[en] Purpose: Cooperative groups have investigated the outcome of androgen deprivation therapy combined with radiation therapy in prostate cancer pts with variable prerx prognostic indicators. This report describes an objective means of selecting pts for adjuvant hormonal therapy by examining bNED survival for groups of pts with specific prognostic indicators treated with adjuvant hormones (RT+H) vs matched controls treated with radiation therapy alone (RT). In addition, this report shows the 5-yr bNED survival for pts selected by this method for RT+H vs RT alone. Further, bNED survival is assessed multivariately according to treatment (RT+H vs RT) and predetermined prognostic treatment and prerx covariates. Materials and Methods: From (10(88)) to (12(94)), 684 T1-T3 NXM0 pts with known prerx PSA level were treated at Fox Chase Cancer Center. 568 of those pts were treated with RT alone while 116 were treated with RT+H. Table 1 lists the patient distributions for each of the putative prognostic factors indicative of bNED survival. We compare actuarial bNED survival rates according to treatment group within each of the prognostic groups. bNED survival is also compared for the two treatment groups using 107 RT+H pts and 107 matched (by stage, grade, and prerx PSA) controls randomly selected from the RT alone group. bNED survival for the 214 pts is then analyzed multivariately using stepwise Cox regression to determine independent predictors of outcome. Covariates considered for entry into the model included stage, grade, prerx PSA, treatment (RT vs RT+H), and center of prostate dose. bNED failure is defined as PSA ≥1.5 ngm/ml and rising on two consective determinations. The median follow-up is 30 mos (2 to 90 mos). Results: Table 1 presents three-year bNED actuarial survival rates according to treatment group for prerx PSA, gleason score, and stage groups. It is apparent that the T2C/T3, gleason 7-10, and the prerx PSA > 15 ngm/ml groups of pts benefit from hormonal therapy. Figure 1 presents a comparison of bNED survival according to treatment using the 214 matched case/controls and Kaplan-Meier methodology. It supports the finding that hormonal therapy translates to improved bNED survival (at 5 yrs, 55% vs 37%, p=.0001) although there is not survival advantage. Multivariate analysis demonstrates that hormonal treatment is the most significant independent predictor of bNED survival (p<.0001) along with prerx PSA (p=.0002) and palpation stage (p=.009), whereas grade and dose are not significant. Conclusions: 1) Pts with specific adverse prerx prognostic factors (i.e., T2C/T3, gleason score 7-10, prerx PSA > 15) benefit from adjuvant hormonal therapy. 2) Upon multivariate analysis, hormonal therapy is determined to be the most significant predictor of bNED survival, followed by prerx PSA and palpation stage. 3) The 5-yr bNED survival rates of 55% for RT+H vs 37% for RT alone clearly demonstrate that those pts do benefit from adjuvant hormone therapy. 4) The bNED survival curves are separated by about 20 mos, representing a delay in disease progression with adjuvant hormonal therapy