High-dose chemotherapy in resistant breast cancer

High-dose chemotherapy produces higher raters of complete and overall response in patients with metastatic breast cancer than does more conventionally dosed chemotherapy. In patients with breast cancer which had relapsed following, or was refractory to prior conventionally dosed treatment, complete remission rates of approximately 20-30% have been reported. Virtually all of these complete remissions are of relatively brief duration. As this modality is expensive, and is also associated with prominent clinical toxicity, these relatively frequent short-lived responses are not felt to justify routine use in the setting of resistant disease. Most interest in high-dose chemotherapy in metastatic breast cancer is now focused on patients with cancer who have responded to prior conventionally dosed chemotherapy, and increasingly on newly diagnosed patients with metastases. In these settings, single-cycle high-dose chemotherapy has been reported to produce durable complete remisions in 10-20% of patients. Newer investigational aspects of high-dose therapy include the application of multiple, rapidly cycled courses and the use of biological response modifiers. If these approaches were shown to enhance the anti-tumour activity of this modality substantially, it might be reasonable to resume investigation of high-dose therapy in patients with resistant disease.