HER2 (ERBB2)
HER2 (ERBB2) is a protein found on the surface of cells that helps control cell growth, and which some cancers make in larger-than-normal amounts.
HER2 (also called ERBB2) is a protein found on the surface of cells; in normal cells it helps control cell growth. When cancer cells make too much HER2, those cells may grow more quickly and be more likely to spread to other parts of the body. Doctors test tumors for HER2 because, per the NCI, checking whether a cancer is HER2 positive may help plan treatment.
NCI: checking to see if a cancer is HER2 positive may help plan treatment.
breast cancer · bladder cancer · pancreatic cancer · ovarian cancer · stomach cancer
This is general information from authoritative sources, not medical advice. What a specific test result means for your case is a question for your treating oncologist.