Two novel high-risk adult B-cell acute lymphoblastic leukemia subtypes with high expression of CDX2 and IDH1/2 mutations.

The genetic basis of leukemogenesis in adults with B-cell acute lymphoblastic leukemia (B-ALL) is largely unclear, and its clinical outcome remains unsatisfactory. This study aimed to advance the understanding of biological characteristics, improve disease stratification, and identify molecular targets of adult B-ALL. Adolescents and young adults (AYA) (15 to 39 years old, n = 193) and adults (40 to 64 years old, n = 161) with Philadelphia chromosome-negative (Ph-) B-ALL were included in this study. Integrated transcriptomic and genetic analyses were used to classify the cohort into defined subtypes. Of the 323 cases included in the RNA sequencing analysis, 278 (86.1%) were classified into 18 subtypes. The ZNF384 subtype (22.6%) was the most prevalent, with 2 novel subtypes (CDX2-high and IDH1/2-mut) identified among cases not assigned to the established subtypes. The CDX2-high subtype (3.4%) was characterized by high expression of CDX2 and recurrent gain of chromosome 1q. The IDH1/2-mut subtype (1.9%) was defined by IDH1 R132C or IDH2 R140Q mutations with specific transcriptional and high-methylation profiles. Both subtypes showed poor prognosis and were considered inferior prognostic factors independent of clinical parameters. Comparison with a previously reported pediatric B-ALL cohort (n = 1003) showed that the frequencies of these subtypes were significantly higher in AYA/adults than in children. We delineated the genetic and transcriptomic landscape of adult B-ALL and identified 2 novel subtypes that predict poor disease outcomes. Our findings highlight the age-dependent distribution of subtypes, which partially accounts for the prognostic differences between adult and pediatric B-ALL.

Significance of absolute neutrophil count before allogeneic hematopoietic stem cell transplantation in adult patients with aplastic anemia.

The impact of absolute neutrophil count (ANC) before allogenic hematopoietic stem cell transplantation (HSCT) on the outcomes for patients with aplastic anemia (AA) remains unclear. We retrospectively evaluated the relationship between ANC before transplantation and patient outcomes, involving 883 adult Japanese patients with AA who underwent allogeneic HSCT as their first transplantation between 2008 and 2020. Patients were divided into three groups based on ANC: 0/µL (n = 116); 1-199 (n = 210); and ≥ 200 (n = 557). In the low ANC groups (ANC < 200), patient age was higher, previous anti-thymocyte globulin (ATG) treatments were infrequent, duration from diagnosis to transplantation was shorter, hematopoietic cell transplantation-comorbidity index (HCT-CI) was higher, ATG-based conditioning was used infrequently, and peripheral blood stem cell from related donor and cord blood were used frequently. In multivariate analysis, patient age, previous ATG treatment, HCT-CI, stem cell source, and ANC before transplantation were significantly associated with 5-year overall survival (OS) ("ANC ≥ 200": 80.3% vs. "ANC 1-199": 71.7% vs. "ANC 0": 64.4%). The cumulative incidence of bacterial infection, invasive fungal disease, and early death before engraftment were significantly higher in the low ANC groups. Among patients with ANC of zero before transplantation, younger patient age, shorter duration from diagnosis to transplantation, HCT-CI of 0, and bone marrow from related donor as stem cell source were significantly associated with better OS. Consequently, ANC before allogeneic HSCT was found to be a significant prognostic factor in adult patients with AA. Physicians should pay attention to ANC before transplantation.

Clinical utility of genomic profiling of AML using paraffin-embedded bone marrow clots: HM-SCREEN-Japan 01.

