According to the National Cancer Institute (NCI), it is estimated that approximately 192,000 women are diagnosed with breast cancer each year in the United States. If you are one of these women, it is important to maintain an open dialogue with your oncologist to make sure that you receive the best treatment possible, which includes knowing whether or not your breast cancer is HER2-positive (HER2+). A biopsy of your breast tumor needs to be conducted to determine your HER2 status.
HER2 protein expression linked to breast cancer
Innovative research over the past two decades has yielded a better understanding of how certain genes or proteins stimulate the growth of certain cancers. Scientists discovered that breast cancer may overexpress a protein called HER2 (human epidermal growth factor receptor-2), which causes this particular form of breast cancer to have a poorer prognosis compared to breast tumors that do not overexpress HER2. In fact, HER2+ breast cancer tends to grow more aggressively (faster) and has a greater likelihood of coming back after going into first remission. It is estimated that anywhere from 20 to 25 percent of women with breast cancer have HER2+ positive breast cancer.
Currently, there are two targeted therapies that were specially designed to treat women whose tumors overexpress the HER-2 protein. Herceptin (trastuzumab), a monoclonal antibody that is given intravenously, works by attaching itself on the HER2 protein that appears on the surface of the breast cancer cell. Tykerb (lapatinib), a pill, works by entering the breast cancer cell and attaching itself to the HER2 protein that is found just beneath the surface of the cell.
HER2 Positive Breast Cancer Survival Rate