Effects of screening mammography on the comparative survival rates of African American, white, and Hispanic beneficiaries of a comprehensive health care system

Abstract

This study reviewed mammographic screening related to breast carcinoma diagnosis and treatment between 1987 and 1997 at Brooke Army Medical Center, San Antonio, TX. Epidemiologic data from the Department of Defense Automated Central Tumor Registry were merged with data from patients' medical records and responses of the patients or their families to a mailed survey. The cases of 907 women grouped by race-white, African American, and Hispanic-were analyzed. Breast carcinoma diagnosed by mammographic screening showed a reversed ratio of early to late stage of cancer occurring for all three groups. That ratio was 1.45 for African Americans, 2.67 for Hispanics, and 3.08 for whites. For those women diagnosed with screening mammography, no statistically significant difference in 5-year survival was found between the races: 86% for whites, 83% for Hispanics, and 80% for African Americans. Mammographic screening as a diagnostic tool appears to equalize survival among whites, Hispanics, and African Americans, in spite of differences in age, stage of diagnosis, and military rank used as a proxy for socioeconomic status. When not controlling for mammographic diagnosis, Kaplan-Meier analysis revealed significant differences in survival patterns between whites, Hispanics, and African Americans. Five-year survival rates were 71% for whites, 74% for Hispanics, and 53% for African Americans. Screening mammography reduced 5-year mortality by almost 59% in African Americans, 52% in whites, and 36% in Hispanics. Whites were diagnosed with breast carcinoma, on average, at 57 years of age-11 years later than African Americans (average age 46 years) and 7 years later than Hispanic women (average age 50 years). As a diagnostic tool, screening mammography was used to discover breast cancer in 36% of white women, 33% of Hispanics, and 22% of African Americans. Further research is recommended to examine the use of mammography among various racial/ethnic groups.