Tamoxifen is an anti-estrogen used for both the treatment and prevention of breast cancer. The side effects of tamoxifen have been extensively debated over the past two decades. The National Surgical Adjuvant Breast and Bowel Project (NSABP) P-1 study recently demonstrated that tamoxifen prevents breast cancer leading to FDA approval in certain high-risk patients. As part of the NSABP study, the health-related quality of life effects potentially attributable to tamoxifen were also evaluated.
The NSABP P-1 study was a randomized clinical trial involving 11,064 women. Half the women received tamoxifen and half received placebo. While the initial focus on side effects evaluated the risk of blood clots and uterine cancer in tamoxifen recipients, doctors also wanted to understand the likelihood of other side effects and their impact on a woman's quality of life.
The NSABP clinical study demonstrated that tamoxifen prevents the development of breast cancer in selected high-risk patients. This study found no differences in the incidence of depression, physical activity or mental problems in women receiving tamoxifen compared to placebo. Patients receiving tamoxifen, however, did have more vasomotor (flushing, palpitations, blood pressure changes) and gynecologic symptoms (sexual dysfunction) than patients receiving placebo.
The physicians conducting this study concluded that women need to be informed of the increased frequency of vasomotor and gynecologic symptoms associated with tamoxifen use. Weight gain and depression, two clinical problems often attributed to tamoxifen treatment, however, were not increased in frequency. (
Journal of Clinical Oncology, Vol 17, Issue 9, p 2659, 1999)