Autologous/reduced-intensity allogeneic stem cell transplantation versus autologous transplantation in multiple myeloma: long-term results of the EBMT-NMAM2000 study

Long-term follow up of prospective studies comparing allogeneic transplantation to autologous transplantation in multiple myeloma are few and controversial. This is an update at a median follow up of 96 months of the EBMT NMAM2000 myeloma study that prospectively compares tandem autologous/reduced intensity conditioning allogeneic transplantation (auto/RICallo) to autologous transplantation alone (auto). 357 myeloma patients up to the age of 69 years were enrolled. Patients with an HLA-identical sibling were allocated to auto/RICallo (n=108) and those without to auto alone (n=249). At 96 months progression-free survival (PFS) and overall survival (OS) were 22% and 49% versus 12% (p=0.027) and 36 % (p=0.030) with auto/RICallo and auto respectively. The corresponding relapse/progression rate (RL) was 60% versus 82% (p=0.0002). Non-relapse mortality at 36 months was 13% versus 3% (p=0.0004). In patients with the del(13) abnormality corresponding PFS and OS were 21% and 47% versus 5% (p=0.026), and 31% (p= 0.154). Long-term outcome in patients with multiple myeloma was better with auto/RICallo as compared to auto only and the auto/RICallo approach seemed to overcome the poor prognostic impact of del(13) observed after autologous transplantation. Follow up longer than 5 years is necessary for correct interpretation of the value of auto/RICallo in multiple myeloma.