Clinical Significance Of Early Lymphocyte Recovery After Allogeneic Hematopoietic Stem Cell Transplantation In Acute Myeloid Leukemia

BackgroundAllogeneic hematopoietic stem cell transplantation(allo-hsct)is an important or even the only method to cure acute myeloid leukemia(AML)at present.Relapses after transplantation after early prediction and targeted intervention measures can significantly reduce the relapse rate(RR),improve Overall survival rate(OS),and significantly improve the prognosis of transplantation.However,there is still a lack of high sensitivity and specific biological indicators that can accurately predict the recurrence of disease after transplantation.Early lymphocyte count indicates the recovery rate of lymphocytes,which is an important indicator of immune reconstruction after transplantation,and may indicate the strength of graft-versus-leukemia(GVL).However,whether it has predictive effect on recurrence after transplantation is still controversial.Objective1.To monitor peripheral blood lymphocyte count after allogeneic hematopoietic stem cell transplantation in patients with acute myeloid leukemia,and to explore its clinical significance in predicting early recurrence and prognosis.2.To investigate the clinical significance of lymphocyte subsets recovered early after transplantation in predicting early recurrence and prognosis.Methods1.A retrospective analysis was performed on 103 patients with acute myeloid leukemia who were treated with allo-HSCT in the hematopoietic stem cell transplantation center of the hematology department of our hospital from January2011 to September 2018.The Absolute lymphocyte count(ALC21)of peripheral blood at+21 days after transplantation was used to represent the recovery rate of lymphocytes.ALC21?0.5×10~9/L was used to represent the high ALC21 group,and ALC21<0.5×10~9/L was used to represent the low ALC21 group.Relapse rate,OS,disease-free survival rate(DFS)and other indicators were calculated.2.Multi-parameter flow cytology was used to detect the lymphocyte subsets+21days after transplantation of allo-hsct in AML patients treated in our hospital from September 2018 to February 2019.Results1.Among the 103 patients with AML after transplantation,30 had recurrence,with a recurrence rate of 29.1%.The recurrence rates of the ALC21 high group and the ALC21 low group were 20.0%and 41.9%respectively,with statistically significant differences(P=0.016).2.Of the 103 patients with AML after transplantation,38 died,of whom 21 died of recurrence,with a relapse-related mortality of 20.4%.65 cases survived.2-year OS and 2-year DFS of the ALC21 high group and the ALC21 low group were 74.6%and50.0%,respectively(P=0.010),and 71.2%and 47.7%,respectively(P=0.016),with statistically significant differences.The total infection rate of EBV and CMV in all patients after transplantation was 45.6%,and that in the ALC21 high group and ALC21 low group was 30.5%and 60.5%,respectively(P=0.011),the difference was statistically significant.3.A total of 12 patients with lymphocyte subsets were detected.Among the67patients with high ALC21,the proportion of NK cells was significantly increased in 5 cases,and CD3+T cells dominated in the other 2 case.ConclusionsEarly lymphocyte recovery after allogeneic hematopoietic stem cell transplantation in patients with acute myeloid leukemia can early predict disease recurrence and prognosis after transplantation,and NK cells may play a major role in early lymphocyte recovery and immune reconstruction.