High-dose chemotherapy with BCNU, melphalan, or both, followed by autologous bone marrow transplantation (ABMT) has been reported to produce response rates in excess of 60% in patients with advanced melanoma. We tested doses of BCNU associated with reversible bone marrow toxicity and acceptable extramedullary toxicity without the use of ABMT in 19 patients with a diagnosis of advanced malignant melanoma. All patients were evaluable for toxicity and 18 were evaluable for response; one patient had a new primary tumor. The patient population had a median age of 44 years (range, 16 to 71) and a median Karnofsky performance status of 80 (range, 50 to 100). Ten were women and nine were men, all had visceral dominant disease, and none had received previous chemotherapy. Our purpose was to test the feasibility of treatment without ABMT, its toxicity and efficacy, and the possibility of administering sequential repeated courses of therapy. Vincristine was added to the regimen to potentially increase efficacy. Treatment consisted of BCNU (750 mg/m2) and vincristine (2 mg days 1 and 8). Six patients who recovered bone marrow function received melphalan (60 mg/m2) and vincristine (2 mg days 1 and 8). Twenty-two percent (95% confidence limits, 3% to 39%) of patients had remissions (all partial) and these were of short duration. Toxicity was substantial with 16% early lethality and 29% incidence of lethal drug-related complications. Two patients (11%) died toxic after a second course of BCNU. Our results suggest that there is no practical role for high-dose BCNU in the treatment of melanoma.