Uniform approach to risk classification and treatment assignment for children with acute lymphoblastic leukemia

Abnormal Glucose Metabolism and Body Composition Changes in Childhood Acute Lymphoblastic Leukemia Survivors During Their Adolescence

Childhood acute lymphoblastic leukemia survivors (ALL-S) face an increased risk of abnormal glucose metabolism (AGM). This study aimed to assess glucose metabolism in 141 ALL-S. All underwent an oral glucose tolerance test (OGTT) and were classified into AGM and normal glucose tolerance (NGT) groups. Insulin sensitivity and secretion indices were calculated from plasma glucose and serum insulin derived from the OGTT. Fat mass index (FMI) was derived from body composition analysis. Sixty-seven of 141 (48%) ALL-S had AGM. AGM was demonstrated in 33 of 98 nonobese ALL-S. ALL-S with AGM had a greater waist circumference percentile and FMI SD score than those with NGT. In addition, ALL-S with AGM had lower insulin sensitivity (greater homeostasis model assessment of insulin resistance: 2.3 [1.4, 3.3] vs. 1.0 [0.5, 1.4], P <0.001 and lower whole-body insulin sensitivity index: 3.5 [2.3, 4.1] vs. 7.9 [5.3, 10.9], P <0.001) and lower insulin secretion relative to insulin sensitivity (disposition index: 5.8 [4.2, 10.2] vs. 10.0 [6.1, 14.6], P <0.001) than those with NGT. Therefore, ALL-S could develop AGM regardless of their body mass index status. AGM in ALL-S stemmed from both insulin resistance and impaired insulin secretion.

AI-Assisted Detection for Early Screening of Acute Myeloid Leukemia Using Infrared Spectra and Clinical Biochemical Reports of Blood

Early detection and accurate diagnosis of leukemia pose significant challenges due to the disease's complexity and the need for minimally invasive methods. Acute myeloid leukemia (AML) accounts for most cases of adult leukemia, and our goal is to screen out some AML from adults. In this work, we introduce an AI-enhanced system designed to facilitate early screening and diagnosis of AML among adults. Our approach combines the infrared absorption spectra of serum measured with attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), which identifies distinctive molecular signatures in lyophilized serum, together with standard clinical blood biochemical test results. We developed a multi-modality spectral transformer network (MSTNetwork) to generate latent space feature vectors from these datasets. Subsequently, these vectors were assessed using a linear discriminant analysis (LDA) algorithm to estimate the likelihood of acute myeloid leukemia. By analyzing blood samples from leukemia patients and the negative control (including non-leukemia patients and healthy individuals), we achieved rapid and accurate prediction and identification of acute myeloid leukemia among adults. Compared to conventional methods relying solely on either FTIR spectra or biochemical indicators of blood, our multi-modality classification system demonstrated higher accuracy and sensitivity, ultimately achieving an accuracy of 98% and a sensitivity of 98%, improving the sensitivity by 12% (compared with using only biochemical indicators) or over 6% (compared with using only FTIR spectra). Our multi-modality classification system is also very robust as it gave much smaller standard deviations of the accuracy and sensitivity. Beyond improving early detection, this work also contributes to a more sustainable and intelligent healthcare sector.

Treatment of T-cell Leukemia/Lymphoma in Children and Young Adults With the Memorial Sloan Kettering Cancer Center New York IIB Protocol

We described the Memorial Sloan Kettering Cancer Center New York IIB (MSK-NYII) protocol pilot in 1993, for the treatment of acute lymphoblastic leukemia (ALL) in children at high risk of early relapse. We now report MSK-NYII for the treatment of T-ALL/T-lymphoma over a 15-year period. A review of all patient charts identified 63 treated from 1/1/2000-12/31/2015, with a median follow-up of 9.9 years. Further follow-ups were confounded by the COVID pandemic. Remissions (CR) were defined as <5% marrow blast count on Day 28 and resolution of extramedullary disease. Forty-four had T-ALL, and 19 had stage III/IV lymphoblastic lymphoma (T-LL). Median age at diagnosis was 13.6 years (range 0.4 to 23.7). At diagnosis central nervous system (CNS) leukemia was present in 7/63 patients (11%), cranial nerve palsy in 3 (5%), CNS2 [<5cells/µL cerebrospinal fluid with blasts seen on cytospin] in 11 (17%), testicular enlargement in 3 (5%), and mediastinal mass in 45 (71%). On Day 8, 37 T-ALL (86%) were rapid early responders with <25% marrow blasts. 54 patients had an examination, cerebrospinal fluid, and marrow evaluation on day 28. Remission was demonstrated in 53 (98%) after prior marrow and CNS disease. The 19 T-lymphoma patients had no evidence of disease on day 28. Four relapses in marrow were recorded during therapy. Second remissions were able to be achieved. One patient died without having relapsed and is counted as an event in the event-free survival (EFS) analysis. Four patients, including 3 after the second CR transplant, died during follow-up. One unusual case of T-ALL recurred as T-LL of the colon 5.5 years after diagnosis, 3.5 years after therapy discontinuation. Fifteen years after diagnosis 88% (95% CI=78%-98%) survived event-free, and 91% (95% CI=82%-100%) survived. Twenty-five patients received irradiation. Three had RT to the testes, 3 had cranial RT for cranial nerve palsies, and 19 had cranial radiation for either CNS leukemia, CNS2, or for initial white blood cell >100,000/ µL. The MSK-NYIIB protocol, with a 94% 5-year and 88% 15-year EFS, is an effective therapy for the treatment of T-ALL/lymphoma, with similar toxicity to other high-risk regimens.

Progression of brain injuries associated with methotrexate chemotherapy in childhood acute lymphoblastic leukemia

BACKGROUND

Brain bases and progression of methotrexate-associated neurotoxicity and cognitive disturbances remain unknown. We tested whether brain abnormalities worsen in proportion to intrathecal methotrexate(IT-MTX) doses.

METHODS

In this prospective, longitudinal study, we recruited 19 patients with newly diagnosed acute lymphoblastic leukemia 4-to-20 years of age and 20 matched controls. We collected MRI and neuropsychological assessments at a pre-methotrexate baseline and at week 9, week 22, and year 1 during treatment.

RESULTS

Patients had baseline abnormalities in cortical and subcortical gray matter(GM), white matter(WM) volumes and microstructure, regional cerebral blood flow, and neuronal density. Abnormalities of GM, blood flow, and metabolites worsened in direct proportions to IT-MTX doses. WM abnormalities persisted until week 22 but normalized by year 1. Brain injuries were localized to dorsal and ventral attentional and frontoparietal cognitive networks. Patients had cognitive deficits at baseline that persisted at 1-year follow-up.

CONCLUSIONS

Baseline abnormalities are likely a consequence of neuroinflammation and oxidative stress. Baseline abnormalities in WM microstructure and volumes, and blood flow persisted until week 22 but normalized by year 1, likely due to treatment and its effects on reducing inflammation. The cytotoxic effects of IT-MTX, however, likely contributed to continued, progressive cortical thinning and reductions in neuronal density, thereby contributing to enduring cognitive deficits.

IMPACT

Brain abnormalities at a pre-methotrexate baseline likely are due to acute illness. The cytotoxic effects of intrathecal MTX contribute to progressive cortical thinning, reductions in neuronal density, and enduring cognitive deficits. Baseline white matter abnormalities may have normalized via methotrexate treatment and decreasing neuroinflammation. Corticosteroid and leucovorin conferred neuroprotective effects. Our findings suggest that the administration of neuroprotective and anti-inflammatory agents should be considered even earlier than they are currently administered. The neuroprotective effects of leucovorin suggest that strategies may be developed that extend the duration of this intervention or adapt it for use in standard risk patients.

Clonal evolution defines risk stratification for central nervous system leukemia in adult acute lymphoblastic leukemia

It is well established that central nervous system leukemia (CNSL) is an adverse prognostic factor in acute lymphoblastic leukemia (ALL), yet whether prognostic heterogeneity reside in CNSL is less addressed. Therefore, we aimed to develop potential risk classification for CNSL. We retrospectively analyzed a study in PDT-ALL-2016 pediatric-inspired cohort (N = 494). Flow cytometry (FCM) and next-generation sequencing (NGS) were tested on bone marrow (BM) and cerebrospinal fluid (CSF). The 5-year OS of 437 non-CNSL patients was 62.3% and 33.7% in 57 CNSL patients (P < 0.001). 57 CNSL including 16 primary CNS involvement and 41 CNS relapse patients were divided into 3 groups. The 5-year OS was 48.9% in patients with concordant FCM and NGS between BM and CSF, which were defined as non-clonal evolutionary CNSL, a standard-risk subgroup, while the 5-year OS was 30.2% in patients with discordant FCM or NGS between BM and CSF and isolated CNS relapse (P < 0.05), which were defined as clonal evolutionary CNSL, a high-risk subgroup. Furthermore, the mean times of lumbar punctures to achieve complete remission (CR) in CSF was 4.14 in clonal evolutionary CNSL, comparing to 1.62 in non-clonal evolutionary CNSL (P < 0.05). Based on the evidence of clonal evolution, we develop a risk stratification for CNSL for the first time.

