Hormone therapy for advanced breast cancer

Tamoxifen is used to treat pre-menopausal and post-menopausal women, and men with breast cancer. It slows the growth of cancer by blocking the action of oestrogen in the breast.

Tamoxifen is taken as a tablet and the recommended dose for most people is 20mg daily.

It is fully funded and licensed for use in New Zealand.

Fulvestrant is only used in women who are post-menopausal. It works by blocking the action of oestrogen on the cancer cells, and reducing the number of oestrogen receptors.

Fulvestrant is given as an injection into a muscle in your buttock once a month.

It is fully funded and licensed for use in New Zealand for women with a diagnosis of ABC.

Elacestrant is another medicine in this class of selective oestrogen receptor degrader (SERD) and is used in the treatment of ER+ve, HER2-ve breast cancer. It has been approved for use overseas in women or men with ABC whose illness has progressed on another type of hormone therapy.

Elacestrant is not funded or licensed for use in New Zealand.

Aromatase inhibitors are used in women who are post-menopausal. There are three: anastrozole, exemestane and letrozole and they all act to reduce the amount of oestrogen made in the body; no one drug is better than another. If you have been recommended an aromatase inhibitor, your specialist will explain why they have chosen it. Aromatase inhibitors are all used in pre-menopausal women in conjunction with another medication, Goserelin (see below), which stops the ovaries from making oestrogen.

Aromatase inhibitors are taken daily as a tablet and are fully funded and licensed for use in New Zealand.

Goserelin is a hormone therapy used in the pre-menopausal setting to stop the ovaries from producing oestrogen. It can be used alone or in combination with tamoxifen or aromatase inhibitors.

Goserelin is given as a small implant, injected under the skin of the tummy (abdomen) every 28 days or at three-monthly intervals.

It is fully funded and licensed for use in New Zealand.

Surgery to remove the ovaries is called an oophorectomy. The operation is usually done as keyhole surgery using a laparoscope (a flexible thin tube with a light and camera lens attached). The surgeon makes a few small cuts in the tummy area and removes the ovaries through the cuts. It is done under general anaesthetic, usually as a day case.

Removing the ovaries stops your periods straight away – causing immediate and permanent menopause.

This surgery is fully funded in New Zealand.