BUSULFAN AND MELPHALAN AS CONDITIONING REGIMEN FOR AUTOLOGOUS PERIPHERAL-BLOOD STEM-CELL TRANSPLANTATION IN MULTIPLE-MYELOMA

Twenty-four patients with multiple myeloma (MM), three (12.5%) in comp lete remission (CR) and 21 (87.5%) in partial remission (PR) were trea ted with high-dose chemotherapy (HDCT) (busulfan 12 mg/kg + melphalan 140mg/m(2)) as preparative regimen for autologous peripheral blood ste m cell (PBSC) transplantation. These cells were previously collected b y leukapheresis after mobilization by high-dose cyclophosphamide (HD C y) + rhGM-CSF (18 patients) or rhG-CSF alone (six patients). Consideri ng 23 evaluable patients following HDCT, the CR rate was 58% (14 patie nts) and the PR rate was 38% (nine patients). One transplant-related d eath occurred following this regimen (4%). With a median follow-up of 20 months (range 4-34) after transplantation, 21 patients are alive (8 7%). Disease progression after transplantation was observed in four pa tients. Overall and relapse-free actuarial survival at 24 months was 9 1% and 74%, respectively. 12 patients (50%) remain in CR 15 months (4- 34) post transplant. The major toxicity was mucositis. Busulfan + melp halan is a safe and feasible conditioning regimen for APBSCT in MM wit h acceptable toxicity and a high objective response rate, which may re sult in prolonged survival.