Severe steroid-related neuropsychiatric symptoms during paediatric acute lymphoblastic leukaemia therapy-An observational Ponte di Legno Toxicity Working Group Study

Steroids are a mainstay in the treatment of acute lymphoblastic leukaemia (ALL) in children and adolescents; however, their use can cause clinically significant steroid-related neuropsychiatric symptoms (SRNS). As current knowledge on SRNS during ALL treatment is limited, we mapped the phenotypes, occurrence and treatment strategies using a database created by the international Ponte di Legno Neurotoxicity Working Group including data on toxicity in the central nervous system (CNS) in patients treated with frontline ALL protocols between 2000 and 2017. Ninety-four of 1813 patients in the CNS toxicity database (5.2%) experienced clinically significant SRNS with two peaks: one during induction and one during intensification phase. Dexamethasone was implicated in 86% of SRNS episodes. The most common symptoms were psychosis (52%), agitation (44%) and aggression (31%). Pharmacological treatment, mainly antipsychotics and benzodiazepines, was given to 87% of patients while 38% were hospitalised due to their symptoms. Recurrence of symptoms was reported in 29% of patients and two previously healthy patients required ongoing pharmacological treatment at the last follow up. Awareness of SRNS during ALL treatment and recommendation on treatment strategies merit further studies and consensus.

Acute lymphoblastic leukaemia

Acute lymphoblastic leukaemia (ALL) is a haematological malignancy characterized by the uncontrolled proliferation of immature lymphoid cells. Over past decades, significant progress has been made in understanding the biology of ALL, resulting in remarkable improvements in its diagnosis, treatment and monitoring. Since the advent of chemotherapy, ALL has been the platform to test for innovative approaches applicable to cancer in general. For example, the advent of omics medicine has led to a deeper understanding of the molecular and genetic features that underpin ALL. Innovations in genomic profiling techniques have identified specific genetic alterations and mutations that drive ALL, inspiring new therapies. Targeted agents, such as tyrosine kinase inhibitors and immunotherapies, have shown promising results in subgroups of patients while minimizing adverse effects. Furthermore, the development of chimeric antigen receptor T cell therapy represents a breakthrough in ALL treatment, resulting in remarkable responses and potential long-term remissions. Advances are not limited to treatment modalities alone. Measurable residual disease monitoring and ex vivo drug response profiling screening have provided earlier detection of disease relapse and identification of exceptional responders, enabling clinicians to adjust treatment strategies for individual patients. Decades of supportive and prophylactic care have improved the management of treatment-related complications, enhancing the quality of life for patients with ALL.

Gene expression prognostic of early relapse risk in low-risk B-cell acute lymphoblastic leukaemia in children

ETV6::RUNX1 is the most common fusion gene in childhood acute lymphoblastic leukaemia (ALL) and is associated with favorable outcomes, especially in low-risk children. However, as many as 10% of children relapse within 3 years, and such early relapses have poor survival. Identifying children at risk for early relapse is an important challenge. We interrogated data from 87 children with low-risk ETV6::RUNX1-positive B-cell ALL and with available preserved bone marrow samples (discovery cohort). We profiled somatic point mutations in a panel of 559 genes and genome-wide transcriptome and single-nucleotide variants. We found high TIMD4 expression (> 85th-percentile value) at diagnosis was the most important independent prognostic factor of early relapse (hazard ratio [HR] = 5.07 [1.76, 14.62]; p = 0.03). In an independent validation cohort of low-risk ETV6::RUNX1-positive B-cell ALL (N = 68) high TIMD4 expression at diagnosis had an HR = 4.78 [1.07, 21.36] (p = 0.04) for early relapse. In another validation cohort including 78 children with low-risk ETV6::RUNX1-negative B-cell ALL, high TIMD4 expression at diagnosis had an HR = 3.93 [1.31, 11.79] (p = 0.01). Our results suggest high TIMD4 expression at diagnosis in low-risk B-cell ALL in children might be associated with high risk for early relapse.

Missing the mark? Exploratory analysis of the 10-year-old cutoff as an independent marker of high-risk disease in pediatric B-ALL

This single-center, retrospective study evaluated age as a risk factor for relapsed/refractory disease and/or death in 153 children with B-cell acute lymphoblastic leukemia. The study sample included children near the 10-year age cutoff for high-risk disease (6.0-13.9 years at diagnosis) and without other high-risk features (high white cell count, unfavorable cytogenetics). Children 10.0-13.9 years treated per high-risk protocols did not have inferior outcomes compared with children aged 6.0-9.9 years initiating treatment per standard-risk protocols. The study indicates that, in the era of cytogenetics, an age threshold of 10 years might not be an independent prognostic marker. Multicenter analyses are needed.

Biological Markers of High-Risk Childhood Acute Lymphoblastic Leukemia

Childhood acute lymphoblastic leukemia (ALL) has witnessed substantial improvements in prognosis; however, a subset of patients classified as high-risk continues to face higher rates of relapse and increased mortality. While the National Cancer Institute (NCI) criteria have traditionally guided risk stratification based on initial clinical information, recent advances highlight the pivotal role of biological markers in shaping the prognosis of childhood ALL. This review delves into the emerging understanding of high-risk childhood ALL, focusing on molecular, cytogenetic, and immunophenotypic markers. These markers not only contribute to unraveling the underlying mechanisms of the disease, but also shed light on specific clinical patterns that dictate prognosis. The paradigm shift in treatment strategies, exemplified by the success of tyrosine kinase inhibitors in Philadelphia chromosome-positive leukemia, underscores the importance of recognizing and targeting precise risk factors. Through a comprehensive exploration of high-risk childhood ALL characteristics, this review aims to enhance our comprehension of the disease, offering insights into its molecular landscape and clinical intricacies in the hope of contributing to future targeted and tailored therapies.

Fever at Time of Leukemia Diagnosis in Children: Predictor of Bloodstream Infection or Catheter Removal?

PURPOSE

To assess the incidence of fever at diagnosis in children with leukemia and determine if fever at diagnosis is a predictor of bloodstream infection (BSI) or central venous access device (CVAD) removal due to infection either within the first 30 days or between 30 and 90 days after CVAD insertion.

MATERIALS AND METHODS

One hundred fifty-one patients with acute leukemia (July 1, 2018, to December 31, 2020) who underwent a CVAD insertion within 2 weeks of diagnosis were included. Patient data included demographic characteristics, fever at diagnosis, CVAD type, antibiotics before and/or on the day of CVAD insertion, BSI incidence, BSI rates per 1,000 catheter days, and need for catheter removal after CVAD insertion within 30 days and between 30 and 90 days.

RESULTS

Patients with fever at diagnosis had a significantly higher incidence of BSI within the first 30 days after CVAD insertion (17/23) than that among patients without fever (6/23) (P = .046) at diagnosis. No statistically significant difference was observed in the incidence of BSI between 30 and 90 days after CVAD insertion between patients with fever (5/11) and those without fever at diagnosis (6/11) (P = .519). Fever at diagnosis was not a predictor of CVAD removal within 30 days (9 patients required CVAD removal; 7/9 had fever and 2/9 had no fever) (P = .181) or between 30 and 90 days (4 patients required CVAD removal; 1/4 had fever and 3/4 had no fever at diagnosis) (P = .343) after insertion.

CONCLUSIONS

Fever at diagnosis in patients with leukemia is not a predictor of CVAD removal due to infection.

