The adjuvant endocrine treatment revolution: focus on anastrozole.

Anastrozole is a nonsteroidal, third-generation aromatase inhibitor, which is heralded as an effective alternative endocrine therapy to tamoxifen in postmenopausal women with hormone-responsive breast cancer. Anastrozole has a high affinity for aromatase, a CYP enzyme involved in estrogen synthesis, and provides effective estrogen suppression with little, if any, impact on other CYP enzymes, lipid profiles or steroidogenesis. The use of anastrozole is now widely accepted in advanced breast cancer and its superior efficacy and tolerability to tamoxifen has recently been demonstrated in early breast cancer.