Ovarian suppression (sometimes called ovarian ablation) is the medical term used to prevent the ovaries from producing oestrogen, either temporarily or permanently.
All women produce a hormone called oestrogen which stimulates some breast cancers to grow. If oestrogen stimulates your breast cancer to grow it is known as oestrogen receptor positive breast cancer or ER+ breast cancer.
Before the menopause, oestrogen is mainly produced by the ovaries. If the ovaries are removed or stopped from working there is less oestrogen in the body to stimulate the cancer to grow. Fat cells will still produce small quantities of oestrogen.
Who may be offered ovarian suppression?
Ovarian suppression may be needed if you’ve not yet reached the menopause (pre-menopausal) and your breast cancer is oestrogen receptor positive.
It may also be used to try to protect your fertility during chemotherapy.
It’s also sometimes used to shrink and control breast cancer that has spread.
Recent research suggests that some women who remain pre-menopausal after chemotherapy may benefit from ovarian suppression, as it reduces the risk of the cancer coming back. Older pre-menopausal women (over the age of 40) may not get as much benefit from ovarian suppression.
Your medical team should discuss what the best treatment plan is for you and why.
What does it involve?
Ovarian suppression can be achieved by:
- hormone therapy (drug therapy)
Your specialist team should help you decide which is best for you. Ovarian suppression using hormone therapy is the only form of ovarian suppression that may not be permanent. This may be something to consider when making your decision especially if you want to have children.
Certain drugs ‘switch off’ oestrogen being made by the ovaries. They interfere with signals from the brain that control how the ovaries work.
One of the drugs most commonly used is goserelin (Zoladex). Goserelin comes as an implant or a small pellet given as an injection under the skin (subcutaneously) into your tummy area (abdomen). It is usually given every 28 days. You may still be able to get pregnant while having goserelin treatment but the drug could harm a developing baby so talk to your doctor about contraception.
An operation to remove the ovaries is called an oophorectomy. The fallopian tubes, which are close to the ovaries, are usually removed at the same time. The surgery is done under a general anaesthetic.
It can be done as ‘keyhole’ surgery, which means an instrument called a laparoscope (a flexible thin tube with a camera lens attached) is used so that the surgeon can look into the abdomen. There are usually three small cuts made; one near the belly button, one near the bikini line and one on the side of the abdomen.
Sometimes it isn’t possible for the ovaries to be removed through ‘keyhole’ surgery. In this case the ovaries are removed through a short incision made below the bikini line.
Removing the ovaries will mean an immediate and permanent menopause. This means that your periods will stop straight away.
Ovarian suppression combined with tamoxifen or aromatase inhibitors
The most common treatment for pre-menopausal women with oestrogen receptor positive breast cancer has been tamoxifen. There are ongoing studies testing the benefit of combining ovarian suppression with hormone treatments such as tamoxifen or aromatase inhibitors. Some recent research suggests that an aromatase inhibitor combined with ovarian suppression may reduce breast cancer recurrence more than tamoxifen combined with ovarian suppression.
Your specialist team should discuss this if they think it would help you.
Side effects of ovarian suppression
During a natural menopause the ovaries stop producing oestrogen and some women get menopausal symptoms such as hot flushes, night sweats, vaginal dryness and loss of sex drive. The removal of the ovaries or their suppression can also cause menopausal symptoms.
Experiencing a sudden menopause can mean these symptoms come on more quickly and may be more intense than with a natural menopause.
In the long term, there is some concern that women who have an early menopause because of treatment for breast cancer are more at risk of heart disease and osteoporosis (thinning of the bones) in later life.
Some women with primary breast cancer having ovarian suppression treatment will be offered a baseline bone density scan (DEXA scan). Read more about osteoporosis and reducing your risk.
Other sources of support
The Younger Breast Cancer Network (UK) is a private Facebook group for younger women who’ve had breast cancer. If you have a Facebook profile, you can find the group by searching on Facebook for ‘younger breast cancer network’.