Paucity of HLA-identical unrelated donors for African-Americans with hematologic malignancies: The need for new donor options

Identification of an HLA identical donor/recipient pair using high-resolution techniques at HLA A, B, C, and DRB1 optimizes survival after adult unrelated hematopoietic stem cell transplant. It has been estimated that roughly 50% of African-Americans have suitable unrelated donors based on serologic typing, but there is little information on the likelihood of identifying an HLA-identical unrelated donor using molecular techniques. From February 2002 to May 2007, we performed 51 unrelated donor searches for African-American patients using the National Marrow Donor Program(R) and found HLA identical unrelated donors for only 3. By contrast, 50 (98%) had at least 1, and often multiple, appropriately matched cord blood units available. Very few African-American recipients have HLA-identical unrelated donors. To allow more African-American patients to proceed to transplant, innovative donor strategies, including adult cord blood transplantation, haploidentical transplant, or the identification of permissive mismatches should be investigated. (C) 2008 American Socicty for Blood and Marrow Transplantation.