Next-generation sequencing of AML has identified specific genetic mutations in AML patients. Hematologic Malignancies (HM)-SCREEN-Japan 01 is a multicenter study to detect actionable mutations using paraffin-embedded bone marrow (BM) clot specimens rather than BM fluid in AML patients for whom standard treatment has not been established. The purpose of this study is to evaluate the presence of potentially therapeutic target gene mutations in patients with newly diagnosed unfit AML and relapsed/refractory AML (R/R-AML) using BM clot specimens. In this study, 188 patients were enrolled and targeted sequencing was undertaken on DNA from 437 genes and RNA from 265 genes. High-quality DNA and RNA were obtained using BM clot specimens, with genetic alterations successfully detected in 177 patients (97.3%), and fusion transcripts in 41 patients (23.2%). The median turnaround time was 13 days. In the detection of fusion genes, not only common fusion products such as RUNX1-RUX1T1 and KMT2A rearrangements, but also NUP98 rearrangements and rare fusion genes were observed. Among 177 patients (72 with unfit AML, 105 with R/R-AML), mutations in KIT and WT1 were independent factors for overall survival (hazard ratio = 12.6 and 8.88, respectively), and patients with high variant allele frequency (≥40%) of TP53 mutations had a poor prognosis. As for the detection of actionable mutations, 38% (n = 69) of patients had useful genetic mutation (FLT3-ITD/TKD, IDH1/2, and DNMT3AR822 ) for treatment selection. Comprehensive genomic profiling using paraffin-embedded BM clot specimens successfully identified leukemic-associated genes that can be used as therapeutic targets.

Significance of alveolar nitric oxide concentration in the airway of patients with organizing pneumonia after allogeneic hematopoietic stem cell transplantation.

Organizing pneumonia (OP) is a complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT) and a manifestation of peripheral airway/alveolar inflammation. Recently, alveolar nitric oxide concentration (Calv) has been revealed as a noninvasive marker of peripheral airway inflammation; however, whether Calv levels are associated with OP and peripheral airway in patients after allo-HSCT remains unclear. Herein, we evaluated whether Calv levels could reflect the presence of OP and structural airway changes in patients after allo-HSCT. We measured the eNO levels of 38 patients (6 with OP and 32 without OP) who underwent allo-HSCT. Three-dimensional computed tomography (CT) analysis of the airway was performed in 19 patients. We found that in patients with OP, Calv levels were significantly higher than in those without OP (10.6 vs. 5.5 ppb, p < 0.01). Receiver-operating characteristic analyses revealed a Calv cut-off value for OP detection of 10.2 ppb. No significant differences in the patient characteristics, except for the presence of OP (p < 0.01), were noted between the two groups stratified by the Calv cut-off value. Three-dimensional CT images of the airway revealed gradually increasing positive correlations between Calv levels and airway wall area of the third-, fourth-, and fifth-generation bronchi (r = 0.20, 0.31, 0.38; p = 0.42, 0.19, 0.038, respectively), indicating that Calv levels are strongly correlated with the wall thickness of the distal bronchi. Our results suggest that the Calv level may be a useful noninvasive detectable marker for OP after an allo-HSCT.

Total body irradiation-containing conditioning regimens without antithymocyte globulin in adults with aplastic anemia undergoing umbilical cord blood transplantation.

Thus far, there have been no large cohort studies on total body irradiation (TBI)-containing conditioning regimens without antithymocyte globulin (ATG) in adults with aplastic anemia (AA) undergoing umbilical cord blood (UCB) transplantation (UCBT). We retrospectively analyzed 115 adults with idiopathic AA undergoing UCBT using TBI-containing reduced-intensity conditioning (RIC) regimens without ATG between 2000 and 2018 on behalf of the Adult Aplastic Anemia Working Group of the Japanese Society for Hematopoietic Cell Transplantation. We then compared transplantation outcomes between a fludarabine (Flu)- and melphalan (Mel)-based regimen (FM) and a Flu- and cyclophosphamide (Cy)-based regimen (FC). The median patient age at UCBT was 41 years. The median total nucleated cell and total CD34+ cell doses in a UCB unit at cryopreservation were 2.5 × 107/kg and 0.7 × 105/kg, respectively. The median follow-up period for survivors was 47 months. The cumulative incidence rate of neutrophil engraftment was 76.5%, and the 4-year overall survival (OS) rate was 64.3%. In multivariate analysis, the covariates that were significantly associated with a higher neutrophil engraftment were total CD34+ cell dose in an UCB unit (≥ 0.7 × 105/kg; hazard ratio, 0.57, P = 0.01) and total dose of TBI (4 Gy of TBI; hazard ratio, 0.32, P = 0.01). There was no significant difference in the cumulative incidence of neutrophil engraftment and the 4-year OS between the FM and FC groups. In conclusion, TBI-containing RIC regimens without ATG are suitable for adults with AA undergoing UCBT. There were no significant differences in transplantation outcomes between the FM and FC groups.

