[Intestinal pneumatosis developed during the treatment of severe gastrointestinal graft-versus-host disease after cord blood transplantation].

A 62-year-old female developed stage4 gastrointestinal graft-versus-host disease (GVHD) on day 109 following an allogeneic cord blood transplant for relapsed refractory angioimmunoblastic T-cell lymphoma. GVHD went into remission 4 weeks after receiving the steroid (mPSL 1 mg/kg), but abdominal bloating started to emerge at the same time. A diagnosis of intestinal pneumatosis was made on day 158 after a CT scan revealed submucosal and serosal pneumatosis in the entire colon, and intestinal pneumatosis was identified as the cause. Fasting and reducing steroid use have helped. the abdominal symptoms, and the pneumatosis disappeared on day 175. No more flare-ups occurred, and the steroid was successfully stopped. After allogeneic transplantation, intestinal pneumatosis is a rather uncommon complications. Its pathogenesis is thought to be influenced by GVHD or steroids. Treatments for the disease may be incompatible with one another, and the response in individual cases needs to be studied in detail.

[Complete remission after standard induction therapy in a patient with acute myeloid leukemia associated with double-minute chromosomes].

Acute myeloid leukemia (AML) associated with double-minute chromosomes (dmin) is a rare condition and has a poor prognosis. A 68-year-old man with leukocytosis and thrombocytopenia was admitted to our hospital. Bone marrow aspiration showed that 79.5% of myeloblasts were positive for myeloperoxidase. The patient was diagnosed with acute myeloid leukemia (French-American-British classification: M2, World Health Organization classification: AML, not otherwise specified, AML with maturation). Chromosomal analysis revealed the presence of dmin: 45, X, -Y, 5-33 dmin. Fluorescence in situ hybridization revealed multiple MYC signals, and spectral karyotyping showed that dmin was derived from chromosome 8. These findings indicated resistance to chemotherapy alone. After the standard induction therapy with daunorubicin and cytarabine, the number of myeloblasts in the bone marrow decreased, and the amplified MYC signals disappeared. Then, the patient achieved complete remission. Reportedly, most patients with AML correlated with dmin have a complex karyotype, except for this case. Owing to the absence of a complex karyotype, the patient had good sensitivity to chemotherapy. Further studies with a larger population of patients with AML associated with dmin, but without complex karyotypes, should be conducted to accurately predict prognosis in such cases.

Permanent Impairment-Free, Relapse-Free Survival: A Novel Composite Endpoint to Evaluate Long-Term Success in Allogeneic Transplantation.

Permanent impairment (PI) of vital organs is one of the transplantation-related health problems affecting the quality of life and morbidity even in patients who do not develop graft-versus-host disease (GVHD) after allogeneic hematopoietic stem cell transplantation (allo-HCT), but no data are available on PI of multiple organs. This retrospective study aimed to estimate a novel composite endpoint of PI-free, relapse-free survival (PIRFS) in 164 allo-HCT recipients. We defined PI as >26% to 30% impairment of the whole person in 6 vital organs using the whole person impairment rating. Conventional GVHD-free/relapse-free survival (GRFS) and PIRFS at 5 years were 33.8% (95% confidence interval [CI], 26.5% to 41.3%) and 40.6% (95% CI, 32.6% to 48.4%), respectively. In the whole cohort, PIRFS was higher than GRFS at any time after allo-HCT. However, PIRFS was lower than GRFS after day 397 post-transplantation in patients who underwent umbilical cord blood transplantation (UCBT). In UCBT recipients, 5-year GRFS and PIRFS were 47.6% (95% CI, 34.3% to 59.7%) and 39.2% (95% CI, 26.6% to 51.5%), respectively. The cumulative incidence of PI after 5 years was 20.9% (95% CI, 13.7% to 29.0%) in patients surviving for ≥6 months without relapse. The multivariate analysis revealed that high disease risk (hazard ratio [HR], 1.91; 95% CI, 1.26 to 2.88; P < .01) and Karnofsky Performance Status score ≤90% at transplantation (HR, 1.73; 95% CI, 1.14 to 2.63; P = .01) were correlated with the lower PIRFS, whereas UCBT (HR, 2.35; 95% CI, 1.11 to 4.99; P = .03), grade III-IV acute GVHD by day 180 (HR, 3.59; 95% CI, 1.04 to 12.4; P = .04), and thrombotic microangiopathy by day 180 (HR, 2.74; 95% CI, 1.10 to 6.87; P = .03) were significantly correlated with a higher incidence of PI. More than 20% of long-term survivors had PI. Our data suggest that PIRFS is a useful endpoint for assessing long-term transplantation success from a different perspective than has been established previously.

