Hematopoietic Stem Cell Transplantation in Multiple Myeloma: A Retrospective Study of the Société Française de Greffe de Moelle et de Thérapie Cellulaire (SFGM-TC).

Because the indication of allograft (allogeneic stem cell transplantation [alloSCT]) for multiple myeloma (MM) has widened in recent years, thanks to the development of reduced-intensity conditionings (RIC), it is still unclear if myeloablative conditioning (MAC) remains appropriate. This study compares retrospectively outcomes of patients undergoing either RIC or MAC regimens for MM. Based on the SFGM-TC registry, we included 446 MM patients receiving alloSCT between 1999 and 2009 for whom a minimal data set was available. Median follow-up for the entire cohort was 33.6 months (range, 0 to 164.5). RIC and MAC populations were different regarding age (53.5 versus 47.1 years, respectively), number of prior autologous (auto)SCTs (93.2% versus 79.6% had at least 2 autoSCTs), and stem cell source (90.2% versus 61.2% received peripheral blood). For RIC and MAC populations the nonrelapse mortality at 2 years was 24.6% and 22.4%, respectively, progression-free survival 35.5% and 51.1%, and overall survival 59.5% and 66.7% (not significant). These outcomes were not affected by conditioning intensity either on univariate or multivariate analysis. Despite some limitations in the study design, these results indicate that MAC should remain a valuable option in alloSCT for MM, especially for young and less-treated patient with no comorbidity. The constant progress in induction treatments of MM and supportive care after alloSCT could improve these results in the near future.