Ethnic background may play a role in a woman’s risk of breast cancer, as one recent study found that American women who are black, American Indian, Hawaiian, Pakistani or of other non-white descents had an increased risk of being diagnosed with advanced breast cancer than whites.

The national study included 125,000 American women with breast cancer from 17 races and ethnic groups. Study data showed that blacks, American Indians, Hawaiians, Vietnamese, Mexicans, South and Central Americans and Puerto Ricans were 20 percent to 200 percent more likely to die after being diagnosed with breast cancer than non-Hispanic white women.

Researchers suggested that economic, social and cultural factors might explain the gap. Included factors, such as access to health insurance, could delay diagnosis or affect treatment. The chance of being diagnosed with advanced breast cancer, along with the risk of mortality from it, is strongly influenced by access to health care. Blacks, American Indians, Hawaiians, Indians, and Pakistanis, Mexicans, South and Central Americans and Puerto Ricans had a 1.4 to 3.6 times greater risk of being diagnosed with advanced breast cancer than non-Hispanic whites, study data showed.

Cultural and personal factors can also affect risk, researchers said. For example, non-Hispanic white women tended to be older than others when receiving a breast cancer diagnosis. These women tend to use hormone replacement therapy more often, which can increase the risk of postmenopausal breast cancer.

Further, treatment methods varied by race and ethnicity. Black, American Indian, and Hispanic white women more likely to refuse surgery or undergo a surgery outside of national cancer guidelines, and less likely to undergo radiation therapy than non-Hispanic white women.

The study did not take into account the affect of socioeconomic status, access to healthcare, use of mammograms and hormones, and chemotherapy on mortality rates, researchers note.

Archives of Internal Medicine January 13, 2003;163:49-56