Types of hormonal therapy
There are different types of hormonal therapy for breast cancer. The type of hormonal therapy recommended for women with hormone receptor-positive breast cancer depends on whether the woman has reached menopause
Anti-oestrogens work by stopping breast cancer cells from getting oestrogen. The most common anti-oestrogen is tamoxifen. Tamoxifen can be used to treat women of any age, regardless of whether they have reached menopause. Tamoxifen is taken as a single tablet every day, usually for 5 years.
Fulvestrant (Faslodex®) is another anti-oestrogen that is sometimes used in the treatment of metastatic breast cancer. It is given as a monthly injection into the muscle of the buttock. It may be recommended if other hormonal therapies have stopped working or if a woman cannot take tablets because she’s feeling sick.
Aromatase inhibitors work by stopping androgens from being changed to oestrogen. Examples of aromatase inhibitors include anastrozole (Arimidex®), letrozole (Femara®) and exemestane (Aromasin®). Aromatase inhibitors are only effective for women who have gone through menopause permanently.
Aromatase inhibitors are not suitable for women who:
- haven’t yet reached menopause
- are in the middle of menopause
- have temporarily stopped having menstrual periods because of chemotherapy.
Aromatase inhibitors are taken as a single tablet every day, usually for 5 years.
Ovarian treatments work by stopping the ovaries from making oestrogen. Drugs like goserelin (Zoladex®) stop the ovaries from making oestrogen temporarily. They only work while the woman is taking the drug. This is called ovarian suppression.
Oestrogen production can be stopped permanently by removing the ovaries surgically (oophorectomy) or giving radiotherapy to the ovaries. Ovarian treatments are only suitable for women who have not yet reached menopause.
Progestins are artificial forms of the female hormone progesterone. They are sometimes used for women with metastatic breast cancer. The most common progestins are megestrol acetate (Megace®) and medroxyprogesterone (Provera®). Progestins are given as a tablet.