Antiandrogen drugs lower serum prostate-specific antigen (PSA) levels in hirsute subjects: Evidence that serum PSA is a marker of androgen action in women

Assay by ultrasensitive methods of serum prostate-specific antigen (PSA) re cently demonstrated that many women have detectable levels of this molecule . Interestingly, serum PSA concentrations were higher in hirsute than in no nhirsute subjects, suggesting that, also in females, PSA may be regulated b y androgens. To establish the potential for this assay as a biochemical marker of androg en action in women, we studied 40 hirsute subjects recruited in a double-bl ind, placebo-controlled, B-month trial assessing the effects of 3 different antiandrogen drugs: spironolactone, flutamide, or finasteride. In each sub ject, serum PSA, free testosterone, and 3 alpha-androstanediol glucuronide were determined at baseline and at the end of treatments. At baseline, PSA concentrations were higher in these 40 women than in 19 no nhirsute healthy controls (12.9 +/- 1.5 vs. 4.9 +/- 0.7 pg/mL, P = 0.03) an d significantly correlated with serum free testosterone (r = 0.37, P < 0.00 5). After treatments, the 29 hirsute subjects given active drugs showed sig nificant reduction of serum PSA levels (7.2 +/- 1.4 vs. 14.7 +/- 3.0 pg/mL, P = 0.002). This phenomenon was correlated to baseline PSA values. No chan ge was found in the placebo group. In conclusion, serum PSA is increased in many hirsute women. A 6-month cour se of antiandrogen treatments with spironolactone, flutamide, or finasterid e determines a reduction of PSA levels in these subjects. These results sug gest that serum PSA is a biochemical marker of androgen action in tissues o f female subjects.