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Activating FLT3 and RAS mutations commonly occur in leukemia with KMT2A -gene rearrangements ( KMT2A -r). However, how these mutations cooperate with the KMT2A -r to remodel the epigenetic landscape is unknown. Using a retroviral acute myeloid leukemia (AML) mouse model driven by KMT2A::MLLT3 , we show that FLT3 ITD , FLT3 N676K , and NRAS G12D remodeled the chromatin accessibility landscape and associated transcriptional networks. Although the activating mutations shared a common core of chromatin changes, each mutation exhibits unique profiles with most opened peaks associating with enhancers in intronic or intergenic regions. Specifically, FLT3 N676K and NRAS G12D rewired similar chromatin and transcriptional networks, distinct from those mediated by FLT3 ITD . Motif analysis uncovered a role for the AP-1 family of transcription factors in KMT2A::MLLT3 leukemia with FLT3 N676K and NRAS G12D , whereas Runx1 and Stat5a/Stat5b were active in the presence of FLT3 ITD . Furthermore, transcriptional programs linked to immune cell regulation were activated in KMT2A -r AML expressing NRAS G12D or FLT3 N676K , and the expression of NKG2D-ligands on KMT2A -r cells rendered them sensitive to CAR T cell-mediated killing. Human KMT2A -r AML cells could be pharmacologically sensitized to NKG2D-CAR T cells by treatment with the histone deacetylase inhibitor LBH589 (panobinostat) which caused upregulation of NKG2D-ligand levels. Co-treatment with LBH589 and NKG2D-CAR T cells enabled robust AML cell killing, and the strongest effect was observed for cells expressing NRAS G12D . Finally, the results were validated and extended to acute leukemia in infancy. Combined, activating mutations induced mutation-specific changes in the epigenetic landscape, leading to changes in transcriptional programs orchestrated by specific transcription factor networks., Competing Interests: The authors declare no conflict of interest., (© 2024 The Author(s). HemaSphere published by John Wiley & Sons Ltd on behalf of European Hematology Association.)

Hyperleukocytosis in pediatric acute myeloid leukemia (AML) is associated with severe complications and an inferior outcome. We report results on patients with hyperleukocytosis included in the NOPHO-DBH AML 2012 study. We recommended immediate initiation of full-dose chemotherapy (etoposide monotherapy for 5 days as part of the first course), avoiding leukapheresis and prephase chemotherapy. Of 714 patients included in the NOPHO-DBH AML 2012 study, 122 (17.1%) had hyperleukocytosis, and 111 were treated according to the recommendations with etoposide upfront without preceding leukapheresis or prephase chemotherapy. The first dose was applied the same day as the AML diagnosis or the day after in 94%. Etoposide was administered via peripheral veins in 37% of patients without major complications. After initiation of etoposide the white blood cell counts on days 2-5 were 69%, 36%, 17% and 8%, respectively, of the pre-treatment level. On day 3, 81% of patients had a white blood cell count <100 x109/L. Five-year event-free and overall survival rates for all patients with hyperleukocytosis were 52.9% (95% confidence interval [95% CI]: 44.4-63.0) and 74.1% (95% CI: 66.4-82.6), compared to 64.9% (95% CI: 60.9-69.1) and 78.9% (95% CI: 75.4-82.4) for patients without hyperleukocytosis (P<0.001 for event-free survival, P=0.1 overall survival). Six-week early mortality was 4.1% for all patients with hyperleukocytosis (2.7% for the 111 patients treated with etoposide upfront). We conclude that management of hyperleukocytosis in pediatric AML with immediate etoposide monotherapy without leukapheresis or prephase chemotherapy is feasible, safe and effective. The reduction in white blood cell count during the first days is comparable to the reported results of leukapheresis, and outcomes seem at least equivalent to therapies including leukapheresis. Based on our results, we advocate abandoning leukapheresis for hyperleukocytosis in pediatric AML. Instead, it is crucial to start induction chemotherapy as early as possible.

Purpose: Measurable residual disease (MRD) by using flow cytometry after induction therapy is strongly prognostic in pediatric AML, and hematopoietic stem-cell transplant (hSCT) may counteract a poor response. We designed a phase III study with intensified response-guided induction and MRD-based risk stratification and treated poor induction response with hSCT. The efficacy of liposomal daunorubicin (DNX) in induction was compared with mitoxantrone., Methods: The study planned to randomly assign 300 patients, but the production of DNX ceased in 2017. One hundred ninety-four patients were randomly assigned to mitoxantrone or experimental DNX in induction 1. Ninety-three non-randomly assigned patients served as an observation cohort. Primary end point was fraction of patients with MRD <0.1% on day 22 after induction 1. Patients with MRD ≥15% after induction 1 or ≥0.1% after induction 2 or FLT3 -ITD with NPM1 wildtype were stratified to high-risk therapy, including hSCT., Results: Outcome for all 287 children was good with 5-year event-free survival (EFS 5y ) 66.7% (CI, 61.4 to 72.4) and 5-year overall survival (OS 5y ) 79.6% (CI, 75.0 to 84.4). Overall, 75% were stratified to standard-risk and 19% to high-risk. There was no difference in the proportion of patients with MRD <0.1% on day 22 after induction 1 (34% mitoxantrone, etoposide, araC [MEC], 30% DNX, P = .65), but the proportion increased to 61% for MEC versus 47% for DNX ( P = .061) at the last evaluation before induction 2. EFS 5y was significantly lower, 56.6% (CI, 46.7 to 66.5) versus 71.9% (CI, 63.0 to 80.9), and cumulative incidence of relapse (CIR) was higher, 35.1% (CI, 25.7 to 44.7) versus 18.8% (CI, 11.6 to 27.2) for DNX. The inferior outcome for DNX was only in standard-risk patients with EFS 5y 55.3% (CI, 45.1 to 67.7) versus 79.9% (CI, 71.1 to 89.9), CIR 39.5% (CI, 28.4 to 50.3) versus 18.7% (CI, 10.5 to 28.7), and OS 5y 76.2% (CI, 67.2 to 86.4) versus 88.6% (CI, 81.4 to 96.3). As-treated analyses, including the observation cohort, supported these results. For all high-risk patients, 85% received hSCT, and EFS 5y was 77.7 (CI, 67.3 to 89.7) and OS 5y was 83.0 (CI, 73.5 to 93.8)., Conclusion: The intensification of induction therapy with risk stratification on the basis of response to induction and hSCT for high-risk patients led to improved outcomes. Mitoxantrone had a superior anti-leukemic effect than liposomal daunorubicin.

Diamond-Blackfan anaemia (DBA), first described over 80 years ago, is a congenital disorder of erythropoiesis with a predilection for birth defects and cancer. Despite scientific advances, this chronic, debilitating, and life-limiting disorder continues to cause a substantial physical, psychological, and financial toll on patients and their families. The highly complex medical needs of affected patients require specialised expertise and multidisciplinary care. However, gaps remain in effectively bridging scientific discoveries to clinical practice and disseminating the latest knowledge and best practices to providers. Following the publication of the first international consensus in 2008, advances in our understanding of the genetics, natural history, and clinical management of DBA have strongly supported the need for new consensus recommendations. In 2014 in Freiburg, Germany, a panel of 53 experts including clinicians, diagnosticians, and researchers from 27 countries convened. With support from patient advocates, the panel met repeatedly over subsequent years, engaging in ongoing discussions. These meetings led to the development of new consensus recommendations in 2024, replacing the previous guidelines. To account for the diverse phenotypes including presentation without anaemia, the panel agreed to adopt the term DBA syndrome. We propose new simplified diagnostic criteria, describe the genetics of DBA syndrome and its phenocopies, and introduce major changes in therapeutic standards. These changes include lowering the prednisone maintenance dose to maximum 0·3 mg/kg per day, raising the pre-transfusion haemoglobin to 9-10 g/dL independent of age, recommending early aggressive chelation, broadening indications for haematopoietic stem-cell transplantation, and recommending systematic clinical surveillance including early colorectal cancer screening. In summary, the current practice guidelines standardise the diagnostics, treatment, and long-term surveillance of patients with DBA syndrome of all ages worldwide., Competing Interests: Declaration of interests AK declares honoraria from chiesi and Novartis and a research grant from Novaris. AK is on the advisory board of Chiesi and Novartis. FML declares honoraria from Chiesi and is on the advisory board of Chiesi. LK is on the advisory board of Agios, Amgen, Bayer, and Novartis. All other authors declare no competing interests., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

