Selective oestrogen receptor modifiers (SERMs) and breast cancer therapy

Antioestrogen therapy is currently receiving renewed interest for several r easons. Tamoxifen was introduced in the treatment of metastatic breast canc er more than three decades ago. The drug significantly reduces long term mo rtality and also reduces the risk of contralateral tumours when administere d in early breast cancel: Five years of tamoxifen is now standard in adjuva nt endocrine therapy, and the drug is currently being evaluated for breast cancer prevention. Despite this, several aspects regarding the pharmacology of the drug are still unclear; and the scientific rationale for dose selec tion has recently been challenged. Several novel antioestrogen compounds, c alled selective oestrogen receptor modifiers (SERMs), express selective oes trogen agonistic or antagonistic properties depending on the organ or test system evaluated. Some of these drugs, like raloxifene, do not seem to prom ote the development of endometrial cancer although they still have selected oestrogen-like beneficial effects. This paper reviews the pharmacologic an d the pharmacokinetic aspects of the different SERMs with particular emphas is on their potential use in therapy and prevention of breast cancer.