Cyclophosphamide (50 mg/kg) was administered intravenously over 1 hour daily for four consecutive days (200 mg/kg total) through a Hickman catheter. The dose of cyclophosphamide was based on the ideal body weight as determined by the Metropolitan Life tables.28 29 If the patient's actual weight was less than the ideal body weight, the actual body weight was used to calculate the cyclophosphamide dose. Intravenous mesna (10 mg/kg) was given 30 minutes before cyclophosphamide and then 3, 6 and 8 hours after cyclophosphamide was administered for prophylaxis against haemorrhagic cystitis. Intravenous ondansetron (32 mg) was administered 1 hour before each dose of cyclophosphamide. Six days after the last dose of cyclophosphamide, all patients received granulocyte colony-stimulating factor (5 µg/kg/day) until the neutrophil count was 1×109/l for two consecutive days. Prophylactic antibiotic support, consisting of fluconazole (400 mg/day), norfloxacin (400 mg/day), and valaciclovir (500 mg twice a day, if antibodies to herpes simplex were present), was given beginning the day after the last dose of cyclophosphamide and continuing until the neutrophil count exceeded 0.5×109/l. Dapsone (100 mg three times a week for 6 months) or trimethoprim-sulfamethoxazole (80/400 mg three times a week for 6 months) was administered for Pneumocystis carinii prophylaxis. Packed red blood cell (leucocyte-poor) transfusions were administered to maintain a haematocrit level >25%. Platelet transfusions were given for bleeding or to maintain a platelet count >10×109/l, or both. All blood products were irradiated (>2000 rad) to prevent graft versus host disease.