Raloxifene: a review of its use in the prevention of invasive breast cancer.

Raloxifene (Evista) is a second-generation selective estrogen receptor modulator (SERM) that functions as an estrogen antagonist on breast and uterine tissues, and an estrogen agonist on bone. It is available in many countries worldwide for the treatment and prevention of osteoporosis in postmenopausal women, and has also been approved in the US for reducing the risk of invasive breast cancer in postmenopausal women with osteoporosis or postmenopausal women at increased risk of invasive breast cancer.Raloxifene reduces the risk of invasive breast cancer in postmenopausal women at high risk of invasive breast cancer and in postmenopausal women with osteoporosis. In addition, it is a well established agent for the prevention and treatment of osteoporosis. There was no significant difference between raloxifene and tamoxifen in the reduction in the risk of invasive breast cancer achieved in postmenopausal women at high risk of such cancer. Raloxifene was associated with an increased, albeit rare, risk of venous thromboembolism across several placebo-controlled trials and an increased risk of fatal stroke in one placebo-controlled trial in postmenopausal woman at increased risk for major coronary events. However, raloxifene was associated with a lower risk of venous thromboembolic events and cataracts than tamoxifen in a head-to-head trial. The choice of chemoprevention agent must consider a risk-benefit assessment for each individual patient. In this context, raloxifene is a valuable option for the prevention of invasive breast cancer in postmenopausal women with osteoporosis or at high risk of invasive breast cancer.