Glossary
Triple-negative breast cancer
(TRIH-pul-NEH-guh-tiv brest KAN-ser)
A type of breast cancer in which the tumor cells do not have estrogen receptors, progesterone receptors, or large amounts of HER2/neu protein on their surface. Knowing whether breast cancer is triple negative is important in planning treatment. Also called ER-negative PR-negative HER2/neu-negative breast cancer and TNBC.
Definition from the National Cancer Institute’s NCI Dictionary of Cancer Terms.