Role of stem cell transplantation.

Hematopoietic stem cell transplantation (SCT) was introduced in the treatment of multiple myeloma in the 1980s. In the autologous setting, the use of peripheral blood stem cells instead of bone marrow has markedly improved feasibility. In fit patients who have normal renal function and are younger than 65 years of age, randomized studies have shown the superiority of autologous stem cell transplantation (ASCT) compared with conventional chemotherapy. ASCT is now considered the standard of care in this population of patients. It is currently challenged, however, by the introduction of novel agents, such as thalidomide, bortezomib, and lenalidomide. The role of allogenic SCT remains controversial, even with reduced intensity conditionings. Prospective studies still are needed to evaluate the impact of both autologous and allogeneic SCT in this new era.