Cell kinetic studies on prostatic intraepithelial neoplasia (PIN) and atypical adenomatous hyperplasia (AAH) of the prostate.

To investigate possible cell kinetic relations between benign prostatic hyperplasia (BPH), atypical adenomatous hyperplasia (AAH), prostatic intraepithelial neoplasia (PIN) and carcinoma, cell kinetic analyses were performed using radiolabelled DNA-precursors (3H-thymidine autoradiography), immunohistochemistry (proliferation marker Ki67/MIB1 and/or PCNA) and silver staining of nucleolar organizer regions (AgNOR). All methods yielded the lowest values for BPH and AAH, while maximal values were found in carcinoma of high malignancy. PIN was equal to GII-carcinomas, while AAH was between BPH and carcinoma of low malignancy. This investigation ranks BPH, AAH, low grade carcinoma, PIN and high grade carcinoma in order using different methods of cell kinetic analysis. The preneoplastic character of PIN is apparent whereas the character of AAH remains uncertain.