For most men with localized prostate cancer who defer surgery or radiation, primary androgen deprivation therapy offers no mortality benefit, Dr. Arnold L. Potosky reported.
Dr. Potosky of Georgetown University Medical Center, Washington, D.C., and colleagues looked at 15,170 men with newly diagnosed, clinically localized prostate cancer who did not receive curative therapy, including radiation, radical prostatectomy, or chemotherapy (J. Clin. Oncol. 2014 Mar. 17 [doi:10.1200/JCO.2013.54.2043]).
Overall, 23% of the cohort had primary androgen deprivation therapy (PADT) initiated within the first year of diagnosis. After adjustment for factors including age, baseline prostate-specific antigen, Gleason score, and T stage, the authors found that there was no difference between PADT-treated men and their PADT-naive counterparts in all-cause mortality (hazard ratio, 1.04; 95% confidence interval, 0.97-1.11) or prostate-cancer specific mortality (HR, 1.03; 95% CI, 0.89-1.19).
Indeed, despite its widespread use among patients who do not undergo curative-intent treatments, "the risk of serious adverse events and the high costs associated with its use mitigate any clinical or policy rationale for PADT use in these men," the authors wrote.
They did report a small but significant decreased risk of all-cause mortality (HR, 0.88; 95% CI, 0.78-0.97) in men with high-risk cancer (pretreatment PSA greater than 20; Gleason score, 8-10; clinical stage, T2c-T3a), but "the observed benefit was relatively small and should not be taken as definitive, given the limitations of our data," they noted.
An increased risk of death was reported in men with low-risk cancer (HR, 1.41; 95% CI, 0.99-1.82) and no difference in risk for men with intermediate-risk cancer (HR, 1.12; 95% CI, 0.92-1.32). There were no differences in risk of prostate cancer mortality by risk group category.
The authors disclosed no conflicts of interest related to this study. The study was supported by grants from the National Cancer Institute.