Prognostic Impact of Donor Source on Allogeneic Hematopoietic Stem Cell Transplantation Outcomes in Adults with Chronic Myelomonocytic Leukemia: A Nationwide Retrospective Analysis in Japan.

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a curative therapeutic option for patients with chronic myelomonocytic leukemia (CMML). We retrospectively compared the post-transplantation outcomes of 159 patients with CMML who underwent allo-HSCT using 4 types of donor sources: HLA-matched related donor graft, unrelated bone marrow (U-BM), unrelated cord blood (U-CB), and HLA-mismatched related donor graft. The median patient age at allo-HSCT was 54 years (range, 16 to 75 years). In multivariate analyses, the use of HLA-matched related donor grafts correlated with better overall survival than U-BM (hazard ratio [HR], 2.05; 95% confidence interval [CI], 1.21 to 3.48; P = .008), U-CB (HR, 3.80; 95% CI, 2.07 to 6.95; P < .001), or HLA-mismatched related donor grafts (HR, 6.18; 95% CI, 2.70 to 14.15; P < .001). Mortality after the relapse or progression of CMML did not significantly differ among the 4 types of donor source. Transplantation-related mortality was highest in recipients of U-CB (HR, 3.32; 95% CI, 1.33 to 8.26; P = .010). In patients with CMML, allo-HSCT using an alternative donor may contribute to durable remission; however, further improvements in transplantation-related mortality are required for this type of transplantation.

[Refractory primary immune thrombocytopenia in pregnancy requiring splenectomy and repeated intravenous immunoglobulin therapy].

A 30-year-old primigravid woman without a history of thrombocytopenia was referred to our hospital because of severe thrombocytopenia (<1,000 thrombocytes/µl) at 16 weeks of gestation and diagnosed with idiopathic thrombocytopenic purpura (ITP). There was no improvement in the platelet count after treatment with 0.5-1.0 mg/kg/day prednisolone, and the 400 mg/day intravenous immunoglobulin (IVIg) administered for 5 days gradually became ineffective; therefore, a laparoscopic splenectomy was performed at 25 weeks of gestation. The increase in the platelet count after the splenectomy was temporary, but the effects of IVIg therapy improved, and the patient received IVIg therapy seven times in total during her pregnancy. Her platelet count ranged between 10,000 and 70,000/µl after the splenectomy, compared with <5,000/µl before the surgery. The patient underwent an elective cesarean section at 34 weeks of gestation without any significant bleeding. The baby was diagnosed with thrombocytopenia at birth (34,000 thrombocytes/µl) and was administered only one dose of IVIg, which increased the baby's platelet count to a normal level after 14 days. The patient's platelet count also increased after delivery. Splenectomy and repeated IVIg therapy can be considered for refractory severe ITP during pregnancy.

D816 mutation of the KIT gene in core binding factor acute myeloid leukemia is associated with poorer prognosis than other KIT gene mutations.

The clinical impact of KIT mutations in core binding factor acute myeloid leukemia (CBF-AML) is still unclear. In the present study, we analyzed the prognostic significance of each KIT mutation (D816, N822K, and other mutations) in Japanese patients with CBF-AML. We retrospectively analyzed 136 cases of CBF-AML that had gone into complete remission (CR). KIT mutations were found in 61 (45%) of the patients with CBF-AML. D816, N822K, D816 and N822K, and other mutations of the KIT gene were detected in 29 cases (21%), 20 cases (15%), 7 cases (5%), and 5 cases (4%), respectively. The rate of relapse-free survival (RFS) and overall survival (OS) in patients with D816 and with both D816 and N822K mutations was significantly lower than in patients with other or with no KIT mutations (RFS: p < 0.001, OS: p < 0.001). Moreover, stratified analysis of the chromosomal abnormalities t(8;21)(q22;q22) and inv(16)(p13.1q22), t(16;16)(p13.1;q22) showed that D816 mutation was associated with a significantly worse prognosis. In a further multivariate analysis of RFS and OS, D816 mutation was found to be an independent risk factor for significantly poorer prognosis. In the present study, we were able to establish that, of all KIT mutations, D816 mutation alone is an unfavorable prognostic factor.

