American Cancer Society: 90% of white women, but only 76% of African-American women, diagnosed with breast cancer will live at least five years

Erin Allday:

For decades, doctors assumed the lower survival rate was due primarily to societal issues -- most importantly, that black women were less likely to have health insurance, and therefore less likely to get mammograms that can spot early, and highly treatable, cancers. Health care access is still considered a part of the problem.

But in the past two or three years, research has focused on the biological differences between the cancers that attack black women and white women. Black women are more likely to get breast cancer at a younger age, and their tumors tend to be more aggressive and harder to treat.

"There's certainly a lot of interest now to look at the genetics of breast cancer," said Esther John, an epidemiologist with the Northern California Cancer Center. "Maybe it's a genetic profile among African American women that explains what's going on. But we need more research."

On Saturday, the cancer center is hosting an educational conference in Oakland for women and their families, as well as health care professionals, to address issues that are specific to black women living with breast cancer.

Societal issues no doubt play a significant role in death rates, researchers say. Some published studies show that black women are far less likely to get regular mammograms than white women, which could lead to delayed diagnoses and complicate treatment.

Plus, black women are less likely to have health insurance and more likely to live in low-income areas where it's difficult to find top-notch cancer care. They are more likely to be single moms who can't afford to take time off work to get the treatment they need, said Pamela Ratliff, who heads the community education program for the cancer center.

In response to these societal factors, public health officials for years have focused resources on providing free or low-cost mammograms to minority women and supporting breast cancer clinics in low-income communities.

San Francisco public health officials created a special task force on breast cancer when studies showed that rates in Bayview-Hunters Point rivaled rates in Marin County, which has among the highest incidences of breast cancer in the country.

But even when black women get an early diagnosis and timely treatment, they are still more likely to die from breast cancer, according to recent research.

"Newer data is suggesting that African American women do seem to have worse cancers, and that the biology of their cancer seems to be worse as a group than it is for Caucasian women," said Dr. Christy Russell, chairwoman of the breast cancer advisory group for the American Cancer Society.

Black women have increased rates of what doctors call "triple negative" breast cancer -- rare tumors that are not driven by estrogen, progesterone or a mutation in the Her-2 gene, Russell said. These tumors are particularly difficult to treat, because they do not respond to certain therapies -- such as Tamoxifen and Aromatase inhibitors -- that have been helpful in preventing breast cancer recurrences.

Between the unusual tumors and the fact that black women are more likely than white women to get breast cancer at a young age, researchers say genetics almost definitely plays an important role in the higher death rate among African Americans.

But identifying the biological reasons behind the death rate isn't easy. Most national studies into breast cancer are focused on white women -- mostly because white women are more likely to sign up for a study. It's only recently that researchers have started studies to look specifically at black women and other minorities, and it takes time to build those studies and get results from them.

"It's similar to when we looked at heart disease trials that were all done on men, and we wondered why women didn't have the same results -- well, because they're women. The same is true for African American women now," said Dr. Susan Kutner, a surgeon at Kaiser Permanente Santa Teresa Medical Center in San Jose who chairs Kaiser's Regional Breast Care Task Force.

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