HLA-Mismatched Stem Cell Microtransplantation Compared to Matched-Sibling Donor Transplantation for Acute Myeloid Leukemia in First Complete Remission

HLA-mismatched stem cell microtransplantation is a new transplantation which has been reported in recent years. We treated 41 patients with intermediate- or high-risk acute myelogenous leukemia (AML) in first complete remission (CR1) undergoing HLA-mismatched stem cell microtransplantation and compared with 56 patients undergoing HLA-matched sibling donor (MSD) transplantation at the same period in our center from July 2012 to August 2015. The estimated leukemia-free survival (LFS) at 2-year was 65.6% ± 9.5% in the MSD group and 27.6% ± 14.0% in the microtransplantation group (P = 0.011). The estimated overall survival (OS) at 2-year was 73.6% ± 8.6% in the MSD group and 46.2% ± 15.6% in the microtransplantation group (P = 0.056). The cumulative incidences of relapse were 22.5% and 58.7% among MSD and microtransplantation groups (P = 0.011). The cumulative incidence of nonrelapse mortality was 7.8% in MSD group, and no nonrelapse mortality in microtransplantation group (P = 0.265). Hematopoietic recovery time was shorter in the microtransplantation group than MSD group (P < 0.05). The infection rate of MSD group was higher than in the microtransplantation group (91.1% vs 75.6%, P = 0.037). The preliminary results suggest that LFS of microtransplantation is inferior to MSD transplantation and a trend toward the OS of microtransplantation was lower than MSD transplantation for intermediate- or high-risk AML in CR1.