We were pleased to hear that chemoprevention as a means of breast cancer risk reduction is being seriously discussed. In a recent internal medicine meeting, Dr. Jennifer R. Diamond, a medical oncologist from the University of Colorado at Denver, spoke about the importance of chemoprevention as a primary means of reducing a woman s risk of breast cancer.
Chemoprevention, which is rarely employed by primary care physicians, is a way to prevent or delay cancer through various therapies. In the context of breast cancer, these therapies include estrogen receptor antagonists such as tamoxifen and raloxifene, which, among high risk premenopausal women, have been show to reduce the risk of disease by 50 percent. For postmenopausal women, aromatase inhibitors such as exemestane have also been shown to reduce risk.
Those eligible for primary chemoprevention have been identified by the National Comprehensive Cancer Network as women who have a first-degree relative with breast or ovarian cancer, a history of thoracic irradiation, mutations predisposed to breast cancer (especially the BRCA-1 and 2 mutations), or a five-year risk of breast cancer of at least 1.7 percent as determined by the breast cancer risk assessment tool.
Though an estimated 2 million premenopausal U.S. women are candidates for primary chemoprevention of breast cancer with tamoxifen, only 4 percent of them are currently on the drug.
As Dr. Diamond explains, there are different chemoprevention options available. High risk premenopausal women can benefit from five years of oral tamoxifen, while postmenopausal women should use exemestane (Aromasin) which, although a safer option, is currently used off-label for chemoprevention.
Nearly 230,000 American women will receive a breast cancer diagnosis in 2012, and more than 39,000 will die from the disease. Yet despite these daunting statistics, Dr. Diamond found that 93 percent of her polled audience was not comfortable with prescribing chemoprevention drugs. You ll find that many of your patients are candidates, Dr. Diamond maintained.
As for the drugs side effects, Dr. Diamond finds that they are quite minor, with hot flashes being the most common one cited. And when it comes to risks of venous thromboembolism or endometrial cancer, Dr. Diamond says that such consequences are incredibly uncommon in women under 50.
We applaud Dr. Diamond s efforts to make chemoprevention a standard approach in reducing the prevalence of breast cancer. As ACSH s Dr. Elizabeth Whelan notes, We here at ACSH have been advocating the more extensive knowledge of and use of chemoprevention drugs for over a decade now."