Testicular steroid secretion and peripheral serum steroid concentrations in patients with prostatic carcinoma after short-term estrogen treatment.

The short-term effects of the administration of estradiol on testicular steroid production were assessed by measuring the serum concentrations of testosterone, and a number of its precursors and metabolites, in the spermatic and peripheral veins of five inguinal hernia patients and one untreated prostatic carcinoma patient, as well as in 18 patients with advanced prostatic carcinoma, treated for 1 to 9 days with a single injection of 80 mg of polyestradiol phosphate (Estradurin). With the exception of progesterone, the treatment resulted in a significantly decreased testicular production of all steroids measured in spermatic vein serum; the same finding holds true for concentrations of testosterone, 5 alpha-dihydrotestosterone, and 17 alpha-hydroxyprogesterone in peripheral vein serum before and after treatment. By comparing the steroid concentrations in the spermatic and peripheral veins it is evident that the testicular production of all steroids measured persisted, although at a decreased level, even 7 to 9 days after Estradurin administration; this was most pronounced in the case of testosterone and 17 alpha-hydroxyprogesterone. It is apparent that the effect of estradiol on testicular steroid production is a gradual process which takes several days before it is clearly evident.