TESTOSTERONE, DIHYDROTESTOSTERONE AND ESTRADIOL LEVELS IN POSTMENOPAUSAL BREAST-CANCER TISSUES

The ability of breast tumours to synthesize hormones is well recognize d, and local production of sex steroids is thought to play a role in b reast cancer growth. We measured the intratumour and circulating level s of testosterone, dihydrotestosterone (DHT) and oestradiol in 35 hist ologically confirmed carcinomatous mammary tissues obtained at breast surgery from 34 postmenopausal patients, age 50-85 years. Intra-tissue steroids were extracted with ethanol:acetone (1:1; v/v), defatted wit h 70% methanol in water, and extracted with ether. Steroids, from tiss ue and serum, were separated by partition chromatography on celite col umns and were measured by RIA. Intratumour testosterone and DHT concen trations were significantly correlated, after the exclusion of an outl ier (r(s) = 0.71; P = 0.0001). No association was found between oestra diol and either of the two androgens. Mean oestradiol and DHT concentr ations were significantly higher in tissue than in blood (P = 0.0001). Mean testosterone levels in tissues did not significantly differ from those measured in blood. Our data suggest that at least a part of int ratissue DHT is produced locally from testosterone. The meaning of hig h oestradiol and DHT levels in cancer tissue still needs to be defined .