INFLUENCE OF FINASTERIDE ON FREE AND TOTAL SERUM PROSTATE SPECIFIC ANTIGEN LEVELS IN MEN WITH BENIGN PROSTATIC HYPERPLASIA

AbstractPurpose: Finasteride therapy for benign prostatic hyperplasia (BPH) results in a marked lowering of serum prostate specific antigen (PSA) levels. However, little is known about the effect of finasteride on unbound or free serum levels of PSA. Such information would be important since percent free PSA may substantially improve the cancer specificity of PSA testing. Thus, we prospectively studied the effect of finasteride therapy on total and free serum PSA levels.Materials and Methods: In a randomized, placebo controlled, double-blind trial 40 men with histologically confirmed BPH (age range 52 to 78 years) were treated with either 5 mg. finasteride daily (26 patients) for 9 months or placebo (14) for 6 months. Prostate volume was assessed by transrectal ultrasound. Serum levels of free and total PSA were measured from archived serum samples stored at −70C at baseline and for as long as 9 months of treatment.Results: In the finasteride group mean total PSA levels declined from 3.0 ng./ml. at baseli...