Although improvements in breast cancer management have been made, many women are diagnosed with metastatic breast cancer, an incurable stage of the disease. Several new therapies have become available over the past years that have changed the way we manage metastatic breast cancer. The new aromatase inhibitors, anastrozole, letrozole, and exemestane, are potent agents in this fight. Anastrozole and letrozole have been shown to produce superior efficacy and tolerability compared with tamoxifen as first-line endocrine therapy for metastatic breast cancer. Exemestane is being compared with tamoxifen in a similar manner, but results are pending. Trastuzumab is a monoclonal antibody directed against the HER2 oncogene with intrinsic antitumor activity and synergistic activity with traditional chemotherapy. Newer combinations with trastuzumab are also changing the way we administer other chemotherapy agents in patients who overexpress this oncogene. Traditional chemotherapy has also changed over the recent past and now includes an oral agent, capecitabine, for the treatment of metastatic breast cancer. Epirubicin, an anthracycline new to the United States, appears to have similar efficacy and toxicity to doxorubicin, with dosing issues being quite important. With all of these new agents within our grasp, there is hope for all patients with metastatic breast cancer.
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