PURPOSE: We determined if age is a prognostic factor of clinical outcomes, specifically overall survival, disease-free survival and progression-free survival in men with hormone refractory prostate cancer. MATERIALS AND METHODS: Data from 8 multi-institutional trials performed by Cancer and Leukemia Group B were combined. Eligible patients had progressive adenocarcinoma of the prostate after androgen ablation, Eastern Cooperative Oncology Group performance status 0 to 2, and adequate hematological, renal and hepatic function. The proportional hazards model stratified by study was used to assess the prognostic importance of age for predicting clinical outcomes. RESULTS: Of 1,194 men 132 (11%) were 50 to 60 years old and 120 (10%) were 80 to 89 years old. Median survival was 12.2 months (95% CI 10.6 to 13.8) in men 50 to 59 years old, 15.9 months (95% CI 14.2 to 17.6) in men 60 to 69 years old, 15.6 months (95% CI 13.8 to 16.9) in men 70 to 79 years old and 8.9 months (95% CI 6.6 to 12.1) in men 80 to 89 years old. Compared to 70 to 79-year-old men the HR for death in octogenarians was 1.3 (95% CI 1.0 to 1.6, p = 0.015). Furthermore, the HR for prostate cancer death in octogenarians was 1.3 (95% CI 1.1 to 1.7, p = 0.010) and in 50 to 59-year-old men it was 1.3 (95% CI 1.0 to 1.6, p = 0.042) compared to men 70 to 79 years old. Black men were at lower risk for death than white men (HR 0.77, 95 CI% 0.65 to 0.92, p = 0.004). CONCLUSIONS: Octogenarians and white men are at increased risk for death compared to other men with hormone refractory prostate cancer.