Abstract S3 08: Randomized comparison of adjuvant tamoxifen (T) plus ovarian function suppression (OFS) versus tamoxifen in premenopausal women with hormone receptor positive …

Background It is uncertain if the addition of OFS to adjuvant endocrine therapy with T improves outcomes in premenopausal HR+ BC. The SOFT trial was designed to determine the value of OFS in women who remain premenopausal and are treated with T (OFS question) and also to test whether an AI improves outcome in premenopausal women with HR+ BC treated with OFS (AI question). In the combined analysis of the TEXT and SOFT trials (AI question), the group treated with the AI exemestane+OFS had a significantly better disease-free survival (DFS) than those with T+OFS. This abstract presents the results of the OFS question (n=2,045).Patients and Methods Between November 2003 and January 2011, the SOFT phase 3 trial randomized 3066 premenopausal women with HR+ BC to 5 years of adjuvant endocrine therapy with exemestane+OFS versus T+OFS versus T alone, with OFS initiated by choice of …