Chemotherapy-only treatment effects on long-term neurocognitive functioning in childhood ALL survivors: a review and meta-analysis

Identifying fine motor difficulties in children with acute lymphoblastic leukemia: a scoping review

PURPOSE

Survival rates for children diagnosed with acute lymphoblastic leukemia (ALL) have increased significantly over recent decades, and thus attention shifted toward understanding the adverse effects of cancer treatment. Chemotherapy has side effects that could affect muscle state and diminish motor performance. This scoping review was conducted to map the breadth of evidence for different tools used in fine motor skills assessment, the extent of upper extremity strength, and fine motor performance, highlighting the potential risk factors that may influence these skills.

METHODS

In March 2023, full-text studies that examined fine motor performance and/or upper extremity strength were identified via searches in PubMed, Science Direct, Scopus, Web of Science, and PEDro databases. The titles and abstracts of selected studies were screened according to the inclusion and exclusion criteria.

RESULTS

The search yielded initial 418 citations and 26 peer-reviewed articles were finally included in the review. Considerable heterogeneity was observed regarding the methods of evaluating fine motor skills. The results of this review indicate that children and adolescents with ALL experienced fine motor limitations and upper extremity weakness either during or after cessation of treatment.

CONCLUSION

This scoping review presents a broad overview of the literature addressing fine motor difficulties in the pediatric population with ALL. Results accentuate the need to incorporate strengthening and occupational therapy training to preserve muscle strength and minimize future fine motor problems along the course of chemotherapeutic treatment. Little evidence was reported regarding the risk factors that may impair muscle strength and motor performance.

Neurocognitive Effects and Necrosis in Childhood Cancer Survivors Treated With Radiation Therapy: A PENTEC Comprehensive Review

PURPOSE

A PENTEC review of childhood cancer survivors who received brain radiation therapy (RT) was performed to develop models that aid in developing dose constraints for RT-associated central nervous system (CNS) morbidities.

METHODS AND MATERIALS

A comprehensive literature search, through the PENTEC initiative, was performed to identify published data pertaining to 6 specific CNS toxicities in children treated with brain RT. Treatment and outcome data on survivors were extracted and used to generate normal tissue complication probability (NTCP) models.

RESULTS

The search identified investigations pertaining to 2 of the 6 predefined CNS outcomes: neurocognition and brain necrosis. For neurocognition, models for 2 post-RT outcomes were developed to (1) calculate the risk for a below-average intelligence quotient (IQ) (IQ <85) and (2) estimate the expected IQ value. The models suggest that there is a 5% risk of a subsequent IQ <85 when 10%, 20%, 50%, or 100% of the brain is irradiated to 35.7, 29.1, 22.2, or 18.1 Gy, respectively (all at 2 Gy/fraction and without methotrexate). Methotrexate (MTX) increased the risk for an IQ <85 similar to a generalized uniform brain dose of 5.9 Gy. The model for predicting expected IQ also includes the effect of dose, age, and MTX. Each of these factors has an independent, but probably cumulative effect on IQ. The necrosis model estimates a 5% risk of necrosis for children after 59.8 Gy or 63.6 Gy (2 Gy/fraction) to any part of the brain if delivered as primary RT or reirradiation, respectively.

CONCLUSIONS

This PENTEC comprehensive review establishes objective relationships between patient age, RT dose, RT volume, and MTX to subsequent risks of neurocognitive injury and necrosis. A lack of consistent RT data and outcome reporting in the published literature hindered investigation of the other predefined CNS morbidity endpoints.

Use of Patient-Centered Technology and Digital Interventions in Pediatric and Adult Patients with Hematologic Malignancies

PURPOSE OF REVIEW

As society continues to advance in technology, it is important to address how this advancement can impact and enhance patient care. The purpose of this review is to identify patient-centered technology currently available for adult and pediatric patients with and those having survived hematologic malignancies. Given that patients with hematologic malignancies often have to adhere to strenuous medication regimens, coordinate care with many different providers, manage symptoms associated with treatment, and manage late effects associated with survivorship, they would benefit greatly from patient-centered technology aimed at decreasing these burdens.

RECENT FINDINGS

This review found various available digital interventions for this patient population and focuses on an overview of commercially available smartphone applications, patient portals, and technology for remote monitoring. In summary, many digital interventions exist for use in the medical care of oncology patients. The incorporation of these interventions can allow for more personalized medical care, better organization of treatment plans by caregivers at home, and easy delivery of accurate medical information.

The Impact of Gut Microbiota Changes on Methotrexate-Induced Neurotoxicity in Developing Young Rats

Methotrexate (MTX) is an essential part of therapy in the treatment of acute lymphoblastic leukemia (ALL) in children, and inferior intellectual outcomes have been reported in children who are leukemia survivors. Although several studies have demonstrated that the interaction between gut microbiota changes and the brain plays a vital role in the pathogenesis of chemotherapy-induced brain injury, preexisting studies on the effect of MTX on gut microbiota changes focused on gastrointestinal toxicity only. Based on our previous studies, which revealed that MTX treatment resulted in inferior neurocognitive function in developing young rats, we built a young rat model mimicking MTX treatment in a child ALL protocol, trying to investigate the interactions between the gut and brain in response to MTX treatment. We found an association between gut microbiota changes and neurogenesis/repair processes in response to MTX treatment, which suggest that MTX treatment results in gut dysbiosis, which is considered to be related to MTX neurotoxicity through an alteration in gut-brain axis communication.

Impact of Propofol Exposure on Neurocognitive Outcomes in Children With High-Risk B ALL: A Children's Oncology Group Study

PURPOSE

Many children treated for ALL develop long-term neurocognitive impairments. Increased risk of these impairments is associated with treatment and demographic factors. Exposure to anesthesia is an additional possible risk factor. This study evaluated the impact of cumulative exposure to anesthesia on neurocognitive outcomes among a multicenter cohort of children with ALL.

METHODS

This study was embedded in AALL1131, a Children's Oncology Group phase III trial for patients with high-risk B-ALL. In consenting patients age 6-12 years, prospective uniform assessments of neurocognitive function were performed during and at 1 year after completion of therapy. Exposure to all episodes of anesthetic agents was abstracted. Multivariable linear regression models determined associations of cumulative anesthetic agents with the primary neurocognitive outcome reaction time/processing speed (age-normed) at 1 year off therapy, adjusting for baseline neurocognitive score, age, sex, race/ethnicity, insurance status (as a proxy for socioeconomic status), and leukemia risk group.

RESULTS

One hundred and forty-four children, 76 (52.8%) males, mean age of 9.1 (min-max, 6.0-12.0) years at diagnosis, underwent a median of 27 anesthetic episodes (min-max, 1-37). Almost all patients were exposed to propofol (140/144, 97.2%), with a mean cumulative dose of 112.3 mg/kg. One year after therapy, the proportion of children with impairment (Z-score ≤-1.5) was significantly higher compared with a normative sample. In covariate-adjusted multivariable analysis, cumulative exposure to propofol was associated with a 0.05 Z-score decrease in reaction time/processing speed per each 10 mg/kg propofol exposure (P = .03).

CONCLUSION

In a multicenter and uniformly treated cohort of children with B-ALL, cumulative exposure to propofol was an independent risk factor for impairment in reaction time/processing speed 1 year after therapy. Anesthesia exposure is a modifiable risk, and opportunities to minimize propofol use should be considered.

Genetic Factors and Long-term Treatment-Related Neurocognitive Deficits, Anxiety, and Depression in Childhood Leukemia Survivors: An Exome-Wide Association Study

BACKGROUND

An increased risk of neurocognitive deficits, anxiety, and depression has been reported in childhood cancer survivors.

METHODS

We analyzed associations of neurocognitive deficits, as well as anxiety and depression, with common and rare genetic variants derived from whole-exome sequencing data of acute lymphoblastic leukemia (ALL) survivors from the PETALE cohort. In addition, significant associations were assessed using stratified and multivariable analyses. Next, top-ranking common associations were analyzed in an independent SJLIFE replication cohort of ALL survivors.

RESULTS

Significant associations were identified in the entire discovery cohort (N = 229) between the AK8 gene and changes in neurocognitive function, whereas PTPRZ1, MUC16, TNRC6C-AS1 were associated with anxiety. Following stratification according to sex, the ZNF382 gene was linked to a neurocognitive deficit in males, whereas APOL2 and C6orf165 were associated with anxiety and EXO5 with depression. Following stratification according to prognostic risk groups, the modulatory effect of rare variants on depression was additionally found in the CYP2W1 and PCMTD1 genes. In the replication SJLIFE cohort (N = 688), the male-specific association in the ZNF382 gene was not significant; however, a P value<0.05 was observed when the entire SJLIFE cohort was analyzed. ZNF382 was significant in males in the combined cohorts as shown by meta-analyses as well as the depression-associated gene EXO5.

