oestrogen receptors

oestrogen receptors

Chemical groups to which oestrogens bind and which are commonly found in substantial quantities on breast cancers. The oestrogen receptor status of a woman with breast cancer is important because the prognosis is much worse in women with high levels of oestrogen receptor alpha than in those with oestrogen alpha negative cancers. The status can easily and cheaply be determined by gene expression micro array analysis. 70 to 80 per cent of breast cancers are oestrogen receptor alpha positive. Tamoxifen, which has substantially reduced breast cancer mortality, is now regarded as an oestrogen receptor modulator.