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.

Outcomes of transplant-eligible patients with myelodysplastic syndrome with excess blasts registered in an observational study: The JALSG-CS11-MDS-SCT.

Allogeneic hematopoietic stem cell transplantation (allo-SCT) is the sole curative therapy for myelodysplastic syndrome (MDS). However, whether bridging therapy (BRT) including azacitidine (AZA) and combination chemotherapy (CCT) prior to allo-SCT should be performed is unclear. We analyzed BRT and the outcomes of patients with myelodysplastic syndrome with excess blasts (MDS-EB) who were ≤ 70 years old at the time of registration for a prospective observational study to clarify the optimal allo-SCT strategy for high-risk MDS. A total of 371 patients were included in this study. Among 188 patients (50.7%) who were considered for allo-SCT, 141 underwent allo-SCT. Among the patients who underwent allo-SCT, 64 received AZA, 29 received CCT, and 26 underwent allo-SCT without BRT as the initial treatment. Multivariate analysis identified BRT as an independent factor influencing overall survival (AZA vs. without BRT, hazard ratio [HR] 3.33, P = 0.005; CCT vs. without BRT, HR 3.82, P = 0.003). In multivariate analysis, BRT was independently associated with progression-free survival (AZA vs. without BRT: HR, 2.23; P = 0.041; CCT vs. without BRT: HR, 2.94; P = 0.010). Transplant-eligible patients with MDS-EB should undergo allo-SCT when clinically acceptable, and upfront allo-SCT without BRT may be superior to AZA or CCT.

Essential Roles of the Transcription Factor NR4A1 in Regulatory T Cell Differentiation under the Influence of Immunosuppressants.

Calcineurin inhibitors (CNIs), used as immunosuppressants, have revolutionized transplantation medicine with their strong suppressive activity on alloreactive T lymphocytes; however, they may also cause various adverse effects, including an increased risk for infection and nephrotoxicity. Regulatory T (Treg) cells can complement the deleterious side effects of CNIs with their effective Ag-specific suppressive activities. However, several studies have shown that CNIs suppress Treg cell differentiation. Therefore, an understanding of the mechanisms by which CNIs suppress Treg cell differentiation, as well as an approach for promoting the differentiation of Treg cells in the presence of CNIs, has significant clinical value. In this article, we report that the nuclear orphan receptor Nr4a1 plays a pivotal role in Treg cell differentiation in the presence of CNIs. Unlike that of its family members, Nr4a2 and Nr4a3, the expression of Nr4a1 was not suppressed by CNI treatment, thereby mediating Treg cell differentiation in the presence of CNIs. In a mouse allogeneic graft-versus-host disease model, Nr4a1 mediated tolerance by promoting Treg cell differentiation in mice administered cyclosporine A, prolonging the survival of recipients. Furthermore, activation of Nr4a1 via its agonist partially restored Treg cell differentiation, which was suppressed by cyclosporine A treatment. Finally, we found that the rs2701129 single-nucleotide polymorphism, which was shown to downregulate NR4A1 expression, showed a trend toward a higher incidence of chronic graft-versus-host disease in patients undergoing hematopoietic stem cell transplantation. Therefore, our study will be of clinical significance because we demonstrated the role of Nr4a1 in Treg cell differentiation in the presence of CNIs.

Immunoreactivity to WT1 peptide vaccine is associated with prognosis in elderly patients with acute myeloid leukemia: follow-up study of randomized phase II trial of OCV-501, an HLA class II-binding WT1 polypeptide.

