Shlomit Barzilai‐Birenboim

A streamlined, sensitive, and universal molecular method for MRD detection in pediatric AML remains an unmet clinical need. Here, we propose a novel approach based on tracking somatic non‐coding passenger variants. Using whole‐genome sequencing (WGS) of diagnostic bone marrow DNA, we identify patient‐specific somatic passenger variants, which we term “leukemia‐specific passenger variants” (LSPVs). Single‐cell DNA proteogenomic analyses demonstrate that LSPVs are specific and robust markers of leukemic cells, present across the entire leukemic cell population. Moreover, we show that LSPVs are accurate markers of disease burden, stable from diagnosis to relapse. Importantly, LSPVs can be detected in all patients, suggesting the universal applicability of this approach. Leveraging these findings, we developed DAISY‐MRD, a streamlined WGS‐based MRD method that does not rely on the presence of specific trackable genetic aberrations and does not require tailored assay design, making it simple, efficient, and feasible in clinical settings.

High-dose methotrexate (HDMTX) is a cornerstone of contemporary treatment protocols for both pediatric and adult acute lymphoblastic leukemia (ALL); however, up to 4% of children and 15% of adults develop renal toxicity with severely delayed MTX elimination (DME). Evidencebased guidance on re-exposure after DME is lacking, and omission of further HDMTX may compromise anti-leukemic efficacy and potentially increase the risk of relapse. This study, conducted within the Ponte di Legno international toxicity working group, aimed to evaluate the safety of HDMTX re-challenge in pediatric patients after DME. National investigators from 12 countries provided case-level data on initial DME events and subsequent HDMTX re-exposures via structured questionnaires. Data from 189 patients treated for ALL who experienced DME were analyzed, of whom 143 were subsequently re-exposed to HDMTX. Clinical toxicities after the initial DME included gastrointestinal complications (vomiting, diarrhea, mucositis), infections, and neurological events (encephalopathy, seizures, MTX stroke-like syndrome). Laboratory toxicities comprised cytopenias and hepatic abnormalities. Two patients transiently required dialysis. DME led to chemotherapy modifications in 73% of the patients. After reexposure, toxicities were similar in spectrum, self-limited, and non-fatal. Twenty children (14%) developed recurrent DME, including three with two additional episodes. Recurrent DME could not be predicted by clinical, pharmacokinetic, or demographic variables, nor by uniform MTX dose reduction during re-exposure. In conclusion, re-exposure to HDMTX following DME is feasible and generally well tolerated, although the risk of recurrence is increased. Re-challenge should be considered once renal function has normalized, with careful monitoring and individualized dose adjustment.

Background: Granulocyte transfusions (GTXs) are used in neutropenic pediatric hemato‐oncology patients with infections unresponsive to antimicrobial therapy, but their clinical benefit remains uncertain.Methods: We retrospectively reviewed all pediatric patients who received GTXs between 2013 and 2023 at a tertiary medical center. We assessed associations between GTX administration, absolute neutrophil count (ANC) increment, and C‐reactive protein (CRP) reduction as a surrogate marker of treatment response.Results: Forty‐nine patients received 312 GTXs across 56 episodes: 47 for therapeutic use during active infection and nine for secondary prophylaxis. Higher ANC increments were observed after transfusions containing ≥0.6 × 10⁹ neutrophils/kg from same‐day collections. ANC rises were transient, typically declining within 24 hours. CRP levels decreased significantly after the first GTX (p = 0.001) and more markedly by the end of treatment (p < 0.001). ANC increment was significantly associated with CRP reduction (p = 0.006). GTX‐related adverse events occurred in 3% of transfusions. Infection‐related mortality was 17% in the treatment group, while no severe infections occurred in the secondary prophylaxis group.Conclusions: GTXs appear to be a safe adjunctive therapy in high‐risk neutropenic children with severe infections. The observed correlation between ANC increment and CRP reduction supports a potential therapeutic effect and warrants further prospective evaluation.

