CHROMOSOME CHANGES IN BENIGN PROSTATIC HYPERPLASIA AND THEIR SIGNIFICANCE IN THE ORIGIN OF PROSTATIC-CARCINOMA

Cytogenetic studies of benign prostatic hyperplasia (BHP) are scarce. We analyzed primary cell cultures obtained from biopsies of prostatic tissues from 10 patients (mean age: 60.7 years) with histologic diagno sis of BHP to compare the eventual chromosome changes with those repor ted in prostatic adenocarcinoma. Clonal chromosome abnormalities were noted in five of the 10 cases, with loss of Y chromosome in all. In on e case, a clonal t(1;20) was observed with a -Y clone. Different numer ical and structural sporadic abnormalities were evident in eight. Chro mosome 1 was the chromosome most frequently involved in sporadic rearr angements. We concluded that -Y is a frequent nonrandom chromosome abn ormality in BHP in this sample of patients. Immunohistochemical studie s showed that loss of Y occurs in fibroblasts and not in epithelial ce lls; therefore, this anomaly is not related to cancer development.