About hormone therapy

What is hormone therapy?

Some cancers use hormones to grow. These cancers are known as hormone-dependent cancers. They include some types of breast, uterine and prostate cancers.

Hormone therapy is also known as androgen deprivation therapy, endocrine therapy or hormone-blocking therapy. 

Hormone therapy to treat cancer is not the same thing as hormone replacement therapy, which is used to replace hormones that the body is no longer able to produce naturally. For example: 

• menopause hormone therapy (MHT) is used to treat the symptoms of menopause 
• thyroid hormone replacement therapy is given to people who have had their whole thyroid removed. 

How hormone therapy works

Hormone therapy uses hormones, which have been produced in a laboratory, to slow or stop the effect of the body’s natural hormones. The aim is to lower the amount of hormones the tumour receives. This can help reduce the size and slow down the spread of the cancer. It can also reduce the risk of the cancer returning after treatment. 

Hormone therapy for breast cancer

About 70–80% of breast cancers are sensitive to the hormones oestrogen (ER) or progesterone (PR). This means that these hormones may be helping the cancers grow. These cancers are called hormone receptor positive (ER+ and/or PR+), and they are likely to respond to hormone therapy that blocks oestrogen. 

There are different ways to reduce the level of oestrogen and progesterone in the body, including medicines such as tamoxifen or aromatase inhibitors, and drugs or surgery to stop the ovaries producing oestrogen (ovarian suppression). The choice will depend on your age, the type of breast cancer and − for women − whether you have reached menopause. 

Learn more about Hormone therapy for breast cancer.

Hormone therapy for cancer of the uterus

Some cancers of the uterus need oestrogen or progesterone to grow. Hormone therapy may be given if the cancer has spread or come back, particularly if it is a low-grade cancer. It is also sometimes offered as the first treatment for early stage uterine cancer instead of surgery, for example, if having children is important. The main hormone treatment for hormone-dependent cancer of the uterus is progesterone.  

Learn more about Hormone therapy for cancer of the uterus.

Androgen deprivation therapy for prostate cancer

Prostate cancer needs testosterone to grow. Testosterone is an androgen (male sex hormone), so hormone therapy for prostate cancer is called androgen-deprivation therapy (ADT). Reducing how much testosterone your body makes may slow the cancer’s growth or shrink it temporarily. ADT may be recommended for locally advanced or advanced prostate cancer. There are different types of ADT, including injections and tablets. Less commonly, one or both testicles may be removed to lower testosterone production. 

Learn more about Androgen deprivation therapy for prostate cancer.