Trastuzumab/chemotherapy combinations in metastatic breast cancer.

The past decade has seen many advances in the treatment of advanced breast cancer, including the development of both new chemotherapy drugs and novel targeted agents. Trastuzumab, a humanized monoclonal antibody directed against the HER2/neu protein, has been shown to be an efficacious treatment for HER2-overexpressing metastatic breast cancer, both as a single agent and when used in combination with chemotherapy. The US Food and Drug Administration has approved the use of trastuzumab and paclitaxel as first-line treatment of HER2-overexpressing metastatic breast cancer, based on the results of a randomized phase III clinical trial showing that this combination produced higher response rates and longer survival duration than treatment with chemotherapy alone. Further trials are currently underway evaluating the use of trastuzumab in combination with other forms of chemotherapy, including vinorelbine, docetaxel, anthracyclines, and platinum agents. Hopefully, information from these trials will help resolve questions regarding the efficacy of various combinations and dosing schedules so that trastuzumab may be used most effectively in the treatment of HER2-overexpressing breast cancer in both the metastatic and the adjuvant settings.