We previously conducted a randomized phase II trial of OCV-501, a WT1 peptide presented by helper T cells, in elderly AML (acute myeloid leukemia) patients in first remission, indicating no difference in 2-year disease-free survival (DSF) between the OCV-501 and placebo groups. Here, we analyzed 5-year outcome and biomarkers. Five-year DFS was 36.0% in the OCV-501 group (N = 52) and 33.7% in the placebo group (N = 53), with no significant difference (p = 0.74). The peripheral WT1 mRNA levels were marginally suppressed in the OCV-501 group compared with the placebo group. Enhanced anti-OCV-501 IgG response by the 25th week was an independent favorable prognostic factor. Anti-OCV-501 IFNγ responses were less frequent than the IgG reactions. These findings suggest that host immunoreactivity has a significant impact on the prognosis of AML and that further improvement of the WT1 peptide vaccine is needed.

Venetoclax plus low-dose cytarabine in patients with newly diagnosed acute myeloid leukemia ineligible for intensive chemotherapy: an expanded access study in Japan.

BACKGROUND: In a Phase 3 international clinical trial (VIALE-C), venetoclax plus low-dose cytarabine improved the response rate and overall survival versus placebo plus low-dose cytarabine in patients with newly diagnosed acute myeloid leukemia who were ineligible for intensive chemotherapy. After the enrollment period of VIALE-C ended, we conducted an expanded access study to provide preapproval access to venetoclax in combination with low-dose cytarabine in Japan. METHODS: Previously, untreated patients with acute myeloid leukemia who were ineligible for intensive chemotherapy were enrolled according to the VIALE-C criteria. Patients received venetoclax (600 mg, Days 1-28, 4-day ramp-up in Cycle 1) in 28-day cycles and low-dose cytarabine (20 mg/m2, Days 1-10). All patients took tumor lysis syndrome prophylactic agents and hydration. Safety endpoints were assessed. RESULTS: Fourteen patients were enrolled in this study. The median age was 77.5 years (range = 61-84), with 78.6% over 75 years old. The most common grade ≥ 3 treatment-emergent adverse event was neutropenia (57.1%). Febrile neutropenia was the most frequent serious adverse event (21.4%). One patient developed treatment-related acute kidney injury, leading to discontinuation of treatment. Two patients died because of cardiac failure and disease progression that were judged not related to study treatment. No patients developed tumor lysis syndrome. CONCLUSIONS: The safety outcomes were similar to those in VIALE-C without new safety signals and were well managed with standard medical care. In clinical practice, more patients with severe background disease are expected, in comparison with in VIALE-C, suggesting that it is important to carefully manage and prevent adverse events.

Clinical significance of late CMV disease in adult patients who underwent allogeneic stem cell transplant.

INTRODUCTION: Late cytomegalovirus (CMV) disease, which was defined as CMV disease occurring >100 days post-transplant, remains an important complication among allogeneic stem cell transplant recipients, even now that the prophylactic strategy using ganciclovir preemptive therapy has been established. Due to the recent expansion of donor sources and conditioning regimens, it is therefore appropriate to reevaluate the incidence, risk factors, and clinical impacts of late CMV disease. METHODS: This study included the 1295 adult patients, who underwent transplant for the first time from 2008 to 2015, without underlying disease relapse or CMV disease within 100 days post-transplant. There were no restrictions on underlying diseases or transplant procedures. RESULTS: During the median follow-up period of 48.4 months, 21 patients developed late CMV disease and the 5-year cumulative incidence of late CMV disease was 1.6%. By multivariate analysis, haploidentical related donor, adult T-cell leukemia lymphoma, and preemptive therapy before 100 days post-transplant were extracted as independent risk factors. Late CMV disease negatively affected transplant outcomes, and was identified as an independent risk factor for the non-relapse mortality rate (hazard ratio 3.83, p < 0.001) and overall survival rate (hazard ratio 4.01, p < 0.001). Although 17 of 21 patients with late CMV disease died, the main causes of death were not related to CMV, except in three patients with CMV pneumonia. CONCLUSIONS: Although the incidence of late CMV disease is low in transplant recipients, this complication negatively affects clinical courses. Therefore, transplant recipients with these risk factors should be more carefully managed.

Overcoming minimal residual disease using intensified conditioning with medium-dose etoposide, cyclophosphamide and total body irradiation in allogeneic stem cell transplantation for Philadelphia chromosome-positive acute lymphoblastic leukemia in adults.

