Successful management of acute graft-versus-host disease with ibrutinib during cord blood transplantation for germline DDX41-mutated acute myeloid leukemia.

Background: Acute graft-versus-host disease (GVHD) is a major complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT) with significant morbidity and mortality, and efficacy of currently available therapeutics are limited. Acute and chronic GVHD are similar in that both are initiated by antigen presenting cells and activation of alloreactive B-cells and T-cells, subsequently leading to inflammation, tissue damage, and organ failure. One difference is that acute GVHD is mostly attributed to T-cell activation and cytokine release, whereas B-cells are the key players in chronic GVHD. Ibrutinib is an irreversible inhibitor of the Bruton's tyrosine kinase (BTK), which is part of B-cell receptor signaling. Ibrutinib is currently used for treating chronic GVHD, but its efficacy towards acute GVHD is unknown. Besides BTK, ibrutinib also inhibits interleukin-2 inducible T-cell kinase (ITK), which is predominantly expressed in T-cells and a crucial enzyme for activating the downstream pathway of TCR signaling. ITK activates PLCγ2 and facilitates signaling through NF-κB, NFAT, and MAPK, leading to activation and proliferation of T-cells and enhanced cytokine production. Therefore, the TCR signaling pathway is indispensable for development of acute GVHD, and ITK inhibition by ibrutinib would be a rational therapeutic approach. Case presentation: A 56-year-old male acute myeloid leukemia patient with Myeloid neoplasms with germline DEAD-box RNA helicase 41 (DDX41) mutation underwent cord blood transplantation and developed severe gastrointestinal (GI) acute GVHD which was refractory to steroids and mesenchymal stem cell therapy. While acute GVHD accommodated by multiple life-threatening GI bleeding events persisted, chronic cutaneous GVHD developed, and ibrutinib 420 mg/day was initiated from day 147 of transplant. Although ibrutinib was commenced targeting the chronic GVHD, unexpected and abrupt remission of acute GVHD along with remission of chronic GVHD was observed. Conclusion: Ibrutinib is a promising therapeutic for treating acute GVHD, and further studies are warranted.

Case report: Ensitrelvir for treatment of persistent COVID-19 in lymphoma patients: a report of two cases.

Persistent COVID-19 is a well recognized issue of concern in patients with hematological malignancies. Such patients are not only at risk of mortality due to the infection itself, but are also at risk of suboptimal malignancy-related outcomes because of delays and terminations of chemotherapy. We report two lymphoma patients with heavily pretreated persistent COVID-19 in which ensitrelvir brought about radical changes in the clinical course leading to rapid remissions. Patient 1 was on ibrutinib treatment for mantle cell lymphoma when he developed COVID-19 pneumonia which was severe and ongoing for 2 months despite therapy with molnupiravir, multiple courses of remdesivir, one course of sotrovimab, tocilizumab, and steroids. Patient 2 was administered R-CHOP therapy for diffuse large B-cell lymphoma when he developed COVID-19 which was ongoing for a month despite treatment with multiple courses of remdesivir and one course of sotrovimab. A 5-day administration of ensitrelvir promptly resolved the persistent COVID-19 accommodated by negative conversions of RT-qPCR tests in both patients within days. Ensitrelvir is a novel COVID-19 therapeutic that accelerates viral clearance through inhibition of the main protease of SARS-CoV-2, 3-chymotrypsin-like protease, which is vital for viral replication. Ensitrelvir is a promising treatment approach for immunocompromised lymphoma patients suffering from persisting and severe COVID-19.

Impact of non-driver gene mutations on thrombo-haemorrhagic events in ET patients.

