WEDNESDAY, Dec. 7 (HealthDay News) -- Hispanic women have a 20 percent greater risk of dying from breast cancer than non-Hispanic white women, according to a new study.
Biological differences in the women's tumors could explain this discrepancy, the researchers suggested.
"This difference may be associated with a tumor phenotype that is less responsive to chemotherapy," Kathy Baumgartner, an epidemiology professor at the School of Public Health and Information Sciences at the University of Louisville, in Kentucky, said in a news release. "Increased awareness of this ethnic disparity is needed to improve survival in Hispanic women with breast cancer."
Researchers looked at breast-cancer risk in 692 Hispanic and non-Hispanic white women in New Mexico from 1992 to 1996. A separate study followed the 577 women with invasive breast cancer until 2008 to assess the differences in survival rates.
Hispanic women were roughly 20 percent more likely to die from breast cancer than non-Hispanic white women. However, Hispanic women's risk dropped to nearly the same rate as the other women after the researchers adjusted for age, progression of their disease, lymph node involvement and estrogen receptor. As a result, they suggested the ethnic difference in breast cancer mortality may be mostly "biologically based."
Researchers also found that Hispanic women who received chemotherapy were about 1.5 times more likely to die from breast cancer than non-Hispanic white women.
The research is slated to be presented Wednesday at the 2011 San Antonio Breast Cancer Symposium.
"It is not clear how much of this ethnic difference in survival is due to socioeconomic factors influencing access to screening and treatment or to biological ones," Baumgartner said in the release. "Some studies suggest that Hispanic women are more likely to develop ER-negative tumors [tumors not driven by estrogen] that are resistant to chemotherapy."
This altered response to chemotherapy could explain the differences in survival rates between Hispanic and non-Hispanic white women, the authors suggested.
Because this research was presented at a medical meeting, the data and conclusions should be viewed as preliminary until published in a peer-reviewed journal.
The U.S. National Cancer Institute provides more information on health disparities among Hispanic women with breast cancer.
-- Mary Elizabeth Dallas
SOURCE: San Antonio Breast Cancer Symposium, news release, Dec. 7, 2011.
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