To diagnose breast cancer, oncologists will look for ‘receptors,’ which are proteins inside or on the surface of a cell. You may have heard of the terms estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2). In these cancers, treatments prevent, slow, or stop cancer growth with drugs targeting those receptors. However, triple-negative breast cancers need different types of treatments because they are estrogen receptor-negative, progesterone receptor-negative, and HER2 negative. Because hormones do not support their growth, they are unlikely to respond to hormonal therapies including tamoxifen, Femara, Aromasin, Arimidex, and Faslodex. They are also unresponsive to medications like Herceptin that target HER2 receptors.
Some features of triple-negative breast cancer:
• More aggressive than other breast cancer types and spread beyond the breast with a higher chance of recurrence. Five-year survival rates are lower than other cancers of the breast.
• High grade compared to other breast cancers.
• Cell type is ‘basal-like,’ which means that the cells resemble the basal cells present in the breast ducts.
Triple-negative breast cancer can be treated with chemotherapy and radiation treatment. The Triple Negative Breast Cancer Foundation offers free clinical trials that may be beneficial for patients with triple-negative breast cancer. More details are available here.