Increased risk for breast cancer death among black women is greatest during early postdiagnosis years

Non-Hispanic black women with breast cancer, specifically estrogen-positive tumors, are at a significantly increased risk for breast cancer death compared with non-Hispanic white women. The difference is greatest in the first 3 years after diagnosis.

Prior research has shown that non-Hispanic black women have a lower breast cancer survival rate relative to other racial/ethnic groups. This research included 19,480 women who presented to National Comprehensive Cancer Network (NCCN) centers with stage I to stage III breast cancer between January 2000 and December 2007. Breast cancer-specific mortality was compared among 634 Asian women, 1,291 Hispanic women, 1,500 non-Hispanic black women, and 16,055 non-Hispanic white women. The median follow-up was 6.9 years.

The non-Hispanic black women had a 48% higher risk for breast cancer death in the first 3 years after diagnosis compared with non-Hispanic white women. After 3 years, non-Hispanic black women had a 34% increased risk for breast cancer-specific mortality.

Those non-Hispanic black women whose tumors were estrogen receptor-positive were more than twice as likely to die from breast cancer within 3 years of diagnosis compared with non-Hispanic white women. This risk was also increased in non-Hispanic black women with luminal A and luminal B breast cancer subtypes.

“The higher risk for early death among black women was more striking among women with estrogen receptor-positive tumors. This finding is important because these are the types of tumors that we traditionally think of as more treatable,” said Erica Warner, MPH, ScD, postdoctoral fellow at the Harvard School of Public Health. Breast cancer mortality had no difference between non-Hispanic black and white women with estrogen receptor-negative, basal, or HER2-overexpressing tumor subtypes.

“The results of this study emphasize that clinical management and follow-up for patients with breast cancer, particularly black women, is important in the first few years after diagnosis,” Warner said. “Although the difference between blacks and whites was highest for this time period, the risk for death was highest in the first few years after diagnosis for all groups.”

This data was presented at the Fifth American Association for Cancer Research Conference on The Science of Cancer Health Disparities in San Diego.