One in five invasive breast cancers is HER2-positive, making this one of the more common breast cancer subtypes in the United States. HER2-positive cancers are ER and PR negative and human epidermal growth factor receptor 2 (HER2) positive.
HER2-positive breast cancer cells carry too many copies of the HER2 gene, which makes HER2-protein receptors, found on breast cells. When they work normally, HER2 receptors control how a healthy breast cell grows, divides and repairs itself. When they proliferate, the receptors tell the cells to divide and grow rapidly and without control. That’s because their cells absorb too much of a substance called human epidermal growth factor 2, which energizes cell growth. Doctors often test breast cancer tissue for excess HER2-positive genes to determine whether the patient may benefit from targeted therapy options, which are designed to block HER2 from energizing cancer cell growth.
Symptoms of HER2-positive breast cancer are similar to those of other breast cancer types. They include a lump in the breast, changes to the breast’s shape, pain, swelling and abnormal discharge.
Treatments for HER2-positive breast cancer
Depending on the cancer’s stage
, treatment options for HER2-positive breast cancer may include a combination of surgery
, radiation therapy
and/or administration of a targeted therapy
such as the immune monoclonal antibody, trastuzumab
(Herceptin®). Learn more about advanced treatments for breast cancer.