Impact of a Nutritional Risk Index on Clinical Outcomes after Allogeneic Hematopoietic Cell Transplantation.

Nutritional status is an important component of cancer care, and malnutrition itself can cause death in 10% to 20% of cancer patients. A nutritional risk index (NRI) is a useful tool for nutritional assessment of cancer patients. This study aimed to evaluate the impact of pretransplant NRI values on outcomes of allogeneic hematopoietic cell transplantation (allo-HSCT). One hundred sixty patients who underwent allo-HSCT between January 2008 and July 2017 at Konan Kosei Hospital were included in this single-center, retrospective analysis. NRI was calculated at the beginning of the conditioning regimen. The patients were divided into high NRI (NRI ≥ 97.5) and low NRI (NRI < 97.5) groups, and overall survival (OS), nonrelapse mortality (NRM), and cumulative incidences of acute and chronic graft-versus-host disease (GVHD) were evaluated. Two-year OS rates were 76% (95% confidence interval [CI], 63% to 83%) and 50.4% (95% CI, 38% to 62%) in the high NRI and low NRI groups, respectively (P < .001). One-year cumulative incidences of NRM were 7.9% (95% CI, 3.5% to 15%) and 23% (95% CI, 14% to 33%; P = .014) and 2-year cumulative relapse rates were 17% (95% CI, 10% to 26%) and 32% (95% CI, 21% to 43%; P = .10) in the high NRI and low NRI groups, respectively. The multivariate analysis indicated low NRI was a significant risk factor for OS and NRM. Conversely, high NRI was associated with increased incidences of grades II to IV acute GVHD and chronic GVHD. Additionally, the subgroup analysis according to stem cell source revealed a significant benefit of higher NRI on survival only in umbilical cord blood recipients. Overall, these results suggest that pretransplant NRI might predict OS and NRM after allo-HSCT.

Promising Outcome of Umbilical Cord Blood Transplantation in Patients with Multiple Comorbidities.

The hematopoietic cell transplantation-specific comorbidity index (HCT-CI) has been recently proposed to predict the probability of nonrelapse mortality (NRM) and overall survival (OS) in allogeneic hematopoietic stem cell transplantation (HSCT). However, the usefulness of the HCT-CI in single-unit umbilical cord blood transplantation (UCBT) remains unclear. We investigated the impact of the HCT-CI on the clinical outcomes of allogeneic HSCT in a single-center retrospective study including 53 recipients of UCBT (UCBT group) and 90 recipients of other HSCT (non-UCBT group). In the non-UCBT group 2-year OS rates for HCT-CI score < 3 and ≥3 were 67% (n = 74; 95% confidence interval [CI], 54% to 78%) and 26% (n = 16; 95% CI, 7% to 51%), respectively (P = .001). In the UCBT group these rates were 66% (n = 39; 95% CI, 48% to 79%) and 69% (n = 14; 95% CI, 36% to 87%), respectively (P = .73). In the non-UCBT group 1-year NRM rates for HCT-CI score < 3 and ≥3 were 14% (95% CI, 6.4% to 22%) and 37% (95% CI, 14% to 61%), respectively (P = .02). In the UCBT group these rates were 6.1% (95% CI, 3.4% to 24%) and 7.7% (95% CI, .4% to 29%), respectively (P = .78). Using multivariate analysis we showed that HCT-CI score ≥ 3 was significantly associated with lower OS (hazard ratio, 3.06; 95% CI, 1.47 to 6.38; P = .003) and higher NRM (hazard ratio, 2.87; 95% CI, 1.18 to 6.96; P = .02) for the non-UCBT group. UCBT showed good OS with low incidence of NRM, even in patients with high HCT-CI scores. Altogether, we propose single-unit UCB to be a promising stem cell source for improving survival in patients with multiple comorbidities.

