51. Racial differences in survival from breast cancer: results of the National Cancer Institute Black/White Cancer Survival Study
- Author
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Eley, J. William, Hill, Holly A., Chen, Vivien W., Austin, Donald F., Wesley, Margaret N., Muss, Hyman B., Greenberg, Raymond S., Coates, Ralph J., Correa, Pelayo, Redmond, Carol K., Hunter, Carrie P., Herman, Allen A., Kurman, Robert, Blacklow, Robert, Shapiro, Sam, and Edwards, Brenda K.
- Subjects
Breast cancer -- Prognosis ,African American women -- Health aspects ,White women -- Health aspects ,Cancer patients -- Patient outcomes - Abstract
Black women may have a higher death rate from breast cancer than white women because black women seem to have more advanced stages of the disease at diagnosis. Researchers studied 612 black women and 518 white women with breast cancer to identify factors that may influence the outcome of the disease. Results revealed that black women were 2.2 times more likely to die from breast cancer than white women. The strongest contributor to the difference in survival rate was the stage of cancer at diagnosis. Thirty percent of blacks and 18% of whites were diagnosed with stage III or stage IV disease. When researchers controlled for disease stage at diagnosis, black women were still 1.7 times more likely to die from breast cancer than white women. When researchers eliminated differences in tumor pathology and the presence of other diseases, black women were 1.4 times more likely to die from breast cancer than whites. Sociodemographic variables and treatment differences did not significantly affect the death rate., Objective.--To examine the ability of recognized prognostic factors for breast cancer to account for the observed poorer survival in blacks compared with their white counterparts. Design and Participants.--Subjects included 1130 women (612 blacks and 518 whites) aged 20 to 79 years residing in metropolitan Atlanta, Ga, New Orleans, La, or San Francisco/Oakland, Calif, who were diagnosed with primary invasive breast cancer. Information on stage, tumor characteristics, treatment, comorbid conditions, and sociodemographic factors was obtained from personal interview, physician and hospital records, and a pathology review of biopsy and surgical specimens. Main Outcome Measure.--Multivariable survival models were used to estimate the hazard ratio (relative risk of mortality) for blacks compared with whites, adjusting for various combinations of potential explanatory factors. Results.--After controlling for geographic site and age, the risk of dying was 2.2 times (95% confidence interval [CI], 1.8 to 2.8) greater for blacks than whites. Adjustment for stage reduced the risk from 2.2 to 1.7; further adjustment for sociodemographic variables had no effect. Treatment was not a contributing factor once stage and tumor pathology were in the model. After adjusting for stage, treatment, comorbid illness, and pathologic and sociodemographic variables, blacks continued to demonstrate a slightly increased, but not statistically significant, risk of death (hazard ratio=1.3; 95% CI, 1.0 to 1.8). Results were similar for all-cause mortality and breast cancer-specific mortality. Conclusions.--Approximately 75% of the racial difference in survival was explained by the prognostic factors studied. Sociodemographic variables appeared to act largely through racial differences in stage at diagnosis, which may be amenable to change through improved access to and use of screening for black women. (JAMA. 1994;272:947-954)
- Published
- 1994