It is a treatment which inhibits the formation or action of the hormone which feeds some types of tumour cells.
 
The cells of these tumours have receptors (proteins) which attach to hormones such as oestrogen or progesterone and depend on them to grow. These drugs either block this union or decrease the body’s hormone levels.
 
The tumour is destroyed or reduced, improving survival and quality of life.

Hormone-dependent tumours which depend on hormones for growth are usually:
 

• Breast cancer
• Prostate cancer

 
Other cancers such as those of the endometrium or ovary, or neuroendocrine tumours can also be treated with hormone therapy.
 
Usually we need to find out if the cancer cells have hormone receptors, to do this a biopsy (extraction of a piece of tumour) is required. If the specimen presents these receptors, then this treatment may work.

It can be given:
 

• APrior to surgery (as neoadjuvant therapy),
  with the aim of reducing the size of the tumour to enable its removal. This treatment often lasts 3-6 months prior to surgery.

 

• After surgery or radiotherapy (adjuvant therapy)
  to reduce the risk of recurrence. Treatment duration is often 5 to 10 years.

 

• Treatment of disseminated disease,
  to control symptoms or prevent disease progression. Treatment duration depends on the progression of the disease and how well it responds to treatment.

Women’s hormones change throughout their life, the amount and origin of oestrogen varies depending on the stage of a woman’s reproductive life.
 

In premenopausal women:
 
The amount of oestrogen is high and is generally produced by the ovaries.
 

Treatment:

Antioestrogens:
 

• They impede the union of oestrogens and oestrogen receptors (ER) in the cancer cells.

 

• They inhibit the growth of the tumour.

In post-menopausal women:
 
Oestrogen is lower, produced by the adrenal glands and body fat due to the action of an enzyme called aromatase.

Treatment:

Aromatase inhibitors:
 

• Impede the production of oestrogens through aromatase, reducing levels in the blood.

 

• Oral administration.

The aim is to reduce the number of male hormones (androgens) which help cancer cells to grow.
 
Themajority of prostate cancers present androgen receptors.
 
Androgens are mainly produced in the testicles in the form of testosterone, and in a small part in the adrenal glands.