Dihydrotestosterone measured in core biopsies from prostatic tissues

Dihydrotestosterone (DHT) levels were measured and related to the content of DNA in 10- to 15-mg tissue samples obtained by punch biopsies from the prostatic gland. The aim of the study was to provide an opportunity to detect the variation of dihydrotestosterone (DHT) in prostatic tissue on endocrine manipulations in phase III studies of metastatic prostatic cancer. DHT was assayed in ranges of 27.9 to 102.9 pg/ml or when related to DNA from 0.57 to 4.00 pg/micrograms DNA by modifying a commercial testosterone/dihydrotestosterone kit. Preliminary clinical results from nine patients with prostatic cancer and eight with benign hyperplasia showed a significantly lower DHT/DNA ratio in prostatic cancer. The predictive value of the histological grading was improved by estimates of the weighted mean nuclear volume. The trend that mean nuclear volume of prostatic cancer exceeded the mean nuclear volume of hyperplasia was clear, and a significantly larger nuclear variation was demonstrated in the malignant specimens. Neither the DHT/DNA ratio nor the mean nuclear volume appears to be sufficient to guide the handling of individual patients, but the described methods enable us by repeated measurements to follow the course of disease and response to treatment.