Relationship of testosterone, sex hormone binding globulin, and calculated free testosterone to subsequent clinical progress in patients with carcinoma of the prostate treated with bilateral orchidectomy or estrogens.

The concentration in serum of testosterone, sex hormone binding globulin (SHBG), and albumin has been measured, and from these measurements free testosterone has been calculated in 75 patients with carcinoma of the prostate treated with either bilateral orchidectomy, stilbestrol, or estramustine phosphate (Estracyt). After exclusion of 3 noncompliant patients, total testosterone did not differ significantly between treatments, but free testosterone was lower in estrogen-treated patients (5.9 +/- 0.9 (SEM) pmol/l, n = 28) compared with the orchidectomized patients (23 +/- 1.4 pmol/l, n = 44) (P less than 0.001); all of the estrogen-treated patients falling in the lower third of the range of the orchidectomized patients. Free testosterone did not change systematically during several years of treatment and there was no evidence of a rise with clinical deterioration. In the 33 patients with metastatic cancer treated with orchidectomy, the third with the lowest free testosterone or total testosterone showed a better survival over 2 years than the two-thirds with higher free or total testosterone; thereafter, the advantage was lost.