CONCLUSIONS

Further research is needed to confirm whether the current findings, along with other known risk factors, may be valuable in identifying patients at increased risk of these long-term complications.

IMPACT

Our results suggest that specific genes may be related to increased neuropsychological consequences.

Chemobrain in blood cancers: How chemotherapeutics interfere with the brain's structure and functionality, immune system, and metabolic functions

Cancer treatment brings about a phenomenon not fully clarified yet, termed chemobrain. Its strong negative impact on patients' well-being makes it a trending topic in current research, interconnecting many disciplines from clinical oncology to neuroscience. Clinical and animal studies have often reported elevated concentrations of proinflammatory cytokines in various types of blood cancers. This inflammatory burst could be the background for chemotherapy-induced cognitive deficit in patients with blood cancers. Cancer environment is a dynamic interacting system. The review puts into close relationship the inflammatory dysbalance and oxidative/nitrosative stress with disruption of the blood-brain barrier (BBB). The BBB breakdown leads to neuroinflammation, followed by neurotoxicity and neurodegeneration. High levels of intracellular reactive oxygen species (ROS) induce the progression of cancer resulting in increased mutagenesis, conversion of protooncogenes to oncogenes, and inactivation of tumor suppression genes to trigger cancer cell growth. These cell alterations may change brain functionality, as well as morphology. Multidrug chemotherapy is not without consequences to healthy tissue and could even be toxic. Specific treatment impacts brain function and morphology, functions of the immune system, and metabolism in a unique mixture. In general, a chemo-drug's effects on cognition in cancer are not direct and/or in-direct, usually a combination of effects is more probable. Last but not least, chemotherapy strongly impacts the immune system and could contribute to BBB disruption. This review points out inflammation as a possible mechanism of brain damage during blood cancers and discusses chemotherapy-induced cognitive impairment.

A Review of Acute Lymphocytic Leukemia (ALL) in the Pediatric Population: Evaluating Current Trends and Changes in Guidelines in the Past Decade

Acute lymphocytic leukemia (ALL) is a commonly diagnosed cancer in children. Despite technological advancements to improve treatment and survival rates, there has been a steady increase in the incidence of ALL and treatment failures. This paper discusses the pathogenic interaction between genetic and environmental factors leading to childhood ALL. It evaluates the current treatment guidelines and notable obstacles leading to resistance, relapse, and treatment toxicities. The review evaluates a 10-year trend in the management guidelines of pediatric ALL through a systematic literature review of records from 2012 to 2023. Findings show that improvement in the five-year survival rates, notwithstanding rates of relapse and incurable diseases, is still high. Furthermore, several risk factors, including an interplay between genetic and environmental factors, are largely contributory to the outcome of ALL treatments and its overall incidence. Moreover, huge financial costs have remained a significant challenge in outcomes. There remains a need to provide individualized treatment plans, shared decision-making, and goals of care as parts of the management guidelines for the best possible outcomes. We expect that future advancements will increase overall survival rates and disease-free years.

Impact of socioeconomic status and chemotherapy on neurocognitive performance in children with brain tumors

Background

Although the relationship between radiation and neurocognition has been extensively studied in the pediatric brain tumor population, it is increasingly recognized that neurocognitive impairment is multifactorial. Therefore, we quantified the effect of socioeconomic status (SES) and chemotherapy on neurocognitive impairment and decline post-treatment.

Methods

Eligible patients included those diagnosed with a brain tumor at < 22 years of age with ≥1 neurocognitive assessment. Neurocognitive impairment was defined as performance 1.5 standard deviations below the normative mean using age-standardized measures of intellectual function. Neurocognitive decline was defined as a negative slope. Neurocognitive outcomes included Wechsler indices of Full-Scale Intelligence Quotient (IQ). Logistic regression identified variables associated with neurocognitive impairment. Longitudinal data was analyzed using linear mixed models.

Results

Eligible patients (n = 152, median age at diagnosis = 9.6 years) had a mean neurocognitive follow-up of 50.2 months. After accounting for age and receipt of craniospinal irradiation, patients with public insurance had 8-fold increased odds of impaired IQ compared to private insurance (odds ratio [OR]: 7.59, P < .001). After accounting for age, change in IQ was associated with chemotherapy use (slope: -0.45 points/year with chemotherapy vs. 0.71 points/year without chemotherapy, P = .012).

Conclusions

Public insurance, an indicator of low SES, was associated with post-treatment impairment in IQ, highlighting the need to incorporate SES measures into prospective studies. Chemotherapy was associated with change in IQ. Further work is needed to determine whether impairment associated with low SES is secondary to baseline differences in IQ prior to brain tumor diagnosis, brain tumor/therapy itself, or some combination thereof.

Agricultural intensification and childhood cancer in Brazil

Over the last several decades, Brazil has become both the world's leading soy producer and the world's leading consumer of hazardous pesticides. Despite identified links between pesticide exposure and carcinogenesis, there has been little population-level research on the effects of pesticide intensification on broader human health in Brazil. We estimate the relationship between expanded soy production-and related community exposure to pesticides-on childhood cancer incidence using 15 y of data on disease mortality. We find a statistically significant increase in pediatric leukemia following expanded local soy production, but timely access to treatment mitigates this relationship. We show that pesticide exposure likely occurs via water supply penetration. Our findings represent only the tip of the iceberg for substantial health externalities of high-input crop production and land use change. Our results are of particular interest in developing contexts with demand for intensified food production systems and underscore the need for stronger regulation of pesticides and increased public health attention to exposure in the broader community.

Early life cancer and chemotherapy lead to cognitive deficits related to alterations in microglial-associated gene expression in prefrontal cortex

Children that survive leukemia are at an increased risk for cognitive difficulties. A better understanding of the neurobiological changes in response to early life chemotherapy will help develop therapeutic strategies to improve quality of life for leukemia survivors. To that end, we used a translationally-relevant mouse model consisting of leukemic cell line (L1210) injection into postnatal day (P)19 mice followed by methotrexate, vincristine, and leucovorin chemotherapy. Beginning one week after the end of chemotherapy, social behavior, recognition memory and executive function (using the 5 choice serial reaction time task (5CSRTT)) were tested in male and female mice. Prefrontal cortex (PFC) and hippocampus (HPC) were collected at the conclusion of behavioral assays for gene expression analysis. Mice exposed to early life cancer + chemotherapy were slower to progress through increasingly difficult stages of the 5CSRTT and showed an increase in premature errors, indicating impulsive action. A cluster of microglial-related genes in the PFC were found to be associated with performance in the 5CSRTT and acquisition of the operant response, and long-term changes in gene expression were evident in both PFC and HPC. This work identifies gene expression changes in PFC and HPC that may underlie cognitive deficits in survivors of early life exposure to cancer + chemotherapy.

Contribution of Fatigue to Cognitive Dysfunction in Childhood Acute Lymphoblastic Leukemia Survivors

Late effects such as neurocognitive issues and fatigue have been reported in childhood acute lymphoblastic leukemia (cALL) survivors. Yet, their association is often poorly understood. In this study, we wished to (1) describe neurocognitive difficulties and fatigue in a well-characterized cohort of long-term cALL survivors and (2) explore the risk of having neurocognitive deficits as a function of fatigue. Childhood ALL survivors (N = 285) from three Canadian treatment centers completed the DIVERGT battery of cognitive tests and the PedsQL Multidimensional Fatigue Scale. We performed logistic regressions to assess the risk of a survivor to show cognitive deficits (<2.0 SD) depending on their fatigue levels. At least one cognitive deficit on the DIVERGT was present in 31% of participants. Domains primarily affected were working memory, fine motor skills, and verbal fluency. Sleep/rest fatigue in youths was higher than norms (d = 0.35). The risk for cognitive deficits increased independently with levels of fatigue in the domains of cognitive speed and flexibility, working memory, and verbal fluency. For every 10-point increase on general or sleep/rest fatigue on the 0-100 scale, there was a median +23-35% risk of showing a deficit among the 7 tasks significantly associated with fatigue. Fatigue may constitute a complementary target when searching to mitigate cognitive issues in this population.

Protocol for a prospective, longitudinal study of cognitive impairment in young patients with cancer: a multidisciplinary neuroscience approach (MyBrain)

INTRODUCTION

The aim of this research is to investigate young cancer patients' cognitive functioning and the underlying neurobiological mechanisms when cognitive functions are impaired. The MyBrain protocol is a multidisciplinary study that investigates cancer-related cognitive impairment in children, adolescents and young adults, combining neuropsychology, cognitive neuroscience and cellular neuroscience. The study is exploratory with a wide focus on trajectories of cognitive functions from diagnosis to the end of treatment and into survivorship.