A Novel Diagnostic and Prognostic Biomarker Panel for Endothelial Cell Damage-Related Complications in Allogeneic Transplantation.

Noninfectious transplantation-related complications (TRCs), such as graft-versus-host disease or TRC with endothelial cell damage (TRC-EC), remain as the major obstacle for successful allogeneic hematopoietic cell transplantation (allo-HCT). However, the diagnosis and prognosis for the emergence of these complications are difficult to define during the early post allo-HCT period. Here, we tried to generate a novel diagnostic system for TRC-EC by analyzing 188 adult patients who received allo-HCT. Our study found that the peripheral blood levels of angiopoietin 2 (ANG2), C-reactive protein (CRP), D-dimer, and thrombomodulin (TM) at the onset of TRCs were significantly associated with the development of TRC-EC. We next developed a composite biomarker panel incorporating the risk values of ANG2, CRP, D-dimer, and TM at the onset of TRCs, which classified these patients into 3 risk groups: low, intermediate, and high risk. As a result, the panel was useful not only for the diagnosis of TRC-EC with high specificity and sensitivity, but also for the prediction of the patients' long-term outcome. The 5-year overall survival (OS) rates of patients in the low-, intermediate-, and high-risk groups since the occurrence from TRCs were 76.2%, 54.9%, and 26.9%, respectively, and the high-risk score was significantly associated with both poor OS (hazard ratio [HR], 5.60; 95% confidence interval [CI], 2.81 to 11.20; P < .01) and frequent nonrelapse mortality (HR, 19.75; 95% CI, 5.59 to 69.77; P < .01). Thus, the composite panel proposed in this study provides a powerful tool for the diagnosis of TRC-EC and for the prediction of survival for patients with TRC-EC after allo-HCT.

Predictive value of circulating angiopoietin-2 for endothelial damage-related complications in allogeneic hematopoietic stem cell transplantation.

Endothelial cell damage has been reported to be associated with noninfectious transplant-related complications after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Among these, noninfectious transplant-related complications with endothelial cell damage (TRC-EC) include sinusoidal occlusive syndrome, transplant-associated microangiopathy, intestinal transplant-associated microangiopathy, capillary leak syndrome, idiopathic pneumonia syndrome, and diffuse alveolar hemorrhage. Because angiopoietin-2 (ANG2) plays an essential role in the endothelial cell damage of various inflammatory disorders, we hypothesized that ANG2 may also play a critical role in TRC-EC. We retrospectively estimated the incidence of TRC-EC and evaluated the association with ANG2 level at transplant. We studied 153 consecutive adult patients who underwent allo-HSCT at our institution between 2000 and 2012. Median patient age was 49 years (range, 16 to 68 years). With a median follow-up of 55 months, 3-year overall survival for all patients was 55%. The incidence of TRC-EC at day 100 was significantly higher in the high-ANG2 group (≥2000 pg/mL; n = 36) than in the low-ANG2 group (<2000 pg/mL; n = 117) (70% [95% confidence interval {CI}, 55% to 84%] versus 16% [95% CI, 11% to 24%]; P < .001). Multivariate analysis revealed that high ANG2 level at transplant was independently associated with higher risk of TRC-EC (hazard ratio, 6.01; 95% CI, 3.16 to 11.43; P < .001) and shorter overall survival (hazard ratio, 2.23; 95% CI, 1.66 to 4.48; P = .002). These results suggest that ANG2 level at transplant may be a useful marker for predicting the risk of TRC-EC after allo-HSCT. Prospective studies are warranted to validate our results.

Successful treatment of acyclovir-resistant herpes simplex virus infection with amenamevir in a patient who received umbilical cord blood transplantation for T-cell prolymphocytic leukemia.

