HER2-positive breast cancer occurs when breast cells contain too many copies of a particular gene and excessive amounts of the protein that gene produces. Normal breast cells contain two copies of the HER2 gene and produce the HER2 protein needed for normal growth and division of breast cells. (HER2 stands for human epidermal growth factor receptor 2 -- a protein that acts as a receptor on breast cancer cells.) In people with HER2-positive breast cancer, the breast tumor cells contain many more HER2 genes and consequently too much HER2 protein. That can make the breast cancer cells divide and grow faster than healthy cells or even other types of cancer cells. For this reason, HER2-positive breast cancer can be an especially aggressive form of breast cancer, one that may progress more rapidly and be more likely to recur.
In recent years, doctors have developed treatments targeted specifically toward this type of breast cancer. These treatments have improved the prognosis of women with HER2-positive breast cancer.
HER2-positive breast cancer occurs when breast cells contain too
many copies of a particular gene and excessive amounts of the
protein that gene produces. Normal breast cells contain two copies
of the HER2 gene and produce the HER2 protein...
More
Stacy Wiegman answered:HER2-positive breast cancer occurs when breast cells contain too many copies of a particular gene and excessive amounts of the protein that gene produces. Normal breast cells contain two copies of the HER2 gene and produce the HER2 protein needed for normal growth and division of breast cells. (HER2 stands for human epidermal growth factor receptor 2 -- a protein that acts as a receptor on breast cancer cells.) In people with HER2-positive breast cancer, the breast tumor cells contain many more HER2 genes and consequently too much HER2 protein. That can make the breast cancer cells divide and grow faster than healthy cells or even other types of cancer cells. For this reason, HER2-positive breast cancer can be an especially aggressive form of breast cancer, one that may progress more rapidly and be more likely to recur.