METHODS AND ANALYSIS

Prospective longitudinal study including patients diagnosed with non-brain cancers at age 7-29 years. Each patient is paired with a control matched on age and social circle.

PRIMARY OBJECTIVE

Evaluation of neurocognitive function over time.

SECONDARY OBJECTIVES

Evaluation of self-perceived quality of life and fatigue, P300 in an electroencephalography (EEG) oddball paradigm, power spectrum in resting state EEG, serum and cerebrospinal fluid levels of biomarkers of neuronal damage, neuroplasticity, proinflammatory and anti-inflammatory markers and their association with cognitive function.

ETHICS AND DISSEMINATION

The study is approved by the Regional Ethics Committee for the Capital Region of Denmark (no. H-21028495), and the Danish Data Protection Agency (no. P-2021-473). Results are expected to guide future interventions to prevent brain damage and support patients with cognitive difficulties.

TRIAL REGISTRATION NUMBER

The article is registered at clinicaltrials.gov NCT05840575 (https://clinicaltrials.gov/ct2/show/NCT05840575).

Measuring what gets done: Using goal attainment scaling in a vocational counseling program for survivors of childhood cancer

BACKGROUND

Childhood cancer survivors face education and employment challenges due to physical, cognitive, and psychosocial effects of the disease and treatments, with few established programs to assist them. The objectives of this study were to describe the implementation of Goal Attainment Scaling (GAS) to evaluate an educational and vocational counseling program established for survivors of childhood cancer, and analyze patterns of program engagement and client outcomes, stratified by demographic and diagnostic characteristics.

METHODS

A population-based retrospective cohort study of childhood cancer survivors who were engaged with the Pediatric Oncology Group of Ontario's School and Work Transitions Program (SWTP) between January 2015 and December 2018 was utilized. Survivors were followed from SWTP engagement until May 30, 2019 to capture goal attainment. Individual goals were summarized across various demographic, disease, and treatment strata.

RESULTS

In total, 470 childhood cancer survivors (median age = 17.9, 58% male) set 4,208 goals in the SWTP during the study period. The mean length of observation was 130.8 weeks (SD = 56.9). Overall, 68% of the goals were achieved. Eighty-three percent of the goals related to further education. Clients diagnosed with a solid tumor set the most goals on average, followed by those with central nervous system tumors and leukemia/lymphoma.

CONCLUSIONS

The SWTP assists childhood cancer survivors in realizing their academic and vocational goals. Application of GAS in this setting is a feasible way to evaluate program outcomes. From the volume and breadth of the GAS goals set and achieved, the overall success of the SWTP appears strong.

Feasibility of serial neurocognitive assessment using Cogstate during and after therapy for childhood leukemia

PURPOSE

Neurocognitive impairment is frequently observed among survivors of childhood acute lymphoblastic leukemia (ALL) within the domains of attention, working memory, processing speed, executive functioning, and learning and memory. However, few studies have characterized the trajectory of treatment-induced changes in neurocognitive function beginning in the first months of treatment, to test whether early changes predict impairment among survivors. If correct, we hypothesize that those children who are most susceptible to early impairment would be ideal subjects for clinical trials testing interventions designed to protect against treatment-related neurocognitive decline.

METHODS

In this pilot study, we prospectively assessed neurocognitive functioning (attention, working memory, executive function, visual learning, and processing speed), using the Cogstate computerized battery at six time points during the 2 years of chemotherapy treatment and 1-year post-treatment (Dana-Farber Cancer Institute ALL Consortium protocol 11-001; NCT01574274).

RESULTS

Forty-three patients with ALL consented to serial neurocognitive testing. Of the 31 participants who remained on study through the final time point, 1 year after completion of chemotherapy, 28 (90%) completed at least five of six planned Cogstate testing time points. Performance and completion checks indicated a high tolerability (≥ 88%) for all subtests. One year after completion of treatment, 10 of 29 patients (34%) exhibited neurocognitive function more than 2 standard deviations below age-matched norms on one or more Cogstate subtests.

CONCLUSIONS

Serial collection of neurocognitive data (within a month of diagnosis with ALL, during therapy, and 1-year post-treatment) is feasible and can be informative for evaluating treatment-related neurocognitive impairment.

A Comprehensive Review of Neuropsychologic Studies Supports the Concept That Adequate Folinic Acid Rescue Prevents Post Methotrexate Neurotoxicity

PURPOSE

To review all studies providing evidence of the correlation between folinic acid (FA) rescue inadequacy and long-term cognitive damage in neuropsychological studies of children with acute lymphoblastic leukemia or osteogenic sarcoma treated under protocols using high-dose methotrexate and FA rescue.

METHODS

A comprehensive literature search was performed of all databases of the Web of Science Citation Index, during 1990-2020, for the terms: neuropsychological, neurocognitive, and cognitive, together with acute lymphoblastic (and lymphocytic) leukemia and osteogenic sarcoma. English-language peer-reviewed articles on neuropsychological assessments of children who had been treated with high-dose methotrexate without irradiation, and which included details of methotrexate and FA schedules, were selected. In addition, a personal database of over 500 reprints of articles from over 130 journals was reviewed on the subjects of methotrexate and FA and their side effects.

RESULTS

Three groups of studies were found and analyzed, with (1) no evidence of cognitive deterioration, (2) evidence of cognitive deterioration, and (3) more than 1 protocol grouped together, preventing separate analysis of any protocols, Protocols without cognitive deterioration reported adequate FA rescue, and those with cognitive deterioration reported inadequate FA rescue.

CONCLUSION

Neuropsychological evaluation supported inadequate FA being the cause of neurocognitive damage after high-dose methotrexate and that adequate FA rescue prevents this complication.

Comparison of Neurocognitive Functioning and Fine Motor Skills in Pediatric Cancer Survivors and Healthy Children

Background: The late treatment outcomes of pediatric brain tumors and of hematopoietic and lymphoid tissue tumors are an important focus of both rehabilitation and research. Neurocognitive and motor disorders induce further learning problems impeding social-emotional adaptation throughout a whole lifespan. Core deficits in short-term and working memory, visuospatial constructional ability, verbal fluency, and fine motor skills underlie distorted intellectual and academic achievement. This study aimed to assess the individual differences in cognitive ability and fine motor skills of pediatric tumor survivors and the age-matched healthy controls. Methods: A total of 504 tumor survivors after treatment and 646 age-matched healthy controls underwent neurocognitive and fine motor assessments. Findings: The group of tumor survivors scored significantly worse in both neurocognitive and fine motor skill in compared with the healthy control group. The pediatric brain tumor survivors (PBT group) performed worse in cognitive (p < 0.001 for verbal fluency and p < 0.001 for visuospatial constructional ability) and motor tests (p < 0.001) compared to the healthy controls. Hematopoietic and Lymphoid Tissues tumors survivors (THL group) performed worse in verbal fluency (p < 0.01) and visuospatial constructional test (p < 0.001) compared to the control group. Furthermore, the PBT group had worse results in visuospatial constructional ability (p < 0.05) and fine motor (p < 0.001) ability than the THL group. Significant differences between females and males were found in fine motor test performance in the PBT group (p < 0.05), as well as in verbal fluency (p < 0.01) and visuospatial constructional ability (p < 0.01) in the control group. Neurocognitive and fine motor skill characteristics in the THL group did not correlate with age.

Processing efficiency in pediatric cancer survivors: A review and operationalization for outcomes research and clinical utility

OBJECTIVE

Childhood cancer and cancer-related treatments disrupt brain development and maturation, placing survivors at risk for cognitive late effects. Given that assessment tools vary widely across researchers and clinicians, it has been daunting to identify distinct patterns in outcomes across diverse cancer types and to implement systematic neurocognitive screening tools. This review aims to operationalize processing efficiency skill impairment-or inefficient neural processing as measured by working memory and processing speed abilities-as a worthwhile avenue for continued study within the context of childhood cancer.

METHODS

A comprehensive literature review was conducted to examine the existing research on cognitive late effects and biopsychosocial risk factors in order to conceptualize processing efficiency skill trends in childhood cancer survivors.

RESULTS

While a frequently reported pattern of neurobiological (white matter) and cognitive (working memory and processing speed) disruption is consistent with processing efficiency skill impairment, these weaknesses have not yet been fully operationalized in this population. We offer a theoretical model that highlights the impacts of a host of biological and environmental factors on the underlying neurobiological substrates of cancer survivors that precede and may even predict long-term cognitive outcomes and functional abilities following treatment.