Risk-adapted therapy is recommended to prevent major clinical complications, such as thrombo-haemorrhagic events, in patients with essential thrombocythaemia (ET). In this study, we analysed the association between non-driver gene mutations and thrombo-haemorrhagic events in 579 patients with ET. ASXL1 and TP53 mutations were frequently identified in patients with ET complicated by thrombosis (22.7% and 23.1%, respectively), and the DNMT3A mutation was frequently identified in patients who experienced haemorrhage (15.2%). Multivariate analyses of thrombosis-free survival (TFS) revealed that ASXL1 and TP53 mutations are associated with thrombosis (hazard ratio [HR] = 3.140 and 3.752 respectively). Patients harbouring the ASXL1 or TP53 mutation had significantly worse TFS rates than those without mutation (p = 0.002 and p < 0.001 respectively). Furthermore, JAK2V617F-mutated patients with accompanying ASXL1 mutations showed significantly shorter TFS compared with those without ASXL1 mutations (p = 0.003). Multivariate analyses of haemorrhage-free survival (HFS) revealed that the DNMT3A mutation (HR = 2.784) is associated with haemorrhage. DNMT3A-mutated patients showed significantly shorter HFS than those without the mutation (p = 0.026). Non-driver gene mutations should be considered in treatment strategies and may provide important information for personalised treatment approaches.

MPL gene mutation is a possible risk factor for thrombosis in patients with essential thrombocythemia in Japan.

OBJECTIVES: Since MPL mutation is a rare driver gene mutation found in a small number of essential thrombocythemia (ET) patients, the clinical characteristics of patients with MPL mutations and their association with thrombotic events have not yet been elucidated in Japan. METHODS: We enrolled 579 Japanese ET patients based on the diagnostic criteria of the WHO classification 2017 and compared clinical characteristics of MPL-mutated patients (n = 22; 3.8%) to JAK2V617F-mutated (n = 299; 51.6%), CALR-mutated (n = 144; 24.9%), and triple-negative (TN) (n = 114; 19.7%) patients. RESULTS: Thrombosis during follow up was observed in 4 out of 22 (18.2%) in the MPL-mutated group, which was the highest among all driver gene mutation groups (JAK2V617F-mutated, 8.7%; CALR-mutated, 3.5%; TN,1.8%). The MPL- and JAK2V617F-mutated groups had worse thrombosis-free survival (TFS) than the CALR-mutated (p = 0.043) and TN groups (p = 0.006). Univariable analysis revealed that a history of thrombosis was a possible risk factor for thrombosis among MPL-mutated patients (hazard ratio: 9.572, p = 0.032). CONCLUSIONS: MPL-mutated ET patients should require more intensive management to prevent recurrence of thrombosis.

Clinical characteristics of Japanese patients with myelodysplastic/myeloproliferative neoplasm with ring sideroblasts and thrombocytosis.

Myelodysplastic/myeloproliferative neoplasm with ring sideroblasts and thrombocytosis (MDS/MPN-RS-T) is a rare disease, which presents with features of myelodysplastic syndromes with ring sideroblasts and essential thrombocythemia, as well as anemia and marked thrombocytosis. SF3B1 and JAK2 mutations are often found in patients, and are associated with their specific clinical features. This study was a retrospective analysis of 34 Japanese patients with MDS/MPN-RS-T. Median age at diagnosis was 77 (range, 51-88) years, and patients had anemia (median hemoglobin: 9.0 g/dL) and thrombocytosis (median platelet count: 642 × 109/L). Median overall survival was 70 (95% confidence interval: 68-not applicable) months during the median follow-up period of 26 (range: 0-91) months. A JAK2V617F mutation was detected in 46.2% (n = 12) of analyzed patients (n = 26), while an SF3B1 mutation was detected in 87.5% (n = 7) of analyzed patients (n = 8). Like those with myelodysplastic syndromes or myeloproliferative neoplasms, patients often received erythropoiesis-stimulating agents and aspirin to improve anemia and prevent thrombosis. This study, which was the largest to describe the real-world characteristics of Japanese patients with MDS/MPN-RS-T, showed that the patients had similar characteristics to those in western countries.

Reevaluation of cardiovascular risk factors for thrombotic events in 580 Japanese patients with essential thrombocythemia.

