Blood-tests Explained


Disclaimer:

This website is intended to assist with patient education and should not be used as a diagnostic, treatment or prescription service, forum or platform. Always consult your own healthcare practitioner for a more personalised and detailed opinion

Estrogen/Progesterone Receptors


At a Glance

Why Get Tested?

The hormone receptor test determines if a breast cancer tumor is positive for estrogen and progesterone receptors, helping to guide treatment and determine prognosis

When to Get Tested?

When you have been diagnosed with invasive breast cancer or when your cancer has recurred

Sample Required?

A sample of breast cancer tissue obtained during a biopsy or a tumor removed surgically during a lumpectomy or mastectomy

Test Preparation Needed?

Your health practitioner may have you discontinue taking hormones for a time period before your sample is collected.

The Test Sample

What is being tested?

Receptors are specialized proteins on the surface of or within cells that recognize and bind to other substances. The binding typically has a specific effect on the cells. Many, but not all, breast cancer cells have receptors that bind to the hormones estrogen and progesterone. Breast cancer tumors with estrogen receptors (ER) and progesterone receptors (PR) depend on the hormones to grow and divide. ER and PR testing of breast tumor tissue determines if one or both types of receptors are present.

Knowing if a tumor depends on hormones to grow helps a health practitioner determine a person's risk of breast cancer recurrence and whether it can be treated with hormone therapy to block estrogen and progesterone. About two-thirds of breast cancer tissues are positive for both ER and PR.

In 2010, the American Society of Clinical Oncology (ASCO) and the College of American Pathologists (CAP) jointly published guidelines that recommend that all tumors from individuals with newly diagnosed invasive breast cancer be evaluated for estrogen and progesterone receptors. The guidelines also state that all recurrent breast cancers should be tested and that the option of testing should be provided for patients who have non-invasive breast cancer.

How is the sample collected for testing?

A sample of breast cancer tissue is obtained by doing a fine needle aspiration, needle biopsy, or surgical biopsy, or a tumor is removed surgically during a lumpectomy or mastectomy.

Is any test preparation needed to ensure the quality of the sample?

Your health practitioner may have you discontinue taking hormones for a time period before your sample is collected.

The Test