A 34-year-old woman received umbilical cord blood transplantation for refractory T-cell prolymphocytic leukemia after salvage therapy with alemtuzumab. She developed right angular cheilitis on the 46th day after transplantation, which worsened after receiving systemic steroid therapy for extensive chronic graft versus host disease. The treatment dosage of acyclovir (ACV), ganciclovir, and vidarabine ointment was not effective due to ACV-resistant mutations of the herpes simplex virus type 1 (HSV-1) in the thymidine kinase domain. Foscarnet is expected to be effective against ACV-resistant HSV-1 infection. However, it could not be used because the patient developed renal dysfunction. Several viral thymidine kinase mutations related to ACV resistance were found in the patient's sample. Nevertheless, amenamevir, a helicase-primase complex inhibitor, was effective in our patient who was significantly immunocompromised after allogeneic hematopoietic stem cell transplantation (allo-HSCT). ACV-resistant HSV infection after allo-HSCT is an rare but important complication in the era of low-dose long-term ACV prophylaxis. To date, there is no established treatment against ACV-resistant HSV infection. This case report showed that amenamevir could be a promising treatment option for ACV-resistant HSV infection in patients with renal failure after allo-HSCT.

Effect of Conditioning Regimens and Graft-versus-Host Disease Prophylaxis on the Outcomes of Umbilical Cord Blood Transplantation Performed with Cyclophosphamide/Total Body Irradiation-Based Regimens.

Umbilical cord blood (UCB) is a valuable alternative donor source for allogeneic hematopoietic stem cell transplantation. Various conditioning regimens and graft-versus-host disease (GVHD) prophylaxis regimens aimed at improving the outcomes of umbilical cord blood transplantation (UCBT) have been explored; however, the differences in their effects remain unclear. This study was conducted to elucidate the differences in the effects of conditioning and GVHD prophylaxis regimens on UCBT outcomes by disease type in a nationwide, retrospective study. We retrospectively analyzed the effects of conditioning and GVHD prophylaxis regimens on the outcomes of UCBT performed with cyclophosphamide (Cy)/total body irradiation (TBI)-based regimens in patients with acute myeloid leukemia (AML; n = 1126), acute lymphoblastic leukemia (ALL; n = 620), myelodysplastic syndrome (MDS; n = 170), and lymphoma (n = 128). Multivariate analysis for overall survival (OS) demonstrated the benefit of adding high-dose cytarabine to the Cy/TBI regimen for the AML group (relative risk [RR], .76; P = .003) and lymphoma group (RR, .54; P = .02), but not for the ALL and MDS groups. In the ALL group, adding etoposide to the Cy/TBI regimen was associated with a lower OS (RR, 1.45; P = .03). For GVHD prophylaxis, a tacrolimus/methotrexate regimen was associated with a lower OS compared with a cyclosporine/methotrexate regimen in the AML group (RR, 1.26; P = .01); this difference was not observed in the other groups. These differences in OS according to the conditioning and GVHD prophylaxis regimen were attributable mainly to differences in relapse risk. Our data show that the effects of conditioning regimens and GVHD prophylaxis on UCBT outcomes differed according to disease type. UCBT outcomes could be improved by selecting optimal conditioning regimens and GVHD prophylaxis for each disease type.

Clonal hematopoiesis of a novel dic(18;20) clone following allogeneic hematopoietic stem cell transplantation.

A 55-year-old man in first complete remission of acute myeloid leukemia with a normal karyotype underwent allogeneic hematopoietic stem cell transplantation from a human-leukocyte-antigen-matched sibling. Bone marrow examination on day 28 confirmed complete remission, but G-banding analysis revealed a novel chromosomal abnormality, including dic(18;20)(p11.2;q11.2). The patient developed moderate chronic graft-versus-host disease on day 174, and the abnormal clones identified by dic(18;20) significantly increased after that point. Chimerism testing repeatedly confirmed complete donor type. Although next-generation sequencing showed no clonal hematopoiesis-related gene mutations, copy number analysis of the donor and the recipient revealed copy number deletion of 18p, 18q, and 20q. The patient has maintained remission for more than 2 years to date without developing a hematologic neoplasm or cytopenia. The distinctive clonal hematopoiesis with a dicentric chromosome seemed to have undergone the breakage-fusion-bridge cycle, which could cause the complex events of deletion, amplification, and inversion. These copy number alterations might have increased the number of clones with growth advantage, and the highly inflammatory environment in the recipient due to graft-versus-host disease might have contributed to the clonal selection.

