[Cold agglutinin disease: pathology, diagnosis, and treatment].

Cold agglutinin disease (CAD), an immune hemolytic disease mediated by the classical complement-dependent pathway, accounts for approximately 8% of autoimmune hemolytic anemia (AIHA) cases. Primary CAD is a clonal B-cell lymphoproliferative disease of the bone marrow that produces IgM type-M protein, while conventional secondary CAD is cold agglutinin syndrome (CAS). Clinical findings are broadly classified into chronic anemia due to hemolysis and symptoms associated with peripheral circulatory failure due to erythrocyte aggregation under cold exposure. Not all patients require drug therapy, but monoclonal antibody therapy against complement C1s is preferred for the former presentation and B-cell suppressors for the latter. As cold AIHA is treated differently than warm AIHA, misdiagnosis can significantly impact the outcome of treatment. The most important aspect of blood testing is temperature control of specimens. Cold agglutinin titer, IgM quantification, electrophoresis, and immunofixation methods may produce false-negative results if the serum is not temperature-controlled at 37-38°C until serum separation. Correct handling of specimens, along with knowledge of the various clinical features of CAD, will lead to correct diagnosis and appropriate treatment.

[Granulocyte-colony stimulating factor-producing multiple myeloma presenting with neutrophilia].

A 71-year-old woman complained of nausea and anorexia. Laboratory tests revealed significant neutrophilia and immunoglobulin A-kappa type M proteinemia, as well as increased plasma cells on bone marrow examination. Furthermore, the serum granulocyte-colony stimulating factor (G-CSF) concentration was high at 160 pg/ml, and the colony stimulating factor 3 receptor (CSF3R)-T618I mutation was negative. Immunohistochemical (IHC) analysis of bone marrow specimens using the anti-G-CSF antibody revealed immunopositivity of some myeloma cells. The patient was diagnosed using G-CSF-producing myeloma and was treated with daratumumab, lenalidomide, and dexamethasone. Her treatment resulted in a very good partial response, with normalization of both serum G-CSF levels and neutrophil count. There have been a few cases of G-CSF -producing myeloma reported, and it has previously been reported as chronic neutrophilic leukemia with M proteinemia. According to previous reports, techniques such as serum G-CSF measurements, IHC with an anti-G-CSF antibody, and CSF3R gene mutation analysis are useful for differentiating G-CSF-producing myeloma. However, the clinical characteristics and long-term prognosis of G-CSF-producing myeloma remain unknown. Additional case gathering and investigations are required.

Long-term outcomes and central nervous system relapse in extranodal natural killer/T-cell lymphoma.

To elucidate the long-term outcomes of non-anthracycline-containing therapies and central nervous system (CNS) events in patients with extranodal NK/T-cell lymphoma, nasal type (ENKTL), the clinical data of 313 patients with ENKTL diagnosed between 2000 and 2013 in a nationwide retrospective study in Japan were updated and analyzed. At a median follow-up of 8.4 years, the 5-year overall survival (OS) and progression-free survival (PFS) were 71% and 64%, respectively, in 140 localized ENKTL patients who received radiotherapy-dexamethasone, etoposide, ifosfamide, and carboplatin (RT-DeVIC) in clinical practice. Nine (6.4%) patients experienced second malignancies. In 155 localized ENKTL patients treated with RT-DeVIC, 10 (6.5%) experienced CNS relapse (median, 12.8 months after diagnosis). In five of them, the events were confined to the CNS. Nine of the 10 patients who experienced CNS relapse died within 1 year after CNS relapse. Multivariate analysis identified gingival (hazard ratio [HR], 54.35; 95% confidence interval [CI], 8.60-343.35) and paranasal involvement (HR, 7.42; 95% CI, 1.78-30.89) as independent risk factors for CNS relapse. In 80 advanced ENKTL patients, 18 received steroid (dexamethasone), methotrexate, ifosfamide, L-asparaginase, and etoposide (SMILE) chemotherapy as first-line treatment. Patients who received SMILE as their first-line treatment tended to have better OS than those who did not (p = 0.071). Six (7.5%) advanced ENKTL patients experienced isolated CNS relapse (median, 2.6 months after diagnosis) and died within 4 months of relapse. No second malignancies were documented in advanced ENKTL patients. In the entire cohort, the median OS after first relapse or progression was 4.6 months. 12 patients who survived 5 years after PFS events were disease-free at the last follow-up. Of those, 11 (92%) underwent hematopoietic stem cell transplantation. Our 8-year follow-up revealed the long-term efficacy and safety of RT-DeVIC and SMILE. The risk of CNS relapse is an important consideration in advanced ENKTL.

