Back to the Future: Mismatched Unrelated Donor, Haploidentical Related Donor, or Unrelated Umbilical Cord Blood Transplantation?

Allogeneic stem cell transplantation is potentially curative for patients with hematologic malignancy. However, patients have only a 25% likelihood of HLA matching with a sibling and <1% chance of HLA matching with another relative. For patients without a suitably matched related donor, options include starting the search for an unrelated donor, cord blood units, or a partial family match. The chance of finding an "8 of 8 allele level," HLA-A, -B, -C, -DRB1 matched unrelated donor for Caucasian patients is 60% to 70%, but only 10% to 35% for U.S.