Oncology Times Broadcast News For Early Breast Cancer, Switch to Aromatase Inhibitor after Tamoxifen Extends Survival Charles Coombes at ECCO15-ESMO34 on the Intergroup Exemestane Study showing a big increase in survival for patients with early breast cancer randomized to have their adjuvant therapy switched to exemestane after 2-3 years of tamoxifen, compared with those who remained on tamoxifen for the entire 5 years of endocrine therapy.