Press Release: Chemotherapy, But Not Tamoxifen, Associated With Stroke Risk After Breast Cancer Treatment

Extract

Tamoxifen use for the treatment of breast cancer is not associated with an increased risk of stroke, according to a new study in the October 20 issue of the Journal of the National Cancer Institute. However, chemotherapy use is associated with an increased risk of stroke, regardless of tamoxifen use.

Tamoxifen has been used for the treatment of postmenopausal breast cancer since 1978. Since then, the drug has also been shown to reduce the risk of contralateral breast cancer and breast cancer recurrence and to halve the risk of breast cancer in women at high risk for the disease. However, tamoxifen use does have the potential for serious side effects. One of those side effects, an increased risk of stroke, was suggested in two large randomized trials but not in other studies.

To assess the impact of tamoxifen treatment for breast cancer on stroke risk, Ann M. Geiger, Ph.D., of Kaiser Permanente Southern California in Pasadena, and colleagues conducted a nested case–control study among women from Los Angeles County who were enrolled in a large health maintenance organization and were diagnosed with breast cancer between 1980 and 2000.