Emerging data on endocrine therapies necessitates a re-evaluation of treatment strategies for advanced breast cancer. In this review, we present data from recent studies of the third-generation, nonsteroidal aromatase inhibitor (AI) anastrozole that illustrate its changing role in the treatment of postmenopausual women with advanced breast cancer. These studies demonstrate that anastrozole is now a treatment of choice as first-line therapy for patients presenting with advanced breast cancer and for patients who have progressed to advanced disease after adjuvant therapy with tamoxifen. A further trial has also shown that anastrozole is an effective and well-tolerated alternative to tamoxifen as adjuvant treatment for postmenopausal women with early breast cancer.
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