Twenty patients with metastatic malignant melanoma were treated with melphalan (180-225 mg/m2 iv over 3 days) followed by re-infusion of previously harvested and cryopreserved autologous bone marrow. Granulocyte (greater than 500/microliter) and platelet (greater than 20,000/microliter) count recovery occurred a median of 14 days (range, 12-22) and 19.0 days (range, 12-28) after bone marrow transplantation, respectively. Three patients died due to hemorrhage or infection. One of these patients and another (who ultimately achieved a complete response), both with brain metastases, developed intralesional hemorrhage when the platelet count was only moderately reduced. Complete responses occurred in six patients and ranged from 4 to 14 months, with a median of 5 months. Six patients achieved a partial remission lasting 2-5 months. High-dose melphalan and autologous bone marrow transplantation are a promising therapy for patients with metastatic malignant melanoma.