Treatment of Pediatric Acute Lymphoblastic Leukemia: A Historical Perspective

Acute lymphoblastic leukemia (ALL) is the most common disease in pediatric oncology. The history of developmental therapeutics for ALL began in the 1960s with the repetition of "unreliable" medical interventions against this lethal disease. By the 1990s, the development of multi-agent chemotherapy and various types of supportive care rendered ALL treatable. Highly sophisticated, molecular, diagnostic techniques have enabled highly accurate prediction of the relapse risk, and the application of risk-adapted treatments has increased the survival rate in the standard-risk group to nearly 100% in most European nations and North America. Incorporation of state-of-the-art, molecularly targeted agents and novel treatments, including cell and immunotherapy, is further improving outcomes even in the high-risk group. On the other hand, the financial burden of treating children with ALL has increased, imperiling the availability of these diagnostic and treatment strategies to patients in low- and middle-income countries (LMICs). The fundamental treatment strategy, consisting of corticosteroid and classical cytotoxic therapy, has achieved fairly good outcomes and should be feasible in LMICs as well. The present review will discuss the history of developmental therapeutics for childhood ALL in various countries through an extensive literature review with the aim of proposing a model for a treatment backbone for pediatric ALL. The discussion will hopefully benefit LMICs and be useful as a base for future clinical trials of novel treatments.

Transcriptome Sequencing Allows Comprehensive Genomic Characterization of Pediatric B-Acute Lymphoblastic Leukemia in an Academic Clinical Laboratory

Studies have shown the power of transcriptome sequencing [RNA sequencing (RNA-Seq)] in identifying known and novel oncogenic drivers and molecular subtypes of B-acute lymphoblastic leukemia (B-ALL). The current study investigated whether the clinically validated RNA-Seq assay, coupled with a custom analysis pipeline, could be used for a comprehensive B-ALL classification. Following comprehensive clinical testing, RNA-Seq was performed on 76 retrospective B-ALL cases, 28 of which had known and 48 had undetermined subtype. Subtypes were accurately identified in all 28 known cases, and in 38 of 48 unknown cases (79%). The subtypes of the unknown cases included the following: PAX5alt (n = 12), DUX4-rearranged (n = 6), Philadelphia chromosome-like (n = 5), low hyperdiploid (n = 4), ETV6::RUNX1-like (n = 3), MEF2D-rearranged (n = 2), PAX5 P80R (n = 2), ZEB2/CEBP (n = 1), NUTM1-rearranged (n = 1), ZNF384-rearranged (n = 1), and TCF3::PBX1 (n = 1). In 15 of 38 cases (39%), classification based on expression profile was corroborated by detection of subtype-defining oncogenic drivers missed by clinical testing. RNA-Seq analysis also detected large copy number abnormalities, oncogenic hot-spot sequence variants, and intragenic IKZF1 deletions. This pilot study confirms the feasibility of implementing an RNA-Seq workflow for clinical diagnosis of molecular subtypes in pediatric B-ALL, reinforcing that RNA-Seq represents a promising global genomic assay for this heterogeneous leukemia.

Allogeneic hematopoietic stem cell transplantation for pediatric acute lymphoblastic leukemia

This study was aimed to explore the prognosis of allogenic hematopoietic stem cell transplantation (allo-HSCT) in pediatric patients with acute lymphoblastic leukemia (ALL). This retrospective case series study included children with ALL who underwent allo-HSCT at Beijing Children's Hospital of Capital Medical University, Beijing, China, between January 2009 and December 2019. The outcomes included 5-year overall survival (OS) and event-free survival (EFS). A total of 75 children (52 males) were included. The median age at presentation was 5.30 years, and the median time from diagnosis to transplantation was 1.64 years. There were 15 human leukocyte antigen (HLA)-matched and 60 HLA-semi-matched transplants, 73 complete remissions (CR), and 2 MRD-positive transplants. The median follow-up time was 41 months. Out of 75 patients, 51 children survived, and 24 died/given up at the terminal stage. The 5-year OS and EFS rates were 67.77% and 57.30%, respectively, whereas the 5-year recurrence rate was 35.69%. Acute and chronic graft versus host diseases occurred in 40 and 28 cases, respectively. Children with MLL gene fusion had higher survival rates compared to other subgroups. Haplo-HSCT is not inferior to HLA-matched transplant. The children with MLL rearrangement had an acceptable 5-year OS, while complications and relapse should be monitored.

The feasibility of implementing Toronto childhood cancer stage guidelines and estimating the impact on outcome for childhood cancers in seven pediatric oncology units in sub-Saharan Africa. A study from the Franco-African Pediatric Oncology Group

BACKGROUND

The improvement of childhood cancer outcome is determined by early diagnosis, effective treatment, supportive care, and adequate medical follow-up. Stage at diagnosis may reflect timeliness of diagnosis, therefore standardized registration of stage is essential for interpretation of regional differences and time trends in survival. Here, we describe the feasibility of implementing the Toronto Childhood Cancer Stage Guidelines (hereafter Toronto Guidelines [TG]) in the hospital-based cancer registry of the Franco-African Pediatric Oncology Group (GFAOP), and assess the impact of TG stage on outcome in pediatric oncology units (POUs) in seven low- and middle-income countries in sub-Saharan Africa (SSA).

METHODS

All cancer patients diagnosed before 15 years of age with one of the 15 cancer types defined in TG, resident in one of the participating countries, and attending one of the selected POUs in 2017-2019 were included. Stage was assigned according to TG. Patients were followed-up for vital status for at least 12 months post diagnosis. Survival at 3, 6, and 12 months was calculated using Kaplan-Meier method and compared between POUs and tumor groups using log-rank test.

RESULTS

TG stage was assigned to 1772 of 2446 (89%) cases diagnosed with one of 11 cancer types. It was not possible to assign TG stage to acute lymphoblastic leukemia (ALL) and the three types of the central nervous system tumors included in the TG. One-year overall survival (OS) was 58% [95% confidence interval: 55-60] and varied between POUs. Survival declined with increasing stage for four tumor types and was statistically significant for two.

CONCLUSION

Except for ALL and brain tumors, we demonstrated feasibility of TG implementation for childhood solid cancers in participating POUs in SSA, and provided a baseline assessment of childhood cancer outcomes against which future stage distribution and survival can be measured as timelines of diagnosis improve over time within the GFAOP network.

Pediatric acute myeloid leukemia and hyperleukocytosis with WBC count greater than 50 × 109/L

BACKGROUND

Acute myeloid leukemia (AML) and hyperleukocytosis have an unfavorable prognosis, but the impact of hyperleukocytosis on the prognosis of pediatric AML remains uncertain. We investigated the clinical characteristics and prognosis of pediatric AML with hyperleukocytosis, defined as WBC ≥ 50 × 109/L.

METHODS

A total of 132 patients with newly diagnosed childhood AML with hyperleukocytosis were consecutively enrolled at our center from September 2009 to August 2021 to investigate prognostic factors and clinical outcomes.

RESULTS

Hyperleukocytosis occurred in 27.4% of AML patients. Pediatric patients with hyperleukocytosis had similar CR and OS rates to those without hyperleukocytosis, but had a lower EFS rate. In our study, rates of CR1, mortality, relapsed/refractory disease, and HSCT were comparable between AML patients with WBC counts of 50-100 × 109/L and ≥ 100 × 109/L. AML patients with a WBC count of 50-100 × 109/L had a similar 5-year OS rate to patients with a WBC count ≥ 100 × 109/L (74.6% vs. 75.4%, P = 0.921). Among all patients with hyperleukocytosis, the FAB M5 subtype was associated with significantly inferior survival, and the prognosis of CBF-AML was good.

CONCLUSIONS

Pediatric AML patients with hyperleukocytosis have the similar prognosis regardless of whether their WBC count is 50-100 × 109/L or ≥ 100 × 109/L.

Tooth Abnormalities and Their Age-Dependent Occurrence in Leukemia Survivors

The multidrug nature of anticancer treatment and different treatment protocols used in the studies are likely to be a major limitation in establishing real risk factors determining the occurrence of dental abnormalities. The authors aimed to establish a relationship between the duration and the dose of chemotherapy and the number of tooth adverse effects in the group receiving the same treatment. Of the 40 anticancer therapy recipients who attended the outpatient dental clinic, 7 leukemia survivors receiving the treatment according to the ALL IC-BFM 2002 protocol were selected. The study group consisted of four females and three males aged 92 to 207 months at the time of dental examination and 29 to 91 months at leukemia diagnosis. As a result of the clinical and radiological examination, dental abnormalities such as agenesis, tooth size reduction, root abnormalities, and taurodontia were identified, and the medical records of all survivors were reviewed in terms of drugs administered, their doses, and treatment schedules. No correlation was observed between the treatment duration of an intensive therapy, the entire therapy, and the number of tooth abnormalities. No relationship was also found between the number of dental abnormalities and the cumulative dose of vincristine, L-asparaginase, methotrexate, cyclophosphamide, cytarabine, and 6-mercaptopurine. The age at the onset of antineoplastic therapy is likely to be the strongest risk factor for toxic injury during tooth development.