BACKGROUND AIMS: An intensified conditioning regimen incorporating medium-dose etoposide (VP16) is an option for patients with acute lymphoblastic leukemia (ALL). However, the prognostic impacts of the addition of VP16 to cyclophosphamide (CY) and total body irradiation (TBI) in patients with Philadelphia chromosome-positive (Ph+) ALL with regard to minimal residual disease (MRD) status have not been elucidated. METHODS: The authors retrospectively compared the outcomes of patients with Ph+ ALL who underwent allogeneic transplantation following VP16/CY/TBI (n = 101) and CY/TBI (n = 563). RESULTS: At 4 years, the VP16/CY/TBI group exhibited significantly better disease-free survival (DFS) (72.6% versus 61.7%, P = 0.027) and relapse rate (11.5% versus 21.1%, P = 0.020) and similar non-relapse mortality (16.0% versus 17.2%, P = 0.70). In subgroup analyses, the beneficial effects of the addition of VP16 on DFS were more evident in patients with positive MRD status (71.2% versus 48.4% at 4 years, P = 0.022) than those with negative MRD status (72.8% versus 66.7% at 4 years, P = 0.24). Although MRD positivity was significantly associated with worse DFS in patients who received CY/TBI (48.4% versus 66.7%, P < 0.001), this was not the case in those who received VP16/CY/TBI (71.2% versus 72.8%, P = 0.86). CONCLUSIONS: This study demonstrated the benefits of the addition of VP16 in Ph+ ALL patients, especially those with positive MRD status. VP16/CY/TBI could be a potential strategy to overcome the survival risk of MRD positivity.

Advantages of peripheral blood stem cells from unrelated donors versus bone marrow transplants in outcomes of adult acute myeloid leukemia patients.

BACKGROUND AIMS: In allogeneic stem cell transplantation, unrelated donors are chosen in cases where appropriate related donors are not available. Peripheral blood stem cells (PBSCs) are more often selected as a graft source than bone marrow (BM). However, the prognostic benefits of PBSCs versus BM transplants from unrelated donors have not been carefully examined in patients with acute myeloid leukemia (AML). This study compared outcomes of adult AML patients who underwent unrelated PBSC and BM transplantation, evaluating post-transplant complications, including engraftment, graft-versus-host disease (GVHD) and infections, and determined subgroups of patients who are most likely to benefit from unrelated PBSCs compared with BM transplants. METHODS: The authors analyzed 2962 adult AML patients who underwent unrelated PBSC or BM transplants between 2011 and 2018 (221 PBSC and 2741 BM) using the Japanese nationwide registry database, in which graft source selection is not skewed toward PBSCs. RESULTS: In 49.7% of patients, disease status at transplantation was first complete remission (CR1). In 57.1% of cases, HLA-matched donors were selected. Myeloablative conditioning was performed in 75.1% of cases, and anti-thymocyte globulin (ATG) was added to conditioning in 10.5%. Multivariate analyses showed a trend toward favorable non-relapse mortality (NRM) in PBSC recipients compared with BM recipients (hazard ratio [HR], 0.731, P = 0.096), whereas overall survival (OS) (HR, 0.959, P = 0.230) and disease-free survival (DFS) (HR, 0.868, P = 0.221) were comparable between PBSC and BM recipients. Although the rate of chronic GVHD (cGVHD) was significantly higher in PBSC patients (HR, 1.367, P = 0.016), NRM was not increased, mainly as a result of significantly reduced risk of bacterial infections (HR, 0.618, P = 0.010), reflecting more prompt engraftments in PBSC recipients. Subgroup analyses revealed that PBSC transplantation was advantageous in patients transplanted at CR1 and in those without ATG use. PBSC recipients experienced significantly better OS and/or DFS compared with BM recipients in this patient group. CONCLUSIONS: The authors' results confirmed the overall safety of unrelated PBSC transplantation for adult AML patients and suggested an advantage of PBSCs, especially for those in CR1. Further optimization of the prophylactic strategy for cGVHD is required to improve the overall outcome in transplantation from unrelated PBSC donors.

