The expanding frontier of hematopoietic cell transplantation

Over the past several decades there has been a tremendous expansion of the indications for hematopoietic cell transplantation. This growth has been possible because of advances in supportive care, more effective graft versus host disease prophylaxis and the advent of reduced intensity conditioning regimens which have greatly reduced transplant related morbidity and allowed for the transplantation of older patients and patients with significant co-morbid disease. The role of flow cytometry in transplantation is crucial to both clinical care, for accuracy of diagnosis and monitoring of disease, and research. In this review, we highlight some of the important advances that have been made in the field, including the use of alternative donors for transplantation, novel therapies for the myeloid malignancies, which remain the prototype diseases for transplantation, and advances in diagnosis and treatment of graft versus host disease, which is the principal complication of allogeneic hematopoietic cell transplantation. Future directions in hematopoietic cell transplantation, particularly those that attempt to modulate the post-transplant cellular environment to favor separation of graft versus host disease from the graft versus tumor effects of the transplant are discussed.