Associations between M-protein and bone marrow fibrosis in newly diagnosed multiple myeloma

Abstract

Objectives: Myelofibrosis may occur as a primary condition or secondary to several malignant or non-malignant conditions. Multiple myeloma (MM) is a malignant condition in which collagen fibrosis and reticulin fibrosis may coexist. This study aimed to investigate the prevalence of bone marrow fibrosis in newly diagnosed MM and potential associations between serum M-protein concentrations and bone marrow fibrosis. Material and Methods: Ninety patients with newly diagnosed MM were retrospectively assessed in this study. Demographic characteristics, blood counts, blood biochemistry, bone marrow plasma cell percentage, and bone marrow fibrosis grades were recorded. Results: The bone marrow plasma cell percentage was ≥50% in 34.4% of patients and <50% in 65.6% of patients. The bone marrow plasma cell percentage was found to be 55% in the high fibrosis group and 42% in the low fibrosis group (P = 0.04). Bone marrow fibrosis was detected at a high level in 23.3% of the patients. No statically significant differences were found between the high fibrosis group and the low fibrosis group in the parameters, including age, sex, the type of myeloma, hemoglobin concentrations and platelet counts at diagnosis, β2 microglobulin, lactate dehydrogenase, disease stage, and erythrocyte sedimentation rate that were assessed in the study (P > 0.05). A statically significant association was found between lower fibrosis levels and higher Ig M and serum kappa levels and serum kappa/lambda ratio (P = 0.02, P = 0.03, and P = 0.03, respectively). Conclusion: In this study, significant correlations were found between low-grade bone marrow fibrosis to high IgM and the kappa/lambda ratio. In conclusion, in this study, it was shown that bone marrow fibrosis in MM differs according to subtypes.