Black women more likely to have dense breast tissue, study shows

New research finds that black women are more likely than white women to have dense breasts, potentially boosting their breast cancer risk.

"Since breast density is associated with breast cancer risk, a better understanding of racial differences in breast density levels could help us identify women at the highest risk for breast cancer and target prevention strategies to those women," study author Anne Marie McCarthy, said in a news release from the American Association for Cancer Research. McCarthy is a research fellow at Massachusetts General Hospital in Boston.

In terms of both volume and area, black women had denser breasts than white women, even after researchers adjusted their statistics so they wouldn't be thrown off by factors such as high or low numbers of women of certain ages or weights.

Denser breasts make it harder to detect breast cancer via mammogram, and they're thought to boost the risk for the disease. For this study, researchers said they used a better technique to measure breast density than that traditionally used by radiologists.

The study included almost 1,600 black women and more than 1,250 white women who were screened using mammography from 2010 to 2011 at the University of Pennsylvania.

"Our findings are using a new, quantitative and, perhaps, more reliable way to measure breast density," McCarthy explained. "Our next step will be to see how quantitative density measures and other imaging biomarkers are associated with cancer risk, cancer subtype and stage of diagnosis by race."

Genes and Breast Cancer

Breast cancer is often discussed as a general condition, but there are several different types that require different treatments.

One way to distinguish breast cancer cells is through your genes. When you’re diagnosed with breast cancer, your doctor will test the cancerous cells to determine their genetic makeup.

Read through to learn what it means if the genes in your cancer cells have more HER2 protein than they should.

HER2 Basics

HER2 is a protein that stimulates the growth of breast cancer cells. It can be found in your blood and urine. Sometimes it’s referred to as a "tumor marker."

Tumor markers like HER2 can’t be used for cancer diagnosis, but they can provide other important information. For example, the presence of HER2 can help your doctor predict how your breast cancer is likely to respond to treatment.

How Many Are HER2-Positive?

The Mayo Clinic estimates that about 20 percent of breast cancers are HER2-positive. Younger women are more likely to be HER2-positive than older women.