Effects of human herpesvirus 6B reactivation on cognitive function in cord blood transplant recipients: a prospective multicenter study.

This prospective multicenter study aimed to determine the effects of human herpesvirus-6B (HHV-6B) reactivation on central nervous system (CNS) function in cord blood transplant (CBT) recipients. Our focus was to track HHV-6B reactivation and evaluate its association with delirium and cognitive function, specifically in the domains of verbal memory, attention/processing speed, and quality of life (QOL). A cohort of 38 patients participated in this study. Of the 37 patients evaluated, seven (18.9%) developed delirium, with six of these cases emerging after HHV-6B reactivation (median lag, 7 days). Evaluation of verbal memory showed that the final trial score for unrelated words at 70 days after transplantation was significantly lower than that before preconditioning (P = 0.004) among patients (n = 15) who experienced higher-level HHV-6B reactivation (median or higher maximum plasma HHV-6 DNA load for participating patients). Patients without higher-level reactivation did not show significant declines in verbal memory scores. QOL was assessed using the 36-item Short-Form Health Survey, and the social functioning score 1 year post-transplantation was significantly lower in patients who experienced higher-level HHV-6B reactivation than in those who did not. Our findings suggest that higher-level HHV-6B reactivation can detrimentally affect certain cognitive functions in CBT recipients.

Prognosis of patients with core binding factor acute myeloid leukemia after first relapse.

Core binding factor acute myeloid leukemia is known to have a favorable prognosis, however, there have been no detailed analyses on prognostic factors after first relapse. Using a nationwide database, we retrospectively analyzed core binding factor acute myeloid leukemia patients who relapsed after being treated with chemotherapy alone during their first complete remission. Of a total of 397 patients who were diagnosed with core binding factor acute myeloid leukemia, 208 experienced a first relapse, and analyses were performed in 139 patients for whom additional data were available. In the entire cohort, the overall survival rate after relapse was 48% at 3 years. By multivariate analysis, younger age at diagnosis, a longer interval before relapse, and inv(16) were shown to be independently associated with better survival after relapse. Although there was no significant difference in survival after relapse between patients who underwent allogeneic hematopoietic cell transplantation and those who did not in the overall series of relapsed patients, we found that transplantation significantly improved survival among patients who had t(8;21) (54% versus 26% at 3 years, P=0.002). In addition, among patients with t(8;21), those who had different cytogenetics at relapse had a significantly improved survival after transplantation, while those who had same cytogenetics did not. We showed that the prognosis differs significantly and optimal treatment strategies may vary between groups of patients with core binding factor acute myeloid leukemia with different cytogenetic profiles at relapse. These findings may help to guide therapeutic decisions after first relapse.

Outcome of peripheral blood stem cell transplantation from HLA-identical sibling donors for adult patients with aplastic anemia.

Although bone marrow transplantation is the recommended form of allogeneic hematopoietic stem cell transplantation for aplastic anemia, some patients undergo peripheral blood stem cell transplantation (PBSCT). Therefore, there is critical demand to identify factors affecting transplantation outcomes. Using the Japanese registry database, we retrospectively analyzed outcomes of 94 adult patients with aplastic anemia who underwent PBSCT from HLA-identical sibling donors. The cumulative incidence of neutrophil engraftment was 94% (95% confidence interval [CI] 86-97%), and was significantly higher in patients who received anti-thymocyte globulin (ATG) in conditioning. The cumulative incidence rate was 26% (95% CI 17-35%) in grades II-IV acute graft-versus-host disease (GVHD) and 20% (95% CI 13-29%) in extensive chronic GVHD, and tended to be lower in patients with chronic GVHD who received ATG-based conditioning. The 5-year overall survival (OS) rate was 70% (95% CI 59-78%). In multivariate analysis, patient age < 40 years, shorter period from diagnosis to transplantation, better performance status, and ATG-based conditioning were significantly correlated with favorable OS. In conclusion, PBSCT from HLA-identical sibling donors for aplastic anemia would result in acceptable outcomes. Several risk factors identified in our study should be considered when selecting a stem cell source.

