The Effect Of WT1 Expression On The Prognosis Of Allogeneic Hematopoietic Stem Cell Transplantation In Acute Leukemia

ObjectiveTo study the effect of WT1 expression level on the prognosis of allogeneic hematopoietic stem cell transplantation(allo-HSCT)in patients with acute leukemia(AL)and its significance as a molecular marker for dynamic monitoring of minimal residual disease(MRD).MethodRetrospectively analyzed those AL patients who underwent allo-HSCT in our center during Jan 2016-Dec 2017,a total number of 314 cases,93 cases were diagnosed with WT1 positive and 221 cases were negative.The difference in expression levels of each type of leukemia in the WT1-positive group was compared.Overall survival(OS),disease free survival(DFS),and cumulative incidence of relapse(CIR)were compared between WT1 positive and negative groups.Comparing the difference of WT1 expression at diagnosed,pre-HSCT and after HSCT.Using the receiver operating characteristic curve(ROC curve)to determine the threshold of WT1 expression before transplantation,within 3 months after transplantation and 6 months after transplantation.The threshold of WT1 expression before transplantation was 1.010%,within 3 months after HSCT was 0.079%and 6 months after HSCT was 0.375%.According to these thresholds,WT1 positive patients were divided into low expression groups and high expression groups.Analyzed the relationship between OS,DFS,CIR and WT1 expression.ResultThere was a difference in the expression level of each type of leukemia in the WT1 positive group.The expression of ALL was significantly lower than that of AML(P=0.020).The expression of M5 was relatively low in AML patients,and the expression of Ml was higher.However,the difference was not statistically significant(P=0.103).Compared with the changes of WT1 expression at the time of initial diagnosis,before transplantation and after transplantation.WT1 expression before transplantation was significantly lower than that of initial diagnosis(Z=6.919,P<0.001).The expression of WT1 within 3 month after transplantation was lower than that before transplantation(Z=2.324,P=0.020).Chemotherapy and transplantation could reduce the expression level of WT1,but neither could make WT1 expression continue to be negative.There was no significant difference in OS,DFS and CIR between the WT1 positive group and the negative group at the time of initial diagnosis(P=0.3 80;P=0.660;P=0.730).The OS and DFS of high expression group pre-HSCT were lower than low expression group(P=0.000;P=0.000).The CIR of high expression group was higher than that of low expression group(P=3.589*10-5<0.05).There was no significant difference in OS,DFS and CIR between WT1 high expression group and low expression group 3 months after transplantation(P=0.157;P=0.316;P=0.316).The OS and DFS of WT1 high expression group at 6 months after transplantation were lower than those of low expression group(P=0.002;P=0.022).But there was no significant difference in CIR between these two groups(P=0.133).ConclusionIt is not meaningful to dynamically monitor the condition and judge the prognosis by simply using WT1 positive or negative.High expression of WT1 before and after HSCT was an adverse prognosis factor.It is of clinical practical value to use WT1 as a transplant recommendation index for patients with acute leukemia and as a marker to monitor MRD dynamically.