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.

Long-Term Outcome of Eltrombopag With First-Line Immunosuppressive Therapy for Newly Diagnosed Severe Aplastic Anemia.

Background: To investigate whether the addition of eltrombopag (EPAG) to rabbit anti-thymocyte globulin (ATG)-based immunosuppressive therapy (IST) for newly diagnosed severe aplastic anemia (SAA) improves outcomes and affects the cumulative incidence of clonal evolution (CE), we conducted a multicenter retrospective analysis. Methods: Data were collected from 101 patients, aged 15 - 65 years, undergoing initial IST. Results: No significant imbalance in age, sex, or severity was observed between the EPAG (n = 20) and non-EPAG (n = 81) groups. The median duration of EPAG administration in EPAG group was 16.1 months (range: 0.6 - 41.1 months). Six months after the initiation of IST, the complete response (CR) rate significantly improved in the EPAG group (P < 0.01). The cumulative incidence of allogeneic stem cell transplantation (allo-SCT) at 2 years and the 2-year overall survival (OS) were not significantly different between the two groups (allo-SCT, P = 0.31; OS, P = 0.64). Grade 3-4 adverse events in the EPAG group and the cumulative incidence of CE (P = 0.96) showed no increase. Conclusion: In summary, IST showed significantly better initial efficacy in the EPAG group. Although the addition of EPAG did not reduce the need for allo-SCT, no increase was observed in the incidence of CE with long-term EPAG use.

Three cases of suspected pleuroparenchymal fibroelastosis after allogeneic hematopoietic cell transplantation.

This article reports the clinical course and imaging findings of three cases of suspected pleuroparenchymal fibroelastosis (PPFE) after allogeneic hematopoietic cell transplantation (HCT). All patients complained of dyspnea more than 5 years after HCT, had progressive restrictive deficits on respiratory function tests, and presented with pneumothorax, pleural thickening, or exacerbation of consolidation in the upper lobe of the lung. Though lung biopsy was not done in all three cases, the clinical findings and results of spirometry were compatible with those of PPFE. PPFE has been sporadically reported as a pulmonary complication of allogeneic HCT; however, clinical diagnostic criteria other than histological diagnosis and treatment methods have not yet been established. The accumulation of more cases is necessary to improve the prognosis of PPFE complications.

Development of TCR-T cell therapy targeting mismatched HLA-DPB1 for relapsed leukemia after allogeneic transplantation.

Relapsed leukemia after allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains a significant challenge, with the re-emergence of the primary disease being the most frequent cause of death. Human leukocyte antigen (HLA)-DPB1 mismatch occurs in approximately 70% of unrelated allo-HSCT cases, and targeting mismatched HLA-DPB1 is considered reasonable for treating relapsed leukemia following allo-HSCT if performed under proper conditions. In this study, we established several clones restricted to HLA-DPB1*02:01, -DPB1*04:02, and -DPB1*09:01 from three patients who underwent HLA-DPB1 mismatched allo-HSCT using donor-derived alloreactive T cells primed to mismatched HLA-DPB1 in the recipient's body after transplantation. A detailed analysis of the DPB1*09:01-restricted clone 2A9 showed reactivity against various leukemia cell lines and primary myeloid leukemia blasts, even with low HLA-DP expression. T cell receptor (TCR)-T cells derived from clone 2A9 retained the ability to trigger HLA-DPB1*09:01-restricted recognition and lysis of various leukemia cell lines in vitro. Our study demonstrated that the induction of mismatched HLA-DPB1 specific T cell clones from physiologically primed post-allo-HSCT alloreactive CD4+ T cells and the redirection of T cells with cloned TCR cDNA by gene transfer are feasible as techniques for future adoptive immunotherapy.