[Evaluation of the correlation between JAK2V617F allele burden by Quenching Probe-Tm method and allele-specific quantitative PCR method].

The JAK2V617F mutation is a driver mutation of myeloproliferative neoplasms (MPNs). V617F allele burden is considered a risk factor for complications associated with MPNs and is a predictor of prognosis. In Japan, V617F allele burden has been measured in laboratory settings using the i-densyTM IS-5320 genetic analyzer with the quenching probe-Tm (QP-Tm) method. However, since 2020, allele-specific quantitative PCR (AS-qPCR) is being performed in clinical settings for measuring V617F allele burden. To investigate the clinical usefulness of the QP-Tm method in patients with MPNs, we evaluated the V617F allele burden measured by both the methods. A good correlation was observed between the V617F allele burden determined using QP-Tm and that determined using AS-qPCR (P<0.001, rs=0.952). The median mutant allele burden, as determined using the QP-Tm method, was significantly higher in patients with polycythemia vera than in those with essential thrombocythemia. The results of this study suggested that the QP-Tm method will continue to be useful clinical ancillary test for measuring V617F allele burden.

[Thalassemia in Japan].

Thalassemia is caused by a reduced production of one globin chain due to a quantitative imbalance between the α-globin and non-α-globin chains that make up the hemoglobin. It is classified into α- and ß-thalassemia and characterized by microcytosis with polycythemia, and a Mentzer index of ≤13 aids in the diagnosis. In the genetic analysis of α-thalassemia, the Southeast Asian type was found to be the most common genetic subtype among Japanese and non-Japanese without a substantial difference. Conversely, the genetic analysis of ß-thalassemia revealed differences in the types and frequencies of mutations between Japanese individuals and foreigners living in Japan, with Japanese-specific mutations such as -31 A→G (TATA box). Acquired α-thalassemia exists in exceptional cases, and cases of myelodysplastic syndrome with acquired Hemoglobin H disease have been reported as α-thalassemia myelodysplastic syndrome. Recent trials using a novel therapeutic agent, luspatercept, for transfusion-dependent ß-thalassemia revealed that luspatercept safely and significantly reduces the transfusion volume.

Improved prognosis of extranodal NK/T cell lymphoma, nasal type of nasal origin but not extranasal origin.

Extranodal NK/T cell lymphoma (NKTCL), nasal type (ENKL) that shows no apparent nasal involvement, is termed extranasal NKTCL or non-nasal NKTCL. In this study, we aimed to explore therapeutic approaches and outcomes in patients with extranasal NKTCL in current clinical practice. A data set of patients with newly diagnosed NKTCL who were diagnosed at 31 institutes in Japan between 2000 and 2013 was used for analysis. The patients' fitness for steroid, methotrexate, ifosfamide, L-asparaginase, and etoposide (SMILE) chemotherapy was assessed using the major inclusion criteria of the SMILE phase 2 study. Of 358 patients, 47 (13%) had extranasal NKTCL. The most frequent extranodal sites of involvement in extranasal NKTCL were skin/subcutaneous tissue (n = 18). Six (13%) of the patients with extranasal NKTCL had localized disease and were diagnosed before 2010. With a median follow-up of 5.8 years, the 2-year overall survival (OS) in patients with nasal and extranasal NKTCL was 70% (95% confidence interval [CI], 65-75%) and 34% (95% CI, 21-47%), respectively. OS in patients with nasal NKTCL had a trend toward better according to treatment era (P = 0.063). In contrast, no obvious improvement of OS was observed in extranasal NKTCL (P = 0.43). The major inclusion criteria of the SMILE-P2 were met in 21% (10/47) of patients with extranasal NKTCL and 60% (188/311) of those with nasal NKTCL (P < 0.001). Despite the advent of new treatments for ENKL, OS remains unfavorable in extranasal NKTCL. A more effective therapy is needed for extranasal NKTCL.

[Red cell membrane disorders and thalassemia].

