Who Is the Best Hematopoietic Stem-Cell Donor for a Male Patient With Acute Leukemia?

Background Female donors for male recipients worsen the outcome of allogeneic hematopoietic stem-cell transplantation. We wanted to find out whether a male human leukocyte antigen (HLA)-matched unrelated donor (MUD, 8/8, n=2,014) might be an alternative to a female HLA-identical sibling donor (n=2,656) for male patients with acute leukemia. Methods This is a retrospective analysis from the Acute Leukaemia Working Party of the European Group for Blood and Marrow Transplantation. Results The relative risk (RR) of acute graft-versus-host disease (GVHD) of grades II to IV was increased in the MUD group with acute myeloid leukemia (AML) (RR, 1.47; P<0.001) and acute lymphoblastic leukemia (ALL) (RR, 1.76; P<0.001). There was no difference in incidence of chronic GVHD and nonrelapse mortality between the two groups. Probability of relapse was lower in the MUD group than in the sibling group in patients with ALL (hazards ratio [HR], 0.75; P=0.04) but not in the AML patients (HR, 0.89; P=0.17). Survival was not different between the groups. Leukemia-free survival (LFS) was also similar in the sibling and MUD groups in patients with AML (HR, 1.01; P=0.81) or ALL (HR, 0.93; P=0.45). Factors significantly associated with reduced LFS included active disease, poor cytogenetics, age, year of hematopoietic stem-cell transplantation, reduced-intensity conditioning, and the use of antithymocyte globulin. Conclusion Male patients who received grafts from male MUDs demonstrated an increased incidence of acute GVHD and LFS same as when using HLA-identical female donors.