The hormone receptor status of your breast cancer refers to whether your breast cancer cells are fueled by estrogen and/or progesterone (the naturally occurring hormones in the female body) due to unique proteins inside the tumor cells, called hormone receptors. When hormones attach to hormone receptors, the cancer cells grow.
If your cancer appears to be aggressive and fast-growing, you might have higher levels of a protein called human epidermal growth factor receptor 2, or HER2 for short. Some genes, like HER2, and the proteins they make, do more than play a role in the development of breast cancer. They can also influence how your breast cancer behaves as well as how it may respond to specific cancer treatments.
Usually, HER2 receptors help control how a healthy breast cell grows, divides, and repairs itself. However, if the HER2 gene doesn’t work correctly and produces too many copies of itself, it leads to the uncontrolled growth of breast cancer cells.
If your breast cancer is HER2-negative, you do not have an excess of the HER2 gene. Tumors such as these will not respond to therapies that specifically target HER2 receptors.
If your breast cancer is HER2-positive, then you have too much HER2 protein or extra copies of the HER2 gene. These breast cancers tend to be fast-growing. HER2-positive breast cancer treatment typically includes targeted therapy drugs that slow the growth and kill these cancer cells. HER2-positive breast cancers account for about 25% of all breast cancer cases.
Triple-negative breast cancer is a breast cancer type that lacks estrogen receptors, progesterone receptors, and HER2 receptors. Unlike other types of breast cancer, triple-negative breast cancer does not present these receptors on the cancer cells. Because of this, breast cancer treatments that involve hormone blockers targeting estrogen-positive or progesterone-positive cancers are likely ineffective. Additionally, targeted therapies designed to counteract the presence of HER2 protein are also ineffective for treating triple-negative breast cancer.
Treating triple-negative breast cancer often includes a combination of approaches, including surgery, radiation therapy, chemotherapy, and sometimes, immunotherapy. Breast cancer research is in progress to find a combination of treatments that can effectively fight this particularly aggressive form of cancer. If you have received a diagnosis of triple-negative breast cancer, you might have the opportunity to participate in a clinical trial as part of the ongoing and significant research efforts aimed at discovering a widely accepted treatment regimen.
Patients newly diagnosed with breast cancer should consult with a breast cancer doctor to understand their specific diagnosis and what to expect next from treatment. Knowing your hormone receptor status will help your WVCI oncologist create the best breast cancer treatment plan for you.