[Role of adjuvant chemotherapy in the choice of chemotherapeutic treatment of metastatic breast cancer].

Adjuvant treatment of early breast cancer has changed considerably in recent years, and the majority of patients are currently treated with the most active single agents in this setting. As a result, the decisions regarding the treatment of patients with metastatic breast cancer have become more difficult. In patients who have not received chemotherapy for early-stage breast cancer or were treated with CMF, many choices are available, including regimens containing anthracyclines or taxanes. Patients who received anthracyclines in the adjuvant setting, may sometimes be re-treated with these agents, and the inclusion of a taxane is frequently the most reasonable choice. Among taxanes, docetaxel should be preferred because it is the most active single agent, and has a synergistic action with several other drugs, when used in combination. Taxanes can be used also in selected patients who had received these agents as adjuvant treatment. In particular, docetaxel did not show complete cross-resistance with paclitaxel, whereas weekly paclitaxel is only minimally effective in patients resistant to docetaxel. Retreatment with trastuzumab combined with chemotherapeutic agents might be a reasonable option in patients who had received adjuvant chemotherapy with trastuzumab. Nevertheless, another recent option is the combination of chemotherapy with lapatinib. Currently, novel target agents are being developed, with the potential to improve survival in patients with metastatic breast cancer. Arguably, the future for treatment of these patients appears to be the combination of effective single agents, such as docetaxel, with novel biologic therapies.