Race, treatment, and long-term survival from prostate cancer in an equal-access medical care delivery system.
OBJECTIVE
To evaluate long-term survival of black and white prostate cancer patients in an equal-access medical care system to help distinguish biological from medical and social explanations of mortality differences.


METHODS
Retrospective study of US Department of Defense tumor registry patients with prostate cancer. Ethnicity, age, diagnosis, staging, risk factors, treatment, and survival end points were extracted.


METHODS
Prostate cancer patients (N = 1606; 7.5% black, 92.5% white) who were active-duty personnel, dependents, or retirees eligible for care in the military medical system.


METHODS
Racial differences in tumor stage and grade, risk factors, recurrence, and treatment wait time (time between initial diagnosis and initial treatment); influence of stage, grade, treatment, wait time, age, and race on survival.


RESULTS
No differences were found in behavioral risk factors or tumor grade or size, but blacks entered active treatment (P < .001) and exhibited a higher relative risk of cancer (P = .01) in younger age groups, presented with higher stage (P < .001), and demonstrated increased progression in distant metastatic disease (P = .01). No significant differences were detected in overall wait time. When adjusted for stage, no difference was found in type of treatment. Overall, stage, grade, and age were found to affect survival (P = .04 to P < .001), but race did not. When analyzed by stage, blacks demonstrated a clear trend of longer survival for distant metastatic disease (P = .04 to P = .06). This trend was confirmed using Kaplan-Meier estimates (P = .04, likelihood ratio).


CONCLUSIONS
This analysis suggests that in an equal-access medical care system there are no stage-specific differences in treatment between black and white prostate cancer patients. Survival among blacks is similar to that among whites and may surpass it for high-stage disease.
D000328:Adult; D000367:Age Factors; D000368:Aged; D044383:Black People; D006297:Health Services Accessibility; D006772:Hospitals, Military; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009367:Neoplasm Staging; D011471:Prostatic Neoplasms / Q000208:ethnology / Q000401:mortality* / Q000473:pathology / Q000517:prevention & control; D012042:Registries; D012189:Retrospective Studies; D012307:Risk Factors; D016019:Survival Analysis; D013997:Time Factors; D014481:United States / Q000453:epidemiology; D044465:White People; D001741:Black or African American