Background: With improving childhood cancer cure rates, there is a growing focus on the long‐term health and well‐being of survivors. School reintegration is crucial for their rehabilitation and psychosocial adaptation, yet little is known about school violence and bullying faced by cancer survivors upon their return. Aims: This study aimed to investigate the prevalence and forms of school bullying against childhood acute lymphoblastic leukemia (ALL) survivors, identifying risk and protective factors. Methods: ALL survivors aged 6–18 years were assessed through interviews and questionnaires. A paired comparison group of healthy students was recruited from their classrooms. Results: The study included 70 students from grades 6–12 (mean age 14.9 ± 1.82 years), comprising 35 ALL survivors and a paired comparison group. ALL survivors endured more physical ( M = 1.64, SD = 1.00) and relational bullying ( M = 1.50, SD = 1.04) than their healthy classmates ( M = 0.90, SD = 0.58; M = 0.90, SD = 0.51 respectively), while facing similar verbal bullying levels ( M = 1.71, SD = 0.99 vs. M = 1.38, SD = 0.69). However, survivors reported less cyberbullying ( M = 0.45, SD = 0.36) and severe bullying ( M = 0.41, SD = 0.05) than their healthy classmates ( M = 1.49, SD = 0.48; M = 0.66, SD = 0.53 respectively). Survivors who returned to a different school cohort post‐remission faced higher bullying risks than those who rejoined their original cohort (−0.79 < β < −0.92; p < 0.001). Physical disfigurements following cancer treatment were a risk factor for victimization only among those who returned to their original cohort. Conclusions: The findings highlight the unique challenges faced by childhood leukemia survivors in school reintegration after cancer therapy, emphasizing the significant effect of the school cohort environment on their bullying experiences.

Children with hematological malignancies, are often hospitalized in pediatric intensive care units (PICU) for sepsis with high mortality and re-admission rates. Risk factors for both are inconsistent. We reviewed data of 190 admissions of children with hematological malignancies to PICU for sepsis. Survival rate (SR) was 85%. Mortality risk factors were: non-complete remission (p < 0.01) and status post-stem cell transplantation (p = 0.02), and best predictors were inotropic drugs (p < 0.01), and Pediatric logistic organ dysfunction-2 (p < 0.01) scores. Patients with viremia had the lowest SR (50%, 0.001). One-quarter of the children were re-admitted due to sepsis, and risk factors were: High-risk (HR) hematological malignancy (p < 0.01) and lack of central venous line (CVL) removal (p < 0.01). Sepsis remains a major cause of death in children with hematological malignancies, and re-admissions are common. Our findings support the recommendation of removing CVL during sepsis and highlight those at the highest risk for sepsis to consider individualized anti-infectious prophylaxis.

Most children diagnosed with acute lymphoblastic leukemia (ALL) will achieve remission and be cured of their disease. However, this high cure rate comes at the cost of acute and chronic treatment-related toxicities. In fact, of those who do not survive, a similar number of children die from either ALL itself or the toxicities associated with its treatment. Therapy- related toxicities, whether acute or chronic, can impact treatment efficacy, overall survival (OS), and the patient’s quality of life. This review focused on six major acute toxicities of ALL therapy, venous thromboembolism, osteonecrosis, neurological sequelae, delayed methotrexate (MTX) elimination, asparaginase-associated pancreatitis, and toxicities resulting from the new biological therapies. Most of these severe acute toxicities of ALL treatment can be mitigated through tailored therapy adaptations for individual patients and careful incorporation of immunotherapy. These adaptations will soon become a central component of contemporary pediatric ALL protocols and ultimately improve patients’ OS and wellness.

