Journal of Clinical and Experimental Hematopathology最新文献

A 79-year-old Japanese woman presented with exertional dyspnea. She had cardiac tamponade and urgent pericardial drainage was performed. Pathological findings from the pericardial fluid revealed non-germinal center B-cell (non-GCB) pericardial large B-cell lymphoma (CD10^-, BCL6⁺, and MUM1⁺). Although a diagnosis of fluid overload-associated large B-cell lymphoma was considered, GCB nodal diffuse large B-cell lymphoma (CD10⁺, BCL6⁺, and MUM1⁺) was discovered through needle biopsy of the enlarged left axillary lymph node. Despite the two lymphomas exhibiting different expression levels of CD10, polymerase chain reaction assessing IgH gene rearrangement suggested a clonal relationship between them. Additionally, MYD88 L265P mutation was confirmed using Sanger sequencing in both samples, suggesting the MCD type. Our case highlights a discrepancy between the Hans' criteria and the gene expression profile-based cell of origin.

Cluster of Differentiation 54 (CD54), also known as intracellular adhesion molecule-1 (ICAM-1), is a transmembrane glycoprotein belonging to the immunoglobulin superfamily. Although CD54 has been shown to be involved in cell-to-cell adhesion and proliferation of B-cell lymphoma cell lines, the clinical significance of its expression has not yet been elucidated. We analyzed Ki-67 indices, the expression status of CD54 and its receptor (CD11a), and the intercellular distance of tumor cells in 40 diffuse large B-cell lymphoma (DLBCL) cases with vascular invasion to analyze the association of cell adhesion and proliferation status. CD54 and CD11a were simultaneously expressed (double-positive) in extra/intravascular tumor cells in 14 (35%) of the cases. Histologically, lymphoma cells of the double positive cases exhibited significantly higher Ki-67 index in extravascular tumor cells than that in the intravascular ones, while no difference was observed in lymphoma cells of the non-double positive cases. The significantly shorter extravascular intercellular distance compared with the intravascular intercellular distance suggested the association between cell-cell adhesion mediated by CD54 and cell proliferation. We further confirmed that the treatment of the recombinant LFA1 (CD11a/CD18) showed the adhesion of human DLBCL-derived cell line HBL-2 to LFA1 and increased cell viability. These findings suggest that cell-to-cell adhesion via CD54 maintains the cell proliferative activity of a subset of DLBCL. This study provides a valuable foundation upon which further research may be conducted to determine detailed mechanisms of cell-to-cell-associated and adhesion-independent cell proliferation.

Reactivation of hepatitis viruses during chemotherapy can be problematic in the treatment of malignant lymphomas. However, studies on reactivation of chronic hepatitis C virus (HCV) infection are limited. A 43-year-old woman presented with generalized lymphadenopathy and multiple liver tumors, and she was diagnosed with follicular lymphoma (grade 3a; clinical stage IV). Chronic HCV infection was clinically diagnosed. Immunochemotherapy (ICT), including bendamustine and obinutuzumab, was initiated with close liver function monitoring without specific treatment for hepatitis C. However, liver dysfunction worsened 17 days after ICT initiation, and ICT was interrupted. HCV-RNA and transaminase levels continued to elevate. Liver biopsy results confirmed acute exacerbation of chronic hepatitis C. Direct active antiviral (DAA) therapy was started and effective. She has maintained a sustained virologic response since DAA therapy ended. With regard to lymphoma, complete metabolic response was maintained for 4 years without additional treatment. Physicians should be aware of HCV reactivation with hepatitis flare after ICT for lymphoma and consider the indication and timing of DAA therapy for hepatitis C in this setting.

