What are endocrine therapies?
Endocrine therapies are sometimes referred to as hormonal therapies – ‘endocrine’ is a word used to describe the natural hormones that are secreted from glands in the body and affect the structure or function of other cells in the body. Some breast cancers are encouraged to grow by the presence of hormones and in particular the natural female hormone oestrogen. The hormone oestrogen attaches itself to the surface of these cancer cells by receptors on the cell surface and these cancers are therefore called ‘oestrogen receptor-positive’ or ‘hormone receptor-positive’ cancers. Endocrine therapies stop or slow down the growth of these hormone receptor-positive breast cancers by interfering with either the ‘manufacture’ of oestrogen by the body or by blocking the uptake of oestrogen by the cancer cells. Only tumours that are hormone receptor-positive will respond to hormone therapy.