Drivers of Differential Time to Diagnosis in Pediatric ALL Tied to Race and Ethnicity

Acute lymphoblastic leukemia (ALL) is the most common childhood malignancy, with diagnosis preceded by symptoms that may include fever, weight loss, fatigue, bleeding, and bruising. Timely diagnosis and treatment of ALL may lead to improved outcomes and reduced morbidity from associated complications, including tumor lysis syndrome, hyperviscosity, and stroke. We performed a retrospective cohort analysis of 274 pediatric pre-B cell ALL and acute lymphoblastic lymphoma patients within Montefiore Health System to determine whether there were factors associated with time from symptom onset to diagnosis. The median time to diagnosis for all patients was 11.5 days (interquartile range: 7.8, 14.3). Those with Medicaid insurance (n=189) were diagnosed sooner than those with private/self-pay insurance (n=85) (median of 10 vs. 16 days; P =0.05). English and other language speakers experienced fewer median days from symptom onset to diagnosis date compared with Spanish speakers (11 vs. 7 vs. 14; P =0.05). Insurance status may impact the time to diagnosis to a greater degree in non-Hispanic patients, while the English language and female sex may represent a greater advantage to Hispanic patients. Insurance status and language preference may impact the time to diagnosis of pediatric ALL. There is a further need to confirm our findings and to study possible causes driving these disparities.

Weight status in survivors of childhood acute lymphocytic leukemia in South Korea: a retrospective descriptive study

PURPOSE

This study investigated weight status in survivors of childhood acute lymphocytic leukemia (ALL) and identified related factors.

METHODS

A retrospective review of the electronic medical records of survivors of childhood ALL (n=230) was conducted. We analyzed the survivors' characteristics, including sex, age, weight status at diagnosis, central nervous system involvement, risk classification, length of treatment, radiation therapy, and hematopoietic stem cell transplantation. Analysis of variance and the chi-squared test were applied to investigate influencing factors.

RESULTS

The weight status distribution was as follows: 23 individuals (10.0%) were classified as underweight, 151 individuals (65.7%) were healthy weight, and 56 individuals (24.3%) were overweight/obese. Age at diagnosis (F=10.03, p<.001), weight status at diagnosis (x2=43.41, p<.001), and risk classification (F=10.98, p=0.027) showed significant differences among the weight status groups. Survivors who were older at diagnosis and those in the very high-risk category had a higher likelihood of experiencing underweight status during their survivorship, while survivors who were overweight/obese at diagnosis were more likely to remain overweight/obese at the time of survival.

CONCLUSION

Considering the potential health implications related to an unhealthy weight status in survivors of ALL, it is imperative to undertake early identification and implement interventions for at-risk individuals.

Evaluation of factors leading to poor outcomes for pediatric acute lymphoblastic leukemia in Mexico: a multi-institutional report of 2,116 patients

Background and aims

Pediatric acute lymphoblastic leukemia (ALL) survival rates in low- and middle-income countries are lower due to deficiencies in multilevel factors, including access to timely diagnosis, risk-stratified therapy, and comprehensive supportive care. This retrospective study aimed to analyze outcomes for pediatric ALL at 16 centers in Mexico.

Methods

Patients <18 years of age with newly diagnosed B- and T-cell ALL treated between January 2011 and December 2019 were included. Clinical and biological characteristics and their association with outcomes were examined.

Results

Overall, 2,116 patients with a median age of 6.3 years were included. B-cell immunophenotype was identified in 1,889 (89.3%) patients. The median white blood cells at diagnosis were 11.2.5 × 103/mm3. CNS-1 status was reported in 1,810 (85.5%), CNS-2 in 67 (3.2%), and CNS-3 in 61 (2.9%). A total of 1,488 patients (70.4%) were classified as high-risk at diagnosis. However, in 52.5% (991/1,889) of patients with B-cell ALL, the reported risk group did not match the calculated risk group allocation based on National Cancer Institute (NCI) criteria. Fluorescence in situ hybridization (FISH) and PCR tests were performed for 407 (19.2%) and 736 (34.8%) patients, respectively. Minimal residual disease (MRD) during induction was performed in 1,158 patients (54.7%). The median follow-up was 3.7 years. During induction, 191 patients died (9.1%), and 45 patients (2.1%) experienced induction failure. A total of 365 deaths (17.3%) occurred, including 174 deaths after remission. Six percent (176) of patients abandoned treatment. The 5-year event-free survival (EFS) was 58.9% ± 1.7% for B-cell ALL and 47.4% ± 5.9% for T-cell ALL, while the 5-year overall survival (OS) was 67.5% ± 1.6% for B-cell ALL and 54.3% ± 0.6% for T-cell ALL. The 5-year cumulative incidence of central nervous system (CNS) relapse was 5.5% ± 0.6%. For the whole cohort, significantly higher outcomes were seen for patients aged 1-10 years, with DNA index >0.9, with hyperdiploid ALL, and without substantial treatment modifications. In multivariable analyses, age and Day 15 MRD continued to have a significant effect on EFS.

Conclusion

Outcomes in this multi-institutional cohort describe poor outcomes, influenced by incomplete and inconsistent risk stratification, early toxic death, high on-treatment mortality, and high CNS relapse rate. Adopting comprehensive risk-stratification strategies, evidence-informed de-intensification for favorable-risk patients and optimized supportive care could improve outcomes.

Association of the clinical profile and overall survival of pediatric patients with acute lymphoblastic leukemia

Introduction

The clarification of etiopathology, the improvement of chemotherapy regimens and their risk stratifications, and the improvement in treatment support have increased the survival of children and adolescents affected by Acute Lymphoblastic Leukemia (ALL) past few years. This study aimed to estimate overall survival (OS) and event-free survival (EFS) in an onco-hematology treatment center in Brazil, reports the main clinical-laboratory characteristics of patients at diagnosis, verify the frequency of treatment-related adverse effects and the main causes of death.

Material and methods

Retrospective analysis involving patients diagnosed with ALL, treated with the protocol of the Brazilian Group for Treatment of Leukemias in Childhood (GBTLI), between 2010 and 2020 was carried out; the outcomes (relapse, deaths, development of new neoplasms) were analyzed SPSS® software was used for the statistical analyses, and the p-value was considered significant when less than 0.05 for all analyses.

Results

109 patients were included in the study; the median age was 5 years, with a slight predominance of males. Sixty-six patients were classified as high-risk (HR) group and 43 patients were classified as low-risk (LR) group. After 5 years of diagnosis, the OS was 71.5%, and the EFS was 65%. No statistical difference was found between the HR and LR groups for OS and EFS, while leukocyte counts were statistically associated with the outcome of death (p = 0.028). Among the patients, 28 (25.6%) died due to infection accounting 46.4% of death causes. Among the 34 patients with unfavorable outcomes (death and/or relapse), 32 had no research for the minimal residual disease at the end of remission induction, and 25 were not investigated for the presence of chromosomal abnormalities. The most reported complications and treatment-related adverse effects were increased liver transaminases (85.9%), airway infection (79.4%), oral mucositis (67.2%), febrile neutropenia (64.4%), and diarrhea (36.4%).

Conclusions

The rates of OS and EFS obtained in this cohort are similar to those obtained in the few previous similar studies in Brazil and lower than those carried out in developed countries. The unavailability of prognostic tests may have hindered risk stratification and influenced the results obtained.

