Clinical Study Of DC-CIK Cells In The Treatment Of Recurrent Acute Myeloid Leukemia After Allogeneic Hematopoietic Stem Cell Transplantation

Objective:This study was designed to evaluate the safety and clinical efficacy of DC-CIK cells in the treatment of relapsed acute myeloid leukemia(AML)after allogeneic hematopoietic stem cell transplantation(allo-HSCT).To explore the clinical value of DC-CIK cells in the treatment of relapsed leukemia,and to explore the mechanism of action,and to explore new ideas for the treatment of relapsed leukemia.Methods:To observe the relapsed acute myeloid leukemia patients after transplantation who were treated with DC-CIK cells from July 2009 to July 2014 in our hospital.The main observation indexes were CR,GVHD,OS,PFS and adverse events.CR refers to recovery of hematopoietic function,neutrophil absolute count>1.5×10~9/L,platelet count>100×10~9/L,normal bone marrow blast cells(<5%),WT1 negative or less than 0.02%.GVHD is defined according to published standards.OS refers to the time from the start of cell therapy to death or the last day of follow-up(July 1,2017).PFS refers to the time from post-cell therapy to relapse again or death or the last day of follow-up(July 1,2017).Statistical analysis was performed using statistical software SPSS 23.0.The quantitative data of the skewed distribution were expressed as the median(interquartile range)[M(P25,P75)].The MANN-WHITNEY U method for independent sample non-parametric tests was used to compare the two groups,qualitative data was expressed in percent(%),Fisher's exact test was used for comparison between the two groups,and survival curves were plotted using the KAPLAN-MEIER method.P<0.05 was considered statistically significant.Results:23 patients with relapsed AML after allo-HSCT were treated with DC-CIK.The CR rate was 60.9%,the 5-year survival rate was 43.5%,the 5-year progression-free survival rate was 39.1%,and the incidence of acute GVHD was34.8%,the incidence of chronic GVHD was 15.0%(3/20,3 patients had less than 3 months survival after cell therapy and could not be evaluated).All patients had no serious adverse reactions such as fever and allergy when they infused cells.No acute GVHD occurred above II degree after cell therapy.Only one patient developed extensive chronic GVHD,and 2 patients developed localized chronic GVHD.In particular,there were two patients who achieved complete remission after infusion of DC-CIK cells,followed by different degrees of intramedullary or extramedullary recurrence,and then again given DC-CIK cells for treatment,they are still alive.We further analyzed the efficacy of DC-CIK cells in the treatment of AML patients with molecular biological relapse and hematological relapse.The CR rate of molecular biology relapse was superior to hematological relapse(75.0%and 45.5%),however,we used Fisher's exact test to analyze,there was no significant difference in the remission rate and average survival time between the two groups(P>0.05).Conclusion:This retrospective study suggested:1.DC-CIK cell therapy is safe and effective for patients with relapsed AML after allogeneic hematopoietic stem cell transplantation,especially in patients with early relapse of AML.2.DC-CIK cell therapy has a better remission rate of recurrence of molecular biology than hematological relapse after acute myeloid leukemia transplantation,but there is no statistical difference.3.The incidence of GVHD after treatment with DC-CIK cells was reduced and mild compared with DLI treatment during the same period.Further large-scale randomized studies are needed to evaluate the benefits of DC-CIK cell therapy for relapsed AML after allo-HSCT.