Selection of adult unrelated hematopoietic stem cell donors: beyond HLA

HLA matching is the dominant controllable donor-recipient factor determining the outcome of adult unrelated donor hematopoietic cell transplantation. Beyond HLA, donor selection is often based on donor characteristics such as age, sex, parity, cytomegalovirus (CMV) serostatus, and ABO blood type. The published evidence to suggest these additional factors are important determinants of survival is weak and is sometimes conflicting. Other factors may be more important for optimal donor selection than the traditional non-HLA factors. These include the donor's geographic location, the performance history of the groups managing the donor, a priori knowledge of the donor's willingness/availability, and others. Implementation of tools to expose this additional donor-related information could significantly alter and aid unrelated donor selection practices.