BCC 2021 | Tamoxifen reduced breast cancer risk in chest-irradiated cancer survivors

Judy Garber, MD, MPH, Dana-Farber Cancer Institute, Boston, MA, shares the findings of a Phase II randomized study (NCT01196936) of low-dose tamoxifen in chest-irradiated cancer survivors. Women who underwent therapeutic radiation in childhood or early adulthood are at increased risk of breast cancer development, comparable to the risk associated with germline BRCA mutations. To investigate risk-reduction capacity, 5mg/day tamoxifen was trialed against placebo in 72 participants with a history of chest irradiation. The results showed that tamoxifen use was safe, with no grade 3 or 4 adverse events, and significantly lowered mammographic dense area and IGF1 levels compared to placebo. The changes in these biomarkers of breast cancer risk suggest tamoxifen could be a promising prevention strategy. This interview took place during the 17th St. Gallen International Breast Cancer Conference.