Also known as: Oestrogen receptor (ER), progesterone receptor (PR)
Name: Oestrogen and progesterone receptors
Related tests: HER2/neu, Tumour markers, Cancer
Why is the test done?
To determine whether a breast cancer is oestrogen and/or progesterone receptor-positive. Whether or not the receptors are present affects the choice of treatment and the prognosis.
When is it done?
When breast cancer has been diagnosed, to establish whether the growth of the tumour is influenced by oestrogen and/or progesterone.
What samples are required?
A sample of breast tumour tissue obtained by biopsy, or the tumour mass removed surgically during a mastectomy or lumpectomy, is required.
What is being tested?
The oestrogen receptor (ER) and the progesterone receptor (PR) are specialised proteins found inside some cells of the body. These receptors promote cell growth and division by binding oestrogen and progesterone, female hormones that circulate in the blood.
Many breast cancers have oestrogen and/or progesterone receptors, often in large numbers. These tumours are considered hormone-dependent, and oestrogen and/or progesterone promote their growth. The tumour tissue can be tested to check whether it is positive for these receptors.
How is the sample collected for testing?
A sample of tumour tissue collected by fine-needle aspiration or biopsy, or removed surgically by lumpectomy or mastectomy, is tested.
How is it used?
When is it requested?
What does the test result mean?
Is there anything else I should know?
How is it used?
Hormone receptor expression is a prognostic indicator. Oestrogen and progesterone receptor-positive tumours tend to have a better prognosis than tumours without these receptors.
Hormone receptor expression is also used to decide on the treatment strategy, which includes endocrine therapy (anti-hormone treatments such as tamoxifen), after removal of a primary tumour, or to guide treatment decisions in the event of recurrence.
When is it requested?
Hormone receptor testing is recommended as an integral part of the initial assessment of an invasive breast cancer. It is not a diagnostic test, but it helps in choosing treatment and in understanding the characteristics of the tumour.
What does the test result mean?
In general, if a tumour is oestrogen and progesterone receptor-positive, the prognosis will be better than average, because the tumour is likely to respond to endocrine therapy (anti-hormone treatments). The greater the receptor expression, the stronger the reaction and the more likely the response to therapy. However, individual response depends on many factors.
An ER-negative but PR-positive tumour may still respond to endocrine therapy, although the response is weaker.
An ER-negative and PR-negative tumour is unlikely to respond to endocrine therapy.
Is there anything else I should know?
The HER2/neu test may be ordered at the same time as hormone receptor testing. A tumour that is oestrogen and/or progesterone receptor-positive may respond less well to endocrine therapy if it is also HER2/neu-positive.
Hormone receptor testing is not available in all laboratories. Performing and interpreting this test requires experience and appropriate training. The sample may therefore be sent to a reference laboratory, and it may take a few weeks for the result to be ready.
Hormone receptor testing requires small amounts of tumour tissue. If not enough sample is available, the tumour is assumed to be ER and PR hormone receptor-positive so as to widen the treatment options.
1. Is there a blood test to check hormone receptor expression?
1. Is there a blood test to check hormone receptor expression?
No. Tumour cells do not release the receptors, so they cannot be measured in the blood. They must be measured in the tumour tissue itself.