Adult patients with Ph+ ALL benefit from conditioning regimen of medium-dose VP16 plus CY/TBI.

The medium-dose etoposide (VP16) added on cyclophosphamide (CY)/total body irradiation (TBI) is one of the intensified myeloablative conditioning regimens used in allogenic hematopoietic stem cell transplantation (allo-HSCT) for acute lymphoblastic leukemia (ALL). However, the patient subgroups who can actually benefit from VP16/CY/TBI compared to CY/TBI have not been precisely defined. Therefore, we conducted a multi-center retrospective study using the Japanese nationwide registry database to elucidate the efficacy of VP16/CY/TBI on post-transplant prognosis. Biological and clinical distinct subtypes (i.e., Philadelphia chromosome-positive (Ph+) and -negative (Ph-) ALL) were evaluated separately, which included 820 Ph+ and 1463 patients with Ph- ALL, respectively. Compared with the CY/TBI group, the VP16/CY/TBI group showed superior progression-free survival (PFS) in patients with Ph+ ALL (65% vs. 57% at 3 years after HSCT; adjusted hazard ratio (HR), 0.73; 95% confidence interval (CI), 0.55-0.98; p = 0.03), along with significantly reduced incidence of relapse (adjusted HR, 0.58; 95% CI, 0.37-0.90; p = 0.02) without the increase of non-relapse mortality (NRM). By contrast, in patients with Ph- ALL, VP16/CY/TBI did not improve PFS nor incidence of relapse; addition of VP16 reduced relapse (HR, 0.65; p = 0.06) in patients with Ph- ALL transplanted at CR1, while improved PFS was not observed (HR, 0.90; p = 0.52) due to increased NRM. This study demonstrated that VP16/CY/TBI is a more effective and well-tolerated regimen in comparison with CY/TBI in patients with myeloablative allo-HSCT for adult Ph+ ALL. Our findings can provide a novel algorithm for conditioning regimen selection in patients with adult ALL.

Safety and Efficacy of Blinatumomab in Japanese Adult and Pediatric Patients with Relapsed/Refractory B-Cell Precursor Acute Lymphoblastic Leukemia: Final Results from an Expansion Cohort.

INTRODUCTION: The safety and efficacy of blinatumomab, a CD19/CD3 bispecific T-cell engager (BiTE®) molecule, was evaluated in an expansion cohort of the phase 1b/2 study (NCT02412306) in Japanese adult (n = 14) and pediatric (n = 17) patients with relapsed/refractory Philadelphia-negative B-cell precursor (BCP) acute lymphoblastic leukemia (ALL). MATERIALS AND METHODS: Globally recommended blinatumomab doses were administered to adult (9-28 µg/day) and pediatric (5-15 µg/m2/day) patients. Primary endpoint was the incidence of treatment-emergent adverse events (TEAEs) and treatment-related AEs. RESULTS: All adult and pediatric patients experienced ≥1 TEAE. Grade ≥3 TEAEs were observed in 11 (79%) adult and 15 (88%) pediatric patients. Blinatumomab was discontinued in 1 (6%) pediatric patient due to treatment-related grade 4 cytokine release syndrome. Fatal AEs such as disease progression and multiple-organ dysfunction syndrome, which were not treatment-related, were reported in 2 (12%) pediatric patients. Eleven (79%) adults achieved complete remission (CR)/CR with partial hematological recovery (CRh) within the first two blinatumomab cycles. Nine of 10 adult patients with CR/CRh and evaluable minimal residual disease (MRD) achieved MRD response. CR/CRh was achieved by 5 (29%) pediatric patients, of which two had MRD response. CONCLUSION: In conclusion, blinatumomab was safe and efficacious in Japanese patients with relapsed/refractory BCP ALL.

