Neurocognitive Interventions for Children and Adolescents Surviving Cancer

Using diffusion MRI to understand white matter damage and the link between brain microstructure and cognitive deficits in paediatric medulloblastoma patients

PURPOSE

Survivors of medulloblastoma face a range of challenges after treatment, involving behavioural, cognitive, language and motor skills. Post-treatment outcomes are associated with structural changes within the brain resulting from both the tumour and the treatment. Diffusion magnetic resonance imaging (MRI) has been used to investigate the microstructure of the brain. In this review, we aim to summarise the literature on diffusion MRI in patients treated for medulloblastoma and discuss future directions on how diffusion imaging can be used to improve patient quality.

METHOD

This review summarises the current literature on medulloblastoma in children, focusing on the impact of both the tumour and its treatment on brain microstructure. We review studies where diffusion MRI has been correlated with either treatment characteristics or cognitive outcomes. We discuss the role diffusion MRI has taken in understanding the relationship between microstructural damage and cognitive and behavioural deficits.

RESULTS

We identified 35 studies that analysed diffusion MRI changes in patients treated for medulloblastoma. The majority of these studies found significant group differences in measures of brain microstructure between patients and controls, and some of these studies showed associations between microstructure and neurocognitive outcomes, which could be influenced by patient characteristics (e.g. age), treatment, radiation dose and treatment type.

CONCLUSIONS

In future, studies would benefit from being able to separate microstructural white matter damage caused by the tumour, tumour-related complications and treatment. Additionally, advanced diffusion modelling methods can be explored to understand and describe microstructural changes to white matter.

"Chemobrain" in childhood cancer survivors-the impact on social, academic, and daily living skills: a qualitative systematic review

PURPOSE

To examine children's experiences of chemotherapy-induced cognitive impairment--colloquially "chemobrain"--and the impact on children's social, academic, and daily living skills via a qualitative systematic review. Experiencing chemotherapy as a child, when the brain is still developing, may cause lifelong detriment to survivors' lives. There is a significant gap in understanding their lived experience, including the self-identified barriers that children face following treatment. Such a gap can only be fully bridged by listening to the child's own voice and/or parent proxy report through an exploration of the qualitative research literature.

METHODS

A search of MEDLINE, Embase, PsycINFO, and CINAHL databases was conducted. Inclusion criteria were qualitative studies with a focus on children (0-18 years) during and/or following chemotherapy treatment and explored children's experiences of chemobrain.

RESULTS

Two synthesized findings were identified from six studies. (1) Chemobrain has an academic and psychosocial impact, which may not be understood by education providers. (2) Children and their parents have concerns about their reintegration and adaptation to school, social lives, and their future selves as independent members of society. Children's experiences primarily related to changes in their academic and social functioning.

CONCLUSION

This review highlights two important considerations: (1) the lived experiences of pediatric childhood cancer survivors guiding where future interventions should be targeted, and (2) a need to perform more qualitative research studies in this area, as well as to improve the quality of reporting among the existing literature, given that this is a current gap in the field.

Effects of Dopamine Receptor Antagonists and Radiation on Mouse Neural Stem/Progenitor Cells

Background

Dopamine receptor antagonists are psychotropic drugs that have been originally developed against psychiatric disorders. We recently identified dopamine receptor antagonists as potential anti-cancer agents and some have entered clinical trials against glioblastoma. Radiotherapy is known to cause cognitive impairment in patients receiving cranial irradiation through the elimination of neural stem/progenitor cells and subsequent loss of neurogenesis.

Methods

Using transgenic mice that report the presence of neural stem/progenitor cells through Nestin promoter-driven expression of enhanced green fluorescent protein, the effects of dopamine receptor antagonists alone or in combination with radiation on murine neural stem/progenitor cells were assessed in sphere-formation assays, flow cytometry and immunofluorescence in vitro and in vivo .

Results

We report that several dopamine receptor antagonists show sex-dependent effects on neural stem/progenitor cells both in vitro and in vivo . Hydroxyzine, trifluoperazine, amisulpride, nemonapride or quetiapine alone or in combination with radiation significantly increased the number of neural stem/progenitor cells in female neurospheres but not in male mice. Dopamine receptor antagonists either protected neural stem/progenitor cells from radiation or expanded the stem cell pool, thus indicating that this combination therapy against glioblastoma will not increase radiation-induced cognitive decline through increasing elimination of neural stem/progenitor cells and subsequent loss of neurogenesis.

Conclusions

We conclude that a therapeutic window for dopamine receptor antagonists in combination with radiation potentially exist, making it a novel combination therapy against glioblastoma. Normal tissue toxicity of this combination potentially differs depending on age and sex and should be taken into consideration when designing clinical trials.

Key Points

- Neural stem/progenitor cells show sex-dependent sensitivity to dopamine receptor antagonists- Dopamine receptor antagonists active against GBM increase Neural stem/progenitor cells counts.

Importance of the Study

Combination therapy of dopamine receptor antagonists with radiation have entered clinical trials against glioblastoma but the normal tissue toxicity of this combination has not been fully explored yet. Here we present evidence that some dopamine receptor antagonists show sex-dependent effects on neural stem/progenitor cells either by protecting neural stem/progenitor cells from radiation or inducing an expansion of the stem cell pool, suggesting that this combination therapy against glioblastoma will not increase radiation-induced cognitive decline through increasing elimination of neural stem/progenitor cells and subsequent loss of neurogenesis. Normal tissue toxicity of this combination potentially differs depending on age and sex and should be further explored in clinical trials.