CONCLUSION

The unified construct of processing efficiency may be useful in assessing and communicating neurocognitive skills in both outcomes research and clinical practice. Deficits in processing efficiency may serve as a possible indicator of cognitive late effects and functional outcomes due to the unique relationship between processing efficiency skills and neurobiological disruption following cancer treatment. Continued research along these lines is crucial for advancing childhood cancer outcomes research and improving quality of life for survivors.

Central nervous system involvement in childhood acute lymphoblastic leukemia: challenges and solutions

Delivery of effective anti-leukemic agents to the central nervous system (CNS) is considered essential for cure of childhood acute lymphoblastic leukemia. Current CNS-directed therapy comprises systemic therapy with good CNS-penetration accompanied by repeated intrathecal treatments up to 26 times over 2-3 years. This approach prevents most CNS relapses, but is associated with significant short and long term neurotoxicity. Despite this burdensome therapy, there have been no new drugs licensed for CNS-leukemia since the 1960s, when very limited anti-leukemic agents were available and there was no mechanistic understanding of leukemia survival in the CNS. Another major barrier to improved treatment is that we cannot accurately identify children at risk of CNS relapse, or monitor response to treatment, due to a lack of sensitive biomarkers. A paradigm shift in treating the CNS is needed. The challenges are clear - we cannot measure CNS leukemic load, trials have been unable to establish the most effective CNS treatment regimens, and non-toxic approaches for relapsed, refractory, or intolerant patients are lacking. In this review we discuss these challenges and highlight research advances aiming to provide solutions. Unlocking the potential of risk-adapted non-toxic CNS-directed therapy requires; (1) discovery of robust diagnostic, prognostic and response biomarkers for CNS-leukemia, (2) identification of novel therapeutic targets combined with associated investment in drug development and early-phase trials and (3) engineering of immunotherapies to overcome the unique challenges of the CNS microenvironment. Fortunately, research into CNS-ALL is now making progress in addressing these unmet needs: biomarkers, such as CSF-flow cytometry, are now being tested in prospective trials, novel drugs are being tested in Phase I/II trials, and immunotherapies are increasingly available to patients with CNS relapses. The future is hopeful for improved management of the CNS over the next decade.

Neuropsychological surveillance model for survivors of pediatric cancer: A descriptive report of methodology and feasibility

Objective: Neuropsychological late effects of pediatric cancer may not become apparent for years after therapy; therefore, serial monitoring is necessary for detecting changes to ensure timely intervention. Unfortunately, lack of access to neuropsychologists, increased patient volume, insurance authorization and reimbursement issues, time required for neuropsychological evaluation, and practice effects related to repeat testing present many challenges to provision of neuropsychological care for survivors of childhood cancer. Models involving surveillance and monitoring have been proposed, though minimal data exist related to the implementation and feasibility of such models. Method: In this descriptive feasibility study, the Neuropsychology Consult Clinic (NCC) at Children's Hospital Los Angeles is presented, outlining a methodology and algorithm for neuropsychological surveillance of survivors of non-CNS pediatric cancer and an account of the first three years of clinic implementation. Participants included 215 survivors (x̅ age = 5.6 years), including 75.3% Latinx patients. Results: The overall clinic implementation was found to be feasible, with approximately 75% of patients "passing" the screening and 25% "failing" the screening. Clinical judgment only conflicted with the algorithm 8.6% of the time. However, several limitations to feasibility were noted, including validity concerns and ability/time to complete parent-reported outcomes using Spanish forms, as well as access to bilingual examiners. Conclusions: These preliminary data support the feasibility of the NCC model with limitations as outlined above. This is the first phase in a multiphase plan to develop an appropriate screening clinic for survivors of pediatric cancer, with the next phase focusing on sensitivity/specificity of measures.

Flow Cytometric Detection of Malignant Blasts in Cerebrospinal Fluid: A Biomarker of Central Nervous System Involvement in Childhood Acute Lymphoblastic Leukemia

Despite the excellent prognosis for children and adolescents with acute lymphoblastic lymphoma (ALL), the involvement of the central nervous system (CNS) represents a major therapeutic challenge. Patients who develop CNS relapse have a very poor prognosis, and since current methods cannot reliably identify patients with CNS involvement or patients at high risk of CNS relapse, all children with ALL receive CNS-directed treatment. The current golden standard for detecting CNS involvement is the assessment of cytomorphology on cytospin slides of cerebrospinal fluid (CSF). This technique is inadequate due to low sensitivity and reproducibility. Flow cytometric analysis of CSF represent a novel, highly specific and sensitive technique for the detection of leukemic cells in the CNS. In prospective studies, CSF flow cytometry demonstrated two to three times higher rates of CNS involvement at diagnosis of childhood ALL than conventional cytospin, and especially demonstrated superior sensitivity in detecting low-level CNS disease. CNS involvement determined via flow cytometry has been linked to a higher risk of CNS relapse and poor outcomes in several studies. In this review, we discuss the central analytical concepts of CSF flow cytometry and summarize the current evidence supporting the use of flow cytometric detection of malignant blasts as a biomarker of CNS involvement in childhood ALL.

Neuropathic pain and neurocognitive functioning in children treated for acute lymphoblastic leukemia

ABSTRACT

Children with acute lymphoblastic leukemia (ALL) often experience treatment-related neurocognitive deficits and significant pain. Pain may exacerbate these cognitive impairments. This study examined neuropathic pain and neurocognitive outcomes in survivors of childhood ALL treated with contemporary therapy on a clinical trial (NCT00137111). There were 345 survivors (45% female, M = 6.9 years at diagnosis) who completed neurocognitive assessments including measures of sustained attention, learning and memory, and parent ratings of attention during at least one of 4 time points: on-therapy (Induction and Reinduction), end of therapy, and 2 years post-therapy. At-risk performance was defined as a score at least 1SD below the age-adjusted mean. Data on neuropathic pain (events, duration, and severity according NCI Common Toxicity Criteria) and pharmacologic pain management (opioids and gabapentin) were ascertained. Results showed that 135 survivors (39%) experienced neuropathic pain during treatment. Compared with those without pain, survivors with pain had greater memory impairments at end of therapy (California Verbal Learning Test [CVLT]-Total, 24% vs 12%, P = 0.046). Within the pain group, survivors who experienced a greater number of pain events (CVLT-Total = -0.88, P = 0.023) and those who were treated with opioids (versus gabapentin) had poorer learning and memory performance (CVLT-Total = -0.73, P = 0.011; Short Delay = -0.57, P = 0.024; Long Delay = -0.62, P = 0.012; and Learning Slope = -0.45, P = 0.042) across time points. These are considered medium-to-large effects (SD = 0.45-0.88). Neuropathic pain may be a risk factor for learning problems after therapy completion, and treatment for pain with opioids may also adversely affect neurocognitive performance. Therefore, patients who experience pain may require closer monitoring and additional intervention for neurocognitive impairment.

Neurocognitive deficits in survivors of childhood acute myeloid leukemia

BACKGROUND

Although treatment of acute myeloid leukemia (AML) contains neurotoxic agents, studies investigating neurocognitive outcomes in children with AML are sparse. We evaluated late cognitive effects in children treated with a high-dose cytarabine based regimen, focusing on general intellectual ability and specific neurocognitive domains.

METHODS

We evaluated 12 survivors of childhood AML who were treated between 2006 and 2016 and completed the Wechsler Intelligence Scales. One-sample t-tests were used to compare full-scale intelligence quotient (FSIQ) and primary index scores to norms. The overall effect of index scores and subtests was examined with one-way ANOVA. Univariate analyses and multiple regression models examined demographic and clinical characteristics associated with FSIQ.

RESULTS

Participants who underwent the Wechsler Intelligence Scale for Children demonstrated impairment on working memory index and participants who underwent the Wechsler Adult Intelligence Scale showed low score in the subtests that reflect working memory, whereas they exhibited no statistical differences versus the population means for FSIQ. There were no significant differences in the overall effect of index scores and subtests. On univariate analysis, FSIQ were related to time since diagnosis and age at assessment, and both were significant predictors of FSIQ on multiple linear regression.

CONCLUSIONS

Survivors of childhood AML exhibited impairment of working memory, even if their FSIQ was within the normal range. Difficulties in specific cognitive domains are associated with reduced quality of life. It is important to identify survivors who are at risk and provide tailored interventions.

Social adjustment in survivors of acute lymphoblastic leukemia without cranial radiation therapy

OBJECTIVE

To evaluate group differences in social adjustment in survivors of pediatric acute lymphoblastic leukemia (ALL) compared to survivor siblings and controls; identify disease-related predictors of social adjustment in survivors; and explore whether executive functioning explained differences in social adjustment across groups and between disease-related predictors.

