Is Tamoxifen Prophylaxis Effective in Reducing the Incidence of Breast Cancer in Women Who Are at High Risk

OBJECTIVE: The objective of this EBM review is to determine whether or not Tamoxifen prophylaxis is effective in reducing the incidence of breast cancer in woman who are at high risk. STUDY DESIGN: Review of three English language primary studies published from 2005 to 2007. DATA SOURCE: Three double-blind randomized control trials found using the PubMed and Cochrane database. OUTCOME MEASURED: The primary outcome by all three studies included incidence of breast cancer. RESULTS: Three doubleblind randomized controlled trials were included in this review. Study by Powles et al showed statistically significant reduction in the incidents of breast cancer in the tamoxifen arm compared to placebo group. The second study by Cuzick et al showed the risk reducing effect of tamoxifen appears to persist for at least 10 years. The third study by Fisher et al showed the rate of invasive breast cancer was reduced from 42.5 per 1000 women in the placebo group to 24.8 per 1000 in the tamoxifen group. CONCLUSION: The result of three RTC’s showed that use of tamoxifen prophylaxis for breast cancer provides risk-reducing effect in women at high risk.