North Carolina researchers report new results from their investigation on black women and breast cancer in an effort to gather latest information on racial differences in breast cancer prognosis.

According to previous research, breast cancer in younger black women in the United States appears to be more of the aggressive basal-like subtype, which is a triple-negative cancer, that could help explain why black women have an increased chance to die from breast cancer in comparison to other women.

Data in the new study showed basal-like breast cancer is an equally aggressive disease in both African-American women and white women, co-author of the study Charles M. Perou said in a university news release. The study can be found at the recent issue of the journal Clinical Cancer Research.

The researchers examined tissue from 518 black women and 631 white women who were enrolled in the Carolina Breast Cancer Study. The women were diagnosed with invasive breast cancer.

Perou is a professor of genetics and pathology at the Universe of North Carolina Chapel Hill School of Medicine. He also added based on the results of their study that Africam-American women had worse outcomes no matter what type of breast cancer they developed.

This suggests other factors such as differences in access to care and treatment and the more common subtypes of breast cancer like luminal A breast cancer could lead to the higher breast cancer mortality rate in African-American women.

On the other hand, based on study-co author Dr. Lisa Carey during the news release, the data imply that it may not be possible to identify a truly good prognosis of a breast cancer subtype in African-American women and that they need to find out why.