Hormone therapy in breast cancer

What is hormone therapy?

Hormone therapy is a treatment prescribed to patients with breast cancers that express hormone receptors, which represents about 80% of cases.

There are basically three types of hormone therapy:

  • Tamoxifen (Nolvadex®): taken orally, it blocks hormone receptors in breast cancer cells
  • Aromatase inhibitors (letrozole - Femara®, anastrozole - Arimidex®, exemestane - Aromasin®): also taken orally, they block the production of estrogens from androgens
  • LH-RH agonists (goserelin - Zoladex®, triptorelin - Decapeptyl®): injected subcutaneously, they put the ovaries at rest


What is the purpose of hormone therapy?

When breast cancer is localized in the breast and possibly in the lymph nodes, i.e. when there are no distant metastases, hormone therapy greatly reduces the risk of metastases appearing later on. It is then a curative treatment, since studies have shown that it strongly reduces the risk of dying from breast cancer. When metastases occur, hormone therapy is used in order to stabilize the progression of the disease and thus improve the patient’s quality of life and survival time.

Type of care

All treatments are implemented on an outpatient basis. LH-RH agonists should be injected subcutaneously every 28 days. Other hormone therapies should be taken orally once a day.


In the absence of metastases, hormone therapy is used as an adjuvant treatment. Its duration is 5 to 10 years, depending on the situation. In the case where there are metastases, the treatment is continued as long as it stabilizes the disease.

How to prepare for it?

As soon as the diagnosis of breast cancer is made, it is important to ask the doctor if there are hormone receptors and if hormone therapy is planned. This allows anticipating treatment, which will usually begin after surgery, chemotherapy (if necessary), and radiation therapy (if indicated).

What happens after the treatment?

When the treatment ends, there is no particular procedure to follow. It is enough to stop taking the medication.

Risks and discomforts

Hormone therapy is usually better tolerated than chemotherapy. However, since it is planned for the long term, it is still a restrictive treatment. Some patients complain about more frequent hot flashes. It is important to talk to your doctor about this so that you can find a way to attenuate this inconvenience. Some people also report weight gain; it is important to maintain regular physical activity and to eat a healthy, balanced diet throughout the course of treatment. As with any medication, hormone therapy may be accompanied by mild nausea. This treatment can also lead to hormonal disturbances that can have an impact on mood and sexual life; here again, it is essential to talk to your doctor without taboos.


Tamoxifen may lead to a slightly increased risk of blood clot formation. It may also cause thickening of the inner lining of the uterus; regular gynecological checkups are recommended. Aromatase inhibitors and LH-RH agonists can accelerate the onset of osteoporosis, which is why follow-up with bone densitometry is recommended. They can also cause joint pain, which can be prevented by regular physical activity.


Patients with a medical history of pulmonary embolism or arterial/venous thrombosis cannot receive tamoxifen. Certain antidepressants are contraindicated in combination with this treatment. Consumption of grapefruit or blood oranges is contraindicated while taking an aromatase inhibitor..


Pour toute information complémentaire ou demande de rendez-vous, vous pouvez prendre contact avec  une Coordinatrice de Soins en Oncologie de la Clinique du Sein au  +32 2 764 42 27