Updated Nov. 10, 2008 – Anyone who has read anything lately about breast cancer in African American women lately has most likely heard the term triple negative breast cancer. What is it? Is it something African American women in particular need to be concerned about? BET.com went to an expert for answers. Dr. Worta McCaskill-Stevens, a cancer doctor and Program Director for the Community Oncology and Prevention Trials Research Group at the National Cancer Institute, took time to provide us with some answers.
Q. What is triple-negative breast cancer and why should African American women be concerned about it?
A. Dr. McCaskill-Stevens: We have been able to use technology in the profiling of genes to determine that breast cancer is really more than one disease. This has allowed us to understand that there are at least five types of breast cancer. One type of breast cancer is triple-negative breast cancer.
Q. So, most breast cancer cells need the hormone estrogen to grow. That's why they are called estrogen-dependent or estrogen-receptor positive (ER+) cancers, right?
A. Dr. McCaskill-Steven: We know that the breast is responsive to hormones – for instance, there are hormones that the body emits to tell the breasts of a young girl to develop when she reaches puberty or that it’s time for feeding when a mother is about to have a baby.
We have very good evidence that estrogen (a hormone) plays a part in promoting breast cancer. So, when breast cancer treatment was first developed, hormone receptors were targeted for the treatment of breast cancer with hormone drug therapies like tamoxifen and aromatase inhibiters. These drugs block estrogen from attaching itself to breast cancer cells. Estrogen receptor-negative breast cancer patients don’t respond to hormonal therapy. The rate of estrogen receptor negative breast cancer is higher in African American women at each age group than for White women.
Within the category of estrogen-negative breast cancer, there is triple-negative breast cancer which is estrogen receptor negative, progesterone (another hormone) receptor negative and HER2 receptor negative. HER2 (Human Epidermal Growth Factor Receptor) is a gene involved in the growth of breast cancer. Triple-negative breast cancer is not new, but our ability to identify whether a person’s breast cancer is HER2 positive or normal is relatively new. The North Carolina Breast Cancer Study found that triple negative breast cancer was much higher among younger African American women than in White women (39 percent for Blacks versus 16 percent for Whites).
Q. Does this mean that triple-negative breast cancer can’t be treated?
Dr. McCaskill-Stevens: No. We know that estrogen receptor-negative breast cancer respond to chemotherapy. We do not know which chemotherapy is best. For women who are HER2 positive, the drug trastuzumab is highly effective in reducing risk of recurrence and survival. We also don’t know if this triple-negative breast cancer behaves differently in African American than it does in White women who get this type of breast cancer. Several studies suggest that from a treatment standpoint, there may not be any difference in outcome between different races, if treatment is received timely and at the prescribed doses.
The take-home point is that yes, triple-negative breast cancer is a sub-type of breast cancer which tends to occur more often in African American, pre-menopausal women who get breast cancer than it does for White women in the same group. African American women with this type of cancer should not delay or forgo treatment. In fact, you should seek treatment earlier because this type of cancer tends to grow rapidly so the earlier you get treatment clearly the better the outcome.