Tamoxifen Prevents Breast Cancer in Some
Helps Women at High Risk for Hormone-Dependent Breast Cancer
While saying their findings must be confirmed in future studies, researcher Umberto Veronesi and colleagues conclude that hormone-related risk factors like the ones they identified could help target women who might benefit from tamoxifen. Estrogen-dependent breast cancer is the most common type.
"Such a strategy would greatly reduce the numbers of women who would need to take tamoxifen to obtain the same absolute reduction in breast cancer," they write.
Vogel tells WebMD that the study's definition of high risk does not include well-established risk factors such as a woman's age, her family history of breast cancer, number of breast biopsies, and whether she has atypical, pre-cancerous cells. Other common risk factors for breast cancer include, not having had children, early age of first period, and late menopause.
"One very important message is that every woman over 40 ought to discuss her level of risk with her physician," says Vogel, who directs the breast cancer prevention program at the University of Pittsburgh. "And the 15% to 20% of women who are truly at increased risk should be referred for a formal risk assessment to determine if they are candidates for preventive therapy."
Vogel says tamoxifen, while effective, is not the ideal drug for preventing breast cancer. The osteoporosis drug Evista may be just as effective without increasing the risk of uterine cancer. The two drugs are currently being compared in a study involving approximately 19,000 women at high risk for breast cancer, and findings are expected in about four years. And a new class of drugs, known as aromatase inhibitors, is also showing promise as a preventive treatment in early trials.
"It is a pretty safe bet that within the next few years, as the studies come in, preventive treatments will be safer and more effective," Vogel tells WebMD.