Risk-adapted therapy is recommended to prevent thrombosis in essential thrombocythemia (ET) patients. An advanced age, a history of thrombosis, and the presence of the JAK2V617F mutation are well-defined risk factors for thrombosis in ET; however, the impact of cardiovascular risk (CVR) factors on thrombosis in ET remains elusive. Therefore, we herein investigated the impact of CVR factors on thrombosis in 580 ET patients who met the 2017 World Health Organization Classification diagnostic criteria. A univariate analysis identified hypertriglyceridemia and multiple CVR factors as strong risk factors for thrombosis (hazard ratio [HR] 3.530, 95% confidence interval [CI] 1.630-7.643, P = 0.001 and HR 3.368, 95% CI 1.284-8.833, P = 0.014, respectively) and hyper-LDL cholesterolemia as a potential risk factor (HR 2.191, 95% CI 0.966-4.971, P = 0.061). A multivariate analysis revealed that hypertriglyceridemia was an independent risk factor for thrombosis (HR 3.364, 95% CI 1.541-7.346, P = 0.002). Furthermore, poor thrombosis-free survival was observed in patients with a serum triglyceride level ≥ 1.2 mmol/L (HR = 2.592, P = 0.026 vs. < 1.2 mmol/L) or two or more CVR factors (P = 0.011 vs. no CVR factors and P = 0.005 vs. one CVR factor). These results revealed the impact of CVR factors on thrombosis in ET. Since CVR factors are manageable, lifestyle interventions, such as the control of serum triglyceride levels, may effectively prevent thrombosis in ET patients.

Non-driver gene mutation analysis in a large cohort of polycythemia vera and essential thrombocythemia.

OBJECTIVES: A proportion of patients with polycythemia vera (PV) and essential thrombocythemia (ET) harbor non-driver mutations associated with poor prognosis. In this study, we analyzed the frequency of non-driver mutations in a large Japanese PV and ET cohort. Furthermore, we studied the relationship of these mutations and prognosis in Japanese patients. METHODS: We enrolled 843 Japanese patients with PV or ET. Non-driver mutations were analyzed by target resequencing using next-generation sequencing. The association of the mutations with the prognosis was estimated using multivariable logistic regression analysis and log-rank test. RESULTS: Non-driver mutations were detected in 31.1% and 24.5% patients with PV and ET, respectively. Among them, ASXL1 mutations were identified as a risk factor for leukemic/myelofibrotic transformation in PV and ET patients (hazard ratio: 4.68, p = .006). The higher-risk groups of the mutation-enhanced international prognostic system (MIPSS)-PV and MIPSS-ET incorporating non-driver mutations exhibited significantly shorter overall survival compared with the low-risk group (p < .001). CONCLUSIONS: These results implicate the importance of studying non-driver mutations for predicting the prognosis and survival of Japanese PV and ET patients.

Adult paroxysmal cold hemoglobinuria following mRNA COVID-19 vaccination.

Paroxysmal cold hemoglobinuria (PCH) is an extremely rare subtype of autoimmune hemolytic anemia (AIHA) in adults. PCH is caused by the biphasic Donath-Landsteiner (DL) antibody which fixes complement to red blood cells at low temperatures and dissociates at warmer temperatures, leading to complement-mediated intravascular hemolysis. Autoimmune hematological disorders including AIHA and immune thrombocytopenia have been reported to develop following the mRNA COVID-19 vaccination. However, PCH developing subsequent to mRNA vaccination has never been reported. We report a 59-year-old male who developed PCH approximately a month after his second mRNA COVID-19 vaccination.

Abnormal Exacerbation of Moderately Differentiated Gastric Adenocarcinoma in a Patient with TAFRO Syndrome: An Impaired Tumor Immunity?

