Chemoprevention of breast cancer.
Trials with tamoxifen have clearly shown that estrogen receptor-positive breast cancer risk can be reduced at a late stage in the natural history with prophylactic agents. Approximately half of the cases were prevented. The current challenge is to achieve this or better efficacy, and reduce side effects. A recent trial found that the selective estrogen receptor modulator raloxifene has similar efficacy to tamoxifen but fewer side effects. Long-term Phase III trials are currently underway studying two aromatase inhibitors. Results from other studies suggest that these agents have a better side-effect profile and may prevent 70-80% of receptor-positive breast cancers. New agents are needed for receptor-negative breast cancer and several possibilities are currently under investigation.
Cuzick
Jack
J
Cancer Research UK Centre for Epidemiology, Mathematics and Statistics, Wolfson Institute of Preventive Medicine, Barts and the London, Queen Mary's School of Medicine and Dentistry, Charterhouse Square, London EC1M 6BQ, UK. jack.cuzick@cancer.org.uk.