Impact of home-based cognitive or academic intervention on working memory and mathematics outcomes in pediatric brain tumor survivors: the Keys to Succeed pilot randomized controlled clinical trial

Pediatric brain tumour survivors experience deficits in mathematics and working memory. An open question is whether it is most optimal to target direct cognitive skills (i.e. working memory) or focus on specific academic outcomes (i.e. mathematics) for in remediation. We conducted a pilot randomized controlled trial to determine the feasibility of comparing a working memory versus mathematics intervention. Pediatric brain tumor survivors (7-17 years) were randomly assigned to Cogmed or JumpMath interventions, or an Active Control/Reading group. All participants received Educational Liaison support and completed ~12-weeks of home-based intervention with weekly, telephone-based consultation in one of the three conditions. Standardized assessments of auditory and visual working memory, mathematics calculation and reasoning were completed pre- and post- intervention. Twenty-nine participants completed the interventions; 94% of parents reported a high degree of satisfaction with the interventions and ease of implementation. Participants in JumpMath demonstrated improved mathematics calculation from pre- to post- intervention (p=0.02). Further, participants in both Cogmed and JumpMath showed evidence of pre- to post- intervention improvements in auditory working memory relative to controls (p=0.01). The Cogmed group also showed improvements in visual working memory (p=0.03). Findings suggest that targeted intervention is feasible in survivors of pediatric brain tumors, though with a relatively low recruitment rate. With preliminary findings of improved calculation and working memory following JumpMath and working memory following Cogmed, this pilot trial lays the groundwork for future programs that investigate different inteCognitiveRehabilitationrventions that may be applied to target the unique needs of each survivor.

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.

Predictors of Cognitive Performance Among Infants Treated for Brain Tumors: Findings From a Multisite, Prospective, Longitudinal Trial

PURPOSE

Infants treated for CNS malignancies experience a significantly poorer response to treatment and are particularly at risk for neuropsychological deficits. The literature is limited and inconsistent regarding cognitive outcomes among this group. We investigated predictors of cognitive outcomes in children treated for brain tumors during infancy as part of a large, prospective, multisite, longitudinal trial.

PATIENTS AND METHODS

One hundred thirty-nine infants with a newly diagnosed CNS tumor were treated with chemotherapy, with or without focal proton or photon radiation therapy (RT). Cognitive assessments were conducted at baseline, 6 months, 1 year, and then annually for 5 years. The median length of follow-up was 816 days (26.8 months). Neurocognitive testing included assessment of intellectual functioning (intellectual quotient [IQ]), parent ratings of executive functioning and emotional and behavioral functioning, and socioeconomic status.

RESULTS

At baseline, IQ, parent-reported working memory, and parent-reported adaptive functioning were worse than normative expectations. Baseline cognitive difficulties were associated with younger age at diagnosis and lower socioeconomic status. Linear mixed models did not demonstrate a decline in IQ over time. There were increased parent-reported attention and executive problems over time. Increased concerns were related to supratentorial tumor location and CSF diversion. There were no differences in cognitive outcomes based on treatment exposure (chemotherapy-only v chemotherapy with RT and proton v photon focal RT).

CONCLUSION

Even before adjuvant therapy, young children with brain tumors experience cognitive difficulties that can affect quality of life. Changes in cognitive functioning over time were dependent on tumor location and surgical factors rather than adjuvant therapy. These findings may serve to guide treatment planning and indicate targets for cognitive monitoring and intervention.

Interventions for Children with Neurocognitive Impairments in Resource-Limited Settings: A Systematic Review

Many children and adolescents around the world suffer from neurocognitive deficits due to chronic disorders, such as Human Immunodeficiency Virus (HIV) and malaria. Resource-limited settings exacerbate the risk of negative cognitive outcomes due to high prevalence of associated disorders, poverty, and limited access to interventions. Current literature does not provide consensus regarding the efficacy of interventions to support children with cognitive impairments in low-resource settings. This research aimed to identify and evaluate interventions for youth with neurocognitive deficits in resource-limited settings. A systematic review of peer-reviewed literature was conducted within five databases (PubMed, Web of Science, CINAHL, PsycInfo, and WHO Index Medicus). Cognitive impairment was broadly defined to be inclusive of aspects of intellectual and cognitive functioning (e.g., working memory, attention, executive function). The income status of the country or countries in which each study was located was determined according to World Bank Income Status. Studies conducted in countries classified as low- or middle-income were included. Since low-resource areas exist within high-income countries, the resource availability within study settings in high-income countries was systematically evaluated for inclusion. The search yielded 19 articles that met all inclusion criteria. Interventions included strategies involving caregiver training, computerized and non-computerized cognitive training, physical activity, and nutritional supplementation. Interventions were administered in medical facilities, educational facilities, or the home. The majority of the interventions targeted the domains of memory and attention. Overall, the efficacy of interventions was inconsistent. Further, results indicated that the relationship between cognitive improvement and intervention types was not consistent across cognitive domains. However, when evaluating studies on an individual basis, some strategies demonstrated clinically- and statistically-significant improvement in cognitive function among specific groups of children. The low article yield highlights that few researchers have evaluated pediatric cognitive support interventions in low-resource contexts. This review suggests support strategies that should be considered for future studies as neurocognitive screening capacity improves in resource-limited settings.

