African-American women with two or more children who did not breast-feed them may face a substantially higher risk of getting an aggressive form of breast cancer, according to a study published in Cancer Epidemiology, Biomarkers & Prevention (a journal of the American Association for Cancer Research) and reported by Agence France Presse.

For this study, researchers at the Slone Epidemiology Center at Boston University analyzed data from the Black Women’s Health Study, which has followed 59,000 women since 1995. During a 14-year period, 457 women developed hormone receptor-positive breast cancer, and 318 others got hormone receptor-negative breast cancer.

In the group of participants who developed hormone receptor-positive breast cancer (an easier-to-treat cancer more commonly found among white women), researchers found no connection between cancer development and the number of children women had and their breast-feeding history. But researchers found that non-breast-feeding women with two or more children faced a 50 percent increased risk of hormone receptor-negative breast cancer (a tougher-to-treat cancer).

“African-American women are more likely to have had a greater number of full-term births and less likely to have breast-fed their babies,” said lead author Julie Palmer, MPH, ScD, a professor of epidemiology at Slone. “This study shows a clear link between that and hormone receptor-negative breast cancer.”

Scientists know that while black women have lower breast cancer incidence rates, they also suffer from the highest cancer death rates and more often face resistant tumors. But the good news is these findings, along with other recent study results of triple negative cancers, suggest breast feeding may help African-American women reduce their risk of developing difficult-to-treat breast cancers, Palmer said.

The other toughie is possibly connected to cultural traditions. According to the Centers for Disease Control and Prevention, about 35 percent of white women in the United States are breast-feeding their babies at 6 months old, compared with 20 percent of black women.

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