Comparison Of Cell Morphology And Flow Cytometry In The Diagnosis Of Multiple Myeloma

Background:Multiple myeloma(MM)is a malignant plasma cell-related disease,and It is the most common type of plasma cell proliferative disease,mainly seen in the elderly,its main characteristics are monoclonal plasma cells in the bone marrow of malignant hyperplasia,accompanied by extensive infiltration,including bone,nervous system,liver,spleen,lymph nodes and so on.The clinical manifestations of this disease are varied,including hypercalcemia,renal insufficiency,anemia and osteolysis.Because the clinical manifestations of this disease are complex and diverse,without clinical specificity,its first symptoms are often misdiagnosed as relatively common diseases in clinical work.Laboratory examination of the disease is the key diagnostic basis,including blood,bone marrow,flow cytometry(FCM)detection of the immune phenotype,hematuria immunofixation electrophoresis,blood biochemistry and other tests.In recent years,with the aggravation of the aging of China's population,the deepening of clinical understanding of the disease and the continuous development of various laboratory examination methods,the detection rate of the disease increased significantly,but the rate of misdiagnosis and missed diagnosis is still high.Bone marrow cytology is an important basis for the diagnosis of this disease.However,due to the focal distribution of myeloma cells,the proportion of plasma cells detected by bone marrow cytology often fails to meet the diagnostic criteria.At the same time,some well-differentiated myeloma cells are difficult to distinguish from normal plasma cells,which brings great difficulties to clinical work.In recent years,the rapid development of follow up flow cytometry has provided an important basis for improving the detection of multiple myeloma,which is characterized by rapid,objective and sensitive.At the same time,it can detect minimal residual lesions(MRD),providing a basis for guiding the prognosis.Flow cytometry tend to have high sensitivity,in clinical work,we found some leukemia,such as acute lymphoblastic leukemia(ALL),acute myelogenous leukemia(AML)and flow cytometry to detect the proportion of leukemia cells possess nuclear often greater than bone marrow cytology,but in the opposite was true for the detection of multiple myeloma.Therefore,two detection methods,cell morphology and flow cytometry,were explored to analyze the correlation and comparison between them,so as to strengthen the understanding of the diagnosis of multiple myeloma and improve the detection of multiple myeloma.Objective:To explore the value of cell morphology and flow cytometry in the diagnosis of multiple myeloma(MM).Methods : Through the study of bone marrow cytology,bone marrow pathology,immunofixation electrophoresis,flow cytometry,clinical manifestations,imaging,serum biochemistry and other indicators of 166 patients diagnosed,these 166 cases are newly diagnosed(ND)patients.The proportion of abnormal plasma cells in MM patients was detected by cell morphology,and the proportion of abnormal plasma cells in MM patients was detected by tri-color fluorescence flow cytometry,and the immunophenotype of myeloma cells was detected.The correlation and difference of the proportion of myeloma cells detected by the two methods were analyzed,and the common immunophenotypic characteristics of myeloma cells were analyzed.Results:166 MM patients were divided into 3 groups according to the proportion of plasma cells detected by cytology: 93 cases with the proportion of plasma cells greater than 30%(group A),43 cases with the proportion of plasma cells less than 30% and greater than 10%(group B),and 30 cases with the proportion of plasma cells less than10%(group C).In 16 patients,cytological detection of plasma cell ratio was correlated with flow cytometry detection of plasma cell ratio(R= 0.748,P<0.001).There was A correlation between the proportion of plasma cells detected by two detection methods in groups A,B and C(the R values were 0.496,0.477 and 0.566,respectively,and all P values were <0.05).In 166 patients,the proportion of myeloma cells in bone marrow cytology was higher than that in flow cytometry,and the difference was statistically significant(P<0.001).The proportion of plasma cells detected by bone marrow flow cytometry was higher in group A and group B than in group B(P<0.001).The results of the two detection methods in group C were not statistically significant(P > 0.05).The immunophenotypes of myeloma cells were similar to CDl9-CDl38+CDl38+CD56+/-CD45 dim ~-,in which the positive rate of CD19 was 1.2%,the positive rate of CD56 was 80.7%,the positive rate of CD38 was 100%,the positive rate of CD138 was100.0%,and the expression of CD45 was often negative or weakly positive.The proportion of plasma cells detected by bone marrow cytology in all the 30 patients in group C was less than 10%.According to the analysis of immunophenotype,the immunophenotypic characteristics were similar,all of them were CDl9-CD38 +CDl38+CD56+/-CD45 dim ~-.The 30 patients were later diagnosed as multiple myeloma according to bone marrow pathology,hematuria immunofixation electrophoresis,and relevant clinical symptoms.Conclusions:There is a certain correlation between the two detection methods.The quantitative detection of myeloma cells by cell morphology is better,and the qualitative detection by flow cytometry is better.Combining the two detection methods can significantly improve the detection rate of multiple myeloma.