Adjuvant Letrozole Continues to Best Tamoxifen for Early Breast Cancer

Letrozole monotherapy was better than tamoxifen monotherapy; sequential letrozole and tamoxifen were not better than letrozole alone.

To optimize adjuvant endocrine therapy for postmenopausal breast cancer, several randomized trials have been designed to evaluate aromatase inhibitors (AIs) compared with the traditional standard of tamoxifen for 5 years. Results generally have suggested that integrating an AI in some way confers incremental improvements in disease-free survival (DFS) over tamoxifen alone. BIG (Breast International Group) 1-98 is a seminal, industry-sponsored trial in which postmenopausal women with hormone receptor–positive early breast cancer were randomized among four treatment arms (JW Oncol Hematol Mar 12 2007):

Letrozole for 5 years (1546 women)
Tamoxifen for 5 years (1548 women)
Letrozole for 2 years, followed by tamoxifen for 3 years (1540 women)
Tamoxi…

Reviewing Author

William J. Gradishar, MD

Disclosures

Consultant/Advisory BoardLilly; AstraZeneca; Gilead

Grant/Research SupportBreast Cancer Research Foundation

Editorial BoardsClinical Breast Cancer; Oncology; Annals of Surgery; Breast Cancer Research and Treatment

Leadership Positions in Professional SocietiesNational Comprehensive Cancer Network (Chair, Breast Cancer Panel); American Board of Internal Medicine (Medical Oncology Board)