Metastatic breast cancer.

Tamoxifen as adjuvant systemic treatment after first isolated locoregional recurrence of breast cancer has been shown to decrease the subsequent locoregional relapse rate, but it affects neither distant metastases nor survival. In metastatic disease, tamoxifen has not improved response when added to ablation of ovarian function. The cyclical sequential use of tamoxifen with megestrol acetate has not increased the response over tamoxifen alone. Aromatase inhibitors are an expanding field; formestane and vorozole are effective agents, and letrozole shows promise. In chemotherapy, major interest has focused on the use of taxoids, with high activity being reported for both paclitaxel and docetaxel, the latter being particularly effective as a second-line treatment. Reports continue to reaffirm the effectiveness of vinorelbine. The in vitro ability of quinidine to reverse resistance to anthracyclines has not been repeatable in a clinical setting. The evaluation of high-dose chemotherapy with bone marrow support continues to be explored, but this approach has thus far not been demonstrated to improve clinical outcome in advanced disease. The intra-arterial administration of chemotherapy appears to have a useful palliative role in selected patients with locoregional disease.