A significant proportion of events in paediatric acute myeloid leukaemia (AML) are caused by resistant disease (RD). We investigated clinical and biological characteristics in 66 patients with RD from 1013 children with AML registered and treated according to the NOPHO-AML 93, NOPHO-AML 2004, DB AML-01 and NOPHO-DBH AML 2012 protocols. Risk factors for RD were age10 years or older and a white-blood-cell count (WBC) of 100 × 10 9 /L or more at diagnosis. The five-year overall survival (OS) was 38% (95% confidence interval [CI]: 28%-52%). Of the 63 children that received salvage therapy with chemotherapy, 59% (N = 37) achieved complete remission (CR) with OS 57% (95% CI: 42%-75%) compared to 12% (95% CI: 4%-35%) for children that did not achieve CR. Giving more than two salvage chemotherapy courses did not increase CR rates. OS for all 43 patients receiving allogeneic haematopoietic stem cell transplantation (HSCT) was 49% (95% CI: 36%-66%). Those achieving CR and proceeding to HSCT had an OS of 56% (95% CI: 41%-77%, N = 30). This study showed that almost 40% of children with primary resistant AML can be cured with salvage therapy followed by HSCT. Children that did not achieve CR after two salvage courses with chemotherapy did not benefit from additional chemotherapy., (© 2023 The Authors. British Journal of Haematology published by British Society for Haematology and John Wiley & Sons Ltd.)

The clinical presentation of chronic myeloid leukemia (CML) at diagnosis differs in children compared to adults. At younger age, anemia appears to be frequent at diagnosis, but its prevalence and its impact on prognosis are not well known. In the International Registry of Childhood CML, we selected children and adolescents in chronic phase at diagnosis of CML and treated upfront with imatinib. We examined their hemoglobin level at diagnosis according to the WHO grades to assess the prevalence of anemia and its impact on response to tyrosine kinase inhibitors (TKIs). Data on 430 patients were included. Anemia at diagnosis was observed in 350 patients (81%), with a mean hemoglobin level of 96.4 g/l (SD 23.6). Among them, 182 patients (52%) presented with moderate anemia and 110 (31%) with severe anemia while 58 (17%) had mild anemia. Compared with mild and no anemia, moderate and severe forms were significantly associated with younger age at diagnosis, asthenia, splenomegaly, and increased leukocyte and basophil counts. Delays in achieving major and deep molecular responses were significantly increased for patients with moderate and severe anemia, and also failure of imatinib treatment was more frequent in these two sub-cohorts. However, hemoglobin level was not significantly associated with survival. Anemia at diagnosis of pediatric CML was frequent and may be considered as a prognostic factor., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The relative lack of marine venom pharmaceuticals can be anecdotally attributed to difficulties in working with venomous marine animals, including how to maintain venom bioactivity during extraction and purification. The primary aim of this systematic literature review was to examine the key factors for consideration when extracting and purifying jellyfish venom toxins to maximise their effectiveness in bioassays towards the characterisation of a single toxin.An up-to-date database of 119 peer-reviewed research articles was established for all purified and semi-purified venoms across all jellyfish, including their level of purification, LD50, and the types of experimental toxicity bioassay used (e.g., whole animal and cell lines). We report that, of the toxins successfully purified across all jellyfish, the class Cubozoa (i.e., Chironex fleckeri and Carybdea rastoni ) was most highly represented, followed by Scyphozoa and Hydrozoa. We outline the best practices for maintaining jellyfish venom bioactivity, including strict thermal management, using the "autolysis" extraction method and two-step liquid chromatography purification involving size exclusion chromatography. To date, the box jellyfish C. fleckeri has been the most effective jellyfish venom model with the most referenced extraction methods and the most isolated toxins, including CfTX-A/B. In summary, this review can be used as a resource for the efficient extraction, purification, and identification of jellyfish venom toxins.

Introduction: Analysis of measurable residual disease (MRD) is increasingly being implemented in the clinical care of children and adults with acute myeloid leukaemia (AML). However, MRD methodologies differ and discordances in results lead to difficulties in interpretation and clinical decision-making. The aim of this study was to compare results from reverse transcription quantitative polymerase chain reaction (RT-qPCR) and multiparameter flow cytometry (MFC) in childhood AML and describe the kinetics of residual leukaemic burden during induction treatment., Methods: In 15 children who were treated in the NOPHO-AML 2004 trial and had fusion transcripts quantified by RT-qPCR, we compared MFC with RT-qPCR for analysis of MRD during (day 15) and after induction therapy. Eight children had RUNX1::RUNX1T1, one CBFB::MYH11 and six KMT2A::MLLT3., Results: When ≥0.1% was used as cut-off for positivity, 10 of 22 samples were discordant. The majority (9/10) were MRD positive with RT-qPCR but MRD negative with MFC, and several such cases showed the presence of mature myeloid cells. Fusion transcript expression was verified in mature cells as well as in CD34 expressing cells sorted from diagnostic samples., Conclusions: Measurement with RT-qPCR suggests slower response kinetics than indicated from MFC, presumably due to the presence of mature cells expressing fusion transcript. The prognostic impact of early measurements with RT-qPCR remains to be determined., (© 2022 The Authors. International Journal of Laboratory Hematology published by John Wiley & Sons Ltd.)

Introduction: Pediatric acute myeloid leukemia (AML) is the second most common type of pediatric leukemia. Patients with AML are at high risk for several complications such as infections, typhlitis, and acute and long-term cardiotoxicity. Despite this knowledge, there are no definite supportive care guidelines as to what the best approach is to manage or prevent these complications., Area Covered: The NOPHO-DB-SHIP (Nordic-Dutch-Belgian-Spain-Hong-Kong-Israel-Portugal) consortium, in preparation for a new trial in pediatric AML patients, had dedicated meetings for supportive care. In this review, the authors discuss the available data and outline recommendations for the management of children and adolescents with AML with an emphasis on hyperleukocytosis, tumor lysis syndrome, coagulation abnormalities and bleeding, infection, typhlitis, malnutrition, cardiotoxicity, and fertility preservation., Expert Opinion: Improved supportive care has significantly contributed to increased cure rates. Recommendations on supportive care are an essential part of treatment for this highly susceptible population and will further improve their outcome.

Infant acute lymphoblastic leukemia (ALL) with KMT2A -gene rearrangements ( KMT2A -r) have few mutations and a poor prognosis. To uncover mutations that are below the detection of standard next-generation sequencing (NGS), a combination of targeted duplex sequencing and NGS was applied on 20 infants and 7 children with KMT2A -r ALL, 5 longitudinal and 6 paired relapse samples. Of identified nonsynonymous mutations, 87 had been previously implicated in cancer and targeted genes recurrently altered in KMT2A -r leukemia and included mutations in KRAS , NRAS , FLT3 , TP53 , PIK3CA , PAX5 , PIK3R1 , and PTPN11 , with infants having fewer such mutations. Of identified cancer-associated mutations, 62% were below the resolution of standard NGS. Only 33 of 87 mutations exceeded 2% of cellular prevalence and most-targeted PI3K/RAS genes (31/33) and typically KRAS/NRAS . Five patients only had low-frequency PI3K/RAS mutations without a higher-frequency signaling mutation. Further, drug-resistant clones with FLT3 D835H or NRAS G13D/G12S mutations that comprised only 0.06% to 0.34% of diagnostic cells, expanded at relapse. Finally, in longitudinal samples, the relapse clone persisted as a minor subclone from diagnosis and through treatment before expanding during the last month of disease. Together, we demonstrate that infant and childhood KMT2A -r ALL harbor low-frequency cancer-associated mutations, implying a vast subclonal genetic landscape., (Copyright © 2022 the Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the European Hematology Association.)

