Triple - negative cancers are so called because they do not express receptors for the hormones estrogen and progesterone, nor for HER2 (human epidermal growth factor 2), and hence patients with these cancers are not candidates for treatment with modern hormonal therapies or the highly effective HER2 - targeted drug Herceptin (trastuzumab). (sciencedaily.com)
It is called triple negative because it lacks receptors for the hormones estrogen and progesterone and makes little of a protein called HER2. (sciencedaily.com)
Triple negative breast cancer is a type of breast cancer that does not express receptors for the hormones estrogen and progesterone, or for human epidermal growth factor. (cancerresearch.org)