Congenital hemolytic anemias are classified into three major categories: red cell membrane disorders, hemoglobinopathies, and red cell enzyme disorders. The membrane disorders are caused by abnormalities in erythrocyte membrane proteins and are often associated with disease-specific deformations of red blood cells. Historically, membrane disorders have been classified according to morphology. In recent years, however, comprehensive genetic analysis with next-generation sequencing has been performed in patients with hemolytic anemia for whom making an accurate diagnosis is difficult. These studies have led to the identification of new causative genes, but there have been inconsistent associations in some cases between the diagnosed disease and the patient's clinical manifestations. Thalassemia is a hemoglobinopathy caused by a quantitative abnormality of one or the other of the globin chains in hemoglobin. Most Japanese patients with thalassemia have mild forms of the disease, which is different from reports in other countries. However, with globalization, the proportion of Japanese patients with intermediate or severe anemia is increasing. Therefore, it is incumbent on hematologists in Japan to be knowledgeable regarding prenatal diagnosis of and gene therapy for thalassemia.

[Relationship between Coombs-positive autoimmune hemolytic anemia and development of malignant tumors: a retrospective study].

Autoimmune hemolytic anemia (AIHA) is secondary to underlying diseases, such as autoimmune diseases and lymphoid malignancies. Recently, solid cancers have also been reported to be associated with AIHA, although there is not much information available. In this study, we retrospectively examined the correlation between AIHA and onset of malignancy in 100 patients diagnosed with AIHA based on the broad definition of AIHA at our hospital and cooperating institutions from January 1, 1995 to May 31, 2016. Malignancies were detected in 52 of the 100 patients (hematological malignancies: 39 patients; solid cancers: 22 patients; total malignancies including multiple primary malignancies: 67 patients). Of the 67 patients with malignancies, 28 were diagnosed with malignancies within 6 months of AIHA diagnosis. All patients with cold agglutinin disease (CAD) were associated with malignancies. Compared with warm AIHA, solid cancers were significantly more common among the patients with CAD. These findings emphasize the importance of investigating the malignancies upon diagnosis of AIHA.

A prospective multicenter phase II study of intrabone marrow transplantation of unwashed cord blood using reduced-intensity conditioning.

Cord blood transplantation (CBT) is associated with delayed hematopoietic recovery and graft failure. To overcome these problems, we conducted a prospective, multicenter phase II study of intrabone marrow transplantation in which patients received reduced-intensity conditioning without anti-thymocyte globulin (ATG). The primary endpoint was the probability of full donor engraftment. Forty patients with hematologic malignancies were enrolled. Cord blood (CB) cells were injected without washing into 4 iliac bone sites (2 at each hemipelvis), at which approximately 6 mL of CB was administered at one site with local anesthesia. Full donor engraftment rate was 86.8%. The cumulative incidence of neutrophil and platelet engraftment was 86.4% and 85.5%, respectively. The median time to neutrophil (>0.5 × 109 /L) and platelet (2.0 × 109 /L) recovery was 17.5 and 44 days, respectively. The probability of severe acute graft-vs-host disease (GVHD) was 47.5%. The cumulative incidence of extensive chronic GVHD was 3.0%. The probability of relapse and non-relapse mortality was 30.4% and 28.0%, respectively. The survival rate at 3 years was 45.6%, although most patients were at an advanced stage. These results suggest that our intrabone marrow-CBT procedure without using ATG improves hematopoietic recovery and decreases the incidence of chronic GVHD, but does not decrease the incidence of acute GVHD.

Sphingosine-1-phosphate receptor 1 as a prognostic biomarker and therapeutic target for patients with primary testicular diffuse large B-cell lymphoma.

Sphingosine-1-phosphate (S1P) is a potent lipid mediator that is produced during the metabolism of sphingolipid by sphingosine kinase. S1P has been implicated in the migration and trafficking of lymphocytes and several lymphoid malignancies through S1P receptors. Moreover, the overexpression of sphingosine-1-phosphate receptor 1 (S1PR1) has been correlated with the constitutive activation of signal transducer and activator of transcription (STAT)3 and poor prognosis of diffuse large B-cell lymphoma (DLBCL). Thus, in this study, we examined the expression of S1PR1 in 198 DLBCL samples collected from nodal and various extranodal sites and sub-classified formalin-fixed paraffin-embedded tissue samples into germinal centre B-cell-like (GCB) and non-GCB subgroups using immunohistochemistry. These analyses showed S1PR1 overexpression in 15·7% of all cases with DLBCL and in 54·2% of 24 cases with primary testicular (PT)-DLBCL; S1PR1 expression correlated with S1PR1mRNA expression and STAT3 phosphorylation in fresh samples. Analyses of data from a single institution suggested that S1PR1 overexpression was an independent negative prognostic marker in 68 patients with DLBCL of clinical stages I and II. The present high prevalence of S1PR1 overexpression warrants the consideration of PT-DLBCL as a distinct disease subtype and suggests the potential of the S1P/S1PR1 axis as a therapeutic target.

