[Efficacy and Safety of Cladribine-based Intensified Conditioning Regimen in Hematopoietic Stem Cell Transplantation in Patients with High-Risk Acute Myeloid Leukemia].

ABSTRACT

OBJECTIVE: To investigate the efficacy, safety and the risk factors affecting prognosis of high-risk acute myeloid leukemia (AML) patients treated by cladribine-based intensified conditioning regimen. METHODS: The clinical data of 28 patients with high-risk AML treated by cladribine in combination with busulfan plus cyclophosphamide (BuCy) intensified conditioning regimen before allogeneic hematopoietic stem cell transplantation (allo-HSCT) in Zhujiang Hospital, Southern Medical University from October 2016 to June 2020 were analyzed retrospectively. The overall survival (OS) rate, cumulative progression-free survival (PFS) rate, relapse rate, non-relapse mortality (NRM), regimen related toxicity (RRT) and risk factors affecting prognosis of the patients were analyzed. RESULTS: The 1-year OS and PFS of the patients after implantation was (78.8±8.6)% and (79.8±8.1)%, while the 1-year cumulative relapse rate and NRM of the patients was 9.3% and 22.0%, respectively. The 1-year expected OS of MRD- high-risk patients before HSCT was 100%. The 1-year expected OS and PFS of the patients in pre-transplant relapse group was (46.9±18.7)% and (50.0±17.7)%, respectively. The incidence of I/II grade RRT was 39.3%. NO III/IV grade RRT were found in 28 patients. Multivariate analysis showed that pre-transplant relapse was the independent risk factor affecting OS and PFS of the patients. CONCLUSION: The intensified conditioning regimen of cladribine in combination with BuCy can reduce the relapse rate of high-risk AML transplantation, and its RRT is mild, exhibiting good safety. MRD- high-risk patients before HSCT can achieve better transplant benefits, but the prognosis of patients with relapse before transplantation is not significantly improved. Therefore, for non-relapsed high-risk AML patients, this intensified conditioning regimen deserves to be considered.