Histology and immunohistochemistry studies in prostate cancer

Histopathologic diagnosis of prostate carcinoma is not yet free of problems. There are particular difficulties in demarcating atypical forms of hyperplasia from well-differentiated carcinomas and in diagnosing and classifying incidental carcinomas. With the aid of conventional histology, however, nearly all diagnostic problems relevant for the patient can be solved. In routine diagnostics, modern immunohistochemical techniques are particularly helpful in assessing metastases of an undetected primary tumor. New immunohistochemical techniques provide insight into the receptor content of the prostate and show the histogenesis of prostate carcinoma in a new light. The estrogen receptor (modified ER-ICA test) is present in the nuclei of stromal cells and of basal cells within the glands, but not in the secretory epithelium. The receptor-associated protein--ER-D5--is found in the cytoplasm of stromal and basal cells. In basal cells and secretory epithelium, keratins show a different pattern. Immunohistochemically common adenocarcinomas display the pattern of secretory epithelium; urothelial and squamous cell carcinomas, on the contrary, display the pattern of basal cells. This finding does not support the opinion that the basal cell is the stem cell of secretory epithelium and the precursor cell of prostate carcinoma.