Background: Children with hemato-oncological diseases or following stem cell transplantation (SCT) are at high risk for life-threatening infections; sepsis in this population constitutes a substantial proportion of pediatric intensive care unit (PICU) admissions. The current pediatric prognostic scoring tools to evaluate illness severity and mortality risk are designed for the general pediatric population and may not be adequate for this vulnerable subpopulation. Methods: Retrospective analysis was performed on all PICU admissions for sepsis in children with hemato-oncological diseases or post-SCT, in a single tertiary pediatric hospital between 2008 and 2021 ( n = 233). We collected and analyzed demographic, clinical, and laboratory data and outcomes for all patients, and evaluated the accuracy of two major prognostic scoring tools, the Pediatric Logistic Organ Dysfunction-2 (PELOD-2) and the Pediatric Risk of Mortality III (PRISM III). Furthermore, we created a new risk-assessment model that contains additional parameters uniquely relevant to this population. Results: The survival rate for the cohort was 83%. The predictive accuracies of PELOD-2 and PRISM III, as determined by the area under the curve (AUC), were 83% and 78%, respectively. Nine new parameters were identified as clinically significant: age, SCT, viral infection, fungal infection, central venous line removal, vasoactive inotropic score, bilirubin level, C-reactive protein level, and prolonged neutropenia. Unique scoring systems were established by the integration of these new parameters into the algorithm; the new systems significantly improved their predictive accuracy to 91% ( p = 0.01) and 89% ( p < 0.001), respectively. Conclusions: The predictive accuracies (AUC) of the PELOD-2 and PRISM III scores are limited in children with hemato-oncological diseases admitted to PICU with sepsis. These results highlight the need to develop a risk-assessment tool adjusted to this special population. Such new scoring should represent their unique characteristics including their degree of immunosuppression and be validated in a large multi-center prospective study.

In this issue of Blood, Hitzler et al1 demonstrate that high-dose cytarabine (HD-AraC) is required for the best likelihood for cure in the majority of children

Summary: Most childhood acute lymphoblastic leukaemia (ALL) protocols include high‐dose steroid therapy. However, the known potential of high‐dose steroids to significantly elevate intraocular pressure (IOP) and lead to glaucomatous optic neuropathy has not been intensively investigated in children with ALL. Moreover, as children with ALL do not routinely undergo IOP measurements, the need for IOP monitoring and therapy is unknown. We prospectively measured IOP in 90 children with newly diagnosed ALL attending a tertiary paediatric haematology/oncology centre, at diagnosis and at the middle and end of induction therapy. Ocular hypertension (IOP > 21 mm Hg) at any time point was documented in 64 children (71%), and the prevalence increased during induction. Thirty‐six children (40%) had elevated IOP at ALL diagnosis before therapy initiation, and stratification to non‐standard ALL was a risk factor. IOP reduction therapy was administered to 13 children (14%); none required surgery. Values normalised in all cases. On multivariate logistic regression analysis, dexamethasone therapy was a significant risk factor for ocular hypertension. High body mass index was an additional risk factor in children with elevated IOP at ALL diagnosis. Routine evaluation of IOP during steroid therapy is very important in children with ALL to ensure early intervention which may prevent permanent ocular damage.

Asparaginase-associated pancreatitis (AAP) frequently affects children treated for acute lymphoblastic leukemia (ALL) causing severe acute and persisting complications. Known risk factors such as asparaginase dosing, older age and single nucleotide polymorphisms (SNPs) have insufficient odds ratios to allow personalized asparaginase therapy. In this study, we explored machine learning strategies for prediction of individual AAP risk. We integrated information on age, sex, and SNPs based on Illumina Omni2.5exome-8 arrays of patients with childhood ALL (N=1564, 244 with AAP 1.0 to 17.9 yo) from 10 international ALL consortia into machine learning models including regression, random forest, AdaBoost and artificial neural networks. A model with only age and sex had area under the receiver operating characteristic curve (ROC-AUC) of 0.62. Inclusion of 6 pancreatitis candidate gene SNPs or 4 validated pancreatitis SNPs boosted ROC-AUC somewhat (0.67) while 30 SNPs, identified through our AAP genome-wide association study cohort, boosted performance (0.80). Most predictive features included rs10273639 (PRSS1-PRSS2), rs10436957 (CTRC), rs13228878 (PRSS1/PRSS2), rs1505495 (GALNTL6), rs4655107 (EPHB2) and age (1 to 7 y). Second AAP following asparaginase re-exposure was predicted with ROC-AUC: 0.65. The machine learning models assist individual-level risk assessment of AAP for future prevention trials, and may legitimize asparaginase re-exposure when AAP risk is predicted to be low.