Acute myeloid leukemia (AML) accounts for 15% to 20% of childhood leukemias. Because of high-intensive therapy, up to 5% of patients suffer from treatment-related mortality (TRM). Abdominal complications are frequent, however, literature on this subject is sparse. We aimed to characterize severe abdominal pain (AP) and hyperbilirubinemia experienced by pediatric AML patients treated according to the Nordic Society of Pediatric Hematology and Oncology (NOPHO)-AML 2004 protocol (n=313). Patients were censored at hematopoietic stem cell transplantation and relapse. Toxicity information was collected prospectively. Additional information was requested retrospectively from the treating centers. Sixteen episodes of hyperbilirubinemia and 107 episodes of AP were reported. The treating centers deemed infection (30%) and typhlitis (18%) as the most frequent causes of AP. Six patients developed appendicitis (2%). Patients experiencing concurrent AP and sepsis had a high risk of TRM (36%, n=4). Eighty percent of episodes with hyperbilirubinemia fulfilled the European Society for Bone and Marrow Transplantation criteria for sinusoidal obstruction syndrome. In conclusion, abdominal complications were frequent with infection considered the predominate cause. Most patients with hyperbilirubinemia fulfilled the criteria for sinusoidal obstruction syndrome. AML treatment might be associated with appendicitis. Patients suffering from concurrent AP and sepsis had a high risk of TRM indicating that high awareness of abdominal complications is essential to reduce mortality, especially during sepsis., Competing Interests: The authors declare no conflict of interest., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Background: The outcome of infants with KMT2A-germline acute lymphoblastic leukaemia (ALL) is superior to that of infants with KMT2A-rearranged ALL but has been inferior to non-infant ALL patients. Here, we describe the outcome and prognostic factors for 167 infants with KMT2A-germline ALL enrolled in the Interfant-06 study., Methods: Univariate analysis on prognostic factors (age, white blood cell count at diagnosis, prednisolone response and CD10 expression) was performed on KMT2A-germline infants in complete remission at the end of induction (EOI; n = 163). Bone marrow minimal residual disease (MRD) was measured in 73 patients by real-time quantitative polymerase chain reaction at various time points (EOI, n = 68; end of consolidation, n = 56; and before OCTADAD, n = 57). MRD results were classified as negative, intermediate (<5∗10 -4 ), and high (≥5∗10 -4 )., Results: The 6-year event-free and overall survival was 73.9% (standard error [SE] = 3.6) and 87.2% (SE = 2.7). Relapses occurred early, within 36 months from diagnosis in 28 of 31 (90%) infants. Treatment-related mortality was 3.6%. Age <6 months was a favourable prognostic factor with a 6-year disease-free survival (DFS) of 91% (SE = 9.0) compared with 71.7% (SE = 4.2) in infants >6 months of age (P = 0.04). Patients with high EOI MRD ≥5 × 10 -4 had a worse outcome (6-year DFS 61.4% [SE = 12.4], n = 16), compared with patients with undetectable EOI MRD (6-year DFS 87.9% [SE = 6.6], n = 28) or intermediate EOI MRD <5 × 10 -4 (6-year DFS 76.4% [SE = 11.3], n = 24; P = 0.02)., Conclusion: We conclude that young age at diagnosis and low EOI MRD seem favourable prognostic factors in infants with KMT2A-germline ALL and should be considered for risk stratification in future clinical trials., Competing Interests: Conflict of interest statement The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Overexpressed genes may be useful for monitoring of measurable residual disease (MRD) in patients with childhood acute myeloid leukemia (AML) without a leukemia-specific target. The normal expression of five leukemia-associated genes (SPAG6, ST18, MSLN, PRAME, XAGE1A) was defined in children without hematologic disease (n = 53) and children with suspected infection (n = 90). Gene expression at AML diagnosis (n=50) and during follow-up (n = 21) was compared with child-specific reference values. At diagnosis, 34/50 children (68%) had high expression of at least one of the five genes, and so did 16/31 children (52%) without a leukemia-specific target. Gene expression was quantified in 110 peripheral blood (PB) samples (median, five samples/patient; range, 1 to 10) during follow-up in 21 patients with high expression at diagnosis. All nine patients with PB sampling performed within 100 days of disease recurrence displayed overexpression of SPAG6, ST18, PRAME, or XAGE1A at a median of 2 months (range, 0.6 to 9.6 months) before hematologic relapse, whereas MSLN did not reach expression above normal prior to hematologic relapse. Only 1 of 130 (0.8%) follow-up analyses performed in 10 patients in continuous complete remission had transient expression above normal. SPAG6, ST18, PRAME, and XAGE1A expression in PB may predict relapse in childhood AML patients and facilitate MRD monitoring in most patients without a leukemia-specific target., (Copyright © 2021 Association for Molecular Pathology and American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)

Infants with acute lymphoblastic leukaemia (ALL) have a high frequency of central nervous system (CNS) involvement. Flow cytometric analysis of cerebrospinal fluid (CSF) was recently demonstrated to be a sensitive method for detecting CNS involvement in childhood ALL. In the present study, CSF from 14 infants was collected at routine lumbar punctures and analysed by multicolour flow cytometry. At initial diagnosis, leukaemic blasts were detected in CSF by flow cytometry in 11 patients (78·6%) compared to seven patients (50%) by cytospin. Larger studies are needed to determine if CSF flow cytometry has prognostic value in infant ALL., (© 2021 British Society for Haematology and John Wiley & Sons Ltd.)

Background: Laboratory monitoring of mother, fetus, and newborn in hemolytic disease of fetus and newborn (HDFN) aims to guide clinicians and the immunized women to focus on the most serious problems of alloimmunization and thus minimize the consequences of HDFN in general and of anti-D in particular. Here, we present the current approach of laboratory screening and testing for prevention and monitoring of HDFN at the Copenhagen University Hospital in Denmark., Summary: All pregnant women are typed and screened in the 1st trimester. This serves to identify the RhD-negative pregnant women who at gestational age (GA) of 25 weeks are offered a second screen test and a non-invasive fetal RhD prediction. At GA 29 weeks, and again after delivery, non-immunized RhD-negative women carrying an RhD-positive fetus are offered Rh immunoglobulin. If the 1st trimester screen reveals an alloantibody, antenatal investigation is initiated. This also includes RhD-positive women with alloantibodies. Specificity and titer are determined, the fetal phenotype is predicted by non-invasive genotyping based on cell-free DNA (RhD, K, Rhc, RhC, RhE, ABO), and serial monitoring of titer commences. Based on titers and specificity, monitoring with serial peak systolic velocity measurements in the fetal middle cerebral artery to detect anemia will take place. Intrauterine transfusion is given when fetal anemia is suspected. Monitoring of the newborn by titer and survival of fetal red blood cells by flow cytometry will help predict the length of the recovery of the newborn., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2021 by S. Karger AG, Basel.)

Within the International Registry of Childhood Chronic Myeloid Leukemia (CML), we identified 18 patients less than 18 years old at diagnosis of CML who were in the chronic phase and exhibiting a sustained deep molecular response (DMR) to imatinib defined as BCR-ABL1/ABL1 < 0.01% (MR 4 ) for at least two years followed by discontinuation of imatinib. Before discontinuation, the median duration of imatinib was 73.2 months (range, 32-109) and the median duration of MR 4 was 46.2 months (range, 23.9-98.6). Seven patients experienced loss of major molecular response (MMR) 4.1 months (range, 1.9-6.4) after stopping and so restarted imatinib. The median molecular follow-up after discontinuation was 51 months (range, 6-100) for the nine patients without molecular relapse. The molecular free remission rate was 61% (95% CI, 38-83%), 56% (95% CI, 33-79%) and 56% (95% CI, 33-79%) at 6, 12 and 36 months, respectively. Six of the seven children who experienced molecular relapse after discontinuation regained DMR (median, 4.7 months; range, 2.5-18) after restarting imatinib. No withdrawal syndrome was observed. In univariate analysis, age, sex, Sokal and ELTS scores, imatinib treatment and DMR durations before discontinuation had no influence on treatment free remission. These data suggest that imatinib can be safely discontinued in children with sustained MR 4 for at least two years.

Liposomal amphotericin-B (L-AmB) prophylaxis is used in children with leukemia when azoles are contraindicated, but its effect is debated. We reviewed cases of invasive aspergillosis despite L-AmB 2.5 mg/kg twice weekly in children with high-risk leukemia during 2012-2019. Ten (16%) of 62 children had proven or probable aspergillosis. Thus, L-AmB prophylaxis offered insufficient protection for Aspergillus, in particular for Aspergillus flavus., Competing Interests: The authors have no funding or conflicts of interest to disclose., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Pediatric acute myeloid leukemia (AML) is a heterogeneous disease composed of clinically relevant subtypes defined by recurrent cytogenetic aberrations. The majority of the aberrations used in risk grouping for treatment decisions are extensively studied, but still a large proportion of pediatric AML patients remain cytogenetically undefined and would therefore benefit from additional molecular investigation. As aberrant epigenetic regulation has been widely observed during leukemogenesis, we hypothesized that DNA methylation signatures could be used to predict molecular subtypes and identify signatures with prognostic impact in AML. To study genome-wide DNA methylation, we analyzed 123 diagnostic and 19 relapse AML samples on Illumina 450k DNA methylation arrays. We designed and validated DNA methylation-based classifiers for AML cytogenetic subtype, resulting in an overall test accuracy of 91%. Furthermore, we identified methylation signatures associated with outcome in t(8;21)/ RUNX1-RUNX1T1 , normal karyotype, and MLL/KMT2A -rearranged subgroups ( p < 0.01). Overall, these results further underscore the clinical value of DNA methylation analysis in AML.