TAFRO syndrome is a relatively new disease entity first reported in 2010. We report a case of TAFRO syndrome accommodated by abnormal exacerbation of moderately differentiated gastric adenocarcinoma. The pathophysiology of TAFRO syndrome is largely unknown, but because the disease often responds to immunosuppressive therapy and also because T follicular helper (Tfh) cells are reported to be drastically decreased in TAFRO syndrome, involvement of a dysregulated immune system can be speculated. Growing evidence points toward a pivotal role of Tfh cells in tumor immunity through supporting ectopic lymphoid structures, which are recruitment sites for cells directly engaging in antitumor activity such as CD8+ T cells, NK cells, and macrophages. In fact, Tfh cells are reported to positively correlate with longer survival in human colorectal and breast cancer. Combined with our observations of hyperprogressive gastric cancer in the presented patient, an impaired tumor immunity is strongly indicated in TAFRO syndrome.

Cell-autonomous megakaryopoiesis associated with polyclonal hematopoiesis in triple-negative essential thrombocythemia.

A subset of essential thrombocythemia (ET) cases are negative for disease-defining mutations on JAK2, MPL, and CALR and defined as triple negative (TN). The lack of recurrent mutations in TN-ET patients makes its pathogenesis ambiguous. Here, we screened 483 patients with suspected ET in a single institution, centrally reviewed bone marrow specimens, and identified 23 TN-ET patients. Analysis of clinical records revealed that TN-ET patients were mostly young female, without a history of thrombosis or progression to secondary myelofibrosis and leukemia. Sequencing analysis and human androgen receptor assays revealed that the majority of TN-ET patients exhibited polyclonal hematopoiesis, suggesting a possibility of reactive thrombocytosis in TN-ET. However, the serum levels of thrombopoietin (TPO) and interleukin-6 in TN-ET patients were not significantly different from those in ET patients with canonical mutations and healthy individuals. Rather, CD34-positive cells from TN-ET patients showed a capacity to form megakaryocytic colonies, even in the absence of TPO. No signs of thrombocytosis were observed before TN-ET development, denying the possibility of hereditary thrombocytosis in TN-ET. Overall, these findings indicate that TN-ET is a distinctive disease entity associated with polyclonal hematopoiesis and is paradoxically caused by hematopoietic stem cells harboring a capacity for cell-autonomous megakaryopoiesis.

Intravascular large B-cell lymphoma as a recurrence of primary central nervous system lymphoma after chemotherapy: A case report.

We report about a 48-year-old woman diagnosed with primary central nervous system lymphoma (PCNSL). After chemotherapy and autologous stem cell transplantation, she presented with a continuous high-grade fever. Positron emission tomography-computed tomography revealed prominent hepatosplenomegaly and high diffuse uptake of 18F-fluorodeoxyglucose in the liver, spleen, and lungs. Intravascular large B-cell lymphoma (IVLBCL) was diagnosed using random skin biopsy. There were no symptoms of IVLBCL at the time of diagnosis of PCNSL. The histopathological features of PCNSL and IVLBCL were nearly similar. These findings suggest that IVLBCL was the recurrence of PCNSL rather than a separate entity.

High-grade Primary Central Nervous System Lymphomatoid Granulomatosis: Successful Rituximab Monotherapy.

The primary central nervous system (CNS) presentation of lymphomatoid granulomatosis (LYG) is rare, and no standard therapy for LYG with primary CNS symptoms exists. CNS-LYG patients usually survive for only less than a year from diagnosis. This is the first report of high-grade primary CNS-LYG with monoclonality that was successfully treated with rituximab monotherapy, resulting in a durable remission for more than 1 year in a 66-year-old woman with pemphigus vulgaris who was also on immunosuppressive therapy.

Clinical impacts of the mutational spectrum in Japanese patients with primary myelofibrosis.

