Hormone (Endocrine) Therapy
Hormone therapy is the term used to describe any treatment, which uses the effects of hormones to control growth of cancer cells. This can mean removing hormones from the circulation (suppression) or adding them to the circulation. Cancer cells that require hormones for growth will be prevented from growing by removal of hormones from the system. Cancers of cells that produce hormones will not be stimulated to grow and produce hormones if there are plenty of the hormones in the body already e.g. thyroid cancer cells. Providing these hormones prevents cancer cell growth from being triggered by low levels of hormone.
Examples of hormone therapy
Some cancer cells only grow in the presence of hormones, for many with breast cancer the female sex hormone oestrogen is necessary to enable growth. Cutting off the supply of oestrogen to the tumour cells with drugs can prevent recurrent disease and prolong survival. Cutting off the oestrogen supply like this can have distressing side effects – e.g. causing an early menopause. Prostate cancer cell growth is dependent on the male sex hormone, testosterone. Growth can be controlled by suppressing or exaggerating the level of hormones in the body.