To detect a change in the probability of a sequence of independent binomial random variables, a variety of asymptotic and exact testing procedures have been proposed. Whenever the sample size or the event rate is small, asymptotic approximations of maximally selected test statistics have been shown to be inaccurate. Although exact methods control the type I error rate, they can be overly conservative due to the discreteness of the test statistics in these situations. We extend approaches by Worsley and Halpern to develop a test that is less discrete to increase the power. Building on ideas from binary segmentation, the proposed test utilizes unused information in the binomial sequences to add a new ordering to test statistics that are of equal value. The exact distributions are derived under side conditions that arise in hypothetical segmentation steps and do not depend on the type of test statistic used (e.g., log likelihood ratio, cumulative sum, or Fisher's exact test). Using the proposed exact segmentation procedure, we construct a change point test and prove that it controls the type-I-error rate at any given nominal level. Furthermore, we prove that the new test is uniformly at least as powerful as Worsley's exact test. In a Monte Carlo simulation study, the gain in power can be remarkable, especially in scenarios with small sample size. Giving a clinical database example about pin site infections and an example assessing publication bias in neuropsychiatric drug research, we demonstrate the wide-ranging applicability of the test., (© 2020 The Authors. Biometrical Journal published by Wiley-VCH GmbH.)

Purpose: Infant acute lymphoblastic leukemia (ALL) is characterized by a high incidence of KMT2A gene rearrangements and poor outcome. We evaluated the value of minimal residual disease (MRD) in infants with KMT2A -rearranged ALL treated within the Interfant-06 protocol, which compared lymphoid-style consolidation (protocol IB) versus myeloid-style consolidation (araC, daunorubicin, etoposide/mitoxantrone, araC, etoposide)., Materials and Methods: MRD was measured in 249 infants by DNA-based polymerase chain reaction of rearranged KMT2A , immunoglobulin, and/or T-cell receptor genes, at the end of induction (EOI) and end of consolidation (EOC). MRD results were classified as negative, intermediate (< 5 × 10 -4 ), and high (≥ 5 × 10 -4 )., Results: EOI MRD levels predicted outcome with 6-year disease-free survival (DFS) of 60.2% (95% CI, 43.2 to 73.6), 45.0% (95% CI, 28.3 to 53.1), and 33.8% (95% CI, 23.8 to 44.1) for infants with negative, intermediate, and high EOI MRD levels, respectively ( P = .0039). EOC MRD levels were also predictive of outcome, with 6-year DFS of 68.2% (95% CI, 55.2 to 78.1), 40.1% (95% CI, 28.1 to 51.9), and 11.9% (95% CI, 2.6 to 29.1) for infants with negative, intermediate, and high EOC MRD levels, respectively ( P < .0001). Analysis of EOI MRD according to the type of consolidation treatment showed that infants treated with lymphoid-style consolidation had 6-year DFS of 78.2% (95% CI, 51.4 to 91.3), 47.2% (95% CI, 33.0 to 60.1), and 23.2% (95% CI, 12.1 to 36.4) for negative, intermediate, and high MRD levels, respectively ( P < .0001), while for myeloid-style-treated patients the corresponding figures were 45.0% (95% CI, 23.9 to 64.1), 41.3% (95% CI, 23.2 to 58.5), and 45.9% (95% CI, 29.4 to 60.9)., Conclusion: This study provides support for the idea that induction therapy selects patients for subsequent therapy; infants with high EOI MRD may benefit from AML-like consolidation (DFS 45.9% v 23.2%), whereas patients with low EOI MRD may benefit from ALL-like consolidation (DFS 78.2% v 45.0%). Patients with positive EOC MRD had dismal outcomes. These findings will be used for treatment interventions in the next Interfant protocol.

Introduction: Chronic myeloid leukemia (CML) is rare in the first two decades of life comprising only 3% of newly diagnosed pediatric and adolescent leukemias. We studied the epidemiologic and clinical features of patients with CML diagnosed at younger than 3 years of age and evaluated treatment and long-term outcome., Method: Data from the International Pediatric I-BFM/CML Registry were retrospectively analyzed using the European LeukemiaNet criteria of the year 2006. Characteristics and treatment outcome of patients <3 years old at diagnosis were evaluated from standardized forms., Results: Twenty-two patients (n = 22/479; 4.6%, male/female:14/8) were enrolled with a median age of 22 months (range, 10-34 m). Major symptoms comprised asthenia (30%), fever (30%), abdominal pain (20%), extramedullary signs (14%), hemorrhage (5%), and weight loss (5%). The extramedullary signs were specified in eight children: blueberry muffin (n = 1), sudden swollen abdomen (n = 1), sustained vomiting (n = 1), and cervical and inguinal lymph nodes (n = 5). Two of five children with cervical and inguinal lymph nodes were categorized as accelerated phase. Overall, 19 of 22 (86%) children were diagnosed in chronic phase, while the remaining three patients were in advanced phase. Median follow-up was 78 months (range, 7-196 m). Twenty-one out of 22 patients initially received imatinib, while one child received IFN + ARA-C. Imatinib was changed to second-line tyrosine kinase inhibitors (TKIs) in 29% of cases. During follow-up, 41% patients underwent stem cell transplantation (SCT). While on TKI, major molecular response (MMR) was achieved in 48% of children. Among the remaining patients, 21% are alive on TKI without MMR and 22% achieved complete molecular response following SCT. Twenty-one of 22 (95%) children are alive, while one patient died of posttransplant complications., Conclusion: This report demonstrates for the first time the efficacy and long-term effects of upfront imatinib in the so far largest cohort of children with CML diagnosed at very young age., (© 2020 Wiley Periodicals LLC.)

Background: Interprofessional education in childhood cancer is a multifaceted field involving multiple healthcare professionals with general and specialised knowledge and skills. Complex treatment, care and rehabilitation require continuous professional development and maintenance of healthcare professionals' competencies in their field of expertise. However, limited knowledge exists in comparing interprofessional and monoprofessional education. Only a few randomised studies have evaluated the effectiveness and efficiency of interprofessional education. The objective of this single-centre, investigator-initiated cluster randomised trial is to study the effect of interprofessional versus monoprofessional case-based learning on healthcare professionals' knowledge of gastrointestinal side effects and attitudes towards team collaboration., Methods: This study will randomise healthcare professionals to participate in either the experimental interprofessional group or the control monoprofessional group of case-based learning. The topic of the case-based intervention will be gastrointestinal side effects, one of six categories identified in a three-round Scandinavian Delphi study as relevant for interprofessional education in childhood cancer. The primary outcome is the self-reported questionnaire Assessment of Interprofessional Team Collaboration Scale. Secondary outcomes are measured by the self-reported questionnaires Readiness for Interprofessional Learning Scale Questionnaire, Safety Attitudes Questionnaire, and knowledge will be evaluated using a multiple-choice quiz. Participants will receive the self-reported questionnaires about 2 weeks before and 1 month after the intervention. On the day of the intervention, participants will answer a multiple-choice quiz before and after the case-based learning. Linear mixed models will be used to compare differences between the two groups in mean scores postintervention, adjusting for preintervention scores., Discussion: This study will provide insight into the differences between interprofessional and monoprofessional case-based learning and how it affects healthcare professionals' knowledge of gastrointestinal side effects and attitudes towards team collaboration., Trial Registration: The intervention was registered at Clinical Trials.gov : NCT04204109 on December 102,019 and with the National Committee on Health Research Ethics: H-19087506 December 112,019 and the Danish Data Protection Agency: P-2019-637 October 152,019.

