Fifty-six patients with advanced metastatic carcinoma of the breast, melanoma and lymphoma were treated with the new vinca alkaloid vindesine in a prospective Phase II study. The dose was 3 mg/M2 by I.V. bolus once a week for a minimum of two doses. Patients who failed to respond to four I.V. doses were treated with 48-h intravenous infusions at a dose of 1.5 mg/M2 per 24 h. Of the 26 evaluable patients with breast cancer, there were only two incomplete responses and four patients who experienced stabilization of disease. Of the 12 evaluable patients with melanoma, no responses were seen with four patients experiencing stabilization of disease. Of the 11 patients with non-Hodgkin's lymphomas, there was one complete remission which persisted for 26 months and two partial remissions. No additional responses were seen when the mode of administration was changed to 48-h infusion in three patients with breast cancer, five patients with melanoma and one patient with lymphoma. Significant toxicities included neutropenia in 24 patients and nausea and vomiting in two patients. There were no drug related deaths. Previously reported experience with vindesine in these tumors is reviewed as well.