HER2 Testing

HER2 stands for human epidermal protein receptor 2. It is a gene that creates a protein found on the surface of all breast cells. It is involved in normal cell growth. Genes are the basic units of heredity, passed down from your mother and father. In certain cancers, especially breast cancer, the HER2 gene mutates (changes) and makes extra copies of the gene. When this happens, the HER2 gene makes too much HER2 protein, causing cells to divide and grow too fast. Cancers with high levels of the HER2 protein are referred to as HER2-positive. Cancers with low levels of the protein are referred to as HER2-negative. About 20 percent of breast cancers are HER2-positive.Both types of tests can tell whether you have HER2-positive cancer. Treatments that specifically target HER2-positive carcinoma are often very effective. Other names: human epidermal growth factor receptor 2, ERBB2 amplification, HER2 overexpression, HER2/neu testsHER2 testing is mostly used to find out whether cancer is HER2-positive. It is also sometimes used to see if cancer is responding to treatment or if cancer has returned after treatment. In a surgical biopsy, a surgeon will make alittle cut in your skin to get rid of all or a part of a breast lump. A surgical biopsy is usually done if the lump cannot be reached with a biopsy.