Underinsured African-American women die more often from breast cancer than underinsured white women, even when treated at the same hospital by the same doctors, researchers said Wednesday.

And it’s not because they get different treatment, the researchers said.

“When you have the same physician pretty much giving the same treatment to all women, then African-Americans will make the same treatment decisions as everybody else,” said Dr. Ian K. Komenaka, of Wishard Memorial Hospital in Indianapolis, who led the study.

Among nearly 600 women treated at his hospital, he and his colleagues found that most had no insurance or only had Medicare or Medicaid. After 10 years, they estimated breast cancer deaths at 26 percent in African-American women and 18 percent in non-Hispanic white women.

“There is not an easy answer to what the difference is,” Komenaka told Reuters Health.

But his findings, which appear in the Journal of the National Cancer Institute, point to several possible reasons. The survival disparity between African-American and white women appears to be due, at least in part, to differences in tumor characteristics and other “clinical” variables, as well as social and demographic factors between the two groups.

When they accounted for the women’s age and whether they had a job, as well as the tumor stage and biochemical makeup, the racial difference vanished.

“There are several factors which may be important,” Komenaka said. “The difference in risk is very complex.”

In future studies, the researchers hope to clarify the causes of racial and ethnic differences in overall survival among women with breast cancer.

SOURCE:  Journal of the National Cancer Institute, online June 23, 2010.