Understanding the presence of hormone receptors and HER2 is an important part of planning breast cancer treatment. When present, specific drugs are available to counteract them.
The oncologists at Blue Ridge Cancer Care take time to carefully review your biopsy and biomarker test results to identify hormones and other genetic changes that may be causing the cancer to grow. Patients throughout Southwest Virginia trust our team for clear answers and personalized care with the latest breast cancer treatments close to home.
What Are Hormone Receptors?
About two-thirds of breast cancers are hormone receptor-positive, meaning they contain receptors for estrogen and/or progesterone on the surface of the cancer cells. When one or both of these hormones attach to the receptors, they cause the cancer to grow. The biopsy report will tell your oncologist if the cancer cells are:
- Estrogen receptor-positive (ER+) or estrogen receptor-negative
- Progesterone receptor-positive (PR+) or progesterone receptor-negative (PR-)
If the cancer is negative for both hormone receptors, it’s considered hormone receptor–negative breast cancer.
What Is HER2?
HER2 (human epidermal growth factor receptor 2) is not a hormone receptor. It is a protein found on the surface of some breast cancer cells that promotes cell growth.
Breast cancers are tested to determine whether they produce too much HER2 protein (HER2-positive) or not (HER2-negative). Some breast cancers overexpress HER2 at lower levels, called HER2-low. This is an important distinction for the oncologist to determine which drugs will be most effective in treating the patient.
Triple-Negative & Triple-Positive Breast Cancer
If the test results show that the breast cancer cells are negative for estrogen, progesterone, and HER2, it’s called triple-negative breast cancer. This distinct subtype accounts for about 10-20% of all breast cancers. It’s also likely that a BRCA1 gene mutation is present. Because triple-negative breast cancer lacks hormone receptors and does not overexpress HER2, it requires a different treatment approach than hormone receptor–positive cancers.
If the breast cancer cells test positive for all three: estrogen, progesterone, and HER2, this is referred to as triple-positive breast cancer. Less than 15% of breast cancers are this type.
Both triple-negative and triple-positive breast cancers tend to grow quickly. For patients with triple-positive breast cancer, several drug therapies are known to work effectively. Triple-negative breast cancer, however, does not respond to hormone therapy or targeted therapy for HER2. A different combination of treatments is recommended, and tests may be run to identify other gene mutations that could be related to the cancer’s growth.
Personalized Breast Cancer Care in Southwest Virginia
The results of these tests during the diagnosis process will play a large role in the path forward for each patient. Some patients may require hormone therapy to block the hormone receptors, while others may need targeted therapy to slow the overgrowth of the HER2 protein. Our tumor board reviews each patient’s specific needs and recommends a treatment plan. Our oncologists are highly trained and experienced in treating breast cancer using the most recent therapies, right here in the Roanoke area.
