Patterns of care and outcomes of radiotherapy for lymph node positivity after radical prostatectomy.

OBJECTIVE: To evaluate the use and outcomes of adjuvant radiation therapy (ART) for men with lymph node (LN)-positive disease after radical prostatectomy (RP) using a population-based approach. PATIENTS AND METHODS: Surveillance, Epidemiology, and End Results (SEER)-Medicare linked data from 1995 to 2007 was used to identify 577 men with LN metastases discovered during RP and absence of distant metastases, of which 177 underwent ART ≤1 year of RP. Propensity score models were used to compare overall mortality and prostate cancer-specific mortality (PCSM) for men that did and those that did not receive ART.
RESULTS: Men in both groups received adjuvant androgen-deprivation therapy at similar rates after propensity weighting adjustments (33.6% vs 33.7%, P = 0.977). ART was not associated with differences in overall (5.09 vs 3.77 events per 100 person-years, P = 0.153) or PCSM (2.89 vs 1.31, P = 0.090) relative to men who did not receive ART.
CONCLUSIONS: ART after RP in men with LN-positive prostate cancer was not associated with improved overall or disease-specific survival, in contrast to previous single-centre studies. Prospective randomised studies are needed to assess the effectiveness of ART in this patient population.