Reductions in Bone Mineral Density Are Apparent Early in Children With Prevalent Osteonecrosis Lesions Following Leukemia Therapy

Osteonecrosis (ON) is a serious complication of childhood acute lymphoblastic leukemia. We determined the prevalence of osteonecrotic lesions in our patient population by a one-time multisite magnetic resonance imaging (MRI) more than 1 year following leukemia therapy. MRI findings were evaluated in relationship to clinical factors (including longitudinal changes in bone mineral density [BMD]). Eighty-six children enrolled in the Steroid Associated Osteoporosis in the Pediatric Population (STOPP) study were evaluated for ON at 3.1 ± 1.3 years following therapy. Thirty children had a total of 150 confirmed ON lesions (35%). Lumbar spine (LS) BMD Z-scores (mean ± SD) were low at diagnosis and similar between patients with and without ON (-1.09 ± 1.53 versus -1.27 ± 1.25, p = 0.549). LS BMD Z-scores declined from baseline to 12 months in children with ON (-0.31 ± 1.02) but not in those without (0.13 ± 0.82, p = 0.035); the hip BMD Z-scores from baseline to 24 months declined in both groups, but to a greater extent in those with ON (-1.77 ± 1.22) compared to those without (-1.03 ± 1.07, p = 0.045). At the time of the MRI, mean total hip and total body (TB) BMD Z-scores were lower in children with ON (hip -0.98 ± 0.95 versus -0.28 ± 1.06, p = 0.010; TB -1.36 ± 1.10 versus -0.48 ± 1.50, p = 0.018). Pain occurred in 11/30 (37%) with ON versus 20/56 (36%) without, p = 0.841. In multivariable models, older age at diagnosis (odds ratio [OR] 1.57; 95% confidence interval [CI], 1.15-2.13; p = 0.004), and hip BMD Z-score at MRI (OR 2.23; 95% CI, 1.02-4.87; p = 0.046) were independently associated with ON. Overall, one-third of children demonstrated ON after leukemia therapy. Those with ON had greater reductions in spine and hip BMD Z-scores in the first 1 and 2 years of therapy, respectively. Older age and lower hip BMD Z-scores at MRI were significantly associated with prevalent, off-therapy ON. These data assist in identifying children at risk of ON. © 2023 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Novel RUNX1 Variation in B-cell Acute Lymphoblastic Leukemia

Acute lymphoblastic leukemia (ALL) is a malignant disease of hematopoietic stem cells. B cell ALL (B-ALL) is characterized by highly proliferative and poorly differentiated progenitor B cells in the bone marrow. Chromosomal rearrangements, aberrant cell signaling, and mutations lead to dysregulated cell cycle and clonal proliferation of abnormal B cell progenitors. In this study, we aimed to examine hot spot genetic variations in the RUNX1, IDH2, and IL2RA genes in a group of (n=52) pediatric B-ALL. Sanger sequencing results revealed a rare RUNX1 variant p.Leu148Gln in one B-ALL patient with disease recurrence. Additionally, common intronic variations rs12358961 and rs11256369 of IL2RA were determined in two patients. None of the patients had the IDH2 variant. RUNX1, IDH2, and IL2RA variations were rare events in ALL. This study detected a novel pathogenic RUNX1 variation in a patient with a poor prognosis. Examining prognostically important genetic anomalies of childhood lymphoblastic leukemia patients and the signaling pathway components will pilot more accurate prognosis estimations.

Hyperleukocytosis in Childhood Acute Leukemia: Early Complications and Survival Outcomes

Hyperleukocytosis and extreme hyperleukocytosis, defined as initial white blood cell counts greater than 100 × 10⁹/L and 200 × 10⁹/L, respectively, have been associated with unfavorable outcomes. This study aimed to determine the early complications and survival outcomes of childhood leukemia patients with hyperleukocytosis. The medical records of 690 children newly diagnosed with acute leukemia between January 1998 and December 2017 were retrospectively reviewed. The Kaplan-Meier method and log-rank test were used to assess and compare the survival outcomes. Multivariate Cox proportional hazards regression was used to determine associated risk factors for overall survival. We found that 16.6% of 483 childhood acute lymphoblastic leukemia (ALL) patients and 20.3% of 207 childhood acute myeloid leukemia (AML) patients had hyperleukocytosis at diagnosis. ALL patients with hyperleukocytosis had more early complications than those without hyperleukocytosis (p < 0.05). Among the ALL group, the 5-year overall survival rate for those with hyperleukocytosis was significantly lower than for those without hyperleukocytosis (37.2% vs. 67.8%, p < 0.0001), while the difference was not statistically significant in the AML group (19.0% vs. 30.2%, respectively, p = 0.26). Hyperleukocytosis (hazard ratio [HR]: 2.04), extreme hyperleukocytosis (HR: 2.71), age less than 1 year (HR: 3.05), age greater than 10 years (HR: 1.64), and male sex (HR: 1.37) were independently associated with poorer overall survival in childhood ALL patients. Extreme hyperleukocytosis (HR: 2.63) and age less than 1 year (HR: 1.82) were independently associated with poorer overall survival in AML patients. Hyperleukocytosis was associated with adverse survival outcomes in childhood leukemia.

What is Next in Pediatric B-cell Precursor Acute Lymphoblastic Leukemia

Cure rates now exceed 90% in many contemporary trials for children with B-cell acute lymphoblastic leukemia (ALL). However, treatment remains suboptimal and therapy is toxic for all patients. New treatment options potentially offer the chance to reduce both treatment resistance and toxicity. Here, we review recent advances in ALL diagnostics, chemotherapy, and immunotherapy. In addition to describing recently published results, we also attempt to project the impact of these new developments into the future to imagine what B-ALL therapy may look like in the next few years.

Impact of Age on Overall Survival Among Children With Wilms Tumor: A Population-based Registry Analysis

OBJECTIVES

International trials have reported conflicting findings on whether the association between age and worse overall survival (OS) among children with Wilms tumor (WT) is due to age as an independent prognostic factor or the observation of more advanced disease at older ages. We sought to further elucidate this relationship using a population-based registry analysis.

METHODS

The Surveillance, Epidemiology, and End Results database was queried for all patients diagnosed with WT under the age of 20. The association between age and OS was assessed using multivariable Cox proportional hazards regression.

RESULTS

In this study, 3463 patients (54% female) were diagnosed with WT between 1975 and 2016. More advanced stage, larger primary tumor size, lymph node involvement, disease requiring radiotherapy, and omission of surgery were associated with worse OS ( P <0.05). More advanced stage, larger primary tumor size, and disease requiring radiotherapy were also associated with older age, whereas bilateral disease was associated with younger age ( P <0.001). On average, each year of age conferred an incremental hazard ratio (HR) of 1.07 (95% CI, 1.01 to 1.12, P =0.018) independent of relevant covariates. The rise in adjusted OS HR was most pronounced after the transitions in diagnosis age from 2 to 3 (HR age 3-15 vs. 0-2 1.77, 95% CI, 1.11 to 2.82, P =0.016) and from 15 to 16 (HR age 16-19 vs. 3-15 2.58, 95% CI, 1.06 to 6.25, P =0.036).

CONCLUSIONS

Diagnosis of pediatric WT at an older age was found to be independently associated with worse OS. Although additional prospective studies are warranted to examine tumor biology and other potential correlates, more aggressive treatment of older children based on age, especially as they approach early adulthood, may be considered in the multidisciplinary management of WT.

Outcomes following induction failure in Japanese children with acute lymphoblastic leukemia

The characteristics and prognosis of Japanese children with acute lymphoblastic leukemia (ALL) who fail to achieve complete remission after remission induction chemotherapy (i.e., experience induction failure) are poorly understood. Therefore, we retrospectively analyzed data of patients enrolled in Japanese clinical trials for newly diagnosed ALL between 1996 and 2009. Among 4956 participants, 89 (1.8%) experienced induction failure. With a 6.0-year median follow-up, the 5-year overall survival rate of the entire cohort was 43.0% ± 5.5%. Survival rates did not differ between patients with B-cell precursor ALL (BCP-ALL) and T-cell ALL (T-ALL). In multivariate analysis, day 15 M3 marrow (bone marrow blast count ≥ 25%) was significantly correlated with poorer survival in the whole or BCP-ALL cohorts. In T-ALL, age < 6 years was significantly associated with poor survival. However, due to the small sample size, this correlation must be further investigated. Most T-ALL and BCR-ABL-positive BCP-ALL patients underwent allogeneic stem cell transplantation (allo-SCT). Survival rates did not differ between BCR-ABL-negative BCP-ALL patients who did and did not undergo allo-SCT, possibly due to the inclusion of lower-risk patients in the latter group. In conclusion, the induction failure rate and survival after diagnosis of induction failure in our study were comparable to previously reported figures.

Impact of minimal residual disease on relapse in childhood acute lymphoblastic leukemia: Lessons learnt from a tertiary cancer center in India

Prognostic predictive value of end of induction minimal residual disease (EOI-MRD) is well established in acute lymphoblastic leukemia (ALL). We evaluated the factors likely to affect EOI-MRD positivity (>0.01%) by flow cytometry and relapse in different BFM-95 (Berlin-Frankfurt-Munich) risk groups among children and adolescents. In this retrospective study, data of 223 newly diagnosed patients with ALL was analyzed. Association between demographic and pretreatment characteristics with EOI-MRD was assessed. Risk factors for relapse were analyzed using univariate and multivariate Cox regression. Proportion of the SR (standard risk), MR (moderate risk), and HR (high risk) patients was 18.8%, 60.9%, 20.3%, respectively. Positive EOI-MRD among these risk groups was observed in 11.9%, 18.3%, and 55.5% patients respectively (p value <.01%). MRD positivity was more likely to be associated with older age (>10 years) and BFM-HR patients (p value .0008 and <.0001). Thirty-four (15.2%) patients relapsed in the whole cohort. On univariate analysis, statistically significant factors for RFS (relapse-free survival) included hyperleukocytosis, high-risk cytogenetics, NCI (National Cancer Institute) high risk, poor day-8 prednisolone response, BFM-HR and positive EOI-MRD status. Of all these only EOI-MRD retained its impact by multivariate analysis. Positive EOI-MRD significantly predicted relapse in BFM-MR with 5-year RFS of 88.0% and 68.4% (p value .02). Five-year RFS of EOI-MRD negative and positive groups were 86.4% and 65.5%, respectively (p value .004). EOI-MRD is a powerful tool to predict relapse in children and adolescent with ALL especially in BFM-MR. Application of MRD in HR patients needs to be redefined in conjunction with other variables.