[Correlation between serum L-carnitine concentration and neutrophil engraftment in patients treated with cord blood transplantation].

In cord blood transplantation (CBT), the amount of time elapsing until hematological engraftment has effects on the transplantation results. Carnitine deficiency has been reported to cause erythropoietin refractory anemia in chronic hemodialysis patients and thrombocytopenia or leukopenia of cirrhosis, and carnitine supplementation can improve hematopoiesis in patients with hepatic or renal failure. Patients who receive CBT may suffer from carnitine deficiency, but no studies have investigated the carnitine status of such patients. Herein, we determined the concentration of free carnitine (FC) and investigated the correlation between FC and engraftment in patients who received CBT. Twenty-three patients who received CBT at our hospital during the period from April 2013 to January 2015 were enrolled in this study. One patient was excluded because of graft failure, such that 22 patients were ultimately evaluable. FC concentrations of the patients were sequentially monitored at 4 time points (before conditioning therapy, day 0, day 7, and day 14), basic laboratory data were collected, and their correlations with engraftment were analyzed. FC concentrations of the patients were generally low (before conditioning therapy: 33.1, day 0: 43.2, day 7: 38.3, and day 14: 37.8 µmol/l). Significant inverse correlations were observed between FC concentrations and the number of days required for neutrophil engraftment on day 0 and day 14 (before conditioning therapy: P=0.15, r=-0.33, day 0: P=0.04, r=-0.43, day 7: P=0.30, r=-0.23, and day 14: P=0.01, r=-0.55). These results suggest carnitine to be an important nutrient that promotes hematopoietic recovery after CBT.

[Performance Assessment of a Newly Developed Rapid Diagnostic Reagent for Human Immunodeficiency Virus].

Extremely early diagnosis of human immunodeficiency virus (HIV) infection has been considered highly important for its treatment. We conducted a performance assessment of a newly developed rapid diagnostic reagent for HIV by using a fourth-generation immunochromatographic assay (Alere HIV Combo). We used whole-blood, plasma, and serum samples obtained from 250 Japanese adults who visited the Kawasaki Medical School Hospital and underwent HIV screening tests. We also used 12 types of commercial HIV-1 sero- conversion panels and World Health Organization standard antigens. This method, which has a detection sensitivity of 100% and a specificity of 99.3%, was as accurate as the chemiluminescent immunoassay (CLIA) method. In a sensitivity test using seroconversion panels in the early phase of infection, the mean duration until positive conversion was 19.3 days. With this method having a high detection sensitivity for HIV-1p24 antigen, the results from whole-blood samples were the same as those from plasma and serum samples. Therefore, it can be considered as a useful rapid measurement method for general practice.

[Hereditary red cell membrane disorders in Japan: comparison with other countries].

Red cell membrane disorders are the most common type of inherited hemolytic disorders in the Japanese population. In hereditary spherocytosis (HS), the primary presentation is a loss of membrane surface area, leading to reduced deformability because of defects in the membrane proteins ankyrin, band 3, ß-spectrin, α spectrin, or protein 4.2 (P4.2). Complete P4.2 deficiencies, which are inherited in an autosomal recessive manner, comprise a unique HS subgroup and are common in Japanese, but rare in other populations. In contrast, the principle presentation in hereditary elliptocytosis (HE) is mechanical weakness of the erythrocyte membrane skeleton due to defects in α-spectrin, ß-spectrin, or protein 4.1. Although α-spectrin mutations are the most frequent cause of HE in Caucasian, African, and Mediterranean populations, these mutations are rare in the Japanese population, in which P4.1 deficiencies are instead most common. Furthermore, hereditary stomatocytoses (HSt) are disorders of monovalent cation permeability in the red cell membrane.

[Band 3 deficiency as a cause of hereditary spherocytosis].

Band 3 protein accounts for the largest percentage of whole erythrocyte membrane proteins. Abnormalities in this protein are closely associated with pathologies including hereditary spherocytosis (HS), Southeast Asian ovalocytosis and distant renal tubular acidosis. Currently, EMA binding capacity measurement in erythrocytes is the most useful screening test for diagnosing HS. We have also demonstrated reduced EMA binding capacity in patients with HS who have deficiencies of membrane proteins such as ankyrin not directly binding to EMA and who have as yet undetectable abnormalities of membrane proteins. However, even patients with hereditary elliptocytosis, who have a partial spectrin deficiency, were found to show reduced EMA binding capacity. Six of 7 had spherocytic elliptocytosis. Therefore, it is necessary to meticulously diagnose HS by ruling out all other possibilities.

