Hematopoietic cell transplantation for congenital bone marrow failure

Abstract

Congenital bone marrow failure is rare and multifactorial. This review focuses on the outcome after allogeneic hematopoietic cell transplantation for the treatment of these disorders, with particular emphasis on recent discoveries and the challenges. In the treatment of congenital bone marrow failure disorders, the goals are to eliminate or reduce early and late toxicities and the risk of graft-versus-host disease. Novel nonmyeloablative fludarabine-based preparative regimens have demonstrated low risks of toxicity and acceptable engraftment rates for several congenital bone marrow failure disorders. Although there seems to be less early toxicity, longer follow-up is needed to determine late effects, especially the development of malignancy. T cell depletion of the bone marrow or peripheral blood, or the use of umbilical cord blood, has decreased the risk of graft-versus-host disease. Together, reduced toxicity and low rates of graft-versus-host disease have at least minimized the morbidity early after transplantation, with promising early survival. With marked improvement in rates of survival after allogeneic hematopoietic cell transplantation for selected congenital bone marrow failure disorders, emphasis is now being placed on improving quality of life and reducing late effects. Multicenter collaborative trials will determine the best treatment for these rare disorders.