Racial variation in tumor stage at diagnosis among Department of Defense beneficiaries

Abstract

Tumor stage at diagnosis often varies by racial/ethnic group, possibly because of inequitable health care access. Within the Department of Defense (DoD) Military Health System, beneficiaries have equal health care access. The objective of this study was to determine whether tumor stage differed between whites and blacks with breast, cervical, colorectal, and prostate cancers, which have effective screening regimens, based on data from the DoD Automated Cancer Tumor Registry from 1990 to 2003. Distributions of tumor stage (localized vs nonlocalized) between whites and blacks in the military were compared stratified by sex, active duty status, and age at diagnosis. Logistic regression was used to further adjust for age, marital status, year of diagnosis, geographic region, military service branch, and tumor grade. Distributions of tumor stage were then compared between the military and general populations. Racial differences in the distribution of stage were significant only among nonactive duty beneficiaries. After adjusting for covariates, earlier stages of breast cancer after age 49 years and prostate cancer after age 64 years were significantly more common among white than black nonactive duty beneficiaries (P < .05), although the absolute difference was minimal for prostate cancer. Racial differences in stage for cervical and colorectal cancers were not significant after adjustment. Compared with the general population, racial differences in the military were similar or were slightly attenuated. Racial disparities in stage at diagnosis were apparent in the DoD equal-access health care system among older nonactive duty beneficiaries. Socioeconomic status, supplemental insurance, cultural beliefs, and biologic factors may be related to these results.