Venetoclax plus low-dose cytarabine in Japanese patients with untreated acute myeloid leukaemia ineligible for intensive chemotherapy.

BACKGROUND: In a multinational phase 3 trial (VIALE-C), venetoclax plus low-dose cytarabine prolonged overall survival vs placebo plus low-dose cytarabine in patients with newly diagnosed acute myeloid leukaemia ineligible for intensive chemotherapy, although it was not statistically significant. Herein, we assess the benefit of venetoclax plus low-dose cytarabine in the Japanese subgroup of VIALE-C patients (n = 27). METHODS: VIALE-C, a randomized (2:1), double-blind study (NCT03069352), enrolled untreated patients (≥18 years) with acute myeloid leukaemia. Patients received venetoclax (600 mg days 1-28, 4-day ramp-up in cycle 1) or placebo in 28-day cycles with low-dose cytarabine (20 mg/m2 days 1-10). The primary endpoint was median overall survival. RESULTS: In the Japanese subgroup, at a 6-month follow-up from the primary analysis, median overall survival for venetoclax (n = 18) and placebo (n = 9), plus low-dose cytarabine, was 4.7 and 8.1 months, respectively (hazard ratio, 0.928, 95% confidence intervals : 0.399, 2.156). The rate of complete remission plus complete remission with incomplete blood count recovery was higher with venetoclax plus low-dose cytarabine (44.4%) vs placebo plus low-dose cytarabine (11.1%). All patients experienced at least 1 adverse event. The most common grade ≥3 adverse events with venetoclax or placebo, plus low-dose cytarabine, were febrile neutropenia (50.0% vs 44.4%, respectively) and thrombocytopenia (27.8% vs 44.4%, respectively). Serious adverse events were reported in 50.0 and 33.3% of patients in the venetoclax and placebo, plus low-dose cytarabine arms, respectively; pneumonia was the most common (22.2% each). CONCLUSIONS: Limited survival benefit in the Japanese subgroup can be attributed to small patient numbers and to baseline imbalances observed between treatment arms, with more patients in the venetoclax plus low-dose cytarabine arm presenting poor prognostic factors. Venetoclax plus low-dose cytarabine was well tolerated in Japanese patients with acute myeloid leukaemia ineligible for intensive chemotherapy.

Study on the lower limit of indoor humidity subject experiments on psychological responses.

As a basis for determining the lower limit of acceptable humidity in an indoor environment, experiments were conducted for 25 subjects to assess the maximum expected sensations of dryness, discomfort based on humidity, and intolerance based on humidity, under conditions of 26°C and 10% RH. As results, distinct negative evaluations (dry, uncomfortable, or intolerable) were not obtained as the majority response; however, a small number of subjects declared distinct negative responses. In addition to the whole-body evaluation, the sensations for individual body parts were collected and found to be more intense for the eyes, nose, throat, and lips than for the other body parts. Significant differences between the genders were not found. For 8 of the subjects, similar experiments under a condition of 30% RH were conducted, and the difference between two humidity conditions was clearer for discomfort and intolerance than for dryness. The results suggest that the evaluation of the specific individuals who respond intensely, the consideration of intense responses for a specific part of the body, and the careful selection of an evaluation word for a psychological response might be effective to link this study to the determination of the lower limit of indoor humidity.

Updated Comparison of 7/8 HLA Allele-Matched Unrelated Bone Marrow Transplantation and Single-Unit Umbilical Cord Blood Transplantation as Alternative Donors in Adults with Acute Leukemia.

