Extended therapy with letrozole as adjuvant treatment for postmenopausal HR-positive breast cancer

A standard adjuvant therapy for HR-positive breast cancer in postmenopausal patients is 2-3 years tamoxifen followed by 2-3 years of letrozole. A phase 3-study in Italy included patients after 2-3 years tamoxifen and randomized them to 2-3 years of letrozole versus 5 years of letrozole. The 12-years invasive disease-free survival rate was 62% in the 2-3 years group versus 67% in the 5 years group. The authors conclude that sequential endocrine therapy with tamoxifen for 2-3 years followed by letrozole for 5 years should be considered as one of the optimal standard endocrine treatments fo postmenopausal HR-positive breast cancer.