What does HER2 negative mean?
HER2 (Human Epidermal Growth Factor Receptor 2) testing is used to measure levels of a specific protein in breast cancer cells. When a breast cancer is HER2-negative, it means the cancer cells have normal or low levels of the HER2 protein.
This status is important because it helps determine Show Full Answer
What does HER2 negative mean?
HER2 (Human Epidermal Growth Factor Receptor 2) testing is used to measure levels of a specific protein in breast cancer cells. When a breast cancer is HER2-negative, it means the cancer cells have normal or low levels of the HER2 protein.
This status is important because it helps determine your treatment options. HER2-negative breast cancers do not typically respond to targeted therapies that block the HER2 protein, so your doctor will recommend other appropriate treatment approaches. Testing for HER2 status can be done in two main ways:
• Immunohistochemistry (IHC) - measures the amount of HER2 protein
• Fluorescence in situ hybridization (FISH) - measures levels of the HER2 gene
Your doctor will use these results to develop the most effective treatment plan for your specific type of breast cancer.
August 26, 2025