Patient Reported Comparative Effectiveness of Contemporary Intensity Modulated Radiation Therapy Versus External Beam Radiation Therapy of the Mid 1990s for Localized Prostate Cancer

Patient-Reported Outcomes Through 5 Years for Active Surveillance, Surgery, Brachytherapy, or External Beam Radiation With or Without Androgen Deprivation Therapy for Localized Prostate Cancer

Importance

Understanding adverse effects of contemporary treatment approaches for men with favorable-risk and unfavorable-risk localized prostate cancer could inform treatment selection.

Objective

To compare functional outcomes associated with prostate cancer treatments over 5 years after treatment.

Design, Setting, and Participants

Prospective, population-based cohort study of 1386 men with favorable-risk (clinical stage cT1 to cT2bN0M0, prostate-specific antigen [PSA] ≤20 ng/mL, and Grade Group 1-2) prostate cancer and 619 men with unfavorable-risk (clinical stage cT2cN0M0, PSA of 20-50 ng/mL, or Grade Group 3-5) prostate cancer diagnosed in 2011 through 2012, accrued from 5 Surveillance, Epidemiology and End Results Program sites and a US prostate cancer registry, with surveys through September 2017.

Exposures

Treatment with active surveillance (n = 363), nerve-sparing prostatectomy (n = 675), external beam radiation therapy (EBRT; n = 261), or low-dose-rate brachytherapy (n = 87) for men with favorable-risk disease and treatment with prostatectomy (n = 402) or EBRT with androgen deprivation therapy (n = 217) for men with unfavorable-risk disease.

Main Outcomes and Measures

Patient-reported function, based on the 26-item Expanded Prostate Index Composite (range, 0-100), 5 years after treatment. Regression models were adjusted for baseline function and patient and tumor characteristics. Minimum clinically important difference was 10 to 12 for sexual function, 6 to 9 for urinary incontinence, 5 to 7 for urinary irritative symptoms, and 4 to 6 for bowel and hormonal function.

Results

A total of 2005 men met inclusion criteria and completed the baseline and at least 1 postbaseline survey (median [interquartile range] age, 64 [59-70] years; 1529 of 1993 participants [77%] were non-Hispanic white). For men with favorable-risk prostate cancer, nerve-sparing prostatectomy was associated with worse urinary incontinence at 5 years (adjusted mean difference, -10.9 [95% CI, -14.2 to -7.6]) and sexual function at 3 years (adjusted mean difference, -15.2 [95% CI, -18.8 to -11.5]) compared with active surveillance. Low-dose-rate brachytherapy was associated with worse urinary irritative (adjusted mean difference, -7.0 [95% CI, -10.1 to -3.9]), sexual (adjusted mean difference, -10.1 [95% CI, -14.6 to -5.7]), and bowel (adjusted mean difference, -5.0 [95% CI, -7.6 to -2.4]) function at 1 year compared with active surveillance. EBRT was associated with urinary, sexual, and bowel function changes not clinically different from active surveillance at any time point through 5 years. For men with unfavorable-risk disease, EBRT with ADT was associated with lower hormonal function at 6 months (adjusted mean difference, -5.3 [95% CI, -8.2 to -2.4]) and bowel function at 1 year (adjusted mean difference, -4.1 [95% CI, -6.3 to -1.9]), but better sexual function at 5 years (adjusted mean difference, 12.5 [95% CI, 6.2-18.7]) and incontinence at each time point through 5 years (adjusted mean difference, 23.2 [95% CI, 17.7-28.7]), than prostatectomy.

Conclusions and Relevance

In this cohort of men with localized prostate cancer, most functional differences associated with contemporary management options attenuated by 5 years. However, men undergoing prostatectomy reported clinically meaningful worse incontinence through 5 years compared with all other options, and men undergoing prostatectomy for unfavorable-risk disease reported worse sexual function at 5 years compared with men who underwent EBRT with ADT.