TriStar Portland - March 02, 2017

Triple negative breast cancer, or TNBC, is diagnosed in about 10 to 20 percent of breast cancer cases. TNBC is more common in younger people ages 40-50, African American or Hispanic women or those with a BRCA1 genetic mutation, especially before the age of 50.

TNBC is diagnosed based on the absence of three receptors, meaning the patient is HER2 negative, ER negative and PR negative. The HER2, ER and PR receptors are drivers for the growth and development of breast cancer.

To understand TNBC, it is important to first understand what these receptors are. Receptors are proteins found inside and on the surface of cells and are the “eyes and ears” of the cell. The receptors receive messages from substances in the bloodstream, then direct the cell on where to go or what to do. HER2- means that the breast tumor does not have extra HER2, a growth-promoting protein on the outside of all breast cells, and will not respond to treatment with drugs that target it. ER negative means the tumor does not have receptors for the estrogen hormone and PR negative means it does not have receptors for the progesterone hormone.

Hormone receptors in healthy breast cells receive messages from estrogen and progesterone hormones for growth and development, but if you are negative to both hormones, it means that those hormones are not supporting the growth of the tumor, which is why triple negative tumors are usually unresponsive to hormone therapy.

Triple negative breast cancer tends to be more aggressive than other types of breast cancer, which means it is more likely to spread beyond the breast and more likely to return after treatment.

In most cases, chemotherapy is a good option for treatment of triple negative breast cancer, as well as radiation therapy or surgery. Triple negative breast cancer is typically treated with a combination of therapies such as surgery, radiation therapy and chemotherapy.

Chemotherapy may be administered before surgery (adjuvant chemotherapy), or after surgery (neoadjuvant chemotherapy). The way your tumor responds to the chemotherapy and surgery treatment combination will usually give doctors more information on your triple negative breast cancer.

Significant advancements have been made in the development of hormonal therapies and HER2- targeted therapies, which work to interfere with drivers of breast cancer and slow the growth of cancer cells. Ongoing clinical trials are being conducted for more effective therapies for TNBC.

If you are diagnosed with TNBC, talk to your doctor or care team about what options are best for you and how to best fight and recover from triple negative breast cancer.