What is analysed?

Oestrogen receptors and progesterone receptors are specialised proteins found within certain cells that bind to the female hormones oestrogen and progesterone, respectively.

Some breast cancer tumours have receptors for oestrogen and/or progesterone:

• When oestrogen receptors are present, the tumour is called ER-positive.
• When progesterone receptors are present, the tumour is called PR-positive.

Tumours that are ER-positive respond to oestrogen and tumours that are PR-positive respond to progesterone. These hormones also help the tumours to grow.

The oestrogen and receptor test is used to detect if breast cancer tissue is positive for oestrogen and/or progesterone receptors.

What does the result mean?

The result of the analysis indicates whether breast cancer cells have receptors for oestrogen (ER-positive), progesterone (PR-positive), both, or neither.

Why conduct the analysis?

The test is conducted to determine if breast cancer cells are positive for oestrogen and/or progesterone receptors. Hormone receptor-positive breast cancers are more likely to respond to hormone therapy, which will improve prognosis.

When to conduct the analysis?

The test is conducted at the time of breast cancer diagnosis to determine whether the tumour’s growth is influenced by oestrogen and/or progesterone.

What sample is required?

A sample of breast cancer tissue obtained during a biopsy or during surgery (lumpectomy or mastectomy) is required.

Is any prior preparation necessary?

No prior preparation is required.

How is it performed?

The sample is sent to a laboratory, where it is processed and analysed using immunohistochemistry (IHC) or other molecular techniques to detect the presence of oestrogen and progesterone receptors.

What are the normal values?

A negative test result indicates that the breast cancer tissue is ER-negative and/or PR-negative (there are no oestrogen and/or progesterone receptors).

What does having altered values mean?

• ER-positive and PR-positive: Indicates that the breast cancer tumour has receptors for oestrogen and progesterone. The cancer is likely to respond to hormone therapy.
• ER-negative and PR-positive: Indicates that the breast cancer tumour has receptor for progesterone only. The cancer can still benefit from hormone therapy, but it may be less effective.
• ER-negative and PR-negative: Indicates that the breast cancer tumour lacks receptors for oestrogen and progesterone. The cancer probably won’t respond to hormone therapy. Other treatment options should be explored.