Microtransplantation Improves the Outcome of Older Patients With Newly Diagnosed Acute Myeloid Leukaemia: a Single-centre Study With Long-term Follow-up

Abstract Purpose: This retrospective single-centre study was to validate the efficacy and safety of microtransplantation (or micro-stem cell transplantation, MST) in the treatment of older patients with acute myeloid leukemia (AML).Methods: MST combines chemotherapy and human leukocyte antigen (HLA)-mismatched peripheral blood stem cell infusion without graft-versus-host disease (GVHD) prophylaxis. In total, 26 newly diagnosed AML patients were enrolled in our study from April 2008 to April 2018. The deadline date of follow-up was December 31, 2019. All of them received MST. Patients were divided into 2 age groups: 60~70 years (n=17) and >70 years (n=9). The outcomes of complete remission (CR) rate, overall survival (OS), leukemia free survival (LFS), hematopoietic recovery time, and treatment related toxicities were analyzed and summarized in this study.Results: 10 patients were still alive with complete remission (CR) at the deadline date, and the median overall survival (OS) was 64 months (range, 21-135 months). The CR, relapse and nonrelapse mortality rates were 84.6%, 38.5% and 30%, respectively. Both OS (p < 0.0001) and leukaemia free survival (LFS) (p < 0.0001) were significantly higher in the younger group than in the older group. The median times of neutrophil and platelet recovery were 12 days and 14 days, respectively. Conclusions: These data showed that MST could be an alternative treatment for older AML patients.