Predictors of mortality after prostate-specific antigen failure.

Abstract

We identified factors associated with the length of survival after prostate-specific antigen (PSA) failure. The study cohort comprised 81 of 206 men enrolled on a randomized trial evaluating external-beam radiation therapy (RT) with or without androgen suppression therapy (AST) and who experienced PSA failure. Salvage AST was administered at a PSA level of approximately 10 ng/mL as per protocol. Cox regression was used to determine factors associated with length of survival after PSA failure. A PSA DT (doubling time) <6 months (p = 0.04) and age at the time of PSA failure (p = 0.009) were significantly associated with length of survival. By 5 years, 35% and 65% of all-cause mortality was from prostate cancer in men whose age at PSA failure was 75 or higher vs. <75, respectively. Across all ages, 0%, 4%, as compared with 63% of men, were estimated to die of prostate cancer within 5 years after PSA failure if their PSA DT was >12, 6-12, or <6 months, respectively. Advanced age and a PSA DT <6 months at the time of PSA failure are associated with a significantly shorter survival.