The current status of aromatase inhibitors in the management of breast cancer

The third generation of specific aromatase inhibitors (AIs) - anastrozole, letrozole and exemestane, which reduce the biosynthesis of estrogen-have made an exciting contribution to the management of hormone-responsive breast cancer. Their role in advanced breast cancer has overtaken that of tamoxifen, which should be relegated to a second-line treatment. Anastrozole has proven superior to tamoxifen with respect to disease-free survival, time to recurrence, incidence of contralateral breast primary tumors as first events, and a number of important tolerability parameters. In treatment of postmenopausal advanced breast cancer the AIs should be considered for the first option, and in the adjuvant setting anastrozole now offers a choice for postmenopausal patients with hormone-responsive tumors, although longer follow-up will enable a more definitive benefit/risk assessment.