The Impact of COVID-19 on Pediatric Malignancy Diagnosis and Treatment: Never the Same but Lessons Learned

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic affected the pediatric oncology population globally. Over the course of 2 years, increasing reports have been made to better understand this entity and its pathologic complications on these patients. The pandemic has allowed healthcare providers, hospital systems, and leading oncologic societies to quickly adapt and formulate new guidelines for the effective understanding, management, and treatment of patients with pediatric malignancy.

The prognostic significance of cytokine receptor-like factor 2 expression and <i>JAK2</i> mutation in pediatric B-cell acute lymphoblastic leukemia: A prospective cohort study

Acute lymphoblastic leukemia (ALL) is the most common pediatric malignancy. Philadelphia (Ph)-like B-cell acute lymphoblastic leukemia (B-ALL) is defined by a gene expression profile similar to Phpositive B-ALL and shows a large number of genetic alterations in the cytokine receptor and kinasesignaling pathway genes that contribute to its aggressive phenotype and frequent disease recurrence – the main cause of death in affected children. Here, we aimed to correlate CRLF2 expression and JAK2 mutations in B-ALL patients with other prognostic factors and the patients’ outcomes as well as to evaluate their prognostic significance. The study was approved by the local institutional review board and written consents were obtained from a parent of each child before their enrolment. We included 54 newly diagnosed B-ALL pediatric patients (median age: 9.0 (2.0–18.0)) who were stratified either into a standard-risk (SR) or high-risk (HR) group and treated according to the modified BerlinFrankfurt-Münster 90 protocol (ALL-BFM 90). Fresh bone marrow samples were used to determine CRLF2 expression as well as to search for the JAK2 V617F mutation. Normal CRLF2 expression was reported in the SR patients much more often than in the HR group, while its overexpression was more common in the HR patients than in the SR ones (22 vs 6 and 18 vs 8, respectively, p < 0.001). CRLF2 was also more often overexpressed in the MRD-positive cases than in the negative ones (17 vs 9, p < 0.001), while normal CRLF2 expression was more common in the MRD-negative patients compared to the MRD-positive ones (24 vs 4, p < 0.001) which supports the unfavorable prognostic value of CRLF2 in relation to MRD positivity at the end of the induction treatment. JAK2 mutation was detected only in 2 patients belonging to the CRLF2 overexpression group which made the assessment of the prognostic significance of this mutation impossible. Notably, none of the patients with normal CRLF2 expression ended up relapsing while 4 patients with overexpressed CRLF2 developed a relapse (p = 0.031). The study subjects were followed up for up to 24 months, and we did not find CRLF2 overexpression to negatively influence overall survival, however, it did have an adverse effect on relapse-free survival. In summary, CRLF2 overexpression was found to be an unfavorable prognostic factor in childhood ALL as it was expressed more in high-risk patients and in those with poor treatment response. The analysis of CRLF2 expression in B-ALL pediatric patients may help in risk stratification and can potentially offer new treatment options based on novel CRLF2 inhibitors.

Characterisation of children and adolescents with acute lymphoblastic leukaemia who presented without peripheral blood blasts at diagnosis

Of 1003 children with acute lymphoblastic leukaemia (ALL), 147 (14.7%) presented without peripheral blood blasts (PBB). While absence of PBB was not independently associated with survival outcomes when compared to those with PBB, patients without PBB had distinct genetic and clinical characteristics. Notably, we identified a novel genotype-phenotype relationship, in that the patients without PBB had a significantly higher incidence of hyperdiploid B-ALL, accounting for almost half of all patients without PBB (46.9% vs. 22.7%, p < 0.001). Further, absence of PBB was associated with decreased rates of leukaemia involvement of the central nervous system (p < 0.001).

Prevalence and risk factors of disseminated intravascular coagulation in childhood acute lymphoblastic leukemia

BACKGROUND

Few studies have examined disseminated intravascular coagulation (DIC) in childhood acute lymphoblastic leukemia (ALL). Our aims were to evaluate the prevalence, risk factors and outcomes of DIC at ALL presentation and during induction chemotherapy.

METHODS

The medical records of ALL patients aged <15 years were retrospectively reviewed. Logistic regression analysis was used to identify risk factors. The Kaplan-Meier method was used to depict survival.

RESULTS

Of the 312 patients, 48 (15.4%) and 76 (24.4%) had DIC at presentation and during induction chemotherapy, respectively. Risk factors for DIC at presentation (OR and 95% CI) were antibiotics prior to admission 2.34 (1.17-4.89), white blood cell count ≥100 × 10⁹/L 2.39 (1.04-5.72), platelets <100 × 10⁹/L 5.44 (1.84-23.4) and high National Cancer Institute (NCI) risk 2.68 (1.08-6.62). Risk factors for DIC during induction chemotherapy were antibiotics prior to admission 1.86 (1.07-3.27), high peripheral blasts 1.01 (1.00-1.02) and transaminitis 2.02 (1.18-3.48). Five-year overall survival of patients who had DIC was significantly lower than those who did not (45.0% vs. 74.1%, p <0.001).

CONCLUSION

Antibiotics prior to admission, hyperleukocytosis, thrombocytopenia and high NCI risk were risk factors of DIC at presentation. Antibiotics prior to admission, high peripheral blasts and transaminitis were risk factors of DIC during induction chemotherapy.

IMPACT

There are only two studies, both published before 2000, evaluating risk factors of DIC in pediatric ALL patients without reporting outcomes. DIC was associated with lower remission and survival rates in pediatric ALL patients. We identified the risk factors of DIC at presentation as antibiotics prior to admission, hyperleukocytosis, thrombocytopenia and high NCI risk. The risk factors of DIC during induction chemotherapy were antibiotics prior to admission, high peripheral blasts and aspartate transaminitis. Pediatric ALL patients who have the aforementioned risk factors should be closely monitored for DIC secondary to infection, and early treatment with appropriate antimicrobial agents is recommended.

Impact of Delay Prior to Treatment in Ethiopian Children with Acute Lymphoblastic Leukemia

Introduction

More than 85% of childhood malignancies occur in developing countries with less than a 30% cure rate as opposed to more than 80% cure rate in developed countries. This disproportionately significant difference might be due to delays in diagnosis, treatment initiation, lack of adequate supportive care, and treatment abandonment. We aimed to determine the impact of overall treatment delay on induction mortality of children with acute lymphoblastic leukemia treated at Tikur Anbessa specialized hospital (TASH).

Methods

A cross-sectional study was conducted among children who were treated from 2016 to 2019. Children with Down syndrome and relapsed leukemia were excluded from this study.

Results

A total of 166 children were included; most patients were males (71.7%). The mean age at diagnosis was 5.9 years. The median time interval from the onset of symptoms to the first TASH visit was 30 days and the median period from TASH's first clinic visit to diagnosis was 11 days. The median time to initiate chemotherapy after diagnosis was 8 days. The total median time from the first onset of symptoms to chemotherapy initiation was 53.5 days. Induction mortality was 31.3%. High-risk ALL and patients with an overall delay between 30 and 90 days were more likely to experience induction mortality.

Discussion

Patient and healthcare system delay is high compared to most studies done and a significant association has been noted with induction mortality. Efforts to expand the pediatric oncology service in the country and efficient diagnostic and treatment approach need to be established to reduce mortality associated with overall delay.

ITPA Polymorphisms and the Incidence of Toxicities in Children with Acute Lymphoblastic Leukemia

Background

6-Mercaptopurine (6-MP), a thiopurine agent, is a essential medication for treating pediatric acute lymphoblastic leukemia (ALL). However, its side effects of neutropenia and hepatotoxicity might interrupt treatment, resulting in poor outcomes. Inosine triphosphate pyrophosphatase (ITPA), an enzyme in the thiopurine pathway, may prevent the accumulation of toxic thiopurine metabolites. Studies on ITPA and thiopurine-associated toxicities are scarce.