METHODS

Survivors of pediatric ALL (n = 38, average age at diagnosis = 4.27 years [SD = 1.97]; average time off treatment = 4.83 years [SD = 1.52]), one sibling (if available, n = 20), and one parent from each family were recruited from a long-term survivor clinic. Healthy age- and sex-matched controls (n = 38) and one parent from each family were recruited from the community. Parents completed the Behavioral Assessment System for Children, Parent Rating Scale (BASC-3) Social Withdrawal subscale as a measure of social adjustment, and the Behavior Rating Inventory of Executive Functions (BRIEF-2) as a measure of executive function for each of their children. Multilevel modeling and mediation analysis were used to achieve the study aims.

RESULTS

Parents reported that survivors had significantly worse social adjustment compared to controls (b = 6.34, p = .004), but not survivor siblings. Among survivors, greater time off treatment (b = 2.06, p = .058) and poorer executive functioning (b = 0.42, p = .006) were associated with worse social adjustment. Executive function did not mediate differences in social withdrawal between survivors and controls or the relationship between time off treatment and social withdrawal among survivors.

CONCLUSIONS

Survivors of pediatric ALL presenting to follow-up programs should be screened for difficulties with social adjustment. Future research should examine treatment- and nontreatment-related factors contributing to poorer social outcomes.

Translationally relevant mouse model of early life cancer and chemotherapy exposure results in brain and small intestine cytokine responses: A potential link to cognitive deficits

Survivors of acute lymphoblastic leukemia (ALL), the most common childhood cancer, are at increased risk for long-term cognitive problems, including executive function deficits. The chemotherapeutic agent methotrexate (MTX) is used to treat most ALL patients and is closely associated with cognitive deficits. To address how early life cancer chemotherapy leads to cognitive deficits, we developed a translationally relevant mouse model of leukemia survival that exposed mice to leukemic cells and chemotherapeutic drugs (vincristine and MTX, with leucovorin rescue) in early life. Male and female mice were tested several weeks later using novel object recognition (recognition memory) and 5-choice serial reaction time task (executive function). Gene expression of proinflammatory, white matter and synapse-associated molecules was assessed in the prefrontal cortex and small intestine both acutely after chemotherapy and chronically after cognitive testing. Early life cancer-chemotherapy exposure resulted in recognition memory and executive function deficits in adult male mice. Prefrontal cortex expression of the chemokine Ccl2 was increased acutely, while small intestine expression of the proinflammatory cytokine tumor necrosis factor-alpha was elevated both acutely (both sexes) and chronically (males only). Inflammation in the small intestine was correlated with prefrontal cortical proinflammatory and synaptic gene expression changes, as well as to executive function deficits. Collectively, these data indicate that the current protocol results in a robust mouse model in which to study cognitive deficits in leukemia survivors, and suggest that small intestine inflammation may represent a novel contributor to adverse CNS consequences of early life chemotherapy.

Total Body Irradiation in Haematopoietic Stem Cell Transplantation for Paediatric Acute Lymphoblastic Leukaemia: Review of the Literature and Future Directions

Total body irradiation (TBI) has been a pivotal component of the conditioning regimen for allogeneic myeloablative haematopoietic stem cell transplantation (HSCT) in very-high-risk acute lymphoblastic leukaemia (ALL) for decades, especially in children and young adults. The myeloablative conditioning regimen has two aims: (1) to eradicate leukaemic cells, and (2) to prevent rejection of the graft through suppression of the recipient's immune system. Radiotherapy has the advantage of achieving an adequate dose effect in sanctuary sites and in areas with poor blood supply. However, radiotherapy is subject to radiobiological trade-offs between ALL cell destruction, immune and haematopoietic stem cell survival, and various adverse effects in normal tissue. To diminish toxicity, a shift from single-fraction to fractionated TBI has taken place. However, HSCT and TBI are still associated with multiple late sequelae, leaving room for improvement. This review discusses the past developments of TBI and considerations for dose, fractionation and dose-rate, as well as issues regarding TBI setup performance, limitations and possibilities for improvement. TBI is typically delivered using conventional irradiation techniques and centres have locally developed heterogeneous treatment methods and ways to achieve reduced doses in several organs. There are, however, limitations in options to shield organs at risk without compromising the anti-leukaemic and immunosuppressive effects of conventional TBI. Technological improvements in radiotherapy planning and delivery with highly conformal TBI or total marrow irradiation (TMI), and total marrow and lymphoid irradiation (TMLI) have opened the way to investigate the potential reduction of radiotherapy-related toxicities without jeopardising efficacy. The demonstration of the superiority of TBI compared with chemotherapy-only conditioning regimens for event-free and overall survival in the randomised For Omitting Radiation Under Majority age (FORUM) trial in children with high-risk ALL makes exploration of the optimal use of TBI delivery mandatory. Standardisation and comprehensive reporting of conventional TBI techniques as well as cooperation between radiotherapy centres may help to increase the ratio between treatment outcomes and toxicity, and future studies must determine potential added benefit of innovative conformal techniques to ultimately improve quality of life for paediatric ALL patients receiving TBI-conditioned HSCT.

Long-term neuropsychological outcomes of survivors of young childhood brain tumors treated on the Head Start II protocol

Background

The Head Start treatment protocols have focused on curing young children with brain tumors while avoiding or delaying radiotherapy through using a combination of high-dose, marrow-ablative chemotherapy and autologous hematopoietic cell transplantation (AuHCT). Late effects data from treatment on the Head Start II (HS II) protocol have previously been published for short-term follow-up (STF) at a mean of 39.7 months post-diagnosis. The current study examines long-term follow-up (LTF) outcomes from the same cohort.

Methods

Eighteen HS II patients diagnosed with malignant brain tumors <10 years of age at diagnosis completed a neurocognitive battery and parents completed psychological questionnaires at a mean of 104.7 months' post-diagnosis.

Results

There was no significant change in Full Scale IQ at LTF compared to baseline or STF. Similarly, most domains had no significant change from STF, including verbal IQ, performance IQ, academics, receptive language, learning/memory, visual-motor integration, and externalizing behaviors. Internalizing behaviors increased slightly at LTF. Clinically, most domains were within the average range, except for low average mathematics and receptive language. Additionally, performance did not significantly differ by age at diagnosis or time since diagnosis. Of note, children treated with high-dose methotrexate for disseminated disease or atypical teratoid/rhabdoid tumor displayed worse neurocognitive outcomes.

Conclusions

These results extend prior findings of relative stability in intellectual functioning for a LTF period. Ultimately, this study supports that treatment strategies for avoiding or delaying radiotherapy using high-dose, marrow-ablative chemotherapy and AuHCT may decrease the risk of neurocognitive and social-emotional declines in young pediatric brain tumor survivors.

Association of language proficiency, sociodemographics, and neurocognitive functioning in dual-language Latino survivors of childhood acute lymphoblastic leukemia and lymphoma

BACKGROUND

Survivors of childhood acute lymphoblastic leukemia and lymphoma (ALL/LL) are at risk for cognitive dysfunction, but little is known about its relationship with language proficiency and sociodemographics.

PROCEDURE

In this cross-sectional cohort study of Latino survivors of childhood ALL/LL, English and Spanish language proficiency and cognitive and academic functioning were measured and their associations determined using paired t-tests, Pearson correlations, and linear regressions.

RESULTS

Participants (N = 57; 50.9% female) had mean ages (years ± SD) of 4.3 ± 2.6 at diagnosis and 10.6 ± 2.9 at testing (range 6-16); mean time post treatment was 3.7 ± 2.6 years. The majority (73.7%) had low socioeconomic status (SES). Most (78.8%) were dual-language learners in English and Spanish. English proficiency was graded as limited-to-fluent and was significantly higher than Spanish (p < .001). Higher SES was correlated with higher English proficiency (r = 0.31, p = .020). Males had higher Spanish proficiency (r = -0.32, p = .034). Controlling for SES and sex, English proficiency accounted for 43% of cognitive functioning variance (F = 14.86, p < .001), 55% of reading comprehension variance (F = 22.14, p < .001), and 21% of mathematics variance (F = 5.76, p = .002).

CONCLUSIONS

Low language proficiency correlated with SES but was independently associated with lower cognitive and academic functioning. Research and surveillance for neurocognitive late effects in Latino ALL/LL survivors should incorporate measures of language proficiency and SES to account for their effects on cognitive and academic functioning.