Background: Chronic myeloid leukaemia (CML) is a rare disease in children. The frequency and outcome of children evolving to accelerated phase (AP) or blastic phase (BP) under treatment with imatinib is unknown. The aim of the current study is to assess the incidence of progression from CML in chronic phase with imatinib frontline in a paediatric setting and describe the management and outcome of these patients., Patients and Methods: In the I-CML-Ped Study database (www.clinicaltrials.gov, #NCT01281735), 19 of 339 paediatric patients in chronic phase treated with imatinib in the frontline evolved to CML-AP or CML-BP., Results: With a median follow-up of 38 months (range: 2-190 months), the cumulative incidence of progression at 1 and 3 years was 3% (confidence interval [CI] 95%: 1-5%) and 7% (CI 95%: 4-11%), respectively. We observed a large predominance of lymphoid-BP (70%) over myeloid-BP (30%) with imatinib in frontline therapy. Sixteen patients underwent haematopoietic stem cell transplantation, and eight were treated with a tyrosine kinase inhibitor after transplant. Only the transplanted patients are alive. The 5-year overall survival rate of children with CML-AP/BP is 44%, with no statistical difference between the lymphoid-BP and myeloid-BP outcome., Conclusion: Children evolving to AP or BP under treatment with imatinib have a very poor prognosis with an overall survival under 50%, much worse than children with advanced phase at diagnosis., Competing Interests: Conflict of interest statement The authors declare no competing financial interests., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Serial assessments of measurable (or minimal) residual disease (MRD) by qPCR may identify nascent relapse in children with acute myeloid leukaemia (AML) and enable pre-emptive therapy. We investigated the kinetics and prognostic impact of recurrent fusion transcripts (RUNX1-RUNX1T1, CBFB-MYH11, KMT2A-MLLT3 or KMT2A-ELL) in 774 post-induction samples from bone marrow (BM, 347) and peripheral blood (PB, 427) from 75 children with AML. BM MRD persistence during consolidation did not increase the risk of relapse, and MRD at therapy completion did not correlate to outcome (HR = 0·64/MRD log reduction (CI: 0·32-1·26), P = 0·19). In contrast, 8/8 patients with detectable MRD in PB after first consolidation relapsed. Persistence (n = 4) and shifting from negative to positive (n = 10) in PB during follow-up predicted relapse in 14/14 patients. All 253 PB samples collected during follow-up from 36 patients in continuous complete remission were MRD negative. In core-binding factor AML, persistent low-level MRD positivity in BM during follow-up was frequent but an increment to above 5 × 10 -4 heralded subsequent haematological relapse in 12/12 patients. We demonstrate that MRD monitoring in PB after induction therapy is highly informative and propose an MRD increment above 5 × 10 -4 in PB and BM as a definition of molecular relapse since it always leads to haematological relapse., (© 2020 British Society for Haematology and John Wiley & Sons Ltd.)

Background: Complex treatment, care and rehabilitation require continuous healthcare professional development and maintenance of competencies in collaboration with other professionals. Interprofessional education in childhood cancer involves several groups of healthcare professionals with both general and specific knowledge and skills., Objective: To establish consensus on content and interprofessional learning objectives for an interprofessional education in childhood cancer., Design: A three-round Delphi survey in Scandinavian childhood cancer departments., Participants: Healthcare professionals appointed by their head of departments and head nurses based on their profession and their involvement in continuing professional development., Main Outcome Measures: A prioritised list of interprofessional learning objectives with a mean score of ≥3 on a five-point scale (1=not relevant, 5=extremely relevant)., Results: 12 childhood cancer departments participated with 30 healthcare professionals: 11 nurses, 10 medical doctors, 5 social workers, 2 physiotherapists and 2 pedagogues. In total, 28 (93%), 25 (83%) and 22 (73%) completed the first, second and third round, respectively. In the first round, we asked open-ended questions and used directed content analysis to analyse 386 statements. We formulated 170 interprofessional learning objectives in six categories: (1) acute life-threatening situations, (2) gastrointestinal toxicities and side effects, (3) pain, (4) palliation, (5) play and activity, and (6) prescription and administration of medicine. The second round resulted in 168 interprofessional learning objectives receiving a mean score of ≥3 on a five-point scale. Final agreement in the third round resulted in a prioritised list of 168 learning objectives., Conclusions: Consensus on content and interprofessional learning objectives for an interprofessional education in childhood cancer was established across five groups of healthcare professionals in three countries. Some learning objectives are generic and can be applied in settings other than childhood cancer, where healthcare professionals collaborate to provide patients and families optimal treatment and care., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Associations between body mass index (BMI), outcome, and leukemia-related factors in children with acute myeloid leukemia (AML) remain unclear. We investigated associations between pretherapeutic BMI, cytogenetic abnormalities, and outcome in a large multinational cohort of children with AML., Methods: We included patients, age 2-17 years, diagnosed with de novo AML from the five Nordic countries (2004-2016), Hong Kong (2007-2016), the Netherlands and Belgium (2010-2016), and Canada and USA (1995-2012). BMI standard deviations score for age and sex was calculated and categorized according to the World Health Organization. Cumulative incidence functions, Kaplan-Meier estimator, Cox regression, and logistic regression were used to investigate associations., Results: In total, 867 patients were included. The median age was 10 years (range 2-17 years). At diagnosis, 32 (4%) were underweight, 632 (73%) were healthy weight, 127 (15%) were overweight, and 76 (9%) were obese. There was no difference in relapse risk, treatment-related mortality or overall mortality across BMI groups. The frequency of t(8;21) and inv(16) increased with increasing BMI. For obese patients, the sex, age, and country adjusted odds ratio of having t(8;21) or inv(16) were 1.9 (95% confidence interval (CI) 1.1-3.4) and 2.8 (95% CI 1.3-5.8), respectively, compared to healthy weight patients., Conclusions: This study did not confirm previous reports of associations between overweight and increased treatment-related or overall mortality in children. Obesity was associated with a higher frequency of t(8;21) and inv(16). AML cytogenetics appear to differ by BMI status., (© 2019 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.)

Purpose: Despite improved treatment and care, children and adolescents diagnosed with cancer continue to die, while many of those cured are burdened by treatment-related sequelae. The best clinical management of children and adolescents with cancer depends on healthcare professionals with various skills and expertise. Complex treatment, care and rehabilitation require collaboration between healthcare professionals. The purpose of this scoping review is to identify and evaluate existing interprofessional education in paediatric cancer., Methods: We utilised the scoping review methodology and searched PubMed, Scopus and Education Resources Information Center. Inclusion criteria were postgraduate studies targeting more than one profession and evaluation of the educational intervention. We applied Kirkpatrick's modified interprofessional education outcomes model to systematise outcomes., Results: Of 418 references, nine studies fulfilled the inclusion criteria. The design, strategy and content of all the studies were heterogeneous. None of the interprofessional educations systematically evaluated knowledge, skills, attitudes or the effects on patient outcomes or quality of care., Conclusion: There is a lack of well-structured, interprofessional education in paediatric cancer that has undergone evaluation. Paediatric cancer may benefit from systematic education and evaluation frameworks since interprofessional education could potentially strengthen the treatment, care and rehabilitation for children and adolescents with cancer.

Purpose: Infant acute lymphoblastic leukemia (ALL) is characterized by KMT2A ( MLL ) gene rearrangements and coexpression of myeloid markers. The Interfant-06 study, comprising 18 national and international study groups, tested whether myeloid-style consolidation chemotherapy is superior to lymphoid style, the role of stem-cell transplantation (SCT), and which factors had independent prognostic value., Materials and Methods: Three risk groups were defined: low risk (LR): KMT2A germline; high risk (HR): KMT2A -rearranged and older than 6 months with WBC count 300 × 10 9 /L or more or a poor prednisone response; and medium risk (MR): all other KMT2A -rearranged cases. Patients in the MR and HR groups were randomly assigned to receive the lymphoid course low-dose cytosine arabinoside [araC], 6-mercaptopurine, cyclophosphamide (IB) or experimental myeloid courses, namely araC, daunorubicin, etoposide (ADE) and mitoxantrone, araC, etoposide (MAE)., Results: A total of 651 infants were included, with 6-year event-free survival (EFS) and overall survival of 46.1% (SE, 2.1) and 58.2% (SE, 2.0). In West European/North American groups, 6-year EFS and overall survival were 49.4% (SE, 2.5) and 62.1% (SE, 2.4), which were 10% to 12% higher than in other countries. The 6-year probability of disease-free survival was comparable for the randomized arms (ADE+MAE 39.3% [SE 4.0; n = 169] v IB 36.8% [SE, 3.9; n = 161]; log-rank P = .47). The 6-year EFS rate of patients in the HR group was 20.9% (SE, 3.4) with the intention to undergo SCT; only 46% of them received SCT, because many had early events. KMT2A rearrangement was the strongest prognostic factor for EFS, followed by age, WBC count, and prednisone response., Conclusion: Early intensification with postinduction myeloid-type chemotherapy courses did not significantly improve outcome for infant ALL compared with the lymphoid-type course IB. Outcome for infant ALL in Interfant-06 did not improve compared with that in Interfant-99.

