Comparison of Autologous Stem Cell Transplantation versus Haploidentical Donor Stem Cell Transplantation for Favorable- and Intermediate-Risk Acute Myeloid Leukemia Patients in First Complete Remission

Abstract

Stem cell transplantation (SCT) is an attractive postremission treatment option for patients with intermediate-risk acute myeloid leukemia (AML) and for some favorable-risk AML patients with additional nongenetic risk factors. Autologous SCT (auto-SCT) and haploidentical donor SCT (haplo-SCT) are the widely used alternatives in cases of a lack of a HLA-matched donor. However, limited data have been published on the direct comparison between these 2 transplant types. Based on the transplant database in our center, we conducted a retrospective study involving patients with favorable- and intermediate-risk AML in first complete remission (CR1), according to the National Comprehensive Cancer Network guideline. Patients with extramedullary disease or those achieving CR by more than 2 cycles were excluded. In total, 195 patients were included in the study, 88 of whom underwent auto-SCT and 107 haplo-SCT. In the entire cohort analyses the impact of high relapse incidence in the auto-SCT group was compensated by low nonrelapse mortality (NRM), which resulted in a comparable overall survival (OS) (79.0% ± 4.6% versus 80.1% ± 5.0%, P = .769) and relapse-free survival (RFS) (66.1% ± 5.2% versus 77.4% ± 4.8%, P = .079) compared with those observed in the haplo-SCT group. However, for patients with intermediate-risk AML, NRM was similar between the groups, and haplo-SCT exhibited superior survival. In case of post-SCT relapse, patients with intermediate-risk AML showed markedly inferior 3-year OS compared with that shown by patients with favorable-risk AML (23.3% ± 9.8% versus 60.8% ± 14.3%, P = .011). In the multivariate analyses, minimal residual disease (MRD) measured by flow cytometry and gene mutation status before transplantation were independent predictors for both OS and RFS. We concluded that both auto-SCT and haplo-SCT were acceptable options for postremission treatment of patients with favorable- and intermediate-risk AML. Haplo-SCT yielded a better outcome in patients with intermediate-risk AML, but the relapse after SCT still led to a poor outcome. Clearance of MRD before SCT could improve the prognosis after transplantation.