Patients with primary myelofibrosis (PMF) have a poorer prognosis than those with other subtypes of myeloproliferative neoplasms (MPNs). To investigate the relationship between gene mutations and the prognosis of Japanese PMF patients, we analyzed mutations in 72 regions located in 14 MPN-relevant genes (CSF3R, MPL, JAK2, CALR, DNMT3A, TET2, EZH2, ASXL1, IDH1/2, SRSF2, SF3B1, U2AF1, and TP53) utilizing a target resequencing platform. In our cohort, ASXL1 mutations were more frequently detected in both overt and prefibrotic PMF patients than other mutations. The frequency of ASXL1 mutations was slightly higher among overt PMF patients than among prefibrotic PMF patients (44.6% vs 25.0%, FDR = 0.472). Decision tree classification algorithms revealed that ASXL1, EZH2, and SRSF2 mutations were associated with a poor prognosis for overt PMF. Overall survival was significantly shorter in patients harboring ASXL1, EZH2, or SRSF2 mutations than in those without these mutations (p = 0.03). These results suggest that, as reported in Western countries, MIPSS70 is applicable to Japanese PMF patients and ASXL1, EZH2, and SRSF2 mutations may be utilized as surrogate markers of a poor prognosis.

Significant role of magnetic resonance imaging for the diagnosis and evaluation of cardiac amyloidosis in primary light chain amyloidosis.

A 47-year-old male with macroglossia presented with dyspnea on effort and chest pain at rest. Cardiac MRI revealed diffuse global subendocardial late gadolinium enhancement below the left ventricular endocardium and a dark blood pool of intracardiac contrast medium. Tongue biopsy revealed amyloid deposition, which was limited in the myocardium. He was diagnosed with primary light chain amyloidosis. His condition was stage I according to the Mayo Clinic staging system. He underwent autologous peripheral blood stem cell transplantation. On Day 10, he developed chest pain and died suddenly on Day 11. Postmortem examination revealed amyloid deposition throughout the heart.

A Case of Primary Myelofibrosis in Which Ruxolitinib Therapy Ameliorated the Fibrosis, but Resulted in Fatty Marrow.

A 63-year-old woman was referred to our department in 2015 because of anemia and thrombocytosis. MPL W515/K was positive, JAK-2V617F and CALR exon 9 were negative. Bone marrow(BM)biopsy led to a diagnosis of primary myelofibrosis (PMF)in the prefibrotic/early stage(Grade 1). BMbiopsy performed in 2016 showed overt fibrotic stage(Grade 2). She was classified according to the Dynamic International Prognostic Scoring System(DIPSS)as intermediate(Int)-Ⅱrisk. Ruxolitinib 10 mg daily was initiated. Ruxolitinib was suspended for hepatic dysfunction after the dose was increased to 15 mg. Subsequently, ruxolitinib was resumed at 10 mg. BM biopsy performed in 2017 showed progression of myelofibrosis(MF)to Grade 3. BM biopsy performed in 2018 showed improved to Grade 0-1, however, BM was fatty. Currently in 2019, she continues to be on ruxolitinib. Results of immunohistochemical staining of BM biopsy specimens for cytokines and CD34 suggested the role of cytokines in the pathogenesis of the PMF. It was speculated that ruxolitinib blocked the production of cytokines to ameliorate the MF and restore the hematopoietic function of the BM. Although the pathogenesis of the fatty marrow remained unclear, the possibility of involvement of ruxolitinib cannot be denied.

Methotrexate-associated Hodgkin Lymphoma in a Patient with Rheumatoid Arthritis Successfully Treated with Brentuximab Vedotin in Combination with Doxorubicin, Vinblastine, and Dacarbazine (BV+AVD).

A 53-year-old woman had been diagnosed with rheumatoid arthritis (RA) in X-6. She was started on methotrexate (MTX) in X-1. She developed a cough, and chest computed tomography showed abnormalities. In X, MTX was discontinued, but the cough persisted. A lung biopsy revealed a diagnosis of nodular sclerosis classic Hodgkin lymphoma (CHL-NS). She was considered to have "other iatrogenic immunodeficiency-associated lymphoproliferative disorders" (OIIA-LPD), MTX-associated Hodgkin lymphoma (MTX-HL). She received six courses of brentuximab vedotin (BV) in addition to AVD (BV+AVD). A complete metabolic response was obtained, and the RA went into remission. This is the fourth reported case of BV+AVD for MTX-HL.