Background: Supportive-care use of granulocyte colony-stimulating factor (G-CSF) in pediatric acute myeloid leukemia (AML) remains controversial due to a theoretical increased risk of relapse and limited impact on neutropenic complications. We describe the use of G-CSF in patients treated according to NOPHO-AML 2004 and DB AML-01 and investigated associations with relapse., Procedure: Patients diagnosed with de novo AML completing the first week of therapy and not treated with hematopoietic stem cell transplantation in the first complete remission were included (n = 367). Information on G-CSF treatment after each course (yes/no) was registered prospectively in the study database and detailed information was gathered retrospectively from each center. Descriptive statistics were used to describe G-CSF use and Cox regression to assess the association between G-CSF and risk of relapse., Results: G-CSF as supportive care was given to 128 (35%) patients after 268 (39%) courses, with a large variation between centers (0-93%). The use decreased with time-the country-adjusted odds ratio was 0.8/diagnostic year (95% confidence interval [CI] 0.7-0.9). The median daily dose was 5 μg/kg (range 3-12 μg/kg) and the median cumulative dose was 75 μg/kg (range 7-1460 μg/kg). Filgrastim was used in 82% of G-CSF administrations and infection was the indication in 44% of G-CSF administrations. G-CSF was associated with increased risk of relapse-the adjusted hazard ratio was 1.5 (95% CI 1.1-2.2)., Conclusions: G-CSF as supportive care was used in a third of patients, and use decreased with time. Our results indicate that the use of G-CSF may be associated with an increased risk of relapse., (© 2019 Wiley Periodicals, Inc.)

Acute lymphoblastic leukemia (ALL) is a rare disease in infants. Asparaginase is an essential part of the treatment, and there Acute is a need to evaluate the efficiency and safety of this drug in this age group. We evaluated the pharmacokinetics of intramuscularly administered native E. coli asparaginase (Asparaginase Medac ® ) and PEG-asparaginase (Oncaspar ® ) as well as hypersensitivity reactions during treatment in Interfant-06 ( www.clinicaltrials.gov : NCT01025804). All patients without hypersensitivity had sufficiently high enzyme activity levels during treatment with both preparations. Patients with hypersensitivity reactions during treatment, characterized by the presence of either or not of clinical symptoms and no measurable enzyme activity, received ineffective therapy. For optimization of the bad prognosis in infant ALL, therapeutic drug monitoring should be performed for identification of patients who should be switched to a different asparaginase preparation because of inactivation of the drug.

Background: Measurable/minimal residual disease (MRD) monitoring can predict imminent hematological relapse in acute myeloid leukemia (AML). The majority of childhood AML patients do not harbor fusion genes or mutations applicable as MRD markers and overexpression of Wilms tumor gene 1 (WT1) may constitute a useful monitoring target. However, age-specific reference values in healthy hematopoiesis and standardization of WT1 assessment are prerequisites for clinical utility., Procedure: We investigated WT1 expression across age in hematologically healthy controls (n = 109), during suspected infection (n = 90) and bone marrow (BM) regeneration (n = 13). WT1 expression in AML at diagnosis (n = 91) and during follow-up (n = 30) was compared with age-specific reference values., Results: WT1 expression correlated with age and showed higher levels in both BM and peripheral blood (PB) in children compared with adults (P < 0.001 and P = 0.01). WT1 expression from healthy hematopoiesis was lower in PB compared with BM (WT1 BM /WT1 PB  = 8.6, 95% CI: 5.3-13.7) and not influenced by infection nor BM regeneration. At AML diagnosis, 66% had more than 20-fold WT1 overexpression in PB or BM (PB 74%; BM 45%). WT1 was quantified in 279 PB samples during follow-up. All 11 patients with PB sampling within 4 months of disease recurrence displayed WT1 overexpression by a median of 1.9 months (range, 0.7-9.7) before hematological relapse., Conclusions: This study defines child-specific reference values for WT1 expression in healthy hematopoiesis and demonstrates that WT1 expression in PB is a useful post-treatment monitoring tool in childhood AML. Based on these observations, we propose definitions for childhood AML molecular relapse using WT1 overexpression., (© 2019 Wiley Periodicals, Inc.)

This international study aimed to assess the effect of imatinib discontinuation in paediatric patients with chronic myeloid leukaemia (CML) after deep molecular remission (DMR) had been achieved and maintained for at least 2 years. The primary endpoint of this analysis was the molecular relapse-free survival, estimated by the non-parametric Kaplan-Meier method. Major endpoint was the estimated rate of patients without molecular relapse at 6 months. Fourteen patients were enrolled; 4 patients maintained DMR with a follow-up of 24 (two patients), 34 and 66 months, respectively, whereas 10 patients relapsed. All molecular relapses occurred within 6 months (median 3 months, range 1-6) after imatinib discontinuation. The overall probability of maintaining DMR at 6 months was 28·6%. No parameters associated with molecular relapse could be identified. Keeping in mind the rarity of paediatric CML, which contributed to the small size of the cohort, our findings illustrate that imatinib cessation after sustained DMR is successful in only limited numbers of patients, whereas much higher rates are reported in adult patients. Further research is needed to extend the cohort of paediatric CML patients who might achieve treatment-free remission with an ideal prerequisite of predicting the occurrence of molecular relapse l after imatinib cessation., (© 2019 British Society for Haematology and John Wiley & Sons Ltd.)

Data on occurrence, genetic characteristics and prognostic impact of complex and monosomal karyotype (CK/MK) in children with acute myeloid leukaemia (AML) are scarce. We studied CK and MK in a large unselected cohort of childhood AML patients diagnosed and treated according to Nordic Society for Paediatric Haematology and Oncology (NOPHO)-AML protocols 1993-2015. In total, 800 patients with de novo AML were included. CK was found in 122 (15%) and MK in 41 (5%) patients. CK and MK patients were young (median age 2·1 and 3·3 years, respectively) and frequently had FAB M7 morphology (24% and 22%, respectively). Refractory disease was more common in MK patients (15% vs. 4%) and stem cell transplantation in first complete remission was more frequent (32% vs. 19%) compared with non-CK/non-MK patients. CK showed no association with refractory disease but was an independent predictor of an inferior event-free survival (EFS; hazard ratio [HR] 1·43, P = 0·03) and overall survival (OS; HR 1·48, P = 0·01). MK was associated with a poor EFS (HR 1·57, P = 0·03) but did not show an inferior OS compared to non-MK patients (HR 1·14, P = 0·62). In a large paediatric cohort, we characterized AML with non-recurrent abnormal karyotype and unravelled the adverse impact of CK and MK on prognosis., (© 2018 British Society for Haematology and John Wiley & Sons Ltd.)