Immune checkpoint inhibitors (ICI) are promising therapeutic agents for relapsed or refractory classical Hodgkin's lymphoma (RRcHL). This retrospective study evaluated patients with RRcHL registered in the clinical research program Tohoku-Hematology-Forum-26, between 2016 and 2020, and treated with ICI in 14 centers in Northeast Japan. We analyzed the usage, efficacy, and safety of ICI therapy (ICIT). Among a total of 27 patients with RRcHL, 21 and nine were treated with nivolumab and/or pembrolizumab, respectively. The best response was complete response (CR), partial response (PR), stable disease (SD), and progressive disease in 11 (40.8%), seven (25.9%), eight (29.6%), and one (3.7%) patient, respectively. In all patients undergoing ICIT, the 2-year progression-free survival and 2-year overall survival (OS) were 48.6% and 87.4%, respectively. The 2-year OS for patients with CR, PR, and SD were 100%, 68.6%, and 87.5%, respectively. A total of 36 events of immune-related adverse events (irAEs) or immune-related like adverse events (irlAEs) were observed in 19 of the 27 patients (70.4%). Two thirds of these irAEs or irlAEs were grade 1-2 and controllable. During the observation period, ICIT was discontinued in 22 of 27 (81.4%) patients due to CR, inadequate response, irAE and patient circumstances in five (22.7%), seven (31.8%), eight (36.4%) and two patients (9.1%), respectively. Therapy-related mortality-associated irAE were observed in only one patient during ICIT. These results suggest that ICIT for RRcHL is effective and safe in real-world settings. The optimal timing of induction and duration of ICIT remains to be established.

A 78-year-old Japanese man presented to the emergency department with a sore throat and fever that worsened over 3 weeks. A tonsil biopsy led to the diagnosis of pleomorphic mantle cell lymphoma (MCL) that had infiltrated the right adrenal gland, inferior vena cava, and right atrium (RA). Although the patient's cardiac tumor had high mobility, his hemodynamic state was stable, and he did not present with fatal arrhythmia. Therefore, we first introduced chemotherapy. However, the patient developed recurrent pulmonary embolisms (PEs) and died after starting chemotherapy. An autopsy revealed that the MCL had invaded the large vessels, causing the PEs. Although the high mobility of cardiac tumors is known to increase the risk of PE in diffuse large B-cell lymphoma (DLBCL), optimal management of cardiac MCL remains to be elucidated owing to its rarity. To the best of our knowledge, this is the first report of cardiac MCL with posttreatment PE development in a Japanese patient. It is worth considering preventive surgery before treatment not only in DLBCL, but also in MCL based on the mobility of the cardiac tumors. Our case highlights the need for close communication between hematologists and cardiologists to treat cardiac MCL.

MYD88 p.L265P mutation occurs in over 90% of Waldenström's macroglobulinemia (WM), which is characterized by lymphoplasmacytic lymphoma (LPL) with monoclonal IgM. WM requires careful diagnosis due to overlapping features with other B-cell malignancies. Bing-Neel syndrome (BNS), a rare complication of WM, involves central nervous system (CNS) invasion. This report describes two cases of morphologically low-grade B-cell lymphoma in the bone marrow accompanied by the presence of a large B-cell lymphoma in the brain and a common MYD88 p.L265P mutation, which were eventually established as BNS mimickers. Although the two components in these cases showed the same identical light-chain restriction, different immunoglobulin heavy-chain rearrangement peaks indicated distinct lymphoma stem cells for CNS and bone marrow lesions. These clinical cases emphasize the challenges in diagnosing BNS. Based on the findings, biopsy is recommended for accurate identification of the clonal relationship and MYD88 mutation status.

Alemtuzumab is recommended as first-line and second-line therapies for T-cell prolymphocytic leukemia (T-PLL). This study retrospectively evaluated the efficacy and safety of alemtuzumab in nine Japanese patients with T-PLL at five participating institutions who were treated between January 2015 and August 2023. The median age at first administration of alemtuzumab was 72 years (range, 39 to 78). Two patients were treatment naïve, and seven had been treated with a median of one (range, 1 to 3) prior systemic therapy. Six patients were refractory to their most recent therapy. Three patients completed 12 weeks of treatment. The overall response rate and the complete response (CR) rate were 78% and 11%, respectively. Among the six patients who achieved a partial response, two achieved clinical CR but did not undergo bone marrow examination. One patient also achieved clinical CR but did not undergo CT and bone marrow examination for response evaluation. The median progression-free survival time was 8.1 months (95% confidence interval, 0.9 to 18.6). Three patients received readministration of alemtuzumab monotherapy after disease progression. There were no treatment-related deaths. The grade 3 or 4 nonhematologic adverse events included infusion reaction (grade 3, n = 2), cytomegalovirus reactivation (grade 3, n = 2), and pulmonary edema (grade 3, n = 1). One patient experienced Epstein‒Barr virus-positive diffuse large B-cell lymphoma 15 months after the last dose of alemtuzumab. These results confirm that the efficacy and safety of alemtuzumab monotherapy in Japanese patients are comparable to those previously reported.

