In the phase III, DATA study that was presented by Tjan-Heijnen el al, #extended_adjuvant endocrine therapy failed to improve the DFS or OS significantly in the adjuvant treatment of early #breast_cancer. DATA is a Dutch study that compared 3 versus 6 years of adjuvant #Anastrazole after initial 2-3 years of adjuvant #tamoxifen. Several studies have explored the impact of extended adjuvant endocrine therapy with conflicting results. Of note, one third of the population had node negative disease and three quarters had both ER and PR positive.