Relationships among skeletal age (SA), body size and fundamental motor skills (FMS) and motor performance were considered in 155 boys and 159 girls 3-6 years of age. Stature and body mass were measured. SA of the hand-wrist was assessed with the Tanner-Whitehouse II 20 bone method. The Test of Gross Motor Development, 2nd edition (TGMD-2), and the Preschool Test Battery were used, respectively, to assess FMS and motor performance. Based on hierarchical regression analyses, the standardized residuals of SA on chronological age (SAsr) explained a maximum of 6.1% of the variance in FMS and motor performance in boys (ΔR 2 3 , range 0.0%-6.1%) and a maximum of 20.4% of the variance in girls (ΔR 2 3 , range 0.0%-20.4%) over that explained by body size and interactions of SAsr with body size (step 3). The interactions of the SAsr and stature and body mass (step 2) explained a maximum of 28.3% of the variance in boys (ΔR 2 2 , range 0.5%-28.3%) and 16.7% of the variance in girls (ΔR 2 2 , range 0.7%-16.7%) over that explained by body size alone. With the exception of balance, relationships among SAsr and FMS or motor performance differed between boys and girls. Overall, SA per se or interacting with body size had a relatively small influence in FMS and motor performance in children 3-6 years of age., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Background: Children with acute myeloid leukemia (AML) treated similarly show different toxicity and leukemic responses. We investigated associations between neutrophil recovery time after the first induction course, infection and relapse in children treated according to NOPHO-AML 2004 and DB AML-01., Procedure: Newly diagnosed patients with AML with bone marrow blast <5% between day 15 after the start of the treatment and the start of second induction course, and in complete remission after the second induction course were included (n = 279). Neutrophil recovery time was defined as the time from the start of the course to the last day with absolute neutrophil count <0.5 × 10 9 /l. Linear and Cox regressions were used to investigate associations., Results: Neutrophil recovery time after the first induction course was positively associated with neutrophil recovery time after the remaining courses, and longer neutrophil recovery time (≥25 days) was associated with increased risk of grade 3-4 infections (hazard ratio 1.4, 95% confidence interval [CI], 1.1-1.8). Longer neutrophil recovery time after the first induction (>30 days) was associated with the increased risk of relapse (5-year cumulative incidence: 48% vs. 42%, hazard ratio 1.7, 95% CI, 1.1-2.6) for cases not treated with hematopoietic stem cell transplantation in first complete remission., Conclusion: Longer neutrophil recovery time after the first induction course was associated with grade 3-4 infections and relapse. If confirmed, this knowledge could be incorporated into risk stratification strategies in pediatric AML., (© 2018 Wiley Periodicals, Inc.)

A total of 156 patients (age range 1.3-18.0 years, median 13.2 years; 91 (58.3%) male) with newly diagnosed CML (N = 146 chronic phase (CML-CP), N = 3 accelerated phase (CML-AP), N = 7 blastic phase (CML-BP)) received imatinib up-front (300, 400, 500 mg/m 2 , respectively) within a prospective phase III trial. Therapy response, progression-free survival, causes of treatment failure, and side effects were analyzed in 148 children and adolescents with complete data. Event-free survival rate by 18 months for patients in CML-CP (median follow-up time 25 months, range: 1-120) was 97% (95% CI, 94.2-99.9%). According to the 2006 ELN-criteria complete hematologic response by month 3, complete cytogenetic response (CCyR) by month 12, and major molecular response (MMR) by month 18 were achieved in 98, 63, and 59% of the patients, respectively. By month 36, 86% of the patients achieved CCyR and 74% achieved MMR. Thirty-eight patients (27%) experienced imatinib failure because of unsatisfactory response or intolerance (N = 9). In all, 28/148 patients (19%) underwent stem cell transplantation (SCT). In the SCT sub-cohort 2/23 patients diagnosed in CML-CP, 0/1 in CML-AP, and 2/4 in CML-BP, respectively, died of relapse (N = 3) or SCT-related complications (N = 2). This large pediatric trial extends and confirms data from smaller series that first-line imatinib in children is highly effective.

The t(7;12)(q36;p13) (MNX1/ETV6) is not included in the WHO classification but has been described in up to 30% of acute myeloid leukemia (AML) in children <2 years and associated with a poor prognosis. We present the clinical and cytogenetics characteristics of AML cases with t(7;12)(p36;p13). A literature review identified 35 patients with this translocation, published between 2000 and 2015. Outcome data were available in 22 cases. The NOPHO-AML (Nordic Society for Pediatric Hematology and Oncology) database contained 651 patients with AML from 1993 to 2014 and seven (1.1%) had the translocation. The t(7;12) was only present in patients <2 years of age (median age 6 months) but none was diagnosed as newborn. These patients constituted 4.3% of the patients <2 years of age. There was a strong association with trisomy 19 (literature: 86%, NOPHO: 100%) and +8 (literature: 19%, NOPHO: 14%). Seventeen of 22 patients from the literature with t(7;12) and four of seven patients from the NOPHO database suffered from relapse. The patients with t(7;12) had a 3-year event free survival of 24% (literature) vs. 43% (NOPHO) and a 3-year overall survival of 42% (literature) vs. 100% (NOPHO). None of the NOPHO patients was treated with hematopoietic stem cell transplantation (HSCT) in first complete remission. Relapse was frequent but the salvage rate using HSCT was high. We conclude that t(7;12)(q36;13) is a unique subgroup of childhood AML with presentation before 2 years of age with most cases being associated with +19., (© 2018 Wiley Periodicals, Inc.)

Background: Urinary incontinence (UI) is a distressing condition affecting at least 5 million women in England and Wales. Traditionally, physiotherapy for UI comprises pelvic floor muscle training, but although evidence suggests this can be effective it is also recognised that benefits are often compromised by patient motivation and commitment. In addition, there is increasing recognition that physical symptoms alone are poor indicators of the impact of incontinence on individuals' lives. Consequently, more holistic approaches to the treatment of UI, such as Modified Pilates (MP) have been recommended. This study aimed to provide preliminary findings about the effectiveness of a 6-week course of MP classes as an adjunct to standard physiotherapy care for UI, and to test the feasibility of a randomised controlled trial (RCT) design., Methods: The study design was a single centre pilot RCT, plus qualitative interviews. 73 women referred to Women's Health Physiotherapy Services for UI at Colchester Hospital University NHS Foundation Trust were randomly assigned to two groups: a 6-week course of MP classes in addition to standard physiotherapy care (intervention) or standard physiotherapy care only (control). Main outcome measures were self-reported UI, quality of life and self-esteem at baseline (T1), completion of treatment (T2), and 5 months after randomisation (T3). Qualitative interviews were conducted with a subgroup at T2 and T3. Due to the nature of the intervention blinding of participants, physiotherapists and researchers was not feasible., Results: Post-intervention data revealed a range of benefits for women who attended MP classes and who had lower symptom severity at baseline: improved self-esteem (p = 0.032), decreased social embarrassment (p = 0.026) and lower impact on normal daily activities (p = 0.025). In contrast, women with higher symptom severity showed improvement in their personal relationships (p = 0.017). Qualitative analysis supported these findings and also indicated that MP classes could positively influence attitudes to exercise, diet and wellbeing., Conclusions: A definitive RCT is feasible but will require a large sample size to inform clinical practice., Trial Registration: ISRCTN74075972 Registered 12/12/12 (Retrospectively registered).

Combining multiple classifiers, known as ensemble methods, can give substantial improvement in prediction performance of learning algorithms especially in the presence of non-informative features in the data sets. We propose an ensemble of subset of k NN classifiers, ES k NN, for classification task in two steps. Firstly, we choose classifiers based upon their individual performance using the out-of-sample accuracy. The selected classifiers are then combined sequentially starting from the best model and assessed for collective performance on a validation data set. We use bench mark data sets with their original and some added non-informative features for the evaluation of our method. The results are compared with usual k NN, bagged k NN, random k NN, multiple feature subset method, random forest and support vector machines. Our experimental comparisons on benchmark classification problems and simulated data sets reveal that the proposed ensemble gives better classification performance than the usual k NN and its ensembles, and performs comparable to random forest and support vector machines.

Background: The prognostic significance of extramedullary leukemia (EML) in childhood acute myeloid leukemia is not clarified., Procedure: This population-based study included 315 children from the NOPHO-AML 2004 trial., Results: At diagnosis, 73 (23%) patients had EML: 39 (12%) had myeloid sarcoma, 22 (7%) had central nervous system disease, and 12 (4%) had both. EML was associated with young age (median age: 2.6 years), a high white blood cell count (median: 40 × 10 9 /l), M5 morphology (40%), and 11q23/MLL (KMT2A) rearrangements (34%). No patient received involved field radiotherapy. Five-year event-free survival did not differ significantly between the EML and the non-EML patients (54% vs. 45%, P = 0.57), whereas 5-year overall survival (OS) was significantly lower in the EML group (64% vs. 73%, P = 0.04). The risk of induction death was significantly higher for EML patients (8% vs. 1%, P = 0.002). There was a trend toward a lower risk of relapse for EML patients (5-year cumulative incidence of relapse 33% vs. 49%, P = 0.16). Traumatic lumbar puncture did not adversely affect survival in this cohort., Conclusions: EML was associated with increased risk of induction death impacting the OS. No patients relapsed at the primary site of the myeloid sarcoma despite management without radiotherapy., (© 2017 Wiley Periodicals, Inc.)

