Clinical Observation On 49 Cases Of Minimal Residual Disease In Patients With Multiple Myeloma Detected By Multiparameter Flow Cytometry

Objective:Based on the analysis of 49 patients with multiple myeloma(MM)in our department’s newly diagnosed immunophenotyping,minimal residual(MRD)and other relevant clinical data,the significance of detecting minimal residual by multiparameter flow cytometry(MFC)in patients with multiple myeloma and the feasibility of detecting minimal residual in MM patients by MRD detection scheme designed by our department on 6-color flow cytometer are discussed.Methods:The newly diagnosed immune typing,MRD and other relevant laboratory indexes of 49 MM patients admitted to the Department of Hematology,First Affiliated Hospital of Kunming Medical University from 2017 to March 2019 were collected.Flow analysis results were compared with the results reported in relevant literatures.SPSS23.0 was used to analyze the clinical characteristics of MRD negative group and positive group and the influencing factors of MM progression-free survival.GraphPad Prism 5 analyzed the differences of PFS between MRD negative and positive groups and MRD positive groups at different levels.Results:1.The detection rate of antibodies related to flow cytometry in 49 MM patients at first diagnosis is basically the same as that reported in most literatures(except CD45);2.Compared with the clinical features in MRD negative group and MRD positive group,β2 microglobulin(χ2=4.744,P=0.026)and bortezomib chemotherapy(x2=4.013,P=0.045)have statistical significance for MRD negative conversion;3.PFS of MM patients in MRD negative group and positive group was different for 2 years(P=0.012);4.In multivariate Cox analysis,MRD positive(P=0.044,HR=2.116,95%CI 0.014-1.943)is an independent risk factor for PFS in MM patients.Among the 5,49 patients,22 achieved complete remission(CR)after chemotherapy,of which 10 achieved CR with negative MRD detection and 12 achieved CR with MRD detection results ranging from 0.04%to 0.3%.Conclusions:1.Monitoring MRD can be used to evaluate the therapeutic effect,observe the degree of disease control,and judge the prognosis of patients.Reaching MRD negative status and its duration should be regarded as the ultimate goal of MM therapy.2.Using MFC to detect MRD can reflect the degree of disease remission more deeply and sensitively than traditional evaluation methods,and is closely related to disease prognosis.3.The three-tube and six-color scheme designed by us can provide reliable diagnostic basis for newly diagnosed multiple myeloma patients,and can also effectively monitor MRD,providing a simple and quick scheme for flow detection of MM.