Triple-negative breast cancer (TNBC) accounts for about 10-15% of all breast cancers. The term triple-negative breast cancer refers to the fact that the cancer cells don’t have estrogen or progesterone receptors and also don’t make too much of the protein called HER2. (The cells test “negative” on all 3 tests.) These cancers tend to be more common in women younger than age 40, who are African-American, or who have a BRCA1 mutation.
Triple-negative breast cancer differs from other types of invasive breast cancer in that they grow and spread faster, have limited treatment options, and a worse prognosis (outcome).
Signs and symptoms of triple-negative breast cancer
Triple-negative breast cancer can have the same signs and symptoms as other common types of breast cancer.
How is triple-negative breast cancer diagnosed?
Once a breast cancer diagnosis has been made using imaging tests and a biopsy, the cancer cells will be checked for certain features. If the cells do not have estrogen or progesterone receptors, and also do not make too much of the HER2 protein, the cancer is considered to be triple-negative breast cancer.