Inhibition of basal and adrenocorticotropin-stimulated plasma levels of adrenal androgens after treatment with an antiandrogen in castrated patients with prostatic cancer.
Ключови думи
Резюме
The basal plasma levels of cortisol, dehydroepiandrosterone (DHEA), DHEA sulfate (DHEA-S), and testosterone were studied in 20 patients with advanced prostatic cancer receiving combined treatment with an LHRH agonist and an antiandrogen [5,5-dimethyl-3-[4-nitro-3-(trifluoromethyl)-phenyl]-2 4-imidazolidinedione]. After 60 days of combined antihormonal therapy, plasma levels of testosterone decreased from 5.44 +/- 0.44 (SEM) to 0.136 +/- 0.052 ng/ml (2.5% of control). Somewhat unexpectedly, the plasma concentrations of the adrenal androgens DHEA and DHEA-S were reduced to 45 +/- 7 and 64 +/- 4% of control, respectively. The maximal reduction in plasma adrenal androgen levels occurred between 2 and 4 weeks of treatment. Whereas the increase in serum cortisol, 17-hydroxypregnenolone, and 17-hydroxyprogesterone concentrations 2 1/2 h after the injection of 0.25 mg human ACTH 1-24 was not affected by the combined treatment, the increment of DHEA and androstenedione after the same stimulus was reduced from 3.1 +/- 0.98 and 0.73 +/- 0.11 to 1.48 +/- 0.5 and 0.31 +/- 0.05 ng/ml, respectively. The reduced levels of serum DHEA and DHEA-S were not due to the LHRH agonist by itself, since similarly low levels of serum DHEA and DHEA-S were found in patients surgically castrated and receiving the same antiandrogen. These data suggest that treatment with an antiandrogen in castrated men inhibit the formation of adrenal androgens due to a blockade at the level of 17, 20-desmolase. The efficiency of the new combined antihormonal therapy (castration and antiandrogen) aimed at complete androgen neutralization in prostate cancer is thus further facilitated.