FRIDAY, Jan. 14 (HealthDay News) -- In an ongoing effort to shed light on the reason for racial disparities in breast cancer prognosis, researchers in North Carolina report new findings from their research on black women and breast cancer.

Previous research has shown that breast cancer in younger black women in the United States is more likely to be the more aggressive basal-like (triple-negative) subtype, which may help explain why black women are more likely to die from breast cancer than other women.

In this new study, researchers analyzed tissue from 518 black women and 631 white women with invasive breast cancer who were enrolled in the Carolina Breast Cancer Study.

"Our data show that basal-like breast cancer is an equally aggressive disease in African-American women and white women," study co-author Charles M. Perou, a professor of genetics and pathology at the University of North Carolina at Chapel Hill School of Medicine, said in a university news release.

"In addition, African-American women had worse outcomes no matter what kind of breast cancer they developed, suggesting that other factors such as disparities in access to care and treatment, for example for the more common subtypes of breast cancer like luminal A breast cancer, also contribute to the higher breast cancer mortality observed in African-American women," Perou said.

The data suggest that it may not be possible to "identify a truly good prognosis subtype [of breast cancer] in African-American women and we need to find out why," study co-author Dr. Lisa Carey said in the news release.

The study was published in a recent issue of the journal Clinical Cancer Research.

More information

WomensHealth.gov has more about black women and breast cancer.