Timing of Androgen Deprivation Therapy and its Impact on Survival After Radical Prostatectomy: A Matched Cohort Study

Purpose: We assessed the impact of the timing of androgen deprivation on disease progression after radical prostatectomy for patients with localized prostate cancer. Materials and Methods: We evaluated all patients who underwent radical prostatectomy between 1990 and 1999. Patients with pathological lymph node negative disease who received androgen deprivation therapy were then separated into 5 groups for analysis based on the time of hormone therapy initiation: 1-adjuvant androgen deprivation, 2-androgen deprivation therapy started at a postoperative prostate specific antigen of 0.4 ng/ml or greater, 3-at prostate specific antigen 1.0 or greater, 4-at prostate specific antigen 2.0 or greater and 5-at systemic progression. The first 4 groups were matched by clinical and pathological features to control groups who did not receive androgen deprivation after surgery using a nested, matched cohort design. Median followup for the entire cohort was 10 years. Clinical end points included systemic progression-free survival and cancer specific survival. Results: After matching clinicopathological variables adjuvant androgen deprivation therapy was associated with improved 10-year systemic progression-free survival (95% vs 90%, p <0.001) and 10-year cancer specific survival (98% vs 95%, p = 0.009), although overall survival for these patients remained unchanged (84% vs 83%, p = 0.427). In contrast, we found that men who started hormonal therapy at a postoperative prostate specific antigen of 0.4 or greater, 1.0 or 2.0 did not have improved systemic progression-free or cancer specific survival. Conclusions: Adjuvant hormonal therapy modestly improves cancer specific survival and systemic progression-free survival after prostatectomy. The benefit of hormone therapy is lost when androgen deprivation is delivered at the time of prostate specific antigen recurrence or systemic progression.