Premenopausal women with hormone receptor–positive, HER2-negative disease and high recurrence risk may experience improvement of 10% to 15% in 5-year breast cancer-free interval (BCFI) with exemestane plus ovarian function suppression (OFS) versus tamoxifen alone. This according to a study of 4,891 women with hormone receptor–positive, HER2-negative breast cancer. Researchers found:
• In one clinical trial, patients who remained premenopausal after chemotherapy experienced absolute improvement of 5% or more in 5-year BCFI with exemestane plus OFS versus tamoxifen plus OFS or tamoxifen alone, reaching 10% to 15% at intermediate to high composite risk.
• The benefit of tamoxifen plus OFS versus tamoxifen alone was apparent at the highest composite risk.
• In another clinical trial, the benefit of exemestane plus OFS versus tamoxifen plus OFS in 5-year BCFI ranged from 5% to 15%.
• In both clinical trials, patients not receiving chemotherapy and with lowest composite risk did well with all endocrine therapies.
Citation: Regan MM, Francis PA, Pagani O, et al. Absolute benefit of adjuvant endocrine therapies for premenopausal women with hormone receptor–positive, human epidermal growth factor receptor 2–negative early breast cancer: TEXT and SOFT trials. [Published online ahead of print April 4, 2016]. Clin Oncol. doi:10.1200/JCO.2015.64.3171.