Unrelated donor umbilical cord blood transplantation for the treatment of hematologic malignancies

Purpose of review This review summarizes the state of the art of unrelated donor (URD) umbilical cord blood transplantation (UCBT) for the treatment of hematologic malignancies and discusses the current issues associated with the use of this hematopoetic stem cell (HSC) source. Recent findings In contrast to the very high transplant-related mortality associated with the early experience of UCBT, recent series have been associated with comparable survival to that of human leucocyte antigen-matched URD transplantation in children with similarly promising results in adults with the use of double-unit grafts. In addition, utilization of reduced-intensity conditioning regimens has been successful extending access to patients unsuitable for myeloablation. Consequently, the use of umbilical cord blood as a HSC source and the global inventory of units in public banks is rapidly increasing although challenges associated with engraftment, unit quality, and infectious complications remain and will be discussed in this review. Summary URD umbilical cord blood is an alternative HSC source offering a unique set of advantages and disadvantages as compared with the transplantation of HSC from unrelated volunteers. Improved transplant outcomes are now making UCBT a rival to URD transplantation for the treatment of hematologic malignancies.