Antibody response after third dose of COVID-19 mRNA vaccination in allogeneic hematopoietic stem cell transplant recipients is comparable to that in healthy counterparts.

To determine the efficacy of SARS-CoV-2 mRNA vaccination for allogeneic hematopoietic stem cell transplantation (allo-HSCT) recipients, we measured antibody titer serially in 92 allo-HSCT patients. Among the evaluable 87 patients, median age at vaccination was 53 years (range, 18-75). The average time between allo-HSCT and vaccination was 3.3 years (range, 0.5-15.7). One month after the second dose, 70 patients (80.5%) had a positive response, whereas 17 patients (19.5%) had a negative response (< 20 U/mL). Only patients older than 44 years had a negative response. Low IgM level was the only significant predictor of vaccine failure in elderly patients. When antibody response before and after the third vaccination was examined in 47 patients, antibodies increased significantly from a median of 18.3 U/mL to 312.6 U/mL (P < 0.01). The median antibody titer after the third vaccination of healthy individuals (n = 203) was 426.4 U/mL, which was comparable to that of patients (P = 0.2). The antibody titer after the third mRNA vaccination increased even in patients whose first two mRNA vaccinations failed. These findings suggest that allo-HSCT recipients should receive the mRNA vaccine regularly.

T cell receptor-engineered T cells derived from target human leukocyte antigen-DPB1-specific T cell can be a potential tool for therapy against leukemia relapse following allogeneic hematopoietic cell transplantation.

Human leukocyte antigen (HLA)-DPB1 antigens are mismatched in approximately 70% of allogeneic hematopoietic stem cell transplantations (allo-HSCT) from HLA 10/10 matched unrelated donors. HLA-DP-mismatched transplantation was shown to be associated with an increase in acute graft-versus-host disease (GVHD) and a decreased risk of leukemia relapse due to the graft-versus-leukemia (GVL) effect. Immunotherapy targeting mismatched HLA-DP is considered reasonable to treat leukemia following allo-HCT if performed under non-inflammatory conditions. Therefore, we isolated CD4+ T cell clones that recognize mismatched HLA-DPB1 from healthy volunteer donors and generated T cell receptor (TCR)-gene-modified T cells for future clinical applications. Detailed analysis of TCR-T cells expressing TCR from candidate clone #17 demonstrated specificity to myeloid and monocytic leukemia cell lines that even expressed low levels of targeted HLA-DP. However, they did not react to non-hematopoietic cell lines with a substantial level of targeted HLA-DP expression, suggesting that the TCR recognized antigenic peptide is only present in some hematopoietic cells. This study demonstrated that induction of T cells specific for HLA-DP, consisting of hematopoietic cell lineage-derived peptide and redirection of T cells with cloned TCR cDNA by gene transfer, is feasible when using careful specificity analysis.

Allogeneic Hematopoietic Cell Transplantation for Patients with Relapsed Acute Promyelocytic Leukemia.

Although autologous hematopoietic cell transplantation (HCT) is an established therapy for patients with relapsed acute promyelocytic leukemia (APL) after returning to complete remission (CR), the role of allogeneic HCT remains unclear for treating relapsed APL. This study aimed to investigate allogeneic HCT outcomes in patients with relapsed APL, focusing particularly on those who underwent transplantation in non-CR and those who had relapsed after prior autologous HCT. We retrospectively analyzed Japanese nationwide transplantation registry data of patients with relapsed APL age ≥16 years who underwent allogeneic HCT between 2006 and 2020. A total of 195 patients were eligible for this analysis, including 69 who underwent transplantation in non-CR and 55 who relapsed after prior autologous HCT. The median duration of follow-up for survivors was 5.4 years. Multivariate analysis revealed that both non-CR at transplantation (hazard ratio [HR], 1.74; 95% confidence interval [CI], 1.12 to 2.71; P = .014) and prior autologous HCT (HR, 2.10; 95% CI, 1.28 to 3.44; P = .013) were associated with higher risks of overall mortality. The 5-year overall survival (OS) rates for patients who underwent transplantation in CR and non-CR were 58% and 39%, respectively (P = .085), if they did not have a history of prior autologous HCT. In the patients who had relapsed after prior autologous HCT, the 5-year OS rate was 47% for those who underwent allogeneic HCT in CR and 6% for those who did so in non-CR (P = .001). Allogeneic HCT still provides an opportunity for long-term survival for certain patients with relapsed APL for whom autologous HCT is unlikely to be effective. The dismal outcome of those with prior autologous HCT who underwent allogeneic HCT in non-CR poses a significant therapeutic challenge.