Novel next-generation sequencing-based methodologies to characterize the mutational consequences of (prenatal) chemotherapy exposure in noncancerous tissue

PURPOSE OF REVIEW

Although chemotherapeutics are considered as genotoxins for decades, their exact mutagenic impact on the genome of cancerous and normal cells of cancer patients was unknown for a long time. However, this knowledge is necessary to understand the long-term side effects of chemotherapy. A particular condition represents pregnant cancer patients being treated with chemotherapy. Since certain chemotherapeutics can cross the placenta, concerns exist about possible mutational effects on the fetus' genome with potential long-term health consequences.

RECENT FINDINGS

Recent advances of next-generation sequencing (NGS) techniques have opened possibilities to explore the exact mutational footprint of chemotherapies in healthy tissue from treated cancer patients. However, the ultra-low frequency of chemotherapy-induced mutations, introduction of technical artefacts, and inaccessibility of normal tissue has posed important limitations. This review discusses five state-of-the-art approaches that were recently designed to overcome these drawbacks.

SUMMARY

Results of the latest investigations give valuable insights into the genome-wide genotoxicity profile of frequently applied chemotherapies, with most of these drugs being associated with a signature of random base substitutions and small indels. Though these findings still might be limited to extrapolate to healthy tissue, they pave the way for studies on the origin of long-term chemotherapy-related adverse health effects.

Cognitive and behavioral risk factors for low quality of life in survivors of childhood acute lymphoblastic leukemia

BACKGROUND

With high survival rates for pediatric acute lymphoblastic leukemia (ALL), long-term quality of life is a prominent consideration in treatment. We concurrently evaluated cognition, behavior, and quality of life in child and adolescent ALL survivors and determined associations between them.

METHODS

The sample included 83 controls (mean age: 12.5 years) and 71 ALL survivors (mean age: 11.9 years, mean age at diagnosis: 3.8 years). Participants completed measures of general intellectual abilities, math achievement, and fine motor skills. Parents and teachers completed a survey assessing child participants' cognitive, behavioral, and emotional function. Parents additionally completed a survey about their child's quality of life.

RESULTS

Survivors had lower scores on measures of working memory, processing speed, timed math, and fine motor skills (effect size 0.5-1, p < 0.001). Parents identified more problems with executive function and learning in survivors than controls (effect size > 0.7, p < 0.001), and indicated a lower quality of life in all categories evaluated (effect size > 0.7, p < 10^-4). Reduced quality of life was associated with lower math achievement scores and with inattention and executive function problems.

CONCLUSIONS

ALL survivors experience diffuse cognitive, behavioral, and motor impairments, which are associated with reduced quality of life. These findings underscore the need to address these challenges in ALL survivors.

IMPACT

Compared with cancer-free peers, parents of childhood acute lymphoblastic leukemia survivors treated with chemotherapy only reported reduced quality of life. Math difficulties and behavioral problems increased the risk for reduced quality of life. Reduced quality of life is associated with mild cognitive and behavioral difficulties, suggesting that even relatively mild impairments have broad implications for ALL survivors. Screening and early intervention targeting cognitive and behavioral function may enhance quality of life for ALL survivors.

Development of an Eco-Biodevelopmental Model of Emergent Literacy Before Kindergarten: A Review

IMPORTANCE

Literacy has been described as an important social determinant of health. Its components emerge in infancy and are dependent on genetic, medical, and environmental factors. The American Academy of Pediatrics advocates a substantial role for pediatricians in literacy promotion, developmental surveillance, and school readiness to promote cognitive, relational, and brain development. Many children, especially those from minority and underserved households, enter kindergarten unprepared to learn to read and subsequently have difficulty in school.

OBSERVATIONS

Emergent literacy is a developmental process beginning in infancy. Component skills are supported by brain regions that must be adequately stimulated and integrated to form a functional reading network. Trajectories are associated with genetic, medical, and environmental factors, notably the home literacy environment, which is defined as resources, motivation, and stimulation that encourage the literacy development process. Eco-biodevelopmental models are advocated by the American Academy of Pediatrics, and these models offer insights into the neurobiological processes associated with environmental factors and the ways in which these processes may be addressed to improve outcomes. Emergent literacy is well suited for such a model, particularly because the mechanisms underlying component skills are elucidated. In addition to cognitive-behavioral benefits, the association of home literacy environment with the developing brain before kindergarten has recently been described via neuroimaging. Rather than a passive approach, which may subject the child to stress and engender negative attitudes, early literacy screening and interventions that are administered by pediatric practitioners can help identify potential reading difficulties, address risk factors during a period when neural plasticity is high, and improve outcomes.

CONCLUSIONS AND RELEVANCE

Neuroimaging and behavioral evidence inform an eco-biodevelopmental model of emergent literacy that is associated with genetic, medical, and home literacy environmental factors before kindergarten, a time of rapid brain development. This framework is consistent with recommendations from the American Academy of Pediatrics and provides insights to help identify risk factors and signs of potential reading difficulties, tailor guidance, and provide direction for future research.

Methotrexate Neurotoxicity Is Related to Epigenetic Modification of the Myelination Process

With the improvement of the survival rate of acute lymphoblastic leukemia (ALL) in children, some children ALL survivors reveal inferior intellectual and cognition outcome. Methotrexate (MTX), while serving as an essential component in ALL treatment, has been reported to be related to various neurologic sequelae. Using combined intrathecal (IT) and intraperitoneal (IP) MTX model, we had demonstrated impaired spatial memory function in developing rats, which can be rescued by melatonin treatment. To elucidate the impact of MTX treatment on the epigenetic modifications of the myelination process, we examined the change of neurotrophin and myelination-related transcriptomes in the present study and found combined IT and IP MTX treatment resulted in altered epigenetic modification on the myelination process, mainly in the hippocampus. Further, melatonin can restore the MTX effect through alterations of the epigenetic pathways.

Tumor-associated myeloid cells provide critical support for T-ALL

Despite harboring mutations in oncogenes and tumor suppressors that promote cancer growth, T-cell acute lymphoblastic leukemia (T-ALL) cells require exogenous cells or signals to survive in culture. We previously reported that myeloid cells, particularly dendritic cells, from the thymic tumor microenvironment support the survival and proliferation of primary mouse T-ALL cells in vitro. Thus, we hypothesized that tumor-associated myeloid cells would support T-ALL in vivo. Consistent with this possibility, in vivo depletion of myeloid cells results in a significant reduction in leukemia burden in multiple organs in 2 distinct mouse models of T-ALL and prolongs survival. The impact of the myeloid compartment on T-ALL growth is not dependent on suppression of antitumor T-cell responses. Instead, myeloid cells provide signals that directly support T-ALL cells. Transcriptional profiling, functional assays, and acute in vivo myeloid-depletion experiments identify activation of IGF1R as a critical component of myeloid-mediated T-ALL growth and survival. We identify several myeloid subsets that have the capacity to directly support survival of T-ALL cells. Consistent with mouse models, myeloid cells derived from human peripheral blood monocytes activate IGF1R and directly support survival of primary patient T-ALL cells in vitro. Furthermore, enriched macrophage gene signatures in published clinical samples correlate with inferior outcomes for pediatric T-ALL patients. Collectively, these data reveal that tumor-associated myeloid cells provide signals critical for T-ALL growth in multiple organs in vivo and implicate tumor-associated myeloid cells and associated signals as potential therapeutic targets.

Long-term neurocognitive and quality of life outcomes in survivors of pediatric hematopoietic cell transplant

PURPOSE

Pediatric patients who undergo hematopoietic cell transplant (HCT) are at risk for neurocognitive impairments, which can impact quality of life. Given limited long-term studies, we aimed to characterize the late neurocognitive outcomes in a cohort of pediatric HCT survivors.

METHODS

Eligible survivors (HCT at age < 21 year and ≥ 1 year post-HCT) completed a 60-question survey of neurocognitive function and quality of life, which included the Childhood Cancer Survivor Study Neurocognitive Questionnaire (CCSS-NCQ) and the Neuro-Quality of Life Cognitive Function Short Form (Neuro-QoL). Analyses of risk factors included univariate comparisons and multivariable logistic regression.

RESULTS

Participants (n = 199, 50.3% female, 53.3% acute leukemia, 87.9% allogeneic transplants) were surveyed at median age of 37.8 years (interquartile range [IQR] 28.5-48.8) at survey and median 27.6 years (IQR 17.0-34.0) from transplant. On the CCSS-NCQ, 18.9-32.5% of survivors reported impairments (Z score > 1.28) in task efficiency, memory, emotional regulation, or organization, compared with expected 10% in the general population (all p < 0.01). In contrast, survivors reported average Neuro-QoL (T score 49.6±0.7) compared with population normative value of 50 (p = 0.52). In multivariable regression, impaired Neuro-QoL (T score < 40) was independently associated with hearing issues (OR 4.97, 95% CI 1.96-12.6), history of stroke or seizure (OR 4.46, 95% CI 1.44-13.8), and sleep disturbances (OR 6.95, 95% CI 2.53-19.1).

