Hormones help control how cells grow and what they do in the body. The hormones oestrogen and progesterone can both encourage breast cancer cells to grow, but particularly oestrogen.
Hormonal therapies lower the level of oestrogen in the body, or block it from attaching to the cancer cells. They only work for women who have oestrogen receptor (ER) positive cancers. They are often the first treatment for women with ER-positive breast cancer when the cancer is mainly in the bones. But if the cancer has spread to other organs as well, you usually have chemotherapy first and then hormonal therapy.
There are different hormonal therapies. The type you have depends on:
- whether you have been through menopause or not
- other hormonal therapies you have had before.
Hormonal therapies are usually easy to take. You take most of them as tablets and the side effects are usually quite mild.
Side effects may be more troublesome in the first few months, but they usually get better over time. If you continue to have problems, talk to your breast care nurse or doctor. There are usually ways that side effects can be treated or managed.
Some side effects are similar to menopausal symptoms and certain hormonal therapies cause a temporary or permanent menopause.
It takes a few weeks or months before your doctors can tell how well your treatment is working for you. If one treatment doesn’t work, or stops working, your cancer doctor may prescribe another type.