Estrogen Receptor, Progesterone Receptor Tests

What are Estrogen and Progesterone Receptor Tests?

Estrogen and progesterone receptor tests are specific diagnostic tests conducted to detect the presence of and the amount of the two hormones, estrogen and progesterone, in a patient's body. These tests are often ordered for women with breast cancer, as the presence of certain levels of these hormones can have an effect on treatment and patient outcome.

Preparation for Estrogen and Progesterone Receptor Tests

No special preparation is required before an estrogen and progesterone receptor test. However, it is important to let your healthcare provider know about any medications you may be taking, as some of them can interfere with the results.

Procedure for Estrogen and Progesterone Receptor Tests

Estrogen and progesterone receptor tests are done on a sample of tissue taken during a biopsy, usually from a breast lump. The sample is examined in the lab to determine the presence of and the number of receptors for each hormone. The result of the tests is reported as either positive or negative, along with the number of receptors present.

Types of Estrogen and Progesterone Receptor Tests

The two types of estrogen and progesterone receptor tests are:

• Quantitative receptor tests – These tests measure the amount of hormones in the patient's body.
• Qualitative receptor tests – These tests detect whether or not the patient's body has the receptors for the hormones.

Risks of Estrogen and Progesterone Receptor Tests

There are no known risks associated with estrogen and progesterone receptor tests. The procedure is minimally invasive and does not cause discomfort.

Why Estrogen and Progesterone Receptor Tests are Done

Estrogen and progesterone receptor tests are done to determine whether or not the breast cancer cells are dependent on either estrogen or progesterone for growth. This information helps the doctor to choose the best treatment plan for the patient. Patients with higher numbers of receptors are more likely to respond positively to hormone therapies such as tamoxifen.

When Estrogen and Progesterone Receptor Tests are Done

Estrogen and progesterone receptor tests are usually done when a woman is diagnosed with breast cancer. The tests are also done to determine if a patient is a candidate for hormone therapy, or if the tumor is growing in spite of treatment.