Triple-negative breast cancer is when cancer growth does not involve estrogen receptors, progesterone receptors and human epidermal growth factor (HER2) receptors.
As such, triple-negative breast cancer does not respond to hormone therapy, meaning individuals with this subtype have a poorer prognosis than those with other subtypes. Basal cell breast cancer is the most common form of triple-negative breast cancer.
Fast facts about triple-negative breast cancer
Triple-negative breast cancer is more likely to occur before the age of 40 or 50, while other breast cancers are more common among people over the age of 60
People with a BRCA1 gene mutation are at increased risk of triple-negative breast cancer
Treatment for triple-negative breast cancer usually involves a combination of surgery, radiation therapy and chemotherapy.