A team of researchers published their findings from a recent study, which began in March 2010, in The Lancet
. The group of 12 researchers explored the use of drugs in terms of breast cancer prevention strategies. Their published findings discuss the burden of breast cancer across the globe, as well as novel strategies for preventing the disease. Although there are many lifestyle factors that can stave off breast cancer, such as physical activity and modest alcohol intake, the researchers focused on the role of drugs in preventing breast cancer.
The team acknowledged that while mutations do play a role in the development of breast cancer these anomalies are rare in the general population. The researchers also said that measures for improved risk assessment should to be made in order to improve therapy. One approach to more aptly target therapy is to identify the density of a patient’s breast tissue. Studies have shown that a density of more than 75% can result in a five-fold increase in the risk of developing breast cancer.
The drugs the researchers explored most thoroughly include tamoxifen, raloxifene, lasofoxifene, arzoxifene, and aromatase inhibitors. Tamoxifen has proven to be successful in terms of preventive measures and recent studies have shown that it reduces estrogen-receptor positive invasive breast cancer by 43%. However, studies have shown the drug not to be effective in estrogen-receptor negative cancer. Raloxifene has been shown to reduce all invasive breast cancers by 23%. One of the more successful drugs used is lasofoxifene. Studies have found that when taken at the highest daily dose, lasofoxifene reduced the risk of estrogen-receptor positive breast cancer by 81%. Arzoxifene shows promise in terms of preventing estrogen-receptor positive breast cancer, but there were negative side effects associated with the use of the drug. Aromatase inhibitors have proven to be effective as a preventive treatment by lowering the risk of estrogen-receptor positive tumors by up to 75%.
The researchers explained that the “traditional approach to licensing drug treatments is not appropriate for preventive treatments,” and that “the approach to regulating drugs for [preventive] usage needs to change.”
Cuzick J, DeCensi A, Arun B et al. Preventive therapy for breast cancer: a consensus statement. Lancet Oncol. 2011 March 25. doi:10.1016/S1470-2045(11)70030-4. [Epub ahead of print]