Clinical significance of WT1 in the evaluation of therapeutic effect and prognosis of non-M3 acute myeloid leukemia.

Abstract

To explore the clinical significance and prognosis of acute myeloid leukemia (AML) patients with WT1 mutations.In total, the clinical data of 269 adult patients with non-M3 AML were considered retrospectively. From these patients, 153 carried WT1 mutation whereas 116 were negative. WT1 mutation positive patients were further divided into WT1 low expression and high expression groups base on the expression level of WT1 by qPCR at diagnosis (cut off: 170500). Survival and therapeutic effect analysis were performed for the above patients with different interfering factors such as co-mutations, the extent of WT1 log reduction and the chemotherapy regimens. Patients with high WT1 expression have higher rate of relapse. We can accurately identify patients with inferior outcomes when we take the following factors into consideration: the WT1 expression level at diagnosis; different prognostic factors including co-mutations (especially NPM1 and FLT3-ITD); the log reduction of WT1 after induction therapy and the risk of stratification. Idarubicin + Cytarabine (IA) regimen could reduce the expression level of WT1 after treatment, and Allo-HSCT played an important role in improving the prognosis of patients with WT1 high expression and patients with WT1 negativity. Among the relapsed patients, there existed a rising trend of WT1-MRD in advance than MFC-MRD and that of patients with continuous complete remission (CR). Different clinical background should be taken into consideration when we judge the prognosis and therapeutic effect of patients with WT1 mutations. In addition, WT1 may be an optional MRD marker, which needs regular monitoring.