Hormonal therapies for breast cancer

 

Hormonal therapies are treatments to reduce the levels of hormones in the body or block their effects on cancer cells. They are often given after surgery| , radiotherapy  | and chemotherapy|  for breast cancer to reduce the chance of the cancer coming back.

Hormonal therapies are only effective in women whose cancer cells have receptors for oestrogen and/or progesterone on their surface. This is known as being oestrogen-receptor positive (ER+) or progesterone-receptor positive (PR+). It means that the breast cancer cells are affected by oestrogen or progesterone. These are female hormones that the body produces naturally and that can stimulate breast cancer cells to grow.

Treatment options

There are many different types of hormonal therapy| , and they work in slightly different ways. Hormonal therapies for breast cancer include the drug tamoxifen| , drugs known as aromatase inhibitors| , and treatment to stop the ovaries from working (ovarian ablation| ).

There are many issues to consider when deciding which type of hormonal therapy is appropriate for you, including:

• your age
• whether you have had your menopause (change of life)
• the stage and grade  of the cancer
• which other treatments are being used
• whether the cancer cells are HER2-positive .

Your doctor will be able to discuss which type of hormonal therapy treatment is best for you, based on your relevant medical details.

The side effects will depend on the type of hormonal therapy you are given, but the most common are menopausal symptoms such as hot flushes, vaginal dryness and a reduced sex drive.

Hormonal therapy for postmenopausal women

Postmenopausal women may be offered hormonal treatment with either an anti-oestrogen (such as tamoxifen| ) or an aromatase inhibitor (such as Anastrozole| ), or a combination of the two different types, where one type is given after the other.

Tamoxifen has been the most widely used hormonal therapy for breast cancer and has been shown to be highly effective in reducing the chance of the cancer coming back. Research has shown that for some women, giving aromatase inhibitors instead of tamoxifen, or after a period of tamoxifen treatment, can further reduce the chance of the cancer coming back.

Your doctor will be able to discuss which type of hormonal therapy treatment is best for you, based on all your relevant medical details. You may be advised to have:

• tamoxifen on its own for five years
• an aromatase inhibitor on its own for a few years
• tamoxifen for 2–3 years followed by an aromatase inhibitor for a few years
• tamoxifen for five years followed by an aromatase inhibitor for a few years.

Hormonal therapy for premenopausal women

Premenopausal women may be offered hormonal treatment with:

• an anti-oestrogen medicine (such as tamoxifen )
• treatment to stop the ovaries from producing oestrogen (ovarian ablation). This can be done using surgery, radiotherapy, or a drug called goserelin (Zoladex® ).

Unfortunately, ovarian ablation by surgery or radiotherapy brings on an early menopause, which can be very upsetting, especially for women who were hoping to have children. The effects of medicines are usually temporary. Once treatment has stopped the ovaries will begin working again, usually within six months.

Your doctor may give you a choice between treatments. It’s important to ask any questions you may have to help you make a decision about the right treatment.