Exemestane in postmenopausal women with early or advanced breast cancer: a review.

IMPORTANCE OF THE FIELD: Inhibition of the aromatase enzyme in postmenopausal women reduces levels of estrogens, which is of therapeutic value in hormone-sensitive breast cancer. Exemestane is a third-generation steroidal irreversible inactivator of the aromatase enzyme used in early and advanced breast cancer for the treatment of postmenopausal women with estrogen-receptor-positive disease.

AREAS COVERED IN THIS REVIEW: The scientific literature on exemestane, including published articles and abstracts, was searched from 1988 to the present, and the most significant results are included in the review.

WHAT THE READER WILL GAIN: The review outlines the pharmacological characteristics of exemestane and the evidence supporting its use in the treatment of postmenopausal women with early or advanced estrogen-receptor-positive breast cancer.

TAKE HOME MESSAGE: Exemestane is an effective and well-tolerated aromatase inhibitor with a defined role in early-stage breast cancer following 2 - 3 years of adjuvant treatment with tamoxifen. Exemestane also has a role in the sequence of hormonal agents employed to control advanced hormone-sensitive breast cancer, in which clinicians may exploit its partial lack of cross-resistance with nonsteroidal aromatase inhibitors.