In the United States, African-American women have a lower incidence of breast cancer than white women, but they have a higher mortality rate. The disease also develops at an earlier age and is more aggressive in African-American women. To explore the reasons for the differences, Beth A. Jones, assistant professor in the Department of Epidemiology and Public Health at Yale School of Medicine, and her colleagues studied the effects of alterations in a tumor suppressor gene called p53.
The team looked at how the patterns of alterations of genes related to worse prognosis differed between African-American and white women. They examined the breast tumors of 145 African-American and 177 white women and found that African-American women were four times more likely than white women to show significant alterations in the p53 gene.
"This is the first population-based study to report a clearly significant increase in p53 mutations that is independent of race differences in other tumor characteristics, socioeconomic status and other biomedical and lifestyle factors", said Jones. The authors also confirmed that tumors in African-American women were more likely than those in whites to display tumor characteristics associated with poor prognosis. With few population-based studies having access to detailed patient information and tumor information assessed in a single laboratory using standardized methodology, Jones said confirmation of these earlier reports is an important contribution to this area of research.
Past explanations for the racial/ethnic differences included socioeconomic factors, nutrition and healthcare behavior, but Jones stresses that while many factors contribute to the relatively poor outcome for some African-American breast cancer patients, understanding the underlying mechanisms is critical.
"Our goal is to continue to illuminate the reasons for the differences, so we can ultimately develop prevention strategies and tailor treatments more effectively," said Jones.
Other authors on the study include Stanislav V. Kasl, Christine L. Howe, Mary Lachman, Robert Dubrow, Mary McCrea Curnen, Hosanna Soler-Vila, Alicia Beeghly, Fenghai Duan and Patricia Owens.
Citation: Cancer(online): August 9, 2004, Print issue: September 15, 2004.
Journal
Cancer