The outcomes of 7/8 allele-matched unrelated bone marrow transplantation (7/8 UBMT) and umbilical cord blood transplantation (UCBT) have been improving. We retrospectively analyzed adults with acute leukemia who underwent their first 7/8 UBMT or UCBT in Japan. Between January 2008 and December 2017, a total of 4150 patients were recorded, including 488 who underwent 7/8 UBMT and 3662 who underwent UCBT. Only 32 patients with 7/8 UBMT had graft-versus-host-disease (GVHD) high-risk HLA mismatched pairs. Overall survival at 3 years was 54% for 7/8 the UBMT group and 46% for the UCBT group, a nonsignificant difference in multivariate analysis (hazard ratio [HR], 1.01; 95% confidence interval [CI], .88 to 1.17; P = .89). The 7/8 UBMT and UCBT groups showed a similar nonrelapse mortality rate (HR, 1.16; 95% CI, .96 to 1.45; P = .16) and relapse rate (HR, .85; 95% CI, .71 to 1.02; P = .08). However, the UCBT group had a lower risk of grade II-IV acute GVHD (HR, .76; 95% CI, .65 to .88; P < .001) and chronic GVHD (HR, .77; 95% CI, .66- .91; P = .002) compared with the 7/8 UBMT group. In stratified analyses combining disease risk with conditioning intensity, 7/8 UBMT showed superior overall survival to UCBT in standard risk and myeloablative conditioning (HR, .72; 95% CI, .56 to .93; P = .014). Both 7/8 UBMT and UCBT are appropriate alternative donor procedures. The stem cell source can be selected on the basis of disease risk, patient tolerability, or concerns regarding GVHD.

Impact of HLA Allele Mismatch at HLA-A, -B, -C, and -DRB1 in Single Cord Blood Transplantation.

The impact of allele-level HLA mismatch on outcomes of cord blood transplantation has not been well established. We retrospectively analyzed the effects of HLA allele matching at HLA-A, -B, -C, and -DRB1 in cord blood transplantation for acute myeloid leukemia, acute lymphoblastic leukemia, and myelodysplastic syndrome. In multivariate analysis, overall survival (OS) significantly deteriorated in the 4-allele or higher mismatch in pediatric cases (hazard ratio, 1.8 for 4/8 match [reference, 6/8 match] and 2.85 for 3-1/8 match) and the 5-allele or higher mismatch in adult cases (hazard ratio, 1.23 for 3-0/8 match). Incidence of grade Ⅲ to Ⅳ acute graft-versus-host disease was low in the 8/8 match and 1-allele mismatch in pediatric cases (hazard ratio, 0.19 for 8/8 match and 0.41 for 7/8 match) and the 8/8 match in adult cases (hazard ratio, 0.41 for 8/8 match). On the other hand, a higher incidence of relapse was noted in the 8/8 match in adults (hazard ratio, 1.53). The incidence of neutrophil and platelet engraftment decreased in the 3-allele or higher mismatch in adults. In subgroup analysis of graft-versus-host disease prophylaxis in adult cases, a deteriorating effect on OS of HLA 5-allele or higher mismatch was more significant in cases with calcineurin inhibitor with methotrexate than with mycophenolate mofetil. These results suggest that allele-level HLA mismatch affects the outcomes of cord blood transplantation. Information on HLA allele matching at HLA-A, -B, -C, and -DRB1 may be useful for cord blood unit selection.

Effect of allogeneic HCT from unrelated donors in AML patients with intermediate- or poor-risk cytogenetics: a retrospective study from the Japanese Society for HCT.

This study aimed to analyze the factors associated with outcomes of bone marrow transplantation (UR-BMT) or cord blood stem cell transplantation from unrelated donors (UR-CBT). We assessed the time from diagnosis to transplantation among acute myeloid leukemia (AML) patients with intermediate- or poor-risk cytogenetics to identify the potential clinical efficacy of transplantation. We retrospectively analyzed 5331 patients who received UR-BMT or UR-CBT between 2008 and 2017. Patients were divided into four groups according to time from diagnosis to transplantation: (1) UR-BMT and > 5 months (n = 2353), (2) UR-BMT and ≤ 5 months (n = 379), (3) UR-CBT and > 5 months (n = 1494), and (4) UR-CBT and ≤ 5 months (n = 1106). There was no difference in overall survival (OS) for transplantation at ≤5 months and > 5 months in patients with first complete remission for both UR-BMT and UR-CBT, but OS in patients with primary induction failure (PIF) and transplantation at ≤ 5 months was significantly higher in the UR-CBT group compared with that at >5 months (P < 0.001). Multivariate Cox regression analysis also showed that transplantation at >5 months in patients with PIF was an independent predictor of poorer OS. Therefore, UR-CBT at ≤ 5 months after diagnosis is an alternative option for AML patients with PIF.

