Blacks more likely to have aggressive tumors

Highly aggressive tumors that portend a poor prognosis characterize the type of breast cancer most often diagnosed in black women with the disease, researchers report in a new analysis.

Dr. Gloria Morris and colleagues at Thomas Jefferson University Hospital in Philadelphia found that breast cancers in black women were more likely to be typified by a so-called "triple negative" status, meaning they lack specific surface proteins on tumors that make them amenable to treatment.
Reporting in the journal Cancer, a publication of the American Cancer Society, Morris wrote that black women with the disease have a 67 percent higher chance of dying from breast cancer than white women. She said that being black may be a "prognostic indicator of worse outcome."

Having "triple negative status" means black women lack proteins on their cancers for estrogen, progesterone and the HER-2 oncogene, Morris explained. Doctors, therefore, cannot offer patients such drugs as tamoxifen, which is prescribed to women whose tumors are marked with estrogen and progesterone receptors. The drug blocks the receptors, preventing the hormones from fueling new cancers. A newer type of estrogen-blocking medication called an aromatase inhibitor also is ineffective.

Even though the HER-2 oncogene is a marker for an aggressive form of breast cancer, since 1998 doctors have been able to offer the 20 to 25 percent of women who possess it a targeted breast cancer drug known as Herceptin. The medication has helped improve outcomes for women with advanced and early-stage disease.

"Right now we're very limited in the drugs we can use," Morris said.

Morris and her collaborators studied grade, stage and degree of invasiveness of breast cancers diagnosed in 2,200 women at Thomas Jefferson's Kimmel Cancer Center. They compared that data to 197,274 women in a National Cancer Institute database and found that black women with the disease were more likely to have tumors that bore markers for poor prognosis. Nearly half of all black women in the local and national databases had the difficult-to-treat tumor type compared with 37 percent of white women.

"We need a targeted drug that exploits the weaknesses of this tumor type," said Dr. Lisa Carey, director of medical oncology at the UNC Breast Center, who identified the biology of triple negative tumors last year. She gave such cancers the name "basal-like" and defined them as among the most aggressive.

Dr. Lovell Jones, director of the Center for Research on Minority Health at M.D. Anderson Cancer Center in Houston, said hard-to-treat breast cancer is most prevalent in black women under the age of 40. Some of the cancers, he said, are being diagnosed in women as young as 25.

Dr. Edith Mitchell, Morris' Jefferson colleague, said multiple issues underlie the problem. "There are social problems as well as medical problems that account for health disparities in this country," she said. "There is a lack of access to care for many black women that accounts for higher death rates. But there are some biological differences in the tumors."

source : www.newsday.com