Association Between Radiation Therapy, Surgery, or Observation for Localized Prostate Cancer and Patient-Reported Outcomes After 3 Years.

Importance Understanding the adverse effects of contemporary approaches to localized prostate cancer treatment could inform shared decision making. Objective To compare functional outcomes and adverse effects associated with radical prostatectomy, external beam radiation therapy (EBRT), and active surveillance. Design, Setting, and Participants Prospective, population-based, cohort study involving 2550 men (≤80 years) diagnosed in 2011-2012 with clinical stage cT1-2, localized prostate cancer, with prostate-specific antigen levels less than 50 ng/mL, and enrolled within 6 months of diagnosis. Exposures Treatment with radical prostatectomy, EBRT, or active surveillance was ascertained within 1 year of diagnosis. Main Outcomes and Measures Patient-reported function on the 26-item Expanded Prostate Cancer Index Composite (EPIC) 36 months after enrollment. Higher domain scores (range, 0-100) indicate better function. Minimum clinically important difference was defined as 10 to 12 points for sexual function, 6 for urinary incontinence, 5 for urinary irritative symptoms, 5 for bowel function, and 4 for hormonal function. Results The cohort included 2550 men (mean age, 63.8 years; 74% white, 55% had intermediate- or high-risk disease), of whom 1523 (59.7%) underwent radical prostatectomy, 598 (23.5%) EBRT, and 429 (16.8%) active surveillance. Men in the EBRT group were older (mean age, 68.1 years vs 61.5 years, P < .001) and had worse baseline sexual function (mean score, 52.3 vs 65.2, P < .001) than men in the radical prostatectomy group. At 3 years, the adjusted mean sexual domain score for radical prostatectomy decreased more than for EBRT (mean difference, -11.9 points; 95% CI, -15.1 to -8.7). The decline in sexual domain scores between EBRT and active surveillance was not clinically significant (-4.3 points; 95% CI, -9.2 to 0.7). Radical prostatectomy was associated with worse urinary incontinence than EBRT (-18.0 points; 95% CI, -20.5 to -15.4) and active surveillance (-12.7 points; 95% CI, -16.0 to -9.3) but was associated with better urinary irritative symptoms than active surveillance (5.2 points; 95% CI, 3.2 to 7.2). No clinically significant differences for bowel or hormone function were noted beyond 12 months. No differences in health-related quality of life or disease-specific survival (3 deaths) were noted (99.7%-100%). Conclusions and Relevance In this cohort of men with localized prostate cancer, radical prostatectomy was associated with a greater decrease in sexual function and urinary incontinence than either EBRT or active surveillance after 3 years and was associated with fewer urinary irritative symptoms than active surveillance; however, no meaningful differences existed in either bowel or hormonal function beyond 12 months or in in other domains of health-related quality-of-life measures. These findings may facilitate counseling regarding the comparative harms of contemporary treatments for prostate cancer.