between the basal cell and KPC. The localization of keratin was immunohistochemically investigated in 20 benign prostatic hyperplasia (BPH) and 33 human prostatic adenocarcinomas by the indirect immunoperoxidase technique, using anti human keratin rabbit serum on frozen sections. In BPH, strongly positive staining for keratin was detected in the cytoplasm of basal cells. Glandular epithelial cells were positive. In the cancer sections, no KPC was observed in all 6 cases of the large acinar type, all 10 cases of the small acinar type and all 12 cases of the column and cord type. On the other hand, KPC remained around the cancer cell populations in all 10 cases of the cribriform type. In the fused gland type, KPC was localized in 3 of 9 cases and in the medullary type 3 of 7 cases. If KPC was regarded as the marker of the basal cell as shown in BPH, it would be speculated that the absence of KPC occurred in some type of prostatic cancer showed the disappearance of basal cell. That is, KPC could not be detected in large acinar, small acinar and column and cord type, while KPC remained completely or partially in the cribriform, fused gland and medullary type. These histochemical alteration would suggest the different degree of malignancy in the various histological type of prostatic cancer.