Stem Cell Transplantation from a Haploidentical Donor Versus a Genoidentical Sister for Adult Male Patients with Acute Myelogenous Leukemia in First Remission: A Retrospective Study from the Acute Leukemia Working Party of the European Society For...

Background: In adult patients with acute myeloid leukemia (AML), a matched sibling donor (MSD) is considered the first choice for an allogeneic transplantation. However, a female donor for a male recipient is a poor prognostic factor. The authors compared haploidentical (HAPLO) donors with female MSDs.

Methods: In total, 834 men underwent allogenic transplantation from a female MSD, and 232 men underwent allogenic transplantation from a HAPLO donor. Of these, 86% of HAPLO recipients and 3% of MSD recipients received graft-versus-host disease (GVHD) prophylaxis posttransplantation with high-dose cyclophosphamide. A significant qualitative interaction was observed between donor type and cytogenetics, Therefore, the analyses were stratified on cytogenetics.

Results: Of the men with intermediate-risk AML, 638 received transplantation from a female MSD, and 160 received transplantation from a HAPLO donor. In multivariate analysis, poor risk factors were a HAPLO donor versus an MSD for nonrelapse mortality (hazard ratio [HR], 1.7; P = .02) and patient age for nonrelapse mortality and overall survival (HR, 1.22 [P = .02] and 1.15 [P = .02], respectively). HAPLO transplantation resulted in less chronic GVHD (HR, 0.43; P < 10 ) but lower leukemia-free survival (HR, 1.7; P = .04). The GVHD/relapse-free survival (GRFS) was not different. Of the men with high-risk AML, 196 received transplantation from a female MSD, and 72 received transplantation from a HAPLO donor. By multivariate analysis, HAPLO recipients had a lower incidence of relapse (HR, 0.40; P = .004), better leukemia-free survival (HR, 0.46; P = .003), better overall survival (HR, 0.43; P = .003), and better GRFS (HR, 0.54; P = .006).

Conclusions: In men who have intermediate-risk AML, allogenic transplantation from a sister MSD or a HAPLO donor produces similar GRFS. However, in men who have high-risk AML, a HAPLO donor combined with prophylactic high-dose cyclophosphamide posttransplantation may be a better choice.