Hormone therapy

(Courtesy of Macmillan Cancer Support)

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.

Hormones exist naturally in the body. They help to control how cells grow and what they do in the body. Hormones, particularly oestrogen, can encourage some breast cancer cells to grow.
Hormonal therapies work by lowering the level of oestrogen in the body, or by preventing oestrogen from attaching to the cancer cells. They only work for women who have oestrogen-receptor positive cancers.

Hormonal therapies are given to reduce the chance of breast cancer coming back and to protect the other breast. They can work in different ways and are usually given for a number of years. You’ll start hormonal therapy after you have finished chemotherapy (if you’re having it). Hormonal therapies can also be used before surgery to shrink a large cancer to avoid the need for a mastectomy.
Hormonal therapies are usually well tolerated. Sometimes side effects are more troublesome in the first few months but get better over time. If you continue to have problems, talk them over with your specialist nurse or doctor, as there are ways of reducing some of the effects.

The type of hormonal therapy you have usually depends on:

  • whether or not you’ve been through the menopause
  • the risk of the cancer coming back
  • how side effects of the drugs are likely to affect you.

Your cancer specialist will explain which drug or drugs and the length of time they’re given for is best in your situation.
We have more information about individual hormonal therapy drugs.

Hormonal therapy for women who are postmenopausal

After the menopause, oestrogen is no longer produced by the ovaries, but is still produced from hormones in the fatty tissues of the body. If you’ve been through the menopause, you may be treated with:

  • an aromatase inhibitor such as anastrozole (Arimidex®), letrozole (Femara®) or exemestane (Aromasin®).
  • the anti-oestrogen drug tamoxifen and an aromatase inhibitor (one type is given after the other)
  • tamoxifen.

Hormonal therapy for women who are premenopausal

Before the menopause, the ovaries mainly produce oestrogen. If you haven’t been through the menopause, you may be offered hormonal treatment with:

  • the anti-oestrogen drug tamoxifen
  • a pituitary down-regulator drug, such as goserelin (Zoladex®), to stop the ovaries from producing oestrogen (ovarian suppression)
  • surgery to remove the ovaries (ovarian ablation)
  • a combination of tamoxifen with either Zoladex or ovarian ablation (this may be an option for women who don’t want to have chemotherapy).

In premenopausal women, some hormonal treatments bring on a temporary or permanent menopause. Women who have an early menopause will have a scan called a DEXA (dual-energy x-ray absorptiometry) scan to assess their bone health.

If you’re at risk of bone thinning (osteoporosis), your cancer specialist may prescribe drugs called bisphosphonates to protect your bones. You will probably also be advised to take calcium and vitamin D supplements to help with your bone strength – your cancer specialist can tell you more about this.

Information on individual drugs:

Aromatase inhibitors 

Continuing to take your hormonal therapy

Hormonal therapy reduces the risk of breast cancer coming back, so it’s important to take it for as long as your cancer specialist prescribes it.

If you’re finding the side effects difficult to cope with, tell your cancer specialist or nurse. They can prescribe drugs to help and advise you on other ways of coping. If the side effects don’t improve and are very troublesome, your cancer specialist may suggest switching to a different type of AI or to tamoxifen. And if you’re having problems with tamoxifen, you may be advised to switch to an AI.

If you find it hard to remember to take your tablet every day, it can help to build taking it into your daily routine so it becomes a habit. These tips may also help:

  • Take your medicine at the same time as something else you do at the same time every day, such as when you’re having your lunch or dinner.
  • Put your tablets in a place where you’ll see them every day.
  • Use a 7-day pill container.
  • Keep a supply with you when you travel and take them in your carry-on luggage when you fly. 

If you want the South West Wales Breast Cancer Network Breast cancer treatment details please follow this link: