HER2
Also known as: HER2/neu, ERBB2
A growth protein over-expressed in some breast and stomach cancers, which can be targeted with specific drugs.
Definition
HER2 (human epidermal growth factor receptor 2) is a protein on the surface of cells that promotes growth. About 15–20% of breast cancers and a smaller proportion of stomach cancers make far too much HER2 ("HER2-positive"), which makes them grow more quickly.
HER2-positive tumours are identified using IHC and FISH testing on the biopsy. Importantly, several highly effective targeted drugs — including trastuzumab and pertuzumab — specifically block HER2 and have transformed outcomes for HER2-positive disease.
See also
- Targeted Therapy — Drugs designed to attack specific molecules involved in cancer growth, with less harm to normal cells.
- Immunohistochemistry (IHC) — A laboratory test that uses antibodies to detect specific proteins in tumour tissue.
- EGFR — A protein on the surface of some cancer cells that can be blocked by targeted drugs.
- Genetic Testing — Tests that examine genes to find inherited risk or to guide cancer treatment.
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Medically reviewed by
Dr. Rehan Abdullah
Dr. Rehan Abdullah is a dual-trained clinical and radiation oncologist with over a decade of experience treating both solid tumours and hematologic malignancies. He serves as Consultant Oncologist at INMOL Hospital and sees patients at Farooq Hospital and Healthnox Medical Center, Lahore. Read full profile →
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