Arizona Cancer Center study shows Hispanic women more prone to aggressive breast cancer

[Source: Donna Breckenridge, AzCC] - Results of a study published this week in the Journal of Health Care for the Poor and Underserved indicate that when compared with Non-Hispanic White women, Hispanic women in the state of Arizona are more likely to have high-grade breast cancers, larger tumors, a greater number of positive lymph nodes, and advanced stage at diagnosis. Study results also indicate that Hispanic women are less likely to have tumors that are both estrogen and progesterone receptor positive, particularly in those under age 60. This is important because hormone-dependent tumors differ with respect to their biology, and these differences affect the type of treatment used, patient response to treatment, and patient prognosis.

“Breast cancer is an understudied and poorly understood disease in the U.S. Hispanic population, and we need to understand the magnitude and profile of breast cancer in our Latina population,” says María Elena Martínez, PhD, co-director of the Arizona Cancer Center’s Cancer Prevention and Control Program and principal investigator for the study. “This study confirms our suspicions that the profile of tumor presentation in Hispanic women in Arizona is consistent with a more aggressive disease pattern and less favorable prognosis than that of Non-Hispanic Whites.”

Researchers used data from the Arizona Cancer Registry to assess differences in tumor characteristics. A total of 25,494 invasive breast cancer cases (23,657 non-Hispanic Whites and 1,837 Hispanics) reported to the cancer registry from 1995 to 2003 were included in the analysis.

In the U.S., the rate of breast cancer incidence is higher among non-Hispanic Whites and lower among other racial/ethnic groups, including Hispanics. However, among Hispanic women, breast cancer is the most commonly diagnosed cancer and is the leading cause of cancer death. In addition, data indicate that breast cancer is presenting at an earlier age among Hispanics in the U.S. Preliminary data also suggest a higher risk of breast cancer may exist for those Latinas born in the U.S. than in those born in Mexico who are living in the U.S. The study was funded in 2006 as part of two grants from the Avon Foundation and the National Cancer Institute totaling approximately $1.2 million. The grants are enabling researchers in the U.S. and Mexico to undertake a binational (U.S. and Mexico) research study assessing the specific types of breast cancer occurring in Latinas in both countries.

In addition to Dr. Martínez, most of the other authors of the study are also affiliated with the Arizona Cancer Center, University of Arizona, including Drs. Raymond B. Nagle, Ana Maria Lopez, and Patricia Thompson. Drs. Christina Kim and Carrie M. Nielsen were also affiliated with the Arizona Cancer Center at the time of manuscript submission.The Journal of Health Care for the Poor and Underserved is a publication of Johns Hopkins University and will be available online the week of Dec. 3.