CONCLUSIONS

Although long-term survivors of pediatric HCT reported higher rates of impairment in specific neurocognitive domains, cognitive quality of life was perceived as similar to the general population. Subsets of survivors with certain co-morbidities had substantially worse neurocognitive outcomes.

IMPLICATIONS FOR CANCER SURVIVORS

While the long-term impact of pediatric HCT can include neurocognitive deficits, survivors report average cognitive quality of life.

Linguistic-Cognitive Outcomes in Children with Acute Lymphoid Leukemia: An Exploratory Study

Background

Acute lymphoid leukemia (ALL) is the most prevalent cancer of childhood. Impairment in linguistic and memory skills is a possible late sequela in cancer survivors that can limit their quality of life and the overall performance of the individual in society. There is evidence that survivors of ALL treated exclusively with chemotherapy demonstrate significant differences in long-term linguistic and memory functions and also changes in neuroanatomical integrity. However, most studies described do not count on a speech-language pathologist in their team, which we consider important to discuss. Thus, the objective of the present study was to assess memory and vocabulary skills in the pediatric population diagnosed with acute lymphoid leukemia during chemotherapy treatment.

Materials and Methods

An observational cohort study was conducted over a 1.8-year period. Participants of this research were children diagnosed with ALL. All participants were assessed on their linguistic-cognitive skills (ie, vocabulary, short-term memory and lexical access). All data underwent statistical analyses.

Results

The results of the current study found no major significant difference in the linguistic-cognitive performance of children with ALL and their healthy controls. Regarding the linguistic variables, we believe that there should be a differentiation between the effects of the drugs and the effects of social communication skills on performance.

Conclusion

This first characterization of the linguistic-cognitive abilities of children with ALL did not identify differences between these children and their healthy peers, although we were able to identify variables regarding the multidisciplinary team and social communication that should be considered in future studies.

The Working Memory Network and Its Association with Working Memory Performance in Survivors of non-CNS Childhood Cancer

Childhood cancer and its treatment puts survivors at risk of low working memory capacity. Working memory represents a core cognitive function, which is crucial in daily life and academic tasks. The aim of this functional MRI (fMRI) study was to examine the working memory network of survivors of childhood cancer without central nervous system (CNS) involvement and its relation to cognitive performance. Thirty survivors (aged 7-16 years, ≥ 1 year after cancer treatment) and 30 healthy controls performed a visuospatial working memory task during MRI, including a low- and a high-demand condition. Working memory performance was assessed using standardized tests outside the scanner. When cognitive demands increased, survivors performed worse than controls and showed evidence for slightly atypical working memory-related activation. The survivor group exhibited hyperactivation in the right-hemispheric superior parietal lobe (SPL) in the high- compared to the low-demand working memory condition, while maintaining their performance levels. Hyperactivation in the right SPL coincided with poorer working memory performance outside the scanner in survivors. Even in survivors of childhood cancer without CNS involvement, we find neural markers pointing toward late effects in the cerebral working memory network.AbbreviationsfMRI: Functional magnetic resonance imaging; CNS: Central nervous system; MNI: Montreal Neurological Institute; SES: Socioeconomic status; SPL: Superior parietal lobe.

Cortical Morphometry and Its Relationship with Cognitive Functions in Children after non-CNS Cancer

Background: Childhood cancer survivors (Ccs) are at risk for cognitive late-effects, which might result from cortical alterations, even if cancer does not affect the brain. The study aimed to examine gray and white matter volume and its relationship to cognition. Methods: Forty-three Ccs of non-central nervous system cancers and 43 healthy controls, aged 7-16 years, were examined. Cognitive functions and fine motor coordination were assessed and T1-weighted images were collected for voxel-based morphometry. Results: Executive functions (p = .024, d = .31) were poorer in Ccs than controls, however still within the normal range. The volume of the amygdala (p = .011, ŋ² = .117) and the striatum (p = .03, ŋ² = .102) was reduced in Ccs. No significant structure-function correlations were found, neither in patients nor controls. Conclusion: Non-CNS childhood cancer and its treatment impacts on brain structures relevant to emotion processing.

Methylene tetrahydrofolate reductase A1298C polymorphisms influence the adult sequelae of chemotherapy in childhood-leukemia survivors

This retrospective correlation study investigated the putative link between methylene tetrahydrofolate reductase (MTHFR) A1298C mutations and chemotherapy-related brain function changes in adult childhood-leukemia survivors. To this end, we determined the relationship between the particular MTHFR1298 genotype (AA, AC or CC) of 31 adult childhood-leukemia survivors, and (1) their CSF Tau and phosphorylated Tau (pTau) levels at the time of treatment, (2) their adult performance intelligence quotient (PIQ), and (3) their regional brain connectivity using diffusion magnetic resonance imaging (dMRI) and resting-state functional MRI (rsfMRI). We confirmed that neuropathology markers Tau and pTau significantly increased in CSF of children after intrathecal methotrexate administration. Highest concentrations of these toxicity markers were found during the induction phase of the therapy. Moreover, CSF concentrations of Tau and pTau during treatment were influenced by the children’s particular MTHFR1298 genotype. CSF Tau (but not pTau) levels significantly dropped after folinic acid supplementation. At adult age (on average 13.1 years since the end of their treatment), their particular MTHFR1298 genotype (AA, AC or CC) influenced the changes in PIQ and cortical connectivity that we found to be related to their childhood exposure to chemotherapeutics. In summary, we suggest that homozygous MTHFR1298CC individuals are more vulnerable to the adult sequelae of antifolate chemotherapy.

Association between obesity and neurocognitive function in survivors of childhood acute lymphoblastic leukemia treated only with chemotherapy

BACKGROUND

Neurocognitive impairment and obesity are common adverse sequelae in survivors of childhood acute lymphoblastic leukemia (ALL); however, the association has not been investigated.

METHODS

Neurocognitive function was evaluated once in survivors of ALL who were at least 8 years old and 5 years from their diagnosis. In a cross-sectional analysis, the associations with the body mass index (BMI) category and Z score were examined. A longitudinal analysis used the overweight/obesity area under the curve (AUC), which was determined via the trapezoidal rule by a sum of the integrals defined by the BMI Z score at each time point and the time intervals of the BMI measurement.

RESULTS

For 210 survivors, the median BMI Z score at diagnosis was 0.17, which increased to 0.54 at the end of induction and to 0.74 at the neurocognitive assessment. In the cross-sectional analysis, overweight/obese survivors scored significantly lower than others on the measures of executive function (cognitive flexibility, planning, verbal fluency, working memory, and spatial construction; all P < .05), attention (attention span and risk taking; all P < .05), and processing speed (visual motor coordination, visual speed, and motor speed; all P < .05). In the longitudinal analysis, when the treatment period was subdivided into 4 time periods (induction, consolidation, early maintenance, and late maintenance), a greater overweight/obesity AUC during induction therapy was associated with worse cognitive flexibility (P = .01) and slower motor speed (P = .02), which persisted throughout the treatment.

CONCLUSIONS

Overweight/obesity was significantly associated with neurocognitive impairment during long-term follow-up, and this association started early in treatment for ALL. Novel early interventions to provide cognitive training and prevent weight gain are required for patients at risk.

Neurocognitive and Behavioral Outcomes of Chinese Survivors of Childhood Lymphoblastic Leukemia

Background

Increasing attention has been dedicated to investigate modifiable risk factors of late effects in survivors of childhood cancer. This study aims to evaluate neurocognitive and behavioral functioning in a relatively young cohort of survivors of childhood acute lymphoblastic leukemia (ALL) in Hong Kong, and to identify clinical and socio-environmental factors associated with these outcomes.

Methods

This analysis included 152 survivors of childhood ALL who were ≥5 years post-diagnosis (52% male, mean [SD] age 23.5[7.2] years at evaluation, 17.2[7.6] years post-diagnosis). Survivors completed performance-based neurocognitive tests, and reported their emotional and behavioral symptoms using the Child/Adult Behavior Checklist. Socio-environmental variables (living space, fatigue, physical activity, family functioning, and academic stress) were self-reported using validated questionnaires. Clinical variables and chronic health conditions were extracted from medical charts. Multivariable linear modeling was conducted to test identify factors associated with neurocognitive/behavioral outcomes, adjusting for current age, sex, age at diagnosis and cranial radiation. An exploratory mediation analysis was performed to examine the mediating effects of risk factors on neurocognitive and behavioral outcomes.

