High-dose therapy and autologous blood stem-cell transplantation compared with conventional treatment in myeloma patients aged 55 to 65 years: long-term results of a randomized control trial from the Group Myelome-Autogreffe.

To study the impact of high-dose therapy (HDT) with autologous stem-cell support in patients with symptomatic multiple myeloma (MM) between the ages of 55 and 65 years. One hundred ninety patients between 55 and 65 years old who had newly diagnosed stage II or III MM were randomly assigned to receive either conventional chemotherapy (CCT; ie, monthly courses of a regimen of vincristine, melphalan, cyclophosphamide, and prednisone) or HDT and autologous blood stem-cell transplantation (using either melphalan alone 200 mg/m(2) intravenous [IV] or melphalan 140 mg/m(2) IV plus busulfan 16 mg/kg orally as pretransplantation cytoreduction). Within a median follow-up of 120 months, median event-free survival (EFS) times were 25 and 19 months in the HDT and CCT groups, respectively. Median overall survival (OS) time was 47.8 months in the HDT group compared with 47.6 months in the CCT group. A trend to better EFS (P = .07) was observed in favor of HDT, whereas OS curves were not statistically different (P = .91). The period of time without symptoms, treatment, and treatment toxicity (TwiSTT) was significantly longer for the HDT patients than for the CCT patients (P = .03). With a median follow-up time of approximately 10 years, this randomized trial confirmed a benefit of HDT in terms of EFS and TwiSTT but did not provide evidence for superiority of HDT over CCT in OS of patients aged 55 to 65 years with symptomatic newly diagnosed MM.