Impact of sex incompatibility on the outcome of single-unit cord blood transplantation for adult patients with hematological malignancies

Donor-recipient sex incompatibility has been associated with transplant outcomes in allogeneic hematopoietic SCT. Such outcomes might be because mHA encoded by Y chromosome genes could be immunological targets for allogeneic T cells and B cells to induce GVHD, GVL effect and graft failure. However, its effect on the outcome of cord blood transplantation (CBT) is yet to be clarified. We retrospectively analyzed 191 adult patients who received single-unit CBT after myeloablative conditioning for malignant disease in our institute. In multivariate analysis, male recipients with female donors had a higher incidence of extensive chronic GVHD (hazard ratio (HR) 2.97, P=0.02), and female recipients with male donors had a lower incidence of platelet engraftment (HR 0.56, P=0.02) compared with female recipients with female donors as the reference. Nevertheless, there was no increase in mortality following sex-incompatible CBT. These data suggested that donor-recipient sex compatibility does not have a significant impact on survival after myeloablative CBT for hematological malignancies.