TREATMENT WITH FINASTERIDE FOLLOWING RADICAL PROSTATECTOMY FOR PROSTATE-CANCER

Objectives, The objective of this study was to evaluate the effect of finasteride (10 mg/d) or placebo on serum prostate-specific antigen (P SA) and recurrence rates in men with detectable PSA levels after radic al prostatectomy. Methods. A total of 120 men, 48 to 89 years old, pre viously treated with radical prostatectomy for prostate cancer within the past 10 years, with serum PSA levels between 0.6 and 10.0 ng/mL, w ith no evidence of skeletal metastasis on bone scan, and with no previ ous androgen deprivation therapy, were treated with 10 mg finasteride or placebo in a double-blind fashion for 12 months. After the first ye ar, all patients were treated with finasteride for an additional 12 mo nths. Primary endpoints were serum PSA levels and recurrence rates def ined as positive bone scan or positive biopsy. Results. Patients treat ed with finasteride had a delayed increase in serum PSA compared with placebo of approximately 9 months in the first year and 14 months by t he end of the second year. Patients with baseline PSA levels less then 1.0 ng/mL had no significant increase in serum PSA during the 2 years of treatment. Fewer recurrences were observed in the finasteride grou p, but these differences were not statistically significant. Finasteri de was well tolerated, and side effects were balanced between treatmen t groups. Conclusions. The results of this study indicate that treatme nt with finasteride delays but does not prevent the rise in serum PSA observed in untreated patients with detectable PSA levels after radica l prostatectomy. The reduction in local and distant recurrences in the finasteride group suggests that the effect on PSA reflects a direct e ffect on tumor growth without affecting the initial response to subseq uent hormonal therapy. These data require confirmation by studies that are longer and larger, focused on demonstrating significant differenc es in progression rates and survival before the use of finasteride can be considered as an option for men with detectable PSA levels after r adical prostatectomy.