Methods

This study retrospectively investigated 1- to 15-year-old children with ALL who received 6-MP during the maintenance phase of treatment between 2000 and 2020. Toxicity during the first year of maintenance therapy and the mean dose of 6-MP were analyzed.

Results

The 209 patients had a median age of 4.8 (0.3-14.8) years. Of these, 124 patients (59.3%) had wild-type ITPA, 73 patients (34.9%) had heterozygous ITPA 94C>A (hetITPA), and 12 patients (5.7%) had homozygous ITPA 94C>A (homITPA), with an allele frequency of 0.23. The incidence of neutropenia among ITPA polymorphisms did not significantly differ (P = 0.813). In patients harboring homITPA, transaminitis was more frequent than other polymorphisms but without a significant difference (P = 0.063). The mean dose of 6-MP for patients with homITPA was significantly lower than that for patients with hetITPA or wild-type ITPA (P = 0.016).

Conclusions

HomITPA had a higher incidence of transaminitis and required a significantly larger dose reduction of 6-MP than wild-type ITPA. Further study is warranted to elucidate the effects of ITPA polymorphisms on toxicity in patients with ALL treated with 6-MP.

Minimal residual disease in BCR::ABL1-positive acute lymphoblastic leukemia: different significance in typical ALL and in CML-like disease

Recently, we defined "CML-like" subtype of BCR::ABL1-positive acute lymphoblastic leukemia (ALL), resembling lymphoid blast crisis of chronic myeloid leukemia (CML). Here we retrospectively analyzed prognostic relevance of minimal residual disease (MRD) and other features in 147 children with BCR::ABL1-positive ALL (diagnosed I/2000-IV/2021, treated according to EsPhALL (n = 133) or other (n = 14) protocols), using DNA-based monitoring of BCR::ABL1 genomic breakpoint and clonal immunoglobulin/T-cell receptor gene rearrangements. Although overall prognosis of CML-like (n = 48) and typical ALL (n = 99) was similar (5-year-EFS 60% and 49%, respectively; 5-year-OS 75% and 73%, respectively), typical ALL presented more relapses while CML-like patients more often died in the first remission. Prognostic role of MRD was significant in the typical ALL (p = 0.0005 in multivariate analysis for EFS). In contrast, in CML-like patients MRD was not significant (p values > 0.2) and inapplicable for therapy adjustment. Moreover, in the typical ALL, risk-prediction could be further improved by considering initial hyperleukocytosis. Early distinguishing typical BCR::ABL1-positive ALL and CML-like patients is essential to enable optimal treatment approach in upcoming protocols. For the typical ALL, tyrosine-kinase inhibitors and concurrent chemotherapy with risk-directed intensity should be recommended; in the CML-like disease, no relevant prognostic feature applicable for therapy tailoring was found so far.

Specific lncRNA signatures discriminate childhood acute leukaemias: a pilot study

BACKGROUND

Long non-coding RNAs are RNAs longer than 200 bps that do not encode any proteins and are able to alter gene expression by acting on different steps of regulation, including DNA methylation and chromatin structure. They represent a class of biomarkers of crescent interest in the hematologic and oncologic fields. Recent studies showed that the expression levels of specific lncRNAs correlate with the prognosis of paediatric patients with Acute Lymphoblastic Leukaemia.

METHODS

We used NGS approaches to analyse the transcriptome of 9 childhood B-ALL patients and 6 childhood T-ALL patients, in comparison with B and T healthy lymphocytes from cord blood. We validate our findings both ex vivo, in a different cohort of 10 B-ALL and 10 T-ALL patients, and in silico using public datasets.

RESULTS

We characterised the lncRNA landscape for B-ALL, T-ALL, healthy B, and T cell progenitors. From the characterised signature, we selected candidate lncRNAs able to discriminate not only B-ALL and T-ALL from healthy subjects but also between the two types of leukaemia, and subsequently validated their potential as a diagnostic tool in an additional cohort of paediatric patients. We confirmed our finding with open access transcriptomic data, comparing ALL lncRNAs with AML lncRNA landscape as well. Finally, expression correlation analyses of T-ALL selected lncRNA biomarkers suggested a possible role in lymphocyte activation and the β-catenin signalling pathway for AC247036.1 and involvement in hedgehog signalling for HHIP-AS1.

CONCLUSIONS

Our work identified a lncRNA signature discriminating paediatric B-ALL and T-ALL from healthy subjects, between them and from AML. This study provides the keystone to future clinical studies determining the theragnostic value of the characterised long non coding transcriptome panorama in a clinical setting for childhood patient management.

Clinical implication of minimal residual disease assessment by next-generation sequencing-based immunoglobulin clonality assay in pediatric B-acute lymphoblastic leukemia

Measuring minimal residual disease (MRD) during treatment is valuable to identify acute lymphoblastic leukemia (ALL) patients who require intensified treatment to avert relapse. We performed the next-generation sequencing (NGS)-based immunoglobulin gene (Ig) clonality assay and evaluated its clinical implication in pediatric B-ALL patients to assess MRD. Fifty-five patients who were diagnosed and treated with de novo (n = 44) or relapsed/refractory B-ALL (n = 11) were enrolled. MRD assessment was performed using the LymphoTrack^® Dx IGH and IGK assay panels. The percentage of the clonal sequences per total read count was calculated as MRD (% of B cells). The data were normalized as the proportion of total nucleated cells (TNC) by LymphoQuant™ Internal control or the B-cell proportion in each sample estimated by flow cytometry or immunohistochemistry. Clonal Ig rearrangement was identified in all patients. The normalized MRD value was significantly lower than the unnormalized MRD value (p < 0.001). When categorizing patients, 27 of 50 patients (54%) achieved normalized MRD <0.01%, while 6 of them did not achieve MRD <0.01% when applying the unnormalized value. The normalized post-induction MRD value of 0.01% proved to be a significant threshold value for both 3-year event-free survival (100% for MRD <0.01% vs. 60.9% ± 10.2% for MRD ≥0.01%, p = 0.007) and 3-year overall survival (100% for MRD <0.01% vs. 78.3% ± 8.6% for MRD ≥0.01%, p = 0.011). However, unnormalized MRD was not a significant factor for outcome in this cohort. Our study demonstrated that MRD assessment by NGS-based Ig clonality assay could be applied in most pediatric B-ALL patients. Normalized post-induction MRD <0.01% was a significant prognostic indicator.

Genetic variation in FOXP3 and ROR-γ genes in pediatric acute lymphocytic leukemia (ALL) patients: correlation with associated cytokines

BACKGROUND

FOXP3 and ROR-γ genes are master regulators of the Treg and Th17 differentiation, respectively. This work was planned to investigate the impact of FOXP3 (rs3761548C/A and rs3761549C/T) and ROR-γ (rs9017A/G & rs9826A/G) gene polymorphism on the vulnerability of pediatric Egyptians to acute lymphoblastic leukemia (ALL). Furthermore, we evaluated the impact of these genetic variations on Treg/Th17-related cytokines.

METHODS

FOXP3 SNPs were genotyped using PCR-based restriction fragment length polymorphism (PCR-RFLP), while ROR-γ SNPs polymorphism were performed by PCR-sequence-specific primer (PCR-SSP). An Enzyme-linked immunosorbent assay (ELISA) was used to assess the levels of Treg/Th17 associated cytokines on 128 ALL children and 124 healthy donors.

RESULTS

Compared to controls, patients had a significant increase (p < 0.01/p < 0.05) in FOXP3rs3761548CC genotype and a significant decrease (p < 0.001/p < 0.01) inrs3761548CA genotype. A significant elevation (p < 0.001/p < 0.01) in ROR-γ rs9017AA genotype and a significant reduction (p < 0.01/p < 0.05) in rs9017AG genotype were detected in ALL patients versus controls. An insignificant change in FOXP3 (rs3761549C/T) and ROR-γ (rs9826A/G) genotypes was demonstrated between both groups. ROR-γ GG and GA haplotypes were significantly decreased (p < 0.05/p < 0.05; p < 0.05/p < 0.05) in ALL subjects compared to healthy ones. Relapsed patients had a significantly higher (p < 0.05/P < 0.05) frequency of FOXP3 rs3761548CA genotype than non-relapsed subjects. ROR-γ rs9017AG and rs9826GG genotypes might be associated with the increase in IL-23 plasma level.

