No significant difference in breast-cancer survival found between black and white women

Underinsured black women were more likely to have advanced breast cancer at diagnosis and worse OS when compared with underinsured white women with breast cancer. However, the effect of race on survival was no longer statistically significant after adjusting for clinical and sociodemographic factors.

In this study, researchers pooled records for all patients treated at Wishard Memorial Hospital for a primary breast cancer. Breast cancer outcomes were compared between underinsured black women (n=315) and underinsured white women (n=259) treated between Jan.1, 1997, and Feb. 28, 2006.

Median time to follow-up was 80.3 months for white women and 77.9 month for black women. Eighty-four percent of the total cohort was underinsured.

The researchers found that black women presented with more advanced disease compared with white women. In addition, black women were more likely to present with ER-negative (41% vs. 31% for whites), PR-negative (56% vs. 44% for whites) and triple-negative tumors (32% vs. 19% for whites).

Both groups had a similar median time from diagnosis to operation, adequate surgery, and similar usage of adjuvant therapy and follow-up time.

Despite this, breast cancer specific mortality was significantly increased in black women when compared with white women (26% vs. 17.5%; P=.028; HR=1.64).

However, the effect of race on breast cancer survival was no longer statistically significant after adjusting for age at diagnosis, clinical stage and hormone receptor status (HR=1.43; 95% CI, 0.89-2.30). The HR for race was further attenuated after adjustment for sociodemographic factors (HR=1.26; 95% CI, 0.79-2.0).

Despite previous data suggesting black women are less likely than white women to receive adjuvant therapy, the researchers found that the use of all types of adjuvant therapy were similar between the two groups.

“This difference may reflect the fact that all of the women in this study had similar access to and use of health care and were treated by the same physicians, who had the same resources and who followed the same indications for determining the need for adjuvant therapies,” the researchers wrote. “Therefore, when [black] and [white] patients have equivalent access to breast cancer care and similar socioeconomic limitations and are treated by the same physicians, they appear to make similar choices about their use of adjuvant therapies.”

Komenaka IK. J Natl Cancer Inst. 2010; 102:doi:10.1093/jnci/djp215.