African-American Breast Cancer Survival Lags

CancerWise - July 2007

Survival rates for African-American women with advanced breast cancer have not improved over the last two decades, despite modest improvements in survival for women overall, and researchers say the difference in life expectancy between white and black women continues to widen.

Significance of results

This study is the first to show the widening gap in survival rates, says the study’s senior author Sharon Giordano, M.D., an assistant professor in M. D. Anderson’s Department of Breast Medical Oncology.

Research methods

Researchers analyzed the National Cancer Institute's Surveillance Epidemiology and End Results (SEER) database to identify 15,438 women who were newly diagnosed with advanced breast cancer between 1988 and 2003. The median age was 62. They were divided into three groups.

Patients were divided by their diagnosis date:

• 1988 to 1993
• 1994 to 1998
• 1999 to 2003

Primary results

Women diagnosed between 1988 and 1993 had:

• Median survival of 20 months if they were white
• Median survival of 17 months if they were African-American
• A one-year survival difference of 2.8%

Women diagnosed between 1994 and 1998 had:

• Median survival of 27 months if they were white
• Median survival of 16 months if they were African-American
• A one-year survival difference of 6.8%

Women diagnosed between 1999 and 2003 had:

• Median survival of 27 months if they were white
• Median survival of 17 months if they were African-American
• A one-year survival difference of 8.8%

"We do not suspect that these statistics are due to the biology of the disease because we would not expect the biology to change over time," Giordano says.

"While SEER data does not code for treatment, we hypothesize that two contributing factors for the growing disparity are lack of access to health care and lack of access to newer types of treatment for Stage IV breast cancer, such as targeted therapies, including the drug Herceptin and the class of drugs known as aromatase inhibitors."

Background

The study evolved as a follow-up to previous research by Giordano that found an overall improvement in the survival of Stage IV breast cancer patients enrolled in clinical trials at M. D. Anderson.

"We wanted to expand our research and look to a bigger subset of patients treated in the community to see if we would find similar results," says Shaheena Dawood, M.D., a Susan G. Komen fellow in the Department of Breast Medical Oncology. "We thought we would find that there was improvement in women with Stage IV breast cancer regardless if patients were white or black. Rather, over the decades, we found that black women's survival did not improve at all."

What's next?

Giordano and Dawood intend to expand their research and determine the cause of these racial disparities.

Resources:

• Breast cancer
• Overview: Breast Cancer (American Cancer Society)
• Breast Center (M. D. Anderson)