The clinicopathologic features and prognostic impact of MYD88 L265P (MYD^L265P) and CXCR4 mutations (CXCR4^Mut) have been well reported, although little is known regarding the impact of chromosomal aberrations (CA) detected by chromosome banding analysis (CBA) in symptomatic Waldenström’s macroglobulinemia (sWM). Thus, we investigated the clinicopathologic features and prognostic impact in sWM with CAs identified by CBA. We retrospectively analyzed the clinicopathologic results and genomic alterations by droplet digital PCR, fluorescence in situ hybridization (FISH), and CBA using the G-banding method in bone marrow samples from sWM patients collected between April 2010 and March 2024 at our institute. The relationship between CAs and clinicopathologic features was evaluated, as well as the time to next treatment (TTNT). Thirty-five patients were enrolled. The median age was 71 years, and the median hemoglobin level was 10.1 g/dL. The median serum IgM and M-protein levels were 3,009 mg/dL and 2.95 g/dL, respectively. MYD^L265P was found in 30/35 patients (85.7%), whereas CXCR4^Mut was found in 3/35 patients (8.6%). Deletion 6q identified by FISH in 5/18 patients (28%), and CAs using CBA in 9/34 patients (26%), including 4/34 (12%) complex karyotypes. sWM with CAs had more anemia (p = 0.04) and hypoalbuminemia (p = 0.007), in addition to higher serum M-protein and IgM levels (p = 0.03). With a median follow-up of 73 months, the median TTNT in patients with and without CAs was 27 and 68 months, respectively. CAs with CBA may be associated with clinical aggressiveness and shorter TTNT in sWM.

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.

Non-Waldenström macroglobulinemia (non-WM) lymphoplasmacytic lymphoma (LPL) is a rare subtype with limited clinical evidence and no confirmed treatment guidelines. Bruton tyrosine kinase (BTK) inhibitors represent one of the mainstay therapies in WM, but their role in non-WM LPL remains unclear. We report a case of IgG-type non-WM LPL successfully treated with a second-generation BTK inhibitor, tirabrutinib. The patient demonstrated a rapid decline in M-protein and improvement in anemia, with a durable partial response. This case adds to the limited literature supporting BTK inhibitor use in non-WM LPL and highlights the need for further studies to define optimal treatment strategies.

Other iatrogenic immunodeficiency lymphoproliferative disorders (oii-LPD) are defined as lymphoid proliferations or lymphomas that occur in patients taking immunosuppressive agents (ISA) for autoimmune disorders (AID). Although methotrexate and tumor necrosis factor-alpha inhibitors cause oii-LPD, the association between corticosteroids and lymphomagenesis remains unknown. Herein, we present the case of a 51-year-old woman with oii-LPD caused by corticosteroid use for autoimmune hemolytic anemia (AIHA). The diagnosis of AIHA was made in May 2016, and AIHA had been well-controlled for 5 years with oral prednisolone (PSL). During a regular follow-up visit in March 2022, an abnormal increase in atypical lymphoid cells in the peripheral blood was found. The bone marrow biopsy specimens showed local aggregations of large cells that were identified as lymphoplasmacytic cells and plasma cells, and that were positive for cluster of differentiation (CD)19 and CD20, with apparent nucleoli among the diffuse infiltration of atypical small lymphocytes. The large cells were partially positive for the Epstein–Barr encoding region in situ hybridization and latent membrane protein 1, which confirmed Epstein–Barr virus (EBV)-affected lymphomagenesis. To our knowledge, this is the first report of an oii-LPD case shown to be induced by corticosteroid use for AID.

Extramedullary hematopoietic effusion (EHE) is one of the extremely rare phenomena associated with extramedullary hematopoiesis, which is caused by serous effusions, including pleural effusion, and may be related to hematologic disorders and neoplasms. Herein, we present the case of an 81-year-old man with EHE accompanying Waldenstr & ouml;m's macroglobulinemia (WM). The patient complained of anemia and dyspnea. The chest X-ray and computed tomography showed a massive left pleural effusion, and the aspirates revealed infiltration of the immature myeloid cells and megakaryocytes, in addition to the lymphoma cells. To our knowledge, this is the first report of EHE in WM.