Optimal adjuvant endocrine therapy for breast cancer.

Abstract

Adjuvant endocrine therapy is the principal systemic treatment for non-metastatic hormone receptor-positive breast cancer. Incorporation of an aromatase inhibitor is superior to tamoxifen alone for postmenopausal women.1 Guidelines recommend aromatase inhibitor either upfront or as part of an early switch strategy after 2–3 years of tamoxifen.2 Recommendations on extended adjuvant endocrine therapy after 5 years are evolving. A randomised trial3 of extended adjuvant tamoxifen showed a survival benefit, but results from trials2,4,5 evaluating extended aromatase inhibitor therapy have been mixed and the optimal duration or type of endocrine therapy remains uncertain.