ABSTRACT: The use of advanced treatment technologies (ie, intensity-modulated radiotherapy [IMRT] and robotic prostatectomy) for prostate cancer is increasing. The extent to which these advanced treatment technologies have disseminated among patients at low risk of dying from prostate cancer is uncertain.To assess the use of advanced treatment technologies, compared with prior standards (ie, traditional external beam radiation treatment [EBRT] and open radical prostatectomy) and observation, among men with a low risk of dying from prostate cancer.Using Surveillance, Epidemiology, and End Results (SEER)-Medicare data, we identified a retrospective cohort of men diagnosed with prostate cancer between 2004 and 2009 who underwent IMRT (n = 23,633), EBRT (n = 3926), robotic prostatectomy (n = 5881), open radical prostatectomy (n = 6123), or observation (n = 16,384). Follow-up data were available through December 31, 2010.The use of advanced treatment technologies among men unlikely to die from prostate cancer, as assessed by low-risk disease (clinical stage ?T2a, biopsy Gleason score ?6, and prostate-specific antigen level ?10 ng/mL), high risk of noncancer mortality (based on the predicted probability of death within 10 years in the absence of a cancer diagnosis), or both.In our cohort, the use of advanced treatment technologies increased from 32% (95% CI, 30%-33%) to 44% (95% CI, 43%-46%) among men with low-risk disease (P < .001) and from 36% (95% CI, 35%-38%) to 57% (95% CI, 55%-59%) among men with high risk of noncancer mortality (P < .001). The use of these advanced treatment technologies among men with both low-risk disease and high risk of noncancer mortality increased from 25% (95% CI, 23%-28%) to 34% (95% CI, 31%-37%) (P < .001). Among all patients diagnosed in SEER, the use of advanced treatment technologies for men unlikely to die from prostate cancer increased from 13% (95% CI, 12%-14%), or 129.2 per 1000 patients diagnosed with prostate cancer, to 24% (95% CI, 24%-25%), or 244.2 per 1000 patients diagnosed with prostate cancer (P < .001).Among men diagnosed with prostate cancer between 2004 and 2009 who had low-risk disease, high risk of noncancer mortality, or both, the use of advanced treatment technologies has increased.