Prognostic Significance of Paraproteinemia in Marginal Zone Lymphoma.

[OBJECTIVE] The prognostic significance of paraproteinemia (PP) in marginal zone lymphoma (MZL) is underexplored. We aimed to investigate the clinical and biological impact of PP and its association with survival outcomes in patients with MZL.

[MATERIALS AND METHODS] We retrospectively evaluated 73 patients diagnosed with MZL between 2000 and 2022 at a single center. Baseline clinical characteristics and survival outcomes were compared according to PP status.

[RESULTS] PP was present in 27.3% (20/73) of patients, predominantly of the immunoglobulin M (IgM) subtype. PP was significantly associated with older age (p<0.001), advanced disease stage (p=0.023), elevated β2-microglobulin (p=0.001), bone marrow involvement (p=0.026), and lower hemoglobin (p=0.002) and albumin (p<0.001) levels. Patients with PP had significantly shorter overall survival (OS) and progression-free survival (PFS) compared to those without PP (mean OS: 73.8 vs. 178.8 months, p=0.046; mean PFS: 63.5 vs. 159.7 months, p=0.049). The negative prognostic impact was more pronounced among patients with IgM PP (OS: 58.8 vs. 178.2 months, p=0.006; PFS: 45.2 vs. 157.4 months, p=0.004). In histological subtype analysis, only mucosa-associated lymphoid tissue lymphoma patients with IgM PP showed significantly shorter OS (70.5 vs. 152.6 months, p=0.010). Patients with IgM PP treated with R-CHOP-like regimens experienced significantly shorter PFS and OS.

[CONCLUSION] PP, particularly of the IgM subtype, is associated with adverse clinical and biological features and predicts inferior survival in patients with MZL. Evaluating PP status at diagnosis as a potential prognostic marker may guide treatment strategies. Prospective studies are needed to confirm the prognostic utility of PP and support its incorporation into MZL treatment management.