Efficacy and safety of therapeutic procedure for Waldenström's macroglobulinemia with hyperviscosity syndrome.

Introduction: Hyperviscosity syndrome (HVS) is a significant complication in Waldenström's macroglobulinemia (WM), although the significance of plasmapheresis in clinical practice has not been clarified. To confirm the efficacy and safety of plasmapheresis followed by primary therapy for WM with HVS, we retrospectively conducted this study. Methods: Untreated WM with HVS, or serum immunoglobulin M (IgM) levels ≥4000 mg/dL, were analyzed. The basic therapeutic flow was conducted as follows: (1) performing plasmapheresis, (2) followed by primary therapy without rituximab, and (3) performing the second cycle. The serum IgM reduction rate and adverse events (AEs) were evaluated. Results: Ten patients were enrolled. The median serum IgM levels at diagnosis, post‐plasmapheresis, after the first cycle of primary therapy, and after the second cycle were 5174, 2900, 3286, and 2657 mg/dL, respectively. No patients experienced IgM flare or bleeding AEs. Conclusion: The therapeutic flow offers sufficient efficacy and safety in WM with HVS. [ABSTRACT FROM AUTHOR]