Application of Capillary Electrophoresis in Monoclonal Gammopathies and the Cutoff Value of Monoclonal Protein in Differential Diagnosis of Multiple Myeloma and Other Monoclonal Gammopathies

OBJECTIVEMonoclonal protein (MP) exists in various diseases, and capillary electrophoresis (CE) has been widely used to detect MP. However, there is not much research on the application value of MP in the differential diagnosis of monoclonal gammopathies. This study aimed to explore MP's cutoff value for the differential diagnosis of multiple myeloma (MM) and other monoclonal gammopathies (MGs). METHODSA retrospective analysis of 8167 cases was conducted. Serum MP was detected by CE, and the patients' clinical information was collected from the clinical database of our hospital. RESULTS985 cases had MP with high peaks, and 91.1% were diagnosed with malignant diseases. The MP showed small peaks in 471 cases, and only 24.4% were diagnosed with malignant diseases. Among the MPs, the IgG-κ type was the most common type, followed by the IgG-λ, IgA-κ, IgA-λ, free λ light chain, IgM-κ, free κ light chain, double clone, and IgM-λ types. Differences in the MP of the IgG, IgA, IgM, and FLC types between the MM group and MGUS group were statistically different (P13.86g/L, and >10.15g/L, respectively, for the differential diagnosis of MM and other MGs. The cutoff value of the MP of IgM for the WM diagnosis was >37.75 g/L. CONCLUSIONCE has good clinical application value in the diagnosis of monoclonal gammopathies, and MP can be used in the differential diagnosis of MM and other monoclonal gammopathies.