New approaches to transplantation in acute myelogenous leukemia.

Allogeneic hematopoietic stem cell transplantation (HSCT) is a curative therapeutic option for acute myelogenous leukemia (AML). This is due to the combined effect of chemo/radiation therapy and the immunologic graft-versus-leukemia effect. The field of HSCT has benefited from advances in a variety of "fronts," including our increasing ability to break the human leukocyte antigen barrier, which has led to greater access to transplantation. Furthermore, progress in the biologic, genetic, and pharmacologic arenas is creating a scenario where traditional borders between transplant and non-transplant therapies are less clear. This overlap is exemplified by new approaches to pharmacologic maintenance of remission strategies after HSCT. In addition, cellular adoptive immunotherapy has the potential to exploit narrowly targeted anti-tumor effects within or outside the allogeneic HSCT "frame," holding the promise of avoiding off target side effects, such as graft-versus-host disease. Here we discuss these and other lines of active investigation designed to improve outcomes of HSCT for AML.