Hormone receptor status

After you were diagnosed with breast cancer, you should have had a number of tests to help your doctors learn more about the cancer and how to treat it. You can find your test results in a document called your pathology report.

One of those tests checked the cancer’s hormone receptor status. This test checks whether the cancer cells have receptors for the hormones estrogen and progesterone. Receptors on the surface of breast cancer cells work like satellite dishes. They detect and bring in hormone signals. These signals can direct cells to grow, multiply, and repair damage.

Hormone receptor-positive disease is the most common subtype of breast cancer. These breast cancers test positive for the estrogen receptor, the progesterone receptor, or both. This means the breast cancer cells are sensitive to estrogen and progesterone, and grow in their presence.

Is hormone receptor testing standard?

It’s standard practice to test all invasive breast cancer tumors and breast cancer recurrences for estrogen and progesterone receptors. Immunohistochemistry or IHC is the most common test used to test for hormone receptors.

Why is hormone receptor testing important?

Knowing the hormone status helps your doctors predict whether the breast cancer you have will respond to hormonal therapies. Hormonal therapy blocks the effects of estrogen or lowers its levels in the body, with the goal of slowing or stopping cancer growth.

The test results help you get the most appropriate treatment for the type of breast cancer you have. They could also help you avoid medicines that won’t work, along with the side effects those medicines can cause.

How and when is testing done?

Testing is usually done on tissue taken during the biopsy, when cells or tissues are taken so a pathologist can look at them under a microscope. Tests may also be done during surgery to remove the cancer.

How will the results be given?

You will see the results of your hormone receptor testing in your pathology report:

• Positive: The cancer cells have estrogen or progesterone receptors. The cancer cells may test positive for one or both hormone receptors. Positive means these hormones are likely to fuel the growth of the cancer cells.
  • You will see a percentage, rating or other number that explains how sensitive the cancer is to hormones. The higher the percentage or rating, the more sensitive.
  • The American Society of Clinical Oncology recommends that a tumor be considered hormone-positive if at least 1 percent of the cells have estrogen or progesterone receptors.
• Negative: Estrogen and progesterone do not fuel the growth of the cancer cells.

Other things to remember

Testing for hormone receptor status should be done by an accredited lab that follows specific testing procedures. Not all labs use the same testing method, nor do they report the results in exactly the same way. Ask your treatment team to explain your results and how they affect your treatment options.