Racial Variation in Patient-Reported Outcomes Following Treatment for Localized Prostate Cancer: Results from the CEASAR Study

Abstract

Background: Relatively little is known about the relationship between race/ethnicity and patient-reported outcomes after contemporary treatments for localized prostate cancer.

Objective: To test the hypothesis that treatment-related changes in urinary, bowel, sexual, and hormonal function vary by race/ethnicity.

Design, setting, and participants: The Comparative Effectiveness Analysis of Surgery and Radiation (CEASAR) study is a prospective, population-based, observational study that enrolled 3708 men diagnosed with localized prostate cancer in 2011-2012.

Outcome measurements and statistical analysis: Patient-reported disease-specific function was measured using the 26-item Expanded Prostate Index Composite (EPIC) at baseline and 6 and 12 mo after enrollment. Mean treatment differences in function were compared by race using risk-adjusted generalized estimating equations.

Results and limitations: While all race/ethnic groups reported considerable declines in scores for urinary incontinence after radical prostatectomy (RP) when compared to active surveillance, African-American men reported a greater difference than white men did (adjusted difference-in-differences 8.4 points, 95% confidence interval 2.0-14.8; p=0.01). No difference in bother scores was noted and the overall proportion of explained variation attributable to race/ethnicity was relatively small in comparison to primary treatment and baseline function. No clinically significant racial variation was noted for the sexual, bowel, irritative voiding, or hormone domains. Limitations include the lack of well-established thresholds for clinical significance using the EPIC instrument.

Conclusion: While these data demonstrate that incontinence at 1 yr after RP may be worse for African-American compared to white men, the difference appears to be modest overall. Treatment selection and baseline function explain a much greater proportion of the variation in function after treatment.

Patient summary: We observed that the effect of treatment for prostate cancer on patient-reported function did not vary dramatically by race/ethnicity. Compared to white men, African-American men experienced a somewhat more pronounced decline in urinary continence after radical prostatectomy, but the corresponding changes in bother scores were not significantly different between the two groups.

Keywords: Active surveillance; Comparative effectiveness; Patient-reported function; Prostate cancer; Radiation; Surgery.