Knowing which receptors your breast cancer has is important for planning your treatment
Knowing whether your breast cancer cells have certain markers, called receptors, is extremely helpful in planning which treatments may be effective for you.
A receptor acts like a keyhole, allow a matching molecule to lock onto it and signal to the cell. For example, hormones can lock onto hormone receptors on breast cancer cells and signal to them to grow faster.
The sample of your tumour (biopsy) taken during your diagnostic tests will be tested for the presence of:
- Oestrogen receptors (sometimes known as ER)
- A receptor called HER2
Some hospitals may also test for progesterone receptors (sometimes known as PR) but this is not as useful for planning your treatment.
Sometimes the biopsy may need to be repeated to get clear receptor test results. Occasionally receptor tests can only be performed on your tumour once it has been removed by surgery so your breast care team may not be able to explain all your test results and treatment options until after you have had surgery.
You will not normally need to have receptor tests if you have been diagnosed with ductal carcinoma in situ (DCIS).
What do my results mean?
Breast cancers that have oestrogen receptors are called hormone positive or oestrogen receptor positive (ER positive) breast cancers. Around four in five breast cancers are hormone positive.
If you have a hormone positive breast cancer, your breast care team should offer you hormone therapies such as tamoxifen or aromatase inhibitors. This doesn’t mean that these will be the only treatments you’ll receive – your breast care team may recommend other treatments too.
Breast cancers that have a lot of HER2 are known as HER2 positive breast cancers. Around one in five breast cancers are HER2 positive. Some breast cancers can be both HER2 positive and ER positive.
If you have HER2 positive breast cancer, your breast care team should offer you the targeted therapy trastuzumab (Herceptin). This may sometimes be combined with another targeted therapy called pertuzumab (Perjeta), although this is only available on the NHS in England, Wales, and in some cases Northern Ireland. This doesn’t mean that these will be the only treatments you’ll receive – your breast care team may recommend other treatments too.
Some breast cancers do not have oestrogen receptors, progesterone receptors, or HER2. This type of breast cancer is known as triple negative breast cancer. Neither hormone therapy nor trastuzumab (Herceptin) will work for you if you have triple negative breast cancer, but chemotherapy may be an effective treatment for you.
Breast Cancer Now’s health information is produced following best practice guidelines developed by the Patient Information Forum.
Find out more about how we develop our health information and the Patient Information Forum.