HIV-associated CD8+ T-cell Skin Infiltrative Disease and EBV-associated Polymorphic B-cell Lymphoproliferative Disorder in an AIDS Patient Who Improved Dramatically with Antiretroviral Therapy Alone.

Human immunodeficiency virus (HIV)-associated CD8+ T-cell skin infiltrative disease with severe erythroderma has rarely been reported. While HIV-positive patients are prone to develop lymphoma, which is often associated with Epstein-Barr virus, polymorphic lymphoproliferative disorder is rare, accounting for <5% of cases. We herein report a 41-year-old HIV-positive man who presented with a fever, erythroderma, and lymphadenopathy and was diagnosed with the coexistence of both diseases. His condition improved significantly with continued antiretroviral therapy. This case suggests that HIV-induced immunodeficiency is central to the pathogenesis of both entities and that improvement of the immunodeficient state is an effective treatment.

A case of hepatitis E that developed during chemotherapy for malignant lymphoma and responded to ribavirin.

BACKGROUND: The main differences in cases of sudden elevation of hepatic enzyme levels during immunochemotherapy are the reactivation of the hepatitis B virus or drug-induced liver injury. Here, we report a case of acute liver injury caused by the hepatitis E virus (HEV) during chemotherapy for malignant lymphoma, wherein the patient was successfully treated for the hepatitis and resumed chemotherapy to completion. CASE: A 57-year-old woman visited her local doctor because she felt lightweight and tired. The patient underwent lower gastrointestinal endoscopy and was diagnosed with a malignant lymphoma of the small intestine (diffuse large B-cell lymphoma). The patient had a history of oral consumption of undercooked pork liver to improve anemia and was diagnosed with acute hepatitis E. CONCLUSION: This report highlights the successful treatment of HEV infection in a patient undergoing immunosuppressive therapy for malignant lymphomas. A novel aspect of this study is the safe and effective use of ribavirin, an antiviral medication, along with continued chemotherapy, which resulted in sustained virological response (SVR) and the completion of the planned chemotherapy regimen. This report also provides new insights into the management of HEV infections in immunosuppressed patients undergoing chemotherapy and emphasizes the importance of considering HEV as a potential cause of acute liver injury in such cases. The successful use of ribavirin along with continued chemotherapy offers a promising treatment strategy for clinicians to consider in similar scenarios.

JAK2 V617F Mutation and Large Cerebral Artery Disease in Patients with Myeloproliferative Neoplasms.

AIM: The aim of the present study was to clarify the association between the Janus kinase 2 (JAK2) V617F mutation and large cerebral artery disease (LCAD) in patients with myeloproliferative neoplasms (MPNs). METHODS: We retrospectively analysed patients diagnosed with MPNs between June 1992 and June 2022 who underwent brain magnetic resonance imaging. LCAD was defined as extracranial or intracranial large artery stenosis (≥ 50%) or occlusion on magnetic resonance angiography. RESULTS: A total of 86 patients (47 males; median age, 69 years old) were enrolled in this study. JAK2 V617F mutation was detected in 63 (73.3%) patients and LCAD in 35 (40.7%) patients. Univariate analysis showed that history of ischaemic stroke (LCAD, 62.9% vs. non-LCAD, 11.8%; P＜0.001), JAK2 V617F mutation (91.4% vs. 60.8%, P=0.002), and age ≥ 60 years (85.7% vs. 60.8%, P=0.016) were significantly associated with LCAD. Multiple logistic regression analysis showed that, in addition to ischaemic stroke, age ≥ 60 years and diabetes mellitus, JAK2 V617F mutation (odds ratio 29.2, 95% confidence interval 1.2-709.8, P=0.038) was independently associated with LCAD. LCAD was frequently observed in the intracranial carotid (14/35, 40.0%) and middle cerebral (13/35, 37.1%) arteries. CONCLUSIONS: This study revealed a significant association between the JAK2 V617F mutation and LCAD in patients with MPNs. This suggests that the JAK2 V617F mutation may promote cerebrovascular atherosclerosis and could be very important in determining therapeutic strategies for patients with not only JAK2 V617F-mutated MPNs but also LCAD-related stroke.