Clinical Significance Of FLT3-ITD In Newly Treated Of Adult With Acute Monocytic Leukemia

FMS-like tyrosine kinase 3(FLT3)is a member of the type III tyrosine kinase receptor family,and its mutations can regulate the proliferation and differentiation of bone marrow hematopoietic cells by binding to ligand(FL).FLT3 gene mutations mainly include ITD and TKD.The results show that the abnormal mutation of FLT3-ITD is a common type in acute myeloid leukemia(AML).It can activate the tyrosine kinase receptor and promote the spontaneous proliferation of cells,thereby affecting the occurrence of acute myeloid leukemia(AML),Development and prognosis.Based on the analysis of genetic characteristics and testing,FLT3-ITD-positive is generally considered to have a worse prognosis than negative,and most studies have found that patients with FLT3-positive AML often have clinically high white blood cell counts in peripheral blood,an increase in the proportion of bone marrow progenitor cells,and easy treatment after Recurrence,short survival,and other characteristics have proven that the occurrence,development,and poor prognosis of AML are closely related to FLT3 mutations.Therefore,it is considered by most clinicians as one of the independent factors of poor prognosis of AML patients.Objective:This study compared the clinical characteristics of FLT3-ITD positive and FLT3-ITD negative newly diagnosed adult M5 patients,and studied the effect of FLT3-ITD mutations on the efficacy and prognosis of M5 patients,providing a reference for clinical treatment.Methods:A retrospective analysis method was used to collect AML patients diagnosed from May 2015 to October 2018 in the Hematology Department of the First Central Hospital of Baoding City,and select 62 M5 patients who met the research criteria.According to FLT3-ITD mutations,they were divided into FLT3-ITD positive group and FLT3-ITD negative group.The clinical characteristics,efficacy and prognosis of the two groups were compared.Results:1.Comparison of general clinical data between FLT3-ITD positive group and FLT3-ITD negative group: the male to female ratio of 62 M5 patients is 1.3:1,and the median age is 56(19-87)years old.There was no significant difference between 34 FLT3-ITD positive patients and 28 negative patients in gender,basic disease,physical condition,age of onset and other basic characteristics(P > 0.05);while in FLT3-ITD positive group,there were significant differences in hyperleukocytemia,absolute monocyte count of peripheral blood,high tumor load,proportion of bone marrow primordial cells,extramedullary infiltration and other aspects compared with the negative group Significance(P < 0.05).2.Comparison of curative effect and prognosis of patients in the FLT3-ITD positive group and the negative group: 10 cases of FLT3-ITD positive group achieved complete remission(CR)after induction of remission,accounting for 29.41%,compared with the negative group(50%),the difference There was no statistical significance(P> 0.05);the relapse rate in the FLT3-ITD positive group was 80%,the median survival time was 17.9 months(95% CI,14.5-21.2),and the average remission time was 4.4 months(95%(CI,2.8-6.0),the relapse rate in the negative group was 42.85%,the median survival time was 41.4 months(95% CI,33.4-49.5),and the average remission time was 37.2 months(95% CI,32.3-42.1),and Compared with the negative group,the differences were statistically significant(P <0.05).Of the 34 FLT3-ITD positive patients,3 received FLT3-positive patients during the consolidation phase and 1 received FLT3 with MLL.The PR was evaluated before transplantation,and recurrence occurred more than 20 days after transplantation.The total survival was 4 months.The other two FLT3 positive patients survived 8 months and 11 months,respectively.4.Correlation between FLT3-ITD positive group and NPM1 mutation: In the combined NPM1 mutation rate,FLT3-ITD positive(26.47%)was significantly higher than the negative group(7.14%),and the difference was statistically significant(P <0.05).The median OS of FLT3-ITD-positive patients with NPM1 was higher than that of the single-yang group(24 months vs 13.6 months).The difference between the two groups was statistically significant(P <0.05).5.Multivariate analysis by COX proportional hazards model showed that FLT3 gene mutation and AMC were risk factors affecting overall survival of M5(P <0.05).Conclusion:Patients with FLT3-ITD positive M5 were prone to hyperleukocytemia,high proportion of bone marrow primordial cells,high peripheral blood absolute monocyte count,high tumor load and high extramedullary invasion.The early remission rate of FLT3-ITD positive patients was similar to that of negative patients,DFS was shorter and survival was worse.The early remission rate of NPM1 positive patients was better than that of single positive patients.The remission rate of HAD was higher than that of DA,and there was no difference in survival.