The EUTOS Long-Term Survival score was tested in 350 children with chronic myeloid leukemia in first chronic phase treated with imatinib and registered in the International Registry for Childhood Chronic Myeloid Leukemia. With a median follow up of 3 years (range, 1 month to 6 years) progression and/or death (whichever came first) occurred in 23 patients. For the entire cohort of patients the 5-year progression-free survival rate was 92% (95% CI: 87%-94%) and the 5-year survival accounting for chronic myeloid leukemia deaths was 97% (95% CI: 94%-99%). Of the 309 patients allocated to low (n=199), intermediate (n=68) and high (n=42) risk groups by the EUTOS Long-Term Survival score, events (progression and/or death) occurred in 6.0%, 8.8% and 26.2%, respectively. Estimates of the 5-year progression-free survival rates according to these three risk groups were 96% (95% CI: 92%-98%), 88% (95% CI: 76%-95%) and 67% (95% CI: 48%-81%), respectively. Differences in progression-free survival according to these risk groups were highly significant ( P <0.0001, overall). The EUTOS Long-Term Survival score showed better differentiation of progression-free survival than the Sokal (<45 years), Euro and EUTOS scores in children and adolescents with chronic myeloid leukemia and should be considered in therapeutic algorithms. (Trial registered at: www.clinicaltrials.gov NCT01281735) ., (Copyright© 2017 Ferrata Storti Foundation.)

Background: In the adult population with newly diagnosed chronic myeloid leukemia (CML), variant translocations are usually not considered to be impairing the prognosis, whereas some additional cytogenetic abnormalities (ACAs) are associated with a negative impact on survival. Because of the rarity of CML in the pediatric population, such abnormalities have not been investigated in a large group of children with CML., Methods: The prognostic relevance of variant t(9;22) and ACAs at diagnosis was assessed in 301 children with CML in the chronic phase who were enrolled in the International Registry for Chronic Myeloid Leukemia in Children and Adolescents., Results: Overall, 19 children (6.3%) presented with additional cytogenetic findings at diagnosis: 5 children (1.7%) had a variant t(9;22) translocation, 13 children (4.3%) had ACAs, and 1 had both. At 3 years, for children with a classic translocation, children with ACAs, and children with a variant t(9;22) translocation who were treated with imatinib as frontline therapy, the probability of progression-free survival (PFS) was 95% (95% confidence interval [CI], 91%-97%), 100%, and 75% (95% CI, 13%-96%), respectively, and the probability of overall survival (OS) was 98% (95% CI, 95%-100%), 100% (95% CI, 43%-98%), and 75% (95% CI, 13%-96%), respectively. No statistical difference was observed between the patients with classic cytogenetic findings and those with additional chromosomal abnormalities in terms of PFS and OS., Conclusions: In contrast to adults with CML, additional chromosomal abnormalities observed at diagnosis do not seem to have a significant prognostic impact. Cancer 2017;123:3609-16. © 2017 American Cancer Society., (© 2017 American Cancer Society.)

Given that 30-40% of children with acute myeloid leukaemia (AML) relapse after primary therapy it is important to define prognostic factors and identify optimal therapy. From 1993 to 2012, 543 children from the Nordic countries were treated according to two consecutive protocols: 208 children relapsed. The influence of disease characteristics, first line treatment, relapse therapy and duration of first remission on outcome was analysed. Second complete remission (CR2) was achieved in 146 (70%) patients. Estimated 5-year overall survival (OS 5y ) was 39 ± 4% for the whole group and 43 ± 4% for the 190 patients given re-induction therapy, of whom 76% received regimens that included fludarabine, cytarabine (FLA) ± anthracyclines, 18% received Nordic Society for Paediatric Haematology and Oncology (NOPHO) upfront blocks and 5% received other regimens. Late relapse ≥1 year from diagnosis, no allogeneic stem cell transplantation (SCT) in first remission and core binding factor AML were independent favourable prognostic factors for survival. For the 128 children (124 in CR2) that received SCT as consolidation therapy after relapse, OS 5y was 61 ± 5%. Four of 19 children (21%) survived without receiving SCT as part of relapse therapy. Our data show that intensive re-induction followed by SCT can give cure rates of 40% in children with relapsed AML., (© 2017 John Wiley & Sons Ltd.)

Hyperleucocytosis in paediatric acute myeloid leukaemia (AML) is associated with increased morbidity and mortality. We studied hyperleucocytosis in 890 patients with AML aged 0-18 years registered in the Nordic Society of Paediatric Haematology and Oncology (NOPHO) registry, with special focus on very high white blood cell counts (WBC >200 × 10/l). Eighty-six patients (10%) had WBC 100-199 × 10 9 /l and 57 (6%) had WBC ≥200 × 10 9 /l. Patients with WBC ≥200 × 10 9 /l had a high frequency of t(9;11) and a paucity of trisomy 8. Due to the high frequency of deaths within the first 2 weeks (30% vs. 1% for all others), overall survival in this group was inferior to patients with WBC <200 × 10 9 /l (39% vs. 61%). Main cause of early death was intracranial haemorrhage and leucostasis. Twenty-six per cent of these patients never started antileukaemic protocol therapy. Leukapheresis or exchange transfusion was used in 24% of patients with hyperleucocytosis without impact on survival. Patients with hyperleucocytosis surviving the first week had identical survival as patients with lower WBC. We conclude that death within the first days after diagnosis is the major challenge in patients with high WBC and advocate rapid initiation of intensive chemotherapy., (© 2017 John Wiley & Sons Ltd.)

Background: Random forests are successful classifier ensemble methods consisting of typically 100 to 1000 classification trees. Ensemble pruning techniques reduce the computational cost, especially the memory demand, of random forests by reducing the number of trees without relevant loss of performance or even with increased performance of the sub-ensemble. The application to the problem of an early detection of glaucoma, a severe eye disease with low prevalence, based on topographical measurements of the eye background faces specific challenges., Objectives: We examine the performance of ensemble pruning strategies for glaucoma detection in an unbalanced data situation., Methods: The data set consists of 102 topographical features of the eye background of 254 healthy controls and 55 glaucoma patients. We compare the area under the receiver operating characteristic curve (AUC), and the Brier score on the total data set, in the majority class, and in the minority class of pruned random forest ensembles obtained with strategies based on the prediction accuracy of greedily grown sub-ensembles, the uncertainty weighted accuracy, and the similarity between single trees. To validate the findings and to examine the influence of the prevalence of glaucoma in the data set, we additionally perform a simulation study with lower prevalences of glaucoma., Results: In glaucoma classification all three pruning strategies lead to improved AUC and smaller Brier scores on the total data set with sub-ensembles as small as 30 to 80 trees compared to the classification results obtained with the full ensemble consisting of 1000 trees. In the simulation study, we were able to show that the prevalence of glaucoma is a critical factor and lower prevalence decreases the performance of our pruning strategies., Conclusions: The memory demand for glaucoma classification in an unbalanced data situation based on random forests could effectively be reduced by the application of pruning strategies without loss of performance in a population with increased risk of glaucoma.

Treatment for pediatric acute myeloid leukemia is very toxic and the association between outcome and age and Body Mass Index is unclear. We investigated effect of age and Body Mass Index on toxicity and survival in pediatric acute myeloid leukemia. We studied all patients who completed first induction course of NOPHO-AML 2004 (n=318). Toxicity following induction and consolidation courses (n=6) was analyzed. The probabilities of toxicity and death were determined using time-to-event analyses with Cox multivariate proportional hazard regression for comparative analyses. Age 10-17 years was associated with sepsis with hypotension [hazard ratio 2.3 (95% confidence interval 1.1-4.6)]. Being overweight (>1 standard deviation) was associated with requiring supplemental oxygen [1.9 (1.0-3.5)]. The 5-year event-free and overall survival were 47% and 71%. Children aged 10-17 years showed a trend for inferior 5-year overall survival compared to children aged 2-9 (64% vs. 76%; P=0.07). Infants showed a trend for superior 5-year event-free survival (66% vs. 43%; P=0.06). Overweight children aged 10-17 years showed a trend for superior survival [5-year event-free survival 59% vs. 40% (P=0.09) and 5-year overall survival 78% vs. 56% (P=0.06)] compared to healthy weight children aged 10-17 years. In conclusion, children aged 10-17 years and overweight children had a higher risk of grade 3-4 toxicity. Children aged 10-17 years showed inferior survival, but, unexpectedly, in this age group overweight children tended to have increased survival. This suggests different pharmacokinetics of chemotherapeutic drugs in adolescents and warrants further studies., (Copyright© Ferrata Storti Foundation.)