Maximizing clinical benefit with trastuzumab

To optimize patient management in breast cancer a number of factors are considered, including hormone receptor and HER2 status. A feasible approach for women with less aggressive, estrogen receptor/HER2-positive metastatic breast cancer is to consider trastuzumab (Herceptin; F. Hoffmann-La Roche, Basel, Switzerland) combined with endocrine therapy. Randomized clinical trials are ongoing to assess the combination of trastuzumab with aromatase inhibitors. In patients with aggressive HER2-positive metastatic breast cancer, trastuzumab/chemotherapy combination regimens are warranted. When administered first line in combination with a taxane, trastuzumab improves all clinical outcome parameters, including survival, in such patients. Trastuzumab adds little to the toxicity profile of taxanes, and trastuzumab combination therapy is associated with improvements in quality of life when compared with chemotherapy alone. There is encouraging evidence of improved efficacy when trastuzumab is combined with other cytotoxic agents with proven single-agent activity in breast cancer, including capecitabine (Xeloda; F. Hoffmann-La Roche), gemcitabine, and vinorelbine. Trastuzumab is also being investigated as part of triplet drug regimens. Trastuzumab has good single-agent activity in first-line therapy. This is of relevance to women with HER2-positive disease who are not suitable for, or do not wish to receive, cytotoxic chemotherapy. The benefits noted with trastuzumab-containing regimens were documented in clinical trials where trastuzumab was given until disease progression. A further rationale exists to continue trastuzumab beyond progression. Data from retrospective reviews indicate that this strategy is feasible.