Prevention of breast cancer by newer SERMs in the future

The selective oestrogen receptor modulators (SERMs) tamoxifen has been shown to reduce the incidence of oestrogen receptor positive breast cancer by about 60 to 70% in healthy high risk women. The oestrogenic effects of tamoxifen caused a beneficial effect of reduced bone loss and fracture risk in postmenopausal women. However there was also significant gynaecological toxicity including an increased risk of endometrial cancer. Further clinical trials have evaluated the newer SERMs raloxifene, arzoxifene and lasofoxifene. The latter has been shown to significantly reduce the incidence of breast cancer, vertebral and non vertebral fractures, major coronary events and stroke with no significant gynaecological toxicity.