Purpose
To determine the clinical and sociodemographic predictors of beginning an active treatment among an ethnically diverse population of men with low-risk prostate cancer initially on observational management.
Materials and Methods
We retrospectively studied men diagnosed with low-risk prostate cancer between 2004 and 2012 at Kaiser Permanente Northern California, who did not receive any treatment within the first year of diagnosis and had at least two years of follow-up. We used Cox proportional hazards regression models to determine factors associated with time from diagnosis until active treatment.
Results
We identified 2,228 eligible men who were initially on observation, and 27% began an active treatment during follow-up (median 2.9 years). Non-Hispanic Black men were marginally more likely to begin an active treatment (hazard ratio [HR] 1.3, 95% CI 1.0–1.7) than non-Hispanic White men, independent of baseline and follow-up clinical measures. Among men who remained on observation, non-Hispanic Black men were re-biopsied within 24 months of diagnosis at slightly lower rates than non-Hispanic White men (HR 0.70, 95% CI 0.6–1.0). Gleason grade progression (HR 3.3, 95% CI 2.7–4.1) and a PSA doubling time < 48 months (HR 2.9, 95% CI 2.3–3. 7) were associated with initiation of active treatment, independent of race.
Conclusions
Sociodemographic factors, such as ethnicity and education, may independently influence a patient's decision to pursue active treatment and their utilization of serial biopsies during active surveillance. These factors are important in further studies of prostate cancer treatment decision making.