[Allogeneic hematopoietic stem cell transplantation with fludarabine, melphalan, and total body irradiation as a conditioning for elderly patients with myeloid malignancies].

A variety of reduced-intensity conditionings have been used in the reported studies of allogeneic hematopoietic stem cell transplantation (HSCT) for elderly patients with myeloid hematological malignancies. This study retrospectively analyzed the outcome of allogeneic HSCT for 10 patients aged 50 years or older with myeloid hematological malignancies after conditioning with fludarabine (125 mg/m(2)), melphalan (140 mg/m(2)) and total body irradiation (TBI; 8 Gy). Median age of the patients was 56.5 years, and diagnoses included acute myelogenous leukemia, advance myelodysplastic syndrome, and secondary myelofibrosis. Sources of stem cells were bone marrow from sibling (n=4) or unrelated donor (n=6). Both overall and disease-free survival rates were 40.0% (95% CI: 10.6~69.4%). Causes of death were relapse (n=2), fungal infection (n=2), and secondary malignancies (n=2). Because of a high incidence of transplant-related mortality, further refinement of this conditioning is required.

Retrospective Analysis of Autologous Stem Cell Transplantation for AL Amyloidosis: A Study from the Multiple Myeloma Working Group of the Japan Society for Hematopoietic Cell Transplantation.

Autologous stem cell transplantation (ASCT) is the standard of care for eligible patients with light-chain (AL) amyloidosis, but little is known about it in Asian populations. To investigate the outcome of and prognostic factors for ASCT, we retrospectively analyzed ASCT cases registered to the Transplant Registry Unified Management Program between December 1999 and December 2015, with extra clinical information collected through a secondary survey. The primary endpoint was overall survival (OS). Hematologic response, organ response, and transplantation-related mortality were analyzed as secondary endpoints. The database search identified 330 patients (median age, 57 years; range, 31 to 74), and the secondary survey provided details for the 110 patients (33.3%) included in the study cohort. Fewer than 3 organs were involved in 56.4% of the patients, with cardiac involvement in 57.3%. Performance status (PS) was 0 to 1 in 83.6%. The conditioning melphalan dose was reduced in 54.6%. Overall hematologic response was a partial response or better in 77.6% of the patients and a complete response in 49.3%. The 5-year OS was 70.1%. A PS of 0 to 1 was associated with a significantly better prognosis in terms of OS. Although survival after ASCT for AL amyloidosis improved over time, poor PS and cardiac involvement had negative impacts on prognosis. The early mortality after ASCT was 6.4%. Poor PS and cardiac involvement led to high early mortality. A brain natriuretic peptide (BNP) level of 400 pg/mL was associated with worse OS. Our study has several limitations inherent to a retrospective analysis using a questionnaire. The depth of response and biomarker responses were significantly limited by the degree of missing data. Nonetheless, our data support the importance of careful patient selection for good outcomes of ASCT in patients with AL amyloidosis. In our cohort, poor PS and cardiac involvement had a negative impact on prognosis, and BNP level was a useful prognostic factor.

Soluble Interleukin-2 Receptor Index Predicts Outcomes After Cord Blood Transplantation.

BACKGROUND: Our previous study demonstrated that the soluble interleukin-2 receptor (sIL-2R) index, defined as the ratio of serum sIL-2R levels at neutrophil engraftment to that before conditioning, is a biomarker that can predict acute graft-vs-host disease (GVHD) after unrelated bone marrow transplantation. In the present study, we evaluated the significance of the sIL-2R index among patients who underwent cord blood transplantation (CBT). METHODS: We retrospectively analyzed 31 patients who underwent single-unit CBT as their first transplantation for hematologic malignancies. RESULTS: The median sIL-2R index was 4.2. The cumulative incidence of grade II to IV acute GVHD was not associated with the sIL-2R index. However, the cumulative incidence of relapse at 3 years after transplantation was significantly lower, with an sIL-2R index ≥ 3.7 than with an index < 3.7 (12.8% vs 50.0%; P = .04). As a result, the probability of overall survival at 3 years after transplantation was significantly higher in the former group than in the latter (79.8% vs 20.0%; P < .01). Only the dose of corticosteroid administered in the pre-engraftment period influenced the sIL-2 index. CONCLUSION: The sIL-2R index can predict the incidence of relapse and probability of survival after CBT, possibly reflecting a graft-vs-leukemia effect.

