We aimed to determine the benefits judged necessary to make adjuvant endocrine therapy worthwhile by women who participated in a large randomised clinical trial evaluating 2 years of adjuvant endocrine therapy with tamoxifen, goserelin, or both in women 50 years or younger with early breast cancers that expressed hormone receptors (the Under Fifties Trial) (Dellapasqua et al, 2005). This evidence concerns the gene NR4A1 and breast cancer.