Evaluation of M-Protein Patterns and Different Correlations in Patients with Multiple Myeloma

Abstract

Kumar Sarkar, A N M Ehsanul Karim, Md. Shafiul Azam, A.H.M. Sanjedul Haque Sumon, Md. Ahsanul Kabir, Sujon Sarker, Samim Reza and Sraboni Biswas

Introduction: M-protein plays an important role in diagnosis, prognosis and treatment monitoring in Multiple Myeloma.

Aim of the study: This study aimed to evaluate M-protein patterns and their different correlation in patients with Multiple Myeloma.

Methods: This descriptive cross-sectional study was conducted in the Department of Hematology at Shaheed Ziaur Rahman Medical College Hospital and private consultation center in Bogura from 2019 to 2024. A total of 77 confirmed multiple myeloma patients were included. M-protein was analyzed using serum protein electrophoresis, immunofixation and immunoturbidimetry alongside routine biochemical parameters. Data were statistically analyzed using SPSS version 25.0. Ethical approval was obtained from the institutional review board. Results: A total of 77 patients with multiple myeloma were analyzed. Most participants were aged >50 years (83.1%), with a male predominance (64.9%). The gamma region was the most frequent M-protein electrophoretic zone (72.7%), followed by the beta-2 region (26.0%). IgG was the predominant heavy chain (57.1%), while kappa light chains were more common than lambda (64.9% vs. 35.1%). Combined heavy- and light-chain expression was observed in 87.0% of cases, and the most frequent subtype was IgG–kappa (36.4%). The mean M-protein concentration was 3.38 ± 2.28 g/dL; 45.5% had levels >3 g/dL, and 33.8% showed an involved/uninvolved light chain ratio >100, with both criteria present in 13.0%. Elevated M-protein (>3 g/dL) was significantly associated with heavy chain type (p = 0.036) but not with light chain type (p = 0.896). Quantitative M-protein correlated strongly with total serum protein (r = 0.937, p < 0.001) and inversely with serum albumin (r = –0.344, p = 0.002) and albumin–globulin ratio (r = –0.792, p < 0.001). A significant association was observed between heavy chain type and electrophoretic zone (p < 0.001), with IgG predominating in the gamma region and IgA in the beta-2 region.

Conclusion: This study shows that M-protein patterns in Bangladeshi multiple myeloma patients commonly exhibit IgG– kappa predominance and gamma-region migration. Quantitative M-protein levels correlate strongly with total serum protein and inversely with serum albumin and albumin–globulin ratio, reflecting the disease's biology. Only a small number of patients met both M-protein >3 g/dL and light chain ratio >100, indicating significant biological variability. The relationship between heavy chain subtype and migration zone, along with IgG subtype and higher M-protein concentration, highlights the importance of combined electrophoretic and immunoglobulin profiling in diagnostics.

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