Moreover, researchers are working on finding new medicines to target both triple- negative and HER2-negative cancers.

Triple-Negative Breast Cancer Lacks 3 Key Receptors

Estrogen receptors (ER)Progesterone receptors (PR)Human epidermal growth factor receptor 2 (HER2)

Because triple-negative breast cancers lack these receptors, typical medicines that target estrogen, progesterone, and HER2 are ineffective. Triple-negative breast cancers can be more aggressive and more challenging to treat. But every case is different, and your prognosis will depend on many factors.

HER2-Negative Breast Cancer Is Missing the HER2 Protein

However, most HER-2 negative cancers are ER- and PR-positive, so they are treated very effectively with hormone therapy. Knowing your HER2-status is important, because this information will determine your treatment options.

Testing for Triple-Negative and HER2-Negative Cancers

Typically, this is done with a biopsy. During a biopsy procedure, a surgeon removes a small amount of tissue and sends it to the lab. A pathologist will examine the tissue and determine its hormone receptor status. Other tests will also be performed to see if it’s HER2-positive or HER2-negative.

Treatments for HER2-Negative and Triple-Negative Cancers

If your tumor is HER2-negative and triple negative, there are still treatments available to help your particular type of breast cancer. Women with triple negative cancer are usually candidates for chemotherapy, surgery, radiation therapy, targeted therapies, and immunotherapies.  Many people who have triple-negative breast cancer are treated with chemotherapy prior to surgery, and patients with stage 2 or 3 triple-negative breast cancer may be candidates for immunotherapy (with a drug called pembrolizumab) combined with chemotherapy prior to surgery. If you have HER2-positive breast cancer but you are negative for hormone receptors, your doctors will talk with you about regimens that combine chemotherapy and HER2-targeted therapy. If your cancer is stage 2 or stage 3, this will likely be given prior to surgery, but if your cancer is stage 1, the HER2-targeted therapy and chemotherapy can be given after surgery. If your cancer is HER2-negative but hormone receptor–positive (ER+, PR+, or both), you will receive endocrine therapy. Depending on other features of your cancer, your doctor may recommend chemotherapy as well.

Clinical Trials for HER2-Negative and Triple Negative Breast Cancer

Some women who have triple negative and HER2-negative breast cancers choose to participate in clinical trials to test therapies that aren’t yet available to the public. Additionally, clinical trials help researchers determine whether new treatments are safe and effective. You can search for a clinical trial in your area at ClinicalTrials.gov.

Your Prognosis Depends on Several Factors

The size of your cancerWhether your tumor has spread to other areas of your bodyThe type of breast cancer you haveThe hormone receptor and HER2 status of your tumorWhether your cancer is triple-negativeThe rate of cell growthHow likely your cancer is to come backWhether your cancer is newly diagnosed or a recurrenceYour age and menopausal statusYour general health

Each person is different, and your doctor will likely run several tests before giving you a formal prognosis.

Coping With Your Breast Cancer Diagnosis

Receiving a breast cancer diagnosis can be scary, especially when you hear that your type of cancer may not benefit from standard therapies.

Focus on yourself. A healthy diet, daily exercise, and adequate sleep can help your body cope with side effects from cancer treatment. Research shows that managing stress and staying positive can be helpful throughout diagnosis and treatment. Activities like prayer, meditation, walking, deep-breathing, and other relaxation techniques to calm your mind and body can also be beneficial.Ask for, and accept, help. Ask family members or friends to help with household chores, rides to appointments, or managing paperwork, and accept help when it’s offered.Join a support group. A support group can be a great way to connect with other people dealing with similar situations. Many organizations, including CancerCare, offer online or in-person support groups. The Triple-Negative Breast Cancer Foundation’s online discussion forums provide 24/7 support.