Tamoxifen offers long-term benefits in preventing breast cancer in women at high risk of the disease, according to updated findings of two large randomized placebo-controlled trials.
An international team of researchers conducting the International Breast Cancer Intervention Study found about 8 years after enrollment (and 3 years after the women stopped taking tamoxifen), women who had taken the drug had a statistically significant reduction in the incidence of estrogen receptor-positive breast tumors. The results “provide the first randomized evidence that the benefits of tamoxifen extend beyond the active treatment period, but the side effects [higher rates of deep vein thrombosis and pulmonary embolism] largely do not,” the researchers noted (Cuzick J et al. J Natl Cancer Inst. 2007;99:272-282).
Stephenson J. Reducing Breast Cancer Risk. JAMA. 2007;297(11):1182. doi:10.1001/jama.297.11.1182-d