Results

As compared to population norms, a minority of survivors developed mild-moderate impairment in motor processing speed (36.2%), memory (9.2%) and attention measures (4.0%-10.5%). Survivors also reported attention problems (12.5%), sluggish cognitive tempo (23.7%) and internalizing (depressive, anxiety and somatic symptoms) problems (17.1%). A minority of survivors developed mild-moderate treatment-related chronic conditions (n=37, 24.3%). As compared to survivors without chronic conditions, survivors with chronic conditions had more executive dysfunction (B=5.09, standard error [SE]=2.05; P=0.014) and reported more attention problems (B=5.73, SE=1.43; P<0.0001). Fatigue and poor family functioning was associated with multiple measures of behavior problems (all P<0.001). A lower level of physical activity was correlated with more self-reported symptoms of inattention (B= -1.12, SE=0.38, P=0.004) and sluggish cognitive tempo (B=-1.22, SE=0.41, P=0.003). Exploratory analysis showed that chronic health conditions were associated with behavioral measures through fatigue as the mediator.

Conclusion

The majority of young Chinese survivors of ALL had normal cognitive and behavioral function. Regular monitoring of behavioral function should be performed on survivors who develop treatment-related chronic conditions. Health behavior and socio-environment factors may be potentially modifiable risk factors associated with health outcomes in survivors.

Opportunities, barriers, and recommendations in down syndrome research

BACKGROUND

Recent advances in medical care have increased life expectancy and improved the quality of life for people with Down syndrome (DS). These advances are the result of both pre-clinical and clinical research but much about DS is still poorly understood. In 2020, the NIH announced their plan to update their DS research plan and requested input from the scientific and advocacy community.

OBJECTIVE

The National Down Syndrome Society (NDSS) and the LuMind IDSC Foundation worked together with scientific and medical experts to develop recommendations for the NIH research plan.

METHODS

NDSS and LuMind IDSC assembled over 50 experts across multiple disciplines and organized them in eleven working groups focused on specific issues for people with DS.

RESULTS

This review article summarizes the research gaps and recommendations that have the potential to improve the health and quality of life for people with DS within the next decade.

CONCLUSIONS

This review highlights many of the scientific gaps that exist in DS research. Based on these gaps, a multidisciplinary group of DS experts has made recommendations to advance DS research. This paper may also aid policymakers and the DS community to build a comprehensive national DS research strategy.

Adaptive functioning and academic achievement in survivors of childhood acute lymphoblastic leukemia: A report from the Children's Oncology Group

PURPOSE

To characterize academic and adaptive skill outcomes in survivors of high-risk B-lineage acute lymphoblastic leukemia (HR B-ALL).

METHODS

Participants were 178 patients enrolled on a nontherapeutic clinical trial that aimed to characterize neurocognitive and functional outcomes (ie, academic achievement and adaptive skills) following treatment for childhood HR B-ALL. Eligible patients were treated on Children's Oncology Group AALL0232 clinical trial that included two treatment randomizations: methotrexate delivery (high or escalating dose) and corticosteroid (dexamethasone or prednisone). Academic achievement and adaptive skills were evaluated at one time point, 8-24 months after completing treatment.

RESULTS

Multivariable logistic regression showed no significant association between treatment variables and outcomes after accounting for age at diagnosis, sex, and insurance status. In multivariable analyses accounting for sex and insurance status, survivors <10 years old at diagnosis had significantly lower scores in Math (P = .02). In multivariable analyses accounting for sex and age at diagnosis, scores for children with US public health insurance were significantly lower than those with US private or military insurance across all academic and adaptive skills (all P-values ≤.04). Results from univariate analyses showed that boys had significantly lower scores than girls across all adaptive skill domains (all P-values ≤.04).

CONCLUSION

Regardless of treatment randomization, survivors of HR B-ALL <10 years at diagnosis are at risk for deficits in Math and overall adaptive functioning; overall adaptive skills for boys were significantly poorer. Screening and early intervention for patients at highest risk, particularly young patients and lower resourced families, should be prioritized.

Elaboration and refinement of a motivational communication training program for healthcare professionals in pediatric oncology: a feasibility and acceptability study

INTRODUCTION

A healthy lifestyle could have a positive impact in reducing the incidence of some long-term sequelae secondary to pediatric cancer treatments. Motivational communication (MC) is effective at improving healthy lifestyle habits, especially when patients experience change as a challenge. To date, there is no available intervention program using MC that promotes healthy lifestyles in pediatric oncology.

OBJECTIVES

The aim of this study was to develop the first MC training program for professionals in pediatric oncology and assess its feasibility and acceptability.

MATERIALS AND METHODS

Following standard procedures involving professionals, we developed a professional-targeted training named the Motivation Cafés, consisting in six sessions of core MC skills for healthcare professionals who wish to positively impact lifestyles of families in pediatric oncology. We used a mixed-methods quantitative-qualitative study to assess the program feasibility and acceptability. Professionals in nutrition and physical activity (N = 16) attended two rounds of the training and completed surveys to evaluate the training. They reported self-efficacy and knowledge in MC. Participation and retention rates were used to assess acceptability and feasibility, and a thematic analysis of the open-ended questions was performed to identify strengths and weaknesses of the program to further refine the program. We used non-parametric statistics to compare pre-post changes on measures of self-efficacy and knowledge in MC.

RESULTS

Attendance and retention (average 4.2/6 sessions completed) were high, suggesting very good adherence and feasibility. We also found high levels of acceptability and pertinence of the program (i.e. >90%). The results suggested probable improvements in self-efficacy and knowledge, but these were not statistically significant given the limited sample size.

CONCLUSION

The training Motivation Cafés is now ready to be pilot tested in pediatric cancer care centers.

Longitudinal Trajectories of Neurocognitive Functioning in Childhood Acute Lymphoblastic Leukemia

OBJECTIVE

Children with acute lymphoblastic leukemia (ALL) are at risk for neurocognitive deficits, and examining individual variability is essential to understand these risks. This study evaluated latent longitudinal trajectories and risk factors of neurocognitive outcomes in childhood ALL.

METHODS

There were 233 participants with ALL who were enrolled on a phase 3, risk-stratified chemotherapy-only clinical trial (NCT00137111) and who completed protocol-directed neurocognitive assessments [47.6% female, mean (SD) = 6.6 (3.7) years]. Measures of sustained attention, learning/memory, and parent ratings of attention were completed during and after treatment. Longitudinal latent class analyses were used to classify participants into distinct trajectories. Logistic regression was used to identify predictors of class membership.

RESULTS

Within the overall group, attention performance was below age expectations across time (Conners Continuous Performance Test detectability/variability, p < 0.01); memory performance and parent ratings were below expectations at later phases (California Verbal Learning Test learning slope, p < 0.05; Conners Parent Rating Scale, Revised attention/learning, p < 0.05). Most participants (80-89%) had stable neurocognitive profiles; smaller groups showed declining (3-6%) or improving (3-11%) trajectories. Older age (p = 0.020), female sex (p = 0.018), and experiencing sepsis (p = 0.047) were associated with greater attention problems over time. Lower baseline IQ was associated with improved memory (p = 0.035) and fewer ratings of attention problems (p = 0.013) over time.

CONCLUSIONS

Most patients with ALL have stable neurocognitive profiles. Smaller groups have significant impairments shortly after diagnosis or have worsening performance over time. A tiered assessment approach, which includes consideration of individual and clinical risk factors, may be useful for monitoring neurocognitive functioning during treatment and survivorship.

A Review of Acute and Long-Term Neurological Complications Following Haematopoietic Stem Cell Transplant for Paediatric Acute Lymphoblastic Leukaemia

Despite advances in haematopoietic stem cell transplant (HSCT) techniques, the risk of serious side effects and complications still exists. Neurological complications, both acute and long term, are common following HSCT and contribute to significant morbidity and mortality. The aetiology of neurotoxicity includes infections and a wide variety of non-infectious causes such as drug toxicities, metabolic abnormalities, irradiation, vascular and immunologic events and the leukaemia itself. The majority of the literature on this subject is focussed on adults. The impact of the combination of neurotoxic drugs given before and during HSCT, radiotherapy and neurological complications on the developing and vulnerable paediatric and adolescent brain remains unclear. Moreover, the age-related sensitivity of the nervous system to toxic insults is still being investigated. In this article, we review current evidence regarding neurotoxicity following HSCT for acute lymphoblastic leukaemia in childhood. We focus on acute and long-term impacts. Understanding the aetiology and long-term sequelae of neurological complications in children is particularly important in the current era of immunotherapy for acute lymphoblastic leukaemia (such as chimeric antigen receptor T cells and bi-specific T-cell engager antibodies), which have well-known and common neurological side effects and may represent a future treatment modality for at least a fraction of HSCT-recipients.