Hormone receptor tests
The hormone receptor test measures the amount of certain proteins (called hormone receptors) in cancer tissue.
Hormones that naturally occur in the body (such as estrogen and progesterone) can attach to these proteins. If the test is positive, it indicates that the hormone is probably helping the cancer cells to grow. In this case, hormone therapy may be given to block the way the hormone works and help keep the hormone away from the cancer cells (hormone receptors). If the test is negative, the hormone does not affect the growth of the cancer cells, and other effective cancer treatments may be given.