HIGH-DOSE CHEMOTHERAPY IN THE TREATMENT OF BREAST-CANCER

Dose is a critical determinant of the efficacy of chemotherapy. The do se response curve for virtually all anticancer agents is steep in both in vitro and in vivo experimental studies. However the application of the steep dose-response curve in the clinic has been troublesome for many years because of dose limiting bone marrow toxicity. Hematopoieti c support with growth factors and/or peripheral stem cell transplantat ion now offers new possibilities to push doses up to levels where non- myeloid toxicity becomes dose limiting. Several trials applying high d ose chemotherapy with stem cell support have been conducted in breast cancer. They showed a higher response rate and a higher percentage com plete remissions compared with conventional treatment. Follow-up is sh ort for most studies but some long-term complete remissions are report ed. Developments in this field are reviewed.