The Immunophenotype Characteristics And Prognostic Correlation Analysis Of Each Subtype Of AML

Background and ObjectiveAcute leukemia is a highly heterogeneous hematological malignancy characterized with abnormally immature cells originated from the hematopoietic stem cells and hematopoietic progenitor cells.Leukemia cells can't be fully developed and they would stay in a certain stage of archaeocyte and blast development.Thus,leukemia cells have unique immunophenotypic features.Antigens in the cytoplasm and cell membrane were marked with monoclonal antibodies by flow cytometry?FCM?to analyze the origin and differentiation of leukemia cells and detect asynchronous expression,cross-lineage expression,down-regulated and up-regulated expression of lineage related antibodies.This technology not only complements morphological diagnosis,but also figures out more biological behaviors of leukemia cells.Moreover,it can enhance diagnosis accuracy and provide evidence for biological target therapy.This study aimed to provide an overview of antigens in AML,including the expression characteristics,diagnostic value,difference in subtypes expression and their correlation with therapeutic efficiency.MethodWe consecutively collected clinical data of 113 de novo AML patients in The First Affiliated Hospital of Dalian Medical University from December 2014 to December 2016.The data obtained included bone marrow morphology,immune phenotype assayed by FCM,chromosome karyotype and the results of molecular biological assays.These collected data were analyzed by chi-square test,and statistical significance was set at the level of P=0.05.Results1.The result showed that 62 out of 113 cases of AML patients were identified as AML-M2 with the median age of 56.5.22 cases were AML-M5 with the median age of 56 and 12 cases were AML-M3 with the youngest median age of 41.5.The positive rates of myeloid antigens in AML patients were shown as follows: CD117 88.5%>CD33 85.0%>CD13 84.1%>CD34 73.5%>HLA-DR 68.1%,whereas the expression of CD64,MPO,CD38,CD123,CD36,CD14 and CD15 was low.2.The expression intensity of CD117,CD13 and CD33 in M2,M3 and M5 patients was high.AML-M3 patients were found to be CD13 and CD33 positive,and they had the decreased frequency of CD34 expression and a lack of HLA-DR expression.The positive rate of CD13?90%?in M2 a was significantly higher than that in M2b?P<0.05?.CD14,a monocyte associated antigen,had high specificity but low sensitivity in identifying AML-M4 and AML-M5.The positive rate of CD34,HLA-DR,CD38,CD123 and CD56 was significantly higher in M5 than in other subtypes?except M3??P<0.05?.3.31.8% of AML patients were accompanied with the lymphoid antigens expression,among which,CD56 and CD7 were the most common ones.And the lymphoid antigen expression in M2 and M5 was obviously higher than in other subtypes.Partial M5 patients expressed specific lymphoid antigens.So as to CD20,3 cases of CD20 expression were all in M3.The expression of CD19 in AML could only be observed in AML-M2 and AML-M5,especially in M2 b.4.The remission rate of CD56 positive group was 66.7%?4/6?,whereas the remission rate of CD56 negative group was 100%?11/11?.Thus,the remission rate of CD56+ AML patients?except M3?was lower than that of CD56-AML patients.5.Three cases of M₀ were misdiagnosed as ALL and one case of acute biphenotypic leukemia was misdiagnosed as AML by morphologic assessment.They were all corrected by immunophenotyping.Conclusions:1.CD117,CD33 and CD13,the highly expressed antigens in AML,are of great value in determining the origination of AML.2.Immunophenotyping studies are helpful in the classification of AML,especially for the diagnosis of AML-M3.3.AML patients can have the cross-lineage expression of lymphoid antigens,the expression of CD2 and CD19 suggests the possibility of M3 and M2 b respectively.4.CD56+ can be used as AML independent prognostic factor.5.The identification of some special subtypes,such as AML-M₀ and biphenotype,is dependent on immunophenotyping since morphological examination could lead to the misdiagnosis as ALL.