Most breast cancer cells usually have receptors for the hormones estrogen, human epidermal growth factor receptor 2 (HER2), and progesterone. The presence of these receptors frequently helps the cancer to develop. About 15 percent of women with breast cancer, however, test negative for these three receptors, and thus, are said to have triple-negative breast cancer. A triple-negative breast cancer usually is unresponsive to most therapies used in the treatment of breast cancer. It is frequently associated to a basal-type breast cancer, which contains cancer cells similar to the cells lining the ducts of the breast.
Triple-negative breast cancer is generally considered an aggressive type of cancer. It can spread to other parts of the body, even to the brain. Most triple-negative breast cancer cases are of a higher grade than other breast cancer types. The more abnormal the cancer cells appear as compared to the normal tissues, the higher the grading usually is. When a cancer case is given a high grade, the cancer is said to grow and spread faster.
Knowing the types of receptors present in the cancer cells is often important in the treatment of breast cancer patients. Oncologists, doctors who treat patients with cancer, may request a breast biopsy in order to identify these receptors. A breast biopsy is a procedure where breast tissues are removed and examined in a laboratory.
When estrogen or progesterone receptors are found, hormone therapies are often used in the treatment. Examples of these treatments include the drugs tamoxifen, fulvestrant, and anastrozole. Those with HER2 receptors are usually given medications like trastuzumab and lapatinib, which target the HER2 receptor and stop the growth of cancer cells. Unfortunately, in triple-negative breast cancer patients, these types of treatment cannot be used.
The treatment often used in women with triple-negative breast cancer includes chemotherapy, which uses drugs, or a combination of drugs, to kill the cancer cells. This is usually given after the patient has undergone surgery for the removal of the breast cancer. Studies have shown, however, that after treatment with chemotherapy, triple-negative breast cancer may come back in other areas of the body.
Women with increased risks for triple-negative breast cancer are those who are of African lineage and those in the premenopausal stage. The premenopausal stage is the period before menopause, which is usually around the age of 45. During menopause, the ovaries stop functioning and menstruation ceases.
