Race is associated with discontinuation of active surveillance of low-risk prostate cancer: results from the Duke Prostate Center.

BACKGROUND

Active surveillance (AS) is increasingly utilized in low-risk prostate cancer (PC) patients. Although black race has traditionally been associated with adverse PC characteristics, its prognostic value for patients managed with AS is unclear.

METHODS

A retrospective review identified 145 patients managed with AS at the Duke Prostate Center from January 2005 to September 2011. Race was patient-reported and categorized as black, white or other. Inclusion criteria included PSA <10 ng ml(-1), Gleason sum ≤ 6, and ≤ 33% of cores with cancer on diagnostic biopsy. The primary outcome was discontinuation of AS for treatment due to PC progression. In men who proceeded to treatment after AS, the trigger for treatment, follow-up PSA and biopsy characteristics were analyzed. Time to treatment was analyzed with univariable and multivariable Cox proportional hazards models and also stratified by race.

RESULTS

In our AS cohort, 105 (72%) were white, 32 (22%) black and 8 (6%) another race. Median follow-up was 23.0 months, during which 23% percent of men proceeded to treatment. The demographic, clinical and follow-up characteristics did not differ by race. There was a trend toward more uninsured black men (15.6% black, 3.8% white, 0% other, P = 0.06). Black race was associated with treatment (hazard ratio (HR) 2.93, P = 0.01) as compared with white. When the analysis was adjusted for socioeconomic and clinical parameters at the time of PC diagnosis, black race remained the sole predictor of treatment (HR 3.08, P = 0.01). Among men undergoing treatment, the trigger was less often patient driven in black men (8 black, 33 white, 67% other, P = 0.05).

CONCLUSIONS

Black race was associated with discontinuation of AS for treatment. This relationship persisted when adjusted for socioeconomic and clinical parameters.