In diagnosing TAFRO syndrome, lymph node histology often may not be evaluated due to inapparent lymphadenopathy. In this study, we analyzed the differences in the pathophysiology of TAFRO syndrome with or without lymphadenopathy. We used an anonymous questionnaire to survey 70 hematologists at 50 hospitals in the Kanto Koshinetsu area of Japan from February to April 2020. We received 31 responses and collected 26 cases with TAFRO syndrome. Compared to cases with or without lymph node biopsy, clinical features and laboratory test findings in both groups were not significantly different, except for stronger renal insufficiency found in those without biopsy. It was also revealed that clinical features and laboratory test findings had no significant differences between the cases with and without lymphadenopathy. However, renal insufficiency was more pronounced in those without lymphadenopathy. There were no significant differences in pathophysiology between cases with or without lymphadenopathy in the group that did not undergo lymph node biopsy. In the treatment strategies, no significant differences were found dependent on lymphadenopathy. This study shows that lymphadenopathy in TAFRO syndrome may be secondary to inflammation and unrelated to the underlying disease.

Erdheim-Chester disease (ECD) is a rare, non-Langerhans cell histiocytosis with diverse clinical features. It is characterized by systemic histiocyte infiltration of the bone, skin, central nervous system, lung, kidney, and cardiovascular system. Pericardial involvement is frequently revealed through either pericardial effusion or pericardial thickening in patients with ECD. Although most patients remain asymptomatic, progressive pericarditis, effusion, or cardiac tamponade may occur. Herein, we report a rare and unusual presentation of ECD in a 51-year-old man who experienced severe constrictive pericarditis. The patient presented with uncontrolled fluid retention and heart failure. After the diagnosis of ECD, interferon alpha treatment was administered. The patient recovered dramatically with decreased pleural and pericardial effusion, as well as improvements in the echocardiographic signs of constrictive pericarditis. Despite several therapeutic options described in the literature for managing ECD-related pericardial disease, a standard treatment has not been established. This report highlights the importance of early treatment based on accurate diagnosis of an unusual ECD complication.

The interaction between cancer cells and stromal cells contributes to the pathogenesis of various types of tumors in the tumor microenvironment (TME). Macrophages (Mφs), a type of stromal cell, are transformed into tumor-associated Mφs (TAMs) after integrating within solid tumors. TAMs are known to interact with cancer cells and induce tumor progression. Thus, the cancer cells construct an organ-specific TME, which is advantageous for the survival of cancer cells in the TME. The density of stromal cells is known to be involved in the prognosis of patients with lymphomas. A higher density of stromal cells increases the interaction between lymphoma cells and stromal cells, promoting lymphoma progression. This review focuses on stromal cells in lymphoid tissues, such as TAMs, fibroblastic reticular cells (FRCs), and follicular dendritic cells (FDCs). This review also focuses on the signal transduction caused by stromal cells and tumor cells via factors such as cytokines. IL-10 and other cytokines secreted by TAMs activate the JAK/STAT pathway in lymphoma cells of follicular lymphoma, classic Hodgkin lymphoma, and diffuse large B-cell lymphoma. FRCs play roles in tumor promotion in follicular lymphoma and diffuse large B-cell lymphoma. Cytokines/chemokines secreted by FDCs play essential roles in lymphoma cell survival, proliferation, invasion, and migration in follicular lymphoma. In conclusion, TAMs, FRCs, and FDCs play crucial roles in the TME of lymphomas. Furthermore, histological spatial analysis revealing the positional relationship of each cell could highlight lymphoma-stromal interactions.