Adjuvant endocrine therapy in postmenopausal breast cancer patients

Tamoxifen has been the endocrine agent of choice for adjuvant hormonal therapy for early breast cancer since approval in 1986. Five years of tamoxifen treatment produced a significant reduction in recurrence and death over more than 10 years of follow-up in women with estrogen receptor-positive (ER+) breast cancer. In large randomised trials, the standard of 5 years tamoxifen has been challenged by third-generation aromatase inhibitors (AIs) in the adjuvant setting. This review provides a synopsis of the most recent trial results and a discussion of remaining areas of uncertainties. Although currently tamoxifen still remains a valid option, increasing evidence from the new AI adjuvant trials suggests that optimised adjuvant endocrine treatment should incorporate an AI either as initial or as sequential therapy.