Nine patients with metastatic seminoma who had received no prior chemotherapy were induced with a combination containing cis-platinum 120 mg/m2 i.v. and cyclophosphamide 600 mg/m2 i.v. for 3-6 treatments at 4-6 wk intervals, and then received maintenance with cyclophosphamide 600 mg/m2 i.v. every 3-4 wk to complete 2 yr of chemotherapy. Eight patients entered complete remission (CR), 5 with chemotherapy alone and 3 with chemotherapy and radiation or resection of residual disease. Seven patients remain in CR with a minimum follow up of 17 mo. Chemotherapy is effective in treatment of metastatic seminoma.