Outcome of allogeneic hematopoietic stem cell transplantation in adult patients with paroxysmal nocturnal hemoglobinuria.

The safety and efficacy of allogeneic hematopoietic stem cell transplantation (HSCT) for paroxysmal nocturnal hemoglobinuria (PNH) remain unclear. Therefore, we retrospectively analyzed the outcomes of 42 adult patients with PNH who underwent allogeneic HSCT using the registry database of the Japan Society for Hematopoietic Cell Transplantation. The median patient age was 32.5 years. The number of packed red cell (PRC) transfusions was < 20 times in 19 patients and ≥ 20 times in 16; 7 patients had missing data. Stem cell sources were bone marrow (N = 15) or peripheral blood (N = 13) from a related donor or bone marrow (N = 11) and cord blood (N = 3) from an unrelated donor. The cumulative incidence of neutrophil engraftment at day 40 was 81%. Six patients died before engraftment, and the 6-year overall survival (OS) was 74%. The OS of patients with < 20 pretransplant PRC transfusions was significantly higher than that of patients with ≥ 20 pretransplant PRC transfusions (95% vs. 63%; P < 0.05). Moreover, the OS of patients aged < 30 years was significantly higher than that of patients aged ≥ 30 years (90% vs. 59%; P < 0.05). Allogeneic HSCT for PNH could provide favorable survival; however, pretransplant transfusion burden and patient age should be considered when deciding the timing of allogeneic HSCT.

TERT and JAK2 polymorphisms define genetic predisposition to myeloproliferative neoplasms in Japanese patients.

Myeloproliferative neoplasms (MPNs), including polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF), are often characterized by specific somatic mutations in any of the three genes: JAK2, CALR, or MPL. A single nucleotide polymorphism (SNP), rs2736100, in the reverse transcriptase gene (TERT) and a germline JAK2 46/1 haplotype have been associated with MPNs in North American and European patients. We examined 201 Japanese MPN patients, including 52 with PV, 131 with ET, and 18 with PMF, as well as 366 control individuals for TERT rs2736100 and JAK2 rs10974944, a tagging SNP of the 46/1 haplotype. Furthermore, correlations between the JAK2 V617F allele burden at diagnosis and TERT rs2736100 or JAK2 rs10974944 were evaluated using a digital PCR assay for accurate quantitation. The JAK2 46/1 haplotype, but not the TERT rs2736100 SNP, was correlated to the JAK2 V617F mutant allele burden in JAK2 V617F-positive MPN patients. In conclusion, we demonstrated that both TERT rs2736100_C and JAK2 46/1 haplotype are predisposing factors for MPNs in Japanese patients. While TERT rs2736100_C tended to have a more general, non-specific effect on all MPNs, the JAK2 46/1 haplotype was essentially predisposed to the JAK2 V617F-positive MPNs.

Systemic AL amyloidosis with disseminated intravascular coagulation associated with hyperfibrinolysis.

Many coagulation abnormalities are known to coexist in patients with AL amyloidosis; however, disseminated intravascular coagulation (DIC) is rarely observed. We describe the case of a 61-year-old woman who presented with systemic purpura, macroscopic hematuria, and hepatosplenomegaly as the initial manifestations of systemic AL amyloidosis. A coagulation study revealed severe DIC associated with fibrinolysis. The patient was treated for DIC with gabexate mesilate (GM); however, her bleeding symptoms and thrombocytopenia continued to worsen. The treatment was changed from GM to nafamostat mesilate (NM); DIC improved gradually, and the platelet count normalized in 1 week. After the tapering and cessation of NM therapy, deterioration of DIC did not occur. She underwent autologous peripheral blood stem cell transplantation twice following high-dose melphalan therapy, and received maintenance therapy with thalidomide. Hepatosplenomegaly progression appears to have been halted, and DIC has not recurred. This is the first reported case of AL amyloidosis showing severe DIC with excessive fibrinolysis. The clinical observation that NM was considerably more effective than GM in our patient suggests that NM may be more suitable for the treatment of DIC with a hyperfibrinolytic condition in AL amyloidosis patients.