Elevated free cortisol plasma levels in patients with prostatic carcinoma undergoing treatment with estrogens

The total cortisol concentration (TCC), the percentage of free cortisol (%FC) and the apparent free plasma cortisol concentration (AFCC) have been determined in plasma samples of 9 patients affected by prostatic carcinoma undergoing treatment with estrogens measured by an equilibrium dialysis system and a radioimmunological method. The values found in this group of patients were compared to those obtained in 9 untreated control patients and in normal healthy persons. The mean TCC values found in treated patients were significantly higher than in the controls, both in basal condition (circadian rhythm) and after dynamic tests, while the mean %FC values were significantly lower than the controls except for the results obtained after an ACTH stimulation test. The mean AFCC values in treated patients were elevated both in basal condition and after the dexamethasone suppression test (DST), but the difference between the two groups of patients was statistically significant only after DST. This study demonstrates that patients with prostatic carcinoma undergoing treatment with estrogens can have markedly increased free plasma cortisol levels with an impairment of the hypothalamus-pituitary-adrenal axis.