The impacts of BCR-ABL1 mutations in patients with Philadelphia chromosome-positive acute lymphoblastic leukemia who underwent allogeneic hematopoietic cell transplantation.

The prognostic impacts of BCR-ABL1 fusion gene mutations in Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph + ALL) remain unknown. Using data from a nationwide Japanese registry, we have evaluated the prognostic impact of BCR-ABL1 mutations prior to the first allogeneic hematopoietic cell transplantation (HCT). The cohort included 289 patients with a median of 48 years of age (range: 16-70). Point mutations were detected in 110 patients. Of these, 90 (82%) harbored T315I mutations, while 20 had other mutations. With a median follow-up period of 29 months (range: 1-125), outcomes after 2 years were worse with mutations than without (overall survival [OS]: 34% vs 68%, p < 0.001; relapse rate [RR]: 48% vs 18%, p < 0.001), particularly with the presence of the T315I mutation (OS: 29% vs 68%, p < 0.001; RR: 54% vs 18%, p < 0.001). OS was significantly worse in the T315I group even among the cohort with hematological (p < 0.001) or molecular complete remission (p = 0.025) as compared to the no mutation group. Multivariate analysis determined the prognostic impact of the T315I mutation (OS: hazard ratio [HR] = 2.19, 95% confidence interval [CI]: 1.5-3.3, p < 0.001; RR: HR = 2.51, 95% CI: 1.5-4.2, p < 0.001). This study is the first to report on the prognostic significance of BCR-ABL1 mutations in Ph + ALL.

Clonal evolution detected with conventional cytogenetic analysis is a potent prognostic factor in adult patients with relapsed AML.

We retrospectively investigated 144 patients with relapsed acute myeloid leukemia (AML) to clarify predisposing factors and the prognostic impact of acquisition of additional cytogenetic abnormalities (ACA) at the first relapse. Additional cytogenetic abnormalities are recognized as clonal evolution at the cytogenetic level. Fifty-nine patients (41%) acquired ACA at the first relapse. The incidences of ACA acquisition varied depending on cytogenetic abnormalities at initial diagnosis. Multivariate analysis identified t(8;21), complex karyotype, and a duration of fewer than 12 months of complete remission as independent predisposing factors for ACA acquisition. Notably, patients with ACA acquisition showed a significantly lower second complete remission rate compared with those without ACA acquisition (20.0% vs 72.5%, respectively, P < .001). Furthermore, the 3-year overall survival rates after the first relapse were significantly different between patients with and without ACA acquisition (8.5% vs 36.8%, respectively, P < .001). This prognostic significance was confirmed with multivariate analysis. The hazard ratio of ACA acquisition was similar or higher than reported prognostic factors for relapsed AML patients. These findings suggested that clonal evolution detected with conventional cytogenetic analysis at the first relapse induces severe chemo-refractory characteristics in AML cells and should be considered as a potent prognostic factor when evaluating accurate prognosis in relapsed AML patients.

Philadelphia chromosome-positive mixed phenotype acute leukemia in the imatinib era.