KW-2449, a novel multikinase inhibitor, suppresses the growth of leukemia cells with FLT3 mutations or T315I-mutated BCR/ABL translocation.

KW-2449, a multikinase inhibitor of FLT3, ABL, ABL-T315I, and Aurora kinase, is under investigation to treat leukemia patients. In this study, we examined its possible modes of action for antileukemic effects on FLT3-activated, FLT3 wild-type, or imatinib-resistant leukemia cells. KW-2449 showed the potent growth inhibitory effects on leukemia cells with FLT3 mutations by inhibition of the FLT3 kinase, resulting in the down-regulation of phosphorylated-FLT3/STAT5, G(1) arrest, and apoptosis. Oral administration of KW-2449 showed dose-dependent and significant tumor growth inhibition in FLT3-mutated xenograft model with minimum bone marrow suppression. In FLT3 wild-type human leukemia, it induced the reduction of phosphorylated histone H3, G(2)/M arrest, and apoptosis. In imatinib-resistant leukemia, KW-2449 contributed to release of the resistance by the simultaneous down-regulation of BCR/ABL and Aurora kinases. Furthermore, the antiproliferative activity of KW-2449 was confirmed in primary samples from AML and imatinib-resistant patients. The inhibitory activity of KW-2449 is not affected by the presence of human plasma protein, such as alpha1-acid glycoprotein. These results indicate KW-2449 has potent growth inhibitory activity against various types of leukemia by several mechanisms of action. Our studies indicate KW-2449 has significant activity and warrants clinical study in leukemia patients with FLT3 mutations as well as imatinib-resistant mutations.

Intrapatient variability in concentration/dose ratio of tacrolimus predicts transplant-associated thrombotic microangiopathy.

Tacrolimus (TAC) is essential for prophylaxis of acute graft-versus-host disease (aGVHD) after allogeneic hematopoietic cell transplantation (allo-HSCT). We have sometimes observed large fluctuations in TAC concentration. However, links between the variability in the concentration or the concentration/dose (C/D) ratio of TAC and clinical complications remain ambiguous. To clarify relationships between various parameters of TAC and early complications such as pre-engraftment immune reactions/engraftment syndrome, aGVHD, and transplant-associated thrombotic microangiopathy (TA-TMA), a total of 146 patients who underwent allo-HSCT were included. Intrapatient variabilities in the concentration and C/D ratio of TAC were estimated by intrapatient mean absolute deviation (iMAD). The mean concentration and C/D ratio of TAC were not significantly different between with and without complications. A strong association was observed between greater iMAD for TAC C/D ratio from days 15 to 21 and the development of TA-TMA. iMAD values for TAC C/D ratio of 11.4 or greater was a risk factor for TA-TMA and the cumulative incidence of nonrelapse mortality (NRM) was significantly higher in patients with iMAD values for TAC C/D ratio of 11.4 or greater. Intrapatient variability in the C/D ratio of TAC was associated with the incidence of TA-TMA and NRM and might be useful for predicting TA-TMA.

Severe tumor lysis syndrome during the induction therapy for the treatment of blastic plasmacytoid dendritic cell neoplasm arising from myelodysplastic/myeloproliferative neoplasms.

BPDCN shows clinically heterogeneous characteristics. And as other hematological malignancies, symptoms of BPDCN suggesting a high tumor burden, such as high white blood cell count or splenomegaly, should be carefully considered to prevent TLS.