CONCLUSIONS

Our preliminary data provided evidence for the impact ofFOXP3 (rs3761548C/A) and ROR-γ (rs9017A/G) gene polymorphisms and the occurrence of ALL in Egyptian children. Another large-scale prospective study should be conducted to validate these findings.

Characteristics of white blood cell count in acute lymphoblastic leukemia: A COST LEGEND phenotype-genotype study

BACKGROUND

White blood cell count (WBC) as a measure of extramedullary leukemic cell survival is a well-known prognostic factor in acute lymphoblastic leukemia (ALL), but its biology, including impact of host genome variants, is poorly understood.

METHODS

We included patients treated with the Nordic Society of Paediatric Haematology and Oncology (NOPHO) ALL-2008 protocol (N = 2347, 72% were genotyped by Illumina Omni2.5exome-8-Bead chip) aged 1-45 years, diagnosed with B-cell precursor (BCP-) or T-cell ALL (T-ALL) to investigate the variation in WBC. Spline functions of WBC were fitted correcting for association with age across ALL subgroups of immunophenotypes and karyotypes. The residuals between spline WBC and actual WBC were used to identify WBC-associated germline genetic variants in a genome-wide association study (GWAS) while adjusting for age and ALL subtype associations.

RESULTS

We observed an overall inverse correlation between age and WBC, which was stronger for the selected patient subgroups of immunophenotype and karyotypes (ρ_BCP-ALL  = -.17, ρ_T-ALL  = -.19; p < 3 × 10^-4 ). Spline functions fitted to age, immunophenotype, and karyotype explained WBC variation better than age alone (ρ = .43, p << 2 × 10^-6 ). However, when the spline-adjusted WBC residuals were used as phenotype, no GWAS significant associations were found. Based on available annotation, the top 50 genetic variants suggested effects on signal transduction, translation initiation, cell development, and proliferation.

CONCLUSION

These results indicate that host genome variants do not strongly influence WBC across ALL subsets, and future studies of why some patients are more prone to hyperleukocytosis should be performed within specific ALL subsets that apply more complex analyses to capture potential germline variant interactions and impact on WBC.

Low Prevalence of ETV6::RUNX1 Fusion Gene in a Hispanic Population

ETV6::RUNX1 is a genetic rearrangement of good prognosis in children with acute lymphoblastic leukemia (ALL). In Mexico, its prevalence is low in comparison with Caucasian populations. We developed a novel TaqMan one-step RT-qPCR approach to assess the prevalence of four genetic rearrangements in a cohort of Hispanic children with ALL from Mexico City. The prevalence of common fusion gene transcripts was as follows: TCF3::PBX1 7.7%; BCR::ABL1p 190 3.3%; and KMT2A::AFF1 2.8%, and ETV6::RUNX1was observed with low prevalence (10.5%) in comparison to that reported for developed countries. This is consistent with previous findings on Mexican children with ALL and similar to those reported on children from Hispanic populations. The confirmation of a low prevalence of ETV6::RUNX1 in children of a Hispanic origin represents an advancement in the description of genetic factors of ALL in these populations.

Musculoskeletal involvement in childhood leukemia: Characteristics and survival outcomes

BACKGROUND : Childhood leukemia with musculoskeletal (MSK) involvement mimics various conditions, which consequently leads to diagnostic delays. The clinical implication of MSK involvement in this disease on survival outcomes is inconclusive. This study aimed to compare characteristics and survival outcomes between MSK and non-MSK involvement in childhood leukemia.

METHODS

The medical records of children newly diagnosed with acute leukemia of an age under 15 years were retrospectively reviewed. Two-to-one nearest-neighbor propensity score-matching was performed to obtain matched groups with and without MSK involvement. The Kaplan-Meier method and log-rank test were then used to assess the effect of MSK involvement on survival outcomes.

RESULTS

Of 1042 childhood leukemia cases, 81 (7.8%) children had MSK involvement at initial presentation. MSK involvement was more likely in children with acute lymphoblastic leukemia than acute myeloid leukemia (p < 0.05). Hematologic abnormalities were less frequent in the MSK involvement group (p < 0.05). The absence of peripheral blast cells was significantly higher in the MSK involvement group (17.3% vs 9.6%, p = 0.04). Normal complete blood counts with absence of peripheral blast cells were found 2.5% of the children with MSK involvement. By propensity score-matching for comparable risk groups of children with and without MSK involvement, the 5-year overall survival was not significantly different (48.2% vs 57.4%, respectively, p = 0.22), nor was event-free survival (43.3% vs 51.8%, respectively, p = 0.31).

CONCLUSION

Childhood leukemia with MSK involvement had the characteristics of minimal or absent hematologic abnormalities and peripheral blast counts.

Remission, treatment failure, and relapse in pediatric ALL: an international consensus of the Ponte-di-Legno Consortium

Comparison of treatment strategies in de novo pediatric acute lymphoblastic leukemia (ALL) requires standardized measures of efficacy. Key parameters that define disease-related events, including complete remission (CR), treatment failure (TF; not achieving CR), and relapse (loss of CR) require an updated consensus incorporating modern diagnostics. We collected the definitions of CR, TF, and relapse from recent and current pediatric clinical trials for the treatment of ALL, including the key components of response evaluation (timing, anatomic sites, detection methods, and thresholds) and found significant heterogeneity, most notably in the definition of TF. Representatives of the major international ALL clinical trial groups convened to establish consensus definitions. CR should be defined at a time point no earlier than at the end of induction and should include the reduction of blasts below a specific threshold in bone marrow and extramedullary sites, incorporating minimal residual disease (MRD) techniques for marrow evaluations. TF should be defined as failure to achieve CR by a prespecified time point in therapy. Relapse can only be defined in patients who have achieved CR and must include a specific threshold of leukemic cells in the bone marrow confirmed by MRD, the detection of central nervous system leukemia, or documentation of extramedullary disease. Definitions of TF and relapse should harmonize with eligibility criteria for clinical trials in relapsed/refractory ALL. These consensus definitions will enhance the ability to compare outcomes across pediatric ALL trials and facilitate development of future international collaborative trials.

On the Reliability of CNNs in Clinical Practice: A Computer-Aided Diagnosis System Case Study

Leukocytes classification is essential to assess their number and status since they are the body’s first defence against infection and disease. Automation of the process can reduce the laborious manual process of review and diagnosis by operators and has been the subject of study for at least two decades. Most computer-aided systems exploit convolutional neural networks for classification purposes without any intermediate step to produce an accurate classification. This work explores the current limitations of deep learning-based methods applied to medical blood smear data. In particular, we consider leukocyte analysis oriented towards leukaemia prediction as a case study. In particular, we aim to demonstrate that a single classification step can undoubtedly lead to incorrect predictions or, worse, to correct predictions obtained with wrong indicators provided by the images. By generating new synthetic leukocyte data, it is possible to demonstrate that the inclusion of a fine-grained method, such as detection or segmentation, before classification is essential to allow the network to understand the adequate information on individual white blood cells correctly. The effectiveness of this study is thoroughly analysed and quantified through a series of experiments on a public data set of blood smears taken under a microscope. Experimental results show that residual networks perform statistically better in this scenario, even though they make correct predictions with incorrect information.

Temporal changes in incidence of relapse and outcome after relapse of childhood acute lymphoblastic leukemia over three decades; a Nordic population-based cohort study

Relapse remains the main obstacle to curing childhood acute lymphoblastic leukemia (ALL). The aims of this study were to compare incidence of relapse, prognostic factors, and survival after relapse between three consecutive Nordic Society of Pediatric Hematology and Oncology trials. Relapse occurred as a primary event in 638 of 4 458 children (1.0-14.9 years) diagnosed with Ph-negative ALL between 1992 and 2018. The 5-year cumulative incidence of relapse was 17.3% (95% CI 15.4-19.2%) and 16.5% (95% CI 14.3-18.8%) for patients in the ALL1992 and ALL2000 trials, respectively, but decreased to 8.4% (95% CI 7.0-10.1%) for patients in the ALL2008 trial. No changes in duration of first complete remission and site of relapse were observed over time; however, high hyperdiploidy, and t(12;21) decreased in the ALL2008 trial. The 4-year overall survival after relapse was 56.6% (95% CI 52.5-60.5%) and no statistically significant temporal improvements were observed. Age ≥10 years, T-cell immunophenotype, bone-marrow involvement, early and very early relapse, hypodiploidy, and Down syndrome all independently predicted worse outcome after relapse. Improvements in the primary treatment of childhood ALL has resulted in fewer relapses. However, failure to improve outcome of remaining relapses suggests a selection of harder-to-cure relapses and calls for new therapeutic strategies.