Although the introduction of imatinib dramatically improved the outcomes for patients with Philadelphia chromosome-positive B-cell precursor acute lymphoblastic leukemia (Ph + BCP-ALL), the survival benefit of imatinib has not been assessed in the context of Ph + mixed phenotype acute leukemia (Ph + MPAL). To clarify this important issue, we studied 42 Ph+ acute leukemia (Ph + AL) patients who received intensive chemotherapy and concurrent administration of imatinib. Of the 42 Ph + AL patients, 13 (31%) patients were categorized as Ph + MPAL (positive for both myeloid and B-cell lineage), 27 (64%) were categorized as Ph + BCP-ALL, and two (5%) were categorized as Ph + acute myeloid leukemia. The complete remission rates after the initial induction therapy were not significantly different when comparing Ph + MPAL and Ph + BCP-ALL patients (100% vs. 85%, respectively, P = 0.14). Likewise, there were no significant differences in the 5-yr overall survival (OS) or disease-free survival (DFS) rates when comparing the MPAL and BCP-ALL groups (OS: 55% vs. 53%, respectively, P = 0.87, DFS: 46% vs. 42%, respectively, P = 0.94). These findings suggest that concurrent imatinib administration with chemotherapy improved the outcomes of Ph + MPAL patients to the level seen in Ph+BCP-ALL patients and should, therefore, be considered as the standard therapy for these patients.

Updated comparable efficacy of cord blood transplantation for chronic myelomonocytic leukaemia: a nationwide study.

Chronic myelomonocytic leukaemia (CMML) is a haematological malignancy with a poor prognosis. Allogeneic haematopoietic stem cell transplantation remains the only curative approach. Without human leucocyte antigen-matched related sibling donors, the optimal alternative donor has yet to be established. Although unrelated bone marrow transplantation (UBMT) has been extensively studied, cord blood transplantation (CBT) for CMML remains largely unexplored. This nationwide retrospective study compared the outcomes of UBMT and single-unit umbilical CBT in patients with CMML. This study included 118 patients who underwent their first allo-HSCT during 2013-2021. Of these, 50 received BMT (UBMT group), while 68 underwent CBT (CBT group). The primary endpoint was the 3-year overall survival (OS). There were comparable 3-year OS rates between the UBMT (51.0%, 95% confidence interval [CI]: 34.1-65.5%) and CBT (46.2%, 95% CI: 33.2-58.1%; P = 0.60) groups. In the inverse probability of treatment weighting analysis, CBT did not show significantly improved outcomes compared with UBMT regarding the 3-year OS rate (hazard ratio 0.97 [95% CI: 0.57-1.66], P = 0.91). Thus, CBT may serve as an alternative to UBMT for patients with CMML. Further research is necessary to optimise transplantation strategies and enhance outcomes in patients with CMML undergoing CBT.

Comparative Analysis of Allogeneic Bone Marrow Transplantation Outcomes Between Japanese and Non-Japanese Populations.

BACKGROUND: As the Japanese population may have less genetic diversity than other ethnic groups, treatment outcomes may be affected when allogeneic hematopoietic cell transplantation is performed in other races. However, evidence explaining the effect of racial differences is limited. METHODS: We used the Japanese National Database to examine the outcomes of first allogeneic bone marrow transplantations (BMTs) performed between Japanese and non-Japanese patients from 1996 to 2021. We performed propensity score matching using sex, age group, underlying disease group, HLA mismatch, conditioning regimen intensity, and BMT implementation age to select Japanese-to-Japanese BMT patients as the controls. RESULTS: The numbers of non-Japanese-to-Japanese and Japanese-to-non-Japanese BMT cases included in the analysis were 48 and 75, respectively, and the following outcomes were compared: overall survival, non-relapse mortality, acute graft-vs-host disease (GVHD) ≥ grade II, chronic GVHD, and engraftment of neutrophils and platelets. Most parameters did not differ when comparing BMTs according to ethnicity; only platelet engraftment was delayed in Japanese-to-non-Japanese BMT but not in non-Japanese-to-Japanese BMT. CONCLUSIONS: The results of this study suggested that BMT performed in Japanese and non-Japanese patients has little effect on treatment outcomes. The results of this study may be useful for donor selection in Japan, where internationalization has progressed in recent years.