Psychosocial Late Effects in Adolescent and Young Adult Survivors of Childhood Cancer Diagnosed with Leukemia, Lymphoma, and Central Nervous System Tumor

Purpose: The prevalence of psychosocial late effects and quality of life in adolescent and young adult (AYA)-aged survivors of pediatric cancer have been studied. Methods: The study was conducted in AYA survivors who had been diagnosed with leukemia, lymphoma, or brain tumor, had completed treatment at least 1 year before the study, and were 15-39 years old at study enrollment. The control group consisted of healthy volunteers. A questionnaire comprised a demographic form, eight questions concerning mental health and the disease, and survey The European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30. Controls received a questionnaire without questions concerning an illness. Results: Most of survivors believed that cancer treatment might have a serious influence on their health. Survivors significantly more frequently declared using drugs: neuroleptics, tranquilizers, and antidepressants than controls. Survivors of leukemia demonstrated significantly more problems in cognitive functioning than lymphoma survivors. Females were significantly more disabled in emotional functioning than males. Young adults more often reported dysfunction in emotional functioning compared to adolescents. Survivors who were assessed ≥10 years since therapy reported significantly more disadvantage in social functioning than those assessed <10 years since treatment completion. Survivors reported significantly more disadvantages in social functioning than controls. Allogeneic hematopoietic stem cell transplantation survivors more often suffered cognitive limitations. Irradiated survivors more often attended psychological therapy. Conclusions: Survivors of pediatric cancer are vulnerable to consequences of oncological treatment, making their quality life significantly worse in comparison with healthy controls. They need to be monitored, supported, and educated.

Facilitating Transitions to Adulthood in Pediatric Brain Tumor Patients: the Role of Neuropsychology

PURPOSE OF REVIEW

Transition-age patients with history of a pediatric brain tumor are at significant risk for difficulties transitioning to adulthood. We review current transition models and the potential role of neuropsychology in the transition process for adolescent and young adult brain tumor survivors.

RECENT FINDINGS

Several recently developed healthcare transition models include consideration of patients' cognitive and functional capacities, yet currently available transition readiness tools are limited in scope and do not possess adequate normative data across pediatric medical populations. We explore the potential utility and added benefit of systematically incorporating neuropsychology in the transition process for pediatric brain tumor survivors. The literature supports increased evaluation and intervention targeted at psychosocial barriers to transition. Based on these findings, we propose a family-centered and multidisciplinary care model that promotes both medical and broader psychosocial transition processes. Neuropsychology is ideally suited to assess the wide-ranging areas encompassed in transition readiness and to facilitate the transition process.

Feasibility and potential benefits of an attention and executive function intervention on metacognition in a mixed pediatric sample

The term "metacognition" describes thinking about a cognitive phenomenon or, more simply put, thinking about thinking . Metacognition involves using knowledge about one's cognitive processes to change behavior, including monitoring and controlling cognition. Metacognition is vital for learning and is often more difficult for children with neurodevelopmental concerns (e.g. Attention Deficit Hyperactivity Disorder [ADHD], Fetal Alcohol Spectrum Disorder [FASD], Autism Spectrum Disorders [ASD]), possibly due to underlying deficits in attention and executive functioning (EF). The present study evaluated a 6- to 8-week cognitive intervention aimed at improving attention and EF and children's metacognitive abilities. Participants included a mixed sample of 50 children ages 6-12 years presenting with attention and/or EF deficits. Children within the active intervention group completed a game-based attention/EF intervention called Caribbean Quest (CQ), which combines process-specific and compensatory approaches to remediate attention and EF. Educational Assistants (EAs) supported children during gameplay by teaching explicit metacognitive strategies. Pre/post assessments included measures of attention and working memory (WM), metacognitive awareness (child, parent, and EA questionnaires), and metacognitive regulation (metacognitive monitoring and control). Results indicated post-intervention gains in WM, metacognitive awareness, and metacognitive regulation (self-monitoring and metacognitive control). These results provide preliminary support for CQ as potentially beneficial in improving aspects of EF and metacognition in children.

Consistent Physical Activity and Future Neurocognitive Problems in Adult Survivors of Childhood Cancers: A Report From the Childhood Cancer Survivor Study

PURPOSE

To investigate longitudinal associations between physical activity (PA) and neurocognitive problems in adult survivors of childhood cancer.

METHODS

A total of 12,123 5-year survivors diagnosed between 1970 and 1999 (median [range] age at diagnosis, 7 [0-21] years, time since diagnosis at baseline, 16 [6-30] years) and 720 siblings self-reported PA and neurocognitive problems. PA was collected at baseline, and PA and neurocognitive data were obtained 7 (1-12) years and 12 (9-14) years later. PA consistency was defined as any combination of ≥ 75 minutes of vigorous or 150 minutes of moderate activity per week on all surveys. Multiple linear regressions, conducted separately for CNS and non-CNS survivors, identified associations between PA consistency and neurocognitive outcomes (expected mean, 50; standard deviation [SD], 10). Mediating effects of body mass index (BMI) and chronic health conditions (CHCs) were evaluated.

RESULTS

Survivors were less likely than siblings to report consistent PA (28.1% v 33.6%) and more likely to report problems in Task Efficiency (T-scores mean ± SD: siblings, 50.0 ± 0.4; CNS, 61.4 ± 0.4; non-CNS, 53.3 ± 0.3), Emotion Regulation (siblings, 51.4 ± 0.4; CNS, 54.5 ± 0.3; non-CNS 53.4 ± 0.2), and Memory (siblings, 50.8 ± 0.4; CNS, 58.9 ± 0.4; non-CNS, 53.5 ± 0.2; all P < .001). Survivors of CNS cancers (52.8 ± 0.3) also reported poorer Organization than siblings (49.9 ± 0.4; P < .001). After adjusting for age at diagnosis, age at questionnaire, emotional distress, and cancer treatment exposures, consistent PA was associated with fewer neurocognitive problems compared with consistent inactivity for both CNS and non-CNS groups (T-score differences ranging from -7.9 to -2.2) and larger neurocognitive improvements over time (-6.0 to -2.5), all P ≤ .01. BMI and severe CHCs partially mediated the PA-neurocognitive associations, but the mediation effects were small (change in β ≤ 0.4).

CONCLUSION

Adult survivors of childhood cancer who report more consistent PA have fewer neurocognitive problems and larger improvements in these concerns many years after treatment.

Brain Activity Associated With Attention Deficits Following Chemotherapy for Childhood Acute Lymphoblastic Leukemia

BACKGROUND

The impact of contemporary chemotherapy treatment for childhood acute lymphoblastic leukemia on central nervous system activity is not fully appreciated.

METHODS

Neurocognitive testing and functional magnetic resonance imaging (fMRI) were obtained in 165 survivors five or more years postdiagnosis (average age = 14.4 years, 7.7 years from diagnosis, 51.5% males). Chemotherapy exposure was measured as serum concentration of methotrexate following high-dose intravenous injection. Neurocognitive testing included measures of attention and executive function. fMRI was obtained during completion of two tasks, the continuous performance task (CPT) and the attention network task (ANT). Image analysis was performed using Statistical Parametric Mapping software, with contrasts targeting sustained attention, alerting, orienting, and conflict. All statistical tests were two-sided.

RESULTS

Compared with population norms, survivors demonstrated impairment on number-letter switching (P < .001, a measure of cognitive flexibility), which was associated with treatment intensity (P = .048). Task performance during fMRI was associated with neurocognitive dysfunction across multiple tasks. Regional brain activation was lower in survivors diagnosed at younger ages for the CPT (bilateral parietal and temporal lobes) and the ANT (left parietal and right hippocampus). With higher serum methotrexate exposure, CPT activation decreased in the right temporal and bilateral frontal and parietal lobes, but ANT alerting activation increased in the ventral frontal, insula, caudate, and anterior cingulate.

CONCLUSIONS

Brain activation during attention and executive function tasks was associated with serum methotrexate exposure and age at diagnosis. These findings provide evidence for compromised and compensatory changes in regional brain function that may help clarify the neural substrates of cognitive deficits in acute lymphoblastic leukemia survivors.

Parenting a child with cancer: a couple-based approach

Couples co-parenting a child with cancer face significant stressors that can adversely affect their couple relationship. How parents respond as a couple may affect the psychological adjustment of each parent and the child, as well as the ability of the family to cope with the child's illness. The purpose of this study was to assess the feasibility and acceptability of a couple-based intervention for parents of children with cancer. We conducted a randomized pilot intervention study (N = 21 couples randomized with a 2:1 allocation to the couple-based intervention or education control) testing a six-session, telephone-based intervention that trained couples in relationship skills to help them care for their child, strengthen their relationship, and support each other. We examined feasibility and acceptability of the intervention to the parents. In this study, 56% of eligible couples agreed to participate; 82% of randomized couples completed post-intervention surveys, and 62% completed all six sessions. Satisfaction with the intervention was high (mean = 3.3 on a 4-point scale). Changes in both groups were small in magnitude and mixed in direction, with some outcomes favoring the couple-based intervention and other favoring the education condition. Supporting couples is important to optimize individual and parental functioning when a child has cancer. However, there are significant challenges to delivering couple-based interventions to these parents. More research is needed to establish optimal timing and content of couple-based interventions for these parents as well as feasible methods of delivery.

Brain Connectivity and Cognitive Flexibility in Nonirradiated Adult Survivors of Childhood Leukemia

Background

This study aimed to assess functional and structural brain connectivity in adult childhood leukemia survivors and the link with cognitive functioning and previously identified risk factors such as intrathecal methotrexate dose and age at start of therapy.

Methods

Thirty-one nonirradiated adult childhood leukemia survivors and 35 controls underwent cognitive testing and multimodal magnetic resonance imaging (resting state functional MRI, T1-weighted, diffusion-weighted, and myelin water imaging [MWI]). Analyses included dual regression, voxel-based morphometry, advanced diffusion, and MWI modeling techniques besides stepwise discriminant function analysis to identify the most affected executive cognitive domain. Correlations with discrete intrathecal MTX doses and (semi)continuous variables were calculated using Spearman's rank and Pearson's correlation, respectively. All correlation tests were two-sided. Positive and negative T-contrasts in functional and structural MRI analysis were one-sided.

Results

Survivors demonstrated lower functional connectivity between the default mode network (DMN) and inferior temporal gyrus (ITG; P < .008). Additionally, we observed higher fractional anisotropy (FA; P = .04) and lower orientation dispersion index (ODI; P = .008) at the left centrum semiovale, which could-given that several fiber bundles cross this region-suggest selective reduced integrity of the respective white matter tracts. Set shifting reaction time, a measure of cognitive flexibility, was mostly impaired and correlated with lower FA (r = -0.53, P = .003) and higher ODI (r = 0.40, P = .04) in survivors but not with DMN-ITG connectivity. There were no statistically significant differences between survivors and controls in WM or GM volume, nor was there a statistically significant correlation between imaging measurements and age at start of therapy or intrathecal methotrexate dose.

Conclusions

Adult, nonirradiated childhood leukemia survivors show altered brain connectivity, which is linked with cognitive flexibility.

Neurocognitive Sequelae in Adult Childhood Leukemia Survivors Related to Levels of Phosphorylated Tau

Central nervous system-directed prophylactic chemotherapy increases survival in childhood leukemia, but possible late neurocognitive sequelae remain a concern. We compared intellectual performance (WAIS IV), memory (AVLT), and executive functioning (ANT) between adult leukemia survivors (n = 31) and control individuals (n = 35). In survivors, cerebrospinal fluid (CSF) levels of phosphorylated Tau (p-Tau) during treatment and total intrathecal methotrexate dose correlated with adult intellectual performance (Pearson's and Spearman's coefficients, respectively). Long-term memory and attentional control, both maturing before survivors' mean age at diagnosis, were unaffected (P > .05 on all four subtests), in contrast to cognitive flexibility and information processing (P < .05 for eight of the subtests), which mature during adolescence. CSF p-Tau and methotrexate dose negatively correlated with intellectual performance (r = -0.414, P = .04 and r = -0.484, P = .007, respectively), but not with each other (r = 0.219, P = .29). These data identify CSF p-Tau as a predictor of late neurocognitive sequelae (in addition to methotrexate dose). Early identification of children at risk could inspire interventions to prevent or remediate chemotherapy-induced cognitive sequelae.

Cognitive Implications of Ototoxicity in Pediatric Patients With Embryonal Brain Tumors

PURPOSE

Sensorineural hearing loss (SNHL) is associated with intellectual and academic declines in children treated for embryonal brain tumors. This study expands upon existing research by examining core neurocognitive processes that may result in reading difficulties in children with treatment-related ototoxicity.

PATIENTS AND METHODS

Prospectively gathered, serial, neuropsychological and audiology data for 260 children and young adults age 3 to 21 years (mean, 9.15 years) enrolled in a multisite research and treatment protocol, which included surgery, risk-adapted craniospinal irradiation (average risk, n = 186; high risk, n = 74), and chemotherapy, were analyzed using linear mixed models. Participants were assessed at baseline and up to 5 years after diagnosis and grouped according to degree of SNHL. Included were 196 children with intact hearing or mild to moderate SNHL (Chang grade 0, 1a, 1b, or 2a) and 64 children with severe SNHL (Chang grade 2b or greater). Performance on eight neurocognitive variables targeting reading outcomes (eg, phonemics, fluency, comprehension) and contributory cognitive processes (eg, working memory, processing speed) was analyzed.

RESULTS

Participants with severe SNHL performed significantly worse on all variables compared with children with normal or mild to moderate SNHL (P ≤ .05), except for tasks assessing awareness of sounds and working memory. Controlling for age at diagnosis and risk-adapted craniospinal irradiation dose, performance on the following four variables remained significantly lower for children with severe SNHL: phonemic skills, phonetic decoding, reading comprehension, and speed of information processing (P ≤ .05).

CONCLUSION

Children with severe SNHL exhibit greater reading difficulties over time. Specifically, they seem to struggle most with phonological skills and processing speed, which affect higher level skills such as reading comprehension.

Adolescent survivors' information needs for transitions to postsecondary education and employment

BACKGROUND

Adolescent and young adult (AYA) survivors of cancer and central nervous system (CNS) tumors endure major life disruptions with their diagnosis, treatment, and the burden of emerging learning difficulties. Survivors and their parents often struggle to obtain more academic support as survivors transition through school. This study explored the knowledge and experience survivors and their parents need as they progress through school to college.

METHODS

This cross-sectional study examined childhood cancer and CNS tumor survivors, aged 11 to 21 years, with a known learning difficulty (Individual Education Plan, 504 Plan) and their parents. We assessed participants' knowledge of and experience with transition planning for postsecondary education and independent living.

RESULTS

Ninety-two AYA survivors and parents (45 survivors, 47 parents) completed the survey. High school-aged survivors described their learning difficulties better than middle school-aged survivors. Survivors estimated their abilities higher than did their parents. Despite a majority of survivors expecting to attend college, 68.5% of survivors and 57.9% of parents were not certain how to get special accommodations for standardized college entrance exams. Only 20.8% of survivors were aware of what a transition plan includes. Parents understood the transition planning process and when it should begin better than the students (P = 0.001), but many parents (40.0%) were still unsure.

CONCLUSIONS

AYA survivors and parents lack knowledge necessary to successfully transition to their goals after high school. Greater education is needed.

Using the Patient-Reported Outcomes Measurement Information System (PROMIS) to measure symptom burden reported by patients with brain tumors

BACKGROUND

Children with brain tumors can experience symptom burden throughout their disease continuum. The aim of the study was to evaluate symptom burden reported by children with brain tumors and factors that potentially were associated with their symptoms.

METHODS

Data from 199 children with brain tumors aged 7-22 (mean age = 14 years; 52% males; 76% white) were analyzed. Symptom burden was assessed using the Patient-Reported Outcomes Measurement Information System (PROMIS) via computerized adaptive testing (CAT)-anxiety, depression, fatigue, mobility, upper extremity function, peer relationship, and cognition. Patients and parents completed Symptom Distress Scales (SDS). Test statistics and ANOVA were used to evaluate relationships between PROMIS measures and potentially influential variables.

RESULTS

Significant results (P < 0.01) showing impact of symptom burden included: PROMIS measures correlated with SDSs reported by patients and parents on all comparisons. Fatigue, mobility, and upper extremity function were associated with Karnofsky functional performance status, number of treatment modalities (0-3), and time since last treatment (≤1 year, >1 year). Fatigue and cognition were associated with educational program (regular classroom without an individualized education plan vs those that had an individualized education plan); mobility and upper extremity function were associated with time since last radiation. Mobility, upper extremity function, and anxiety were associated with time since last chemotherapy.

CONCLUSIONS

Significant associations were found between PROMIS and SDS as well as clinical and demographic characteristics. Brief-yet-precise PROMIS CATs can be used to systematically assess symptom burden experienced by children with brain tumors.

Cognitive rehabilitation is advantageous in terms of fatigue and independence in pediatric cancer treatment: a randomized-controlled study

This study aimed to investigate the effect of task-oriented inpatient cognitive rehabilitation on fatigue perception and independence in daily activities. Forty (22 males, 18 females) children with pediatric cancer were randomized to either study [n = 22; 10.81 (1.33) years] or control [n = 18; 10.16 (1.24) years] groups. The study group received a cognitive rehabilitation intervention in addition to a routine therapy program, and the control group received a routine therapy program for 15 sessions. Cognitive status, fatigue, and daily life activity outcomes were assessed by blinded assessors in before and after interventions in the hospital setting. The study group showed a significant decrease in fatigue (P values for fatigue before, during, and after activity: P < 0.001) and in the control group (P values for fatigue only in during and post activity: P < 0.05). A statistically significant improvement was found in functional independence for the study group in all activities of daily living areas areas (P < 0.001), whereas no differences were found in the control group. Cognitive rehabilitation appears to provide beneficial effects in decreasing fatigue, improving functional status in activities of daily living, and increasing cognitive skills at the early stages in inpatient rehabilitation of pediatric cancer.

Methotrexate Affects Cerebrospinal Fluid Folate and Tau Levels and Induces Late Cognitive Deficits in Mice

Intravenous and/or intrathecal administration of the anti-folate drug methotrexate is a common chemotherapeutic procedure in childhood leukemia. Therapeutic and prophylactic efficacy of these procedures notwithstanding, the occurrence of late adverse effects remains a cause of clinical concern in leukemia survivors. We propose an experimental mouse model to mimic the impact of methotrexate exposure on brain biochemistry and cell proliferation, as well as behavioral and neurocognitive functioning at adult age. Female C57Bl6/J mouse pups received saline or methotrexate injection (20 mg/kg, i.p.). CSF and serum concentrations of folate metabolites and toxicity makers were analyzed at 4 h, 24 h, and 1 week following injection. Behavioral test battery performance was assessed at adult age (3-4 months). We found acute changes in serum and CSF levels of folate in exposed pups that coincided with increases in CSF Tau, whereas homocysteine in serum and CSF, and CSF levels of pTau were unchanged or remained below detection. In addition, methotrexate injection coincided with diminished hippocampal cell proliferation 1 week after methotrexate injection. At adult age, exposed mice displayed hippocampus-dependent deficits in the Morris water maze, whereas exploration and anxiety-related behaviors were largely unaffected. Particularly during the reference memory (probe) trial after reversal learning, methotrexate-exposed animals were less precise than controls. These findings demonstrate adult neurocognitive sequelae in a mouse model that can be attributed to the biochemical and cellular impact of early-life methotrexate exposure.

Neuropsychological Consequences for Survivors of Childhood Brain Tumor in Malaysia

Objective: This study aimed to evaluate neuropsychological consequences in survivors of childhood brain tumor.

Method: A case-control study was conducted over a period of 4 months in a tertiary referral center in Kuala Lumpur, Malaysia. Fourteen survivors of childhood brain tumor aged 7–18 years, who were off-treatment for at least 1 year and were in remission, and 31 unrelated healthy controls were recruited. The median age at diagnosis was 8.20 years (range: 0.92–12.96 years). The diagnoses of brain tumors were medulloblastoma, germ cell tumor, pineocytoma, pilocystic astrocytoma, suprasellar germinoma, and ependymoma. Eleven survivors received central nervous system irradiation. Seven tasks were selected from the Amsterdam Neuropsychological Tasks program to evaluate alertness (processing speed), and major aspects of executive functioning, such as working memory capacity, inhibition, cognitive flexibility, and sustained attention. Speed, stability and accuracy of responses were the main outcome measures.

Results: Survivors of childhood brain tumor showed statistically significant poorer performance on all tasks compared to healthy controls. Both processing speed and accuracy were impaired in the survivors, in particular under more complex task conditions. The survivors demonstrated deficits in alertness, sustained attention, working memory capacity, executive visuomotor control, and cognitive flexibility. Longer duration off treatment appeared to be correlated with poorer alertness, memory capacity, and inhibition.

Conclusion: Survivors of childhood brain tumor in our center showed impaired neuropsychological functioning. Development of less toxic treatment protocols is important to prevent late effects of cognitive deficits in survivors of childhood brain tumor.

Cognitive Changes in Cancer Survivors

Advances in cancer treatments have led to substantially improved survival for patients with cancer. However, many patients experience changes in cognition as a side effect of both cancer and cancer treatment. This occurs with both central nervous system (CNS) tumors and non-CNS tumors and in both children and adults. Studies of patients with non-CNS cancer have shown that cancer-related cognitive impairment (CRCI), which can include changes in memory, executive function, attention, and processing speed, occurs in up to 30% of patients prior to any treatment and in up to 75% of patients during treatment. A subset of patients with non-CNS and CNS cancer appear to be at higher risk for CRCI, so much research has gone into identifying who is vulnerable. Risk factors for CRCI in adults include cognitive reserve, age, genetic factors, and ethnicity; risk factors for children include genetic factors, female sex, younger age at diagnosis, chemotherapy dose, and both dose and field size for radiation. Although the field has made substantial strides in understanding and treating CRCI, more research is still needed to improve outcomes for both pediatric and adult cancer survivors.

Neuropsychological consequences of childhood medulloblastoma and possible interventions: A review

BACKGROUND

Children who have been treated for a medulloblastoma often suffer long-term cognitive impairments that often negatively affect their academic performance and quality of life. In this article, we will review the neuropsychological consequences of childhood medulloblastoma and discuss the risk factors known to influence the presence and severity of these cognitive impairments and possible interventions to improve their quality of life.

METHODS

This narrative review was based on electronic searches of PubMed to identify all relevant studies.

RESULTS

Although many types of cognitive impairments often emerge during a child's subsequent development, the core cognitive domains that are most often affected in children treated for a medulloblastoma are processing speed, attention and working memory. The emergence and magnitude of these deficits varies greatly among patients. They are influenced by demographic (age at diagnosis, parental education), medical and treatment-related factors (perioperative complications, including posterior fossa syndrome, radiation therapy dose, etc.), and the quality of interventions such as school adaptations provided to the child or rehabilitation programs that focus on cognitive skills, behavior and psychosocial functioning.

CONCLUSION

These patients require specialized and coordinated multidisciplinary rehabilitation follow-up that provides timely and adapted assessments and culminates in personalized intervention goals being set with the patient and the family. Follow-up should be continued until referral to adult services.

Executive Function Deficits in Seriously Ill Children-Emerging Challenges and Possibilities for Clinical Care

The past years have seen an incredible increase in the quality and success rates of treatments in pediatric medicine. One of the resulting major challenges refers to the management of primary or secondary residual executive function deficits in affected children. These deficits lead to problems in the ability to acquire, understand, and apply abstract and complex knowledge and to plan, direct, and control actions. Executive functions deficits are important to consider because they are highly predictive of functioning in social and academic aspects of daily life. We argue that current clinical practice does not sufficiently account for the complex cognitive processes in this population. This is because widely applied pharmacological interventions only rarely account for the complexity of the underlying neuronal mechanisms and do not fit well into possibly powerful "individualized medicine" approaches. Novel treatment approaches targeting deficits in executive functions in seriously ill children could focus on neuronal oscillations, as these have some specific relations to different aspects of executive function. Importantly, such treatment approaches can be individually tailored to the individuals' deficits and can be transferred into home-treatment or e-health solutions. These approaches are easy-to-use, can be easily integrated into daily life, and are becoming increasingly cost-effective.

Disseminability of computerized cognitive training: Performance across coaches

Cogmed is a computerized cognitive intervention utilizing coaches who receive standardized instruction in analyzing training indices and tailoring feedback to remotely monitor participant's performance. The goal of this study was to examine adherence, satisfaction, and efficacy of Cogmed across coaches. Survivors of pediatric brain tumors and acute lymphoblastic leukemia (N = 68) were randomized to intervention (Cogmed) or waitlist control. The intervention group was matched with one of two coaches. Cognitive assessments were completed before and after intervention, and participants and caregivers in the intervention group completed satisfaction surveys. T-tests showed no differences in adherence across coaches (number of sessions completed p = .38; d = .32). Noninferiority statistics were not consistently equivalent for satisfaction, but equivalence was supported for caregiver perceptions of pragmatic utility and participant perceptions of logistical ease of Cogmed. Equivalence was not consistently suggested for cognitive outcomes, but was supported on measures tapping relevant cognitive domains (attention, working memory, processing speed, academic fluency). This study suggests adherence can be maintained across coaches. While aspects of satisfaction and cognitive outcomes were equivalent, the possible influence of coach-based variables cannot be ruled out. Findings highlight challenges in standardizing the coaching component of multicomponent computerized interventions and the need for ongoing research to establish dessiminability.

Development of a Culturally Competent Service to Improve Academic Functioning for Latino Survivors of Acute Lymphoblastic Leukemia: Methodological Considerations

Many survivors of childhood acute lymphoblastic leukemia (ALL) develop neurocognitive deficits that compromise academic functioning, especially in the presence of sociodemographic risk factors. The extent to which these risk factors coexist for Latino ALL survivors is not well described, but with shifts in U.S. demographics and improved survival in ALL, culturally competent interventions are needed. The Achieving Best Cognitive Successes after Cancer service was designed and implemented by a team representing nursing, medicine, psychology, and social work. Service components include neurocognitve assessment and individualized intervention for treatment-related risks and improving academic success for school-aged ALL survivors. Interventions are child-focused and parent-directed, recognizing that parents are major sources of support and advocates for their children within school systems. The service was designed to be culturally appropriate for the predominantly Latino patient population at our center, based on (1) linguistic competency of children and parents; (2) multicultural and ecological considerations for urban, low socioeconomic status, and migrant populations; (3) literacy barriers; and (4) contextual factors. This report describes methodological considerations and practice implications relevant to the design and implementation of similar culturally competent services for Latino pediatric cancer survivors.

[Formula: see text]Executive functioning and health-related quality of life in pediatric sickle cell disease

Research consistently indicates that children with sickle cell disease (SCD) face multiple risk factors for neurocognitive impairment. Despite this, no empirical research to date has examined the impact of neurocognitive functioning on quality of life for this pediatric group. Thus, the current study aims to examine the relationship between executive functioning and quality of life in a sample of children with SCD and further explore psychosocial and family/caregiver resources as moderators of this relationship. A total of 45 children with SCD aged 8 to 16 years and their caregivers completed measures of quality of life, behavioral ratings of executive functioning, and psychosocial functioning. Hierarchical linear regression models were utilized to determine the impact of executive functioning on quality of life and further test the interaction effects of proposed moderating variables. Controlling for age, pain, and socioeconomic status (SES), executive functioning was found to significantly predict child- and parent-reported quality of life among youth with SCD. Psychosocial resources of the primary caregiver or family was not found to moderate the relationship between executive functioning and quality of life. These results provide the first empirical evidence that lower executive skills negatively predict quality of life for children with SCD, supporting clinical and research efforts which aim to establish efficacious interventions that target cognitive decrements within this pediatric population.

Multiprofessional follow-up programmes are needed to address psychosocial, neurocognitive and educational issues in children with brain tumours

AIM

The aim of this study was to coordinate the structured psychosocial, neurocognitive and educational follow-up of children treated for brain tumours with the medical protocol and apply the model in two Swedish healthcare regions.

METHODS

We invited all children living in the two regions, who had been diagnosed with a brain tumour from October 1, 2010, through June 30, 2012, to participate along with their parents. The follow-up programme evaluated the emotional status of the parents and patients and assessed the children's general cognitive level, working memory, speed of performance, executive functions and academic achievement from diagnosis through to adult care.

RESULTS

During the study period, 61 children up to the age of 17.1 years were diagnosed with a brain tumour, but 18 of these were excluded for various reasons. The majority of the mothers (70%) displayed significantly poor emotional status, as did 34% of the fathers and 21% of the children. The majority of the children (57%) also showed poor neurocognitive performance and needed special adaptations at school (66%).

CONCLUSION

Our findings indicate the need for coordinated, multiprofessional follow-up programmes, well anchored in the healthcare organisation, for children diagnosed with brain tumours.

Effect of motivation on academic fluency performance in survivors of pediatric medulloblastoma

It has been proposed previously that extrinsic motivation may enable survivors of childhood medulloblastoma to significantly improve aspects of neurocognitive performance. In healthy populations, enhanced motivation has been shown to promote academic fluency, a domain likely more relevant to the educational outcomes of pediatric medulloblastoma survivors than academic skill development. The present study investigates the effect of enhanced extrinsic motivation on fluent (i.e., accurate and efficient) academic performance in pediatric medulloblastoma survivors. Participants were 36 children, ages 7-18, who had completed treatment for medulloblastoma. Participants completed a neuropsychological battery that included administration of equivalent tasks on Forms A and B of the Woodcock-Johnson III Tests of Achievement. Half were randomly assigned to an incentive condition prior to the administration of Form B. Provision of a performance-based incentive resulted in statistically significant improvement, but not normalization of function, in performance on measures of academic fluency. No demographic, treatment-related, academic, neuropsychological, or self-perception variables predicted response to incentive. Findings suggest that academic performance of survivors may significantly improve under highly motivating conditions. In addition to implications for educational services, this finding raises the novel possibility that decreased motivation represents an inherent neuropsychological deficit in this population and provides a rationale for further investigation of factors affecting individual differences in motivational processes. Further, by examining effort in a context where effort is not inherently suspect, present findings also significantly contribute to the debate regarding the effects of effort and motivation on neuropsychological performance.

The potential utility of parent-reported attention screening in survivors of childhood cancer to identify those in need of comprehensive neuropsychological evaluation

BACKGROUND

Survivors of childhood cancer are at risk for neuropsychological late effects, yet identifying those in need of evaluation and obtaining needed services can be challenging for the medical team. Finding time- and cost-effective screening measures that can be used to identify children in need of evaluation is a clinical priority. Our objective was to investigate the association between parent-rated attention problems and related neuropsychological impairments in childhood cancer survivors as a means of identifying those at high risk for difficulties.

METHODS

Cognitive and psychosocial data of survivors who completed neuropsychological evaluations were retrospectively abstracted. Parents of 70 survivors of pediatric cancer (mean age, 11.6 years) completed the Conners Parent Rating Scale and the Child Behavior Checklist. Children also completed a measure of intellectual functioning. The 18 symptoms of inattention and hyperactivity were abstracted from the Conners questionnaire, and participants were classified according to whether or not they met attention deficit/hyperactivity disorder (ADHD) symptom criteria (≥6 inattentive symptoms).

RESULTS

Survivors who met symptom criteria for ADHD (27%) demonstrated greater impairments in IQ and working memory, but not processing speed, than survivors who did not. Meeting ADHD symptom criteria was also associated with greater externalizing and social problems but not more internalizing symptoms. ADHD symptom screening was associated with low sensitivity (range = 26.3%-69.2%) but stronger specificity (range = 75.0%-82.7%) for neuropsychological difficulties.

CONCLUSION

Parental ratings of attentional symptoms may be a useful way to screen survivors who may be in need of a full neuropsychological assessment.

Late effects in survivors of childhood CNS tumors treated on Head Start I and II protocols

BACKGROUND

Due to the devastating late effects associated with cranial irradiation in young children with central nervous system (CNS) tumors, treatment for these patients has evolved to include the use of intensive chemotherapy to either avoid or postpone irradiation. While survival outcomes have improved, late effects data in survivors treated on such regimens are needed.

OBJECTIVE

This multi-institutional study comprehensively describes late effects in survivors treated on the Head Start I/II protocols.

METHODS

Survivors of CNS tumors treated on Head Start I/II protocols were enrolled. Late effects data were collected using a validated parent-report questionnaire. Social, emotional, and behavioral functioning and quality of life were assessed using parent-report on the BASC-2 and CHQ-PF50 questionnaires.

RESULTS

Twenty-one survivors (medulloblastoma = 13, sPNET = 4, ATRT = 1, ependymoma = 3) were enrolled. Ten (48%) were irradiation-free. Late effects (frequency; median time of onset since diagnosis) included ≥ grade III hearing loss (67%; 3.9 years), vision (67%; 4.1 years), hypothyroidism (33%; 4 years), growth hormone (GH) deficiency (48%; 4.7 years), dental (52%; 7.1 years), and no cases of secondary leukemia. Irradiation-free (vs. irradiated) survivors reported low rates of hypothyroidism (0/10 vs. 7/11; P = 0.004) and GH deficiency (2/10 vs. 8/11; P = 0.03). The BASC-2 and CHQPF-50 mean composite scores were within average ranges relative to healthy comparison norms. Neither age at diagnosis nor irradiation was associated with these scores.

CONCLUSIONS

Irradiation-free Head Start survivors have lower risk of hypothyroidism and GH deficiency. Secondary leukemias are not reported. With extended follow-up, survivors demonstrate quality of life, social, emotional, and behavioral functioning within average ranges.

Developing interventions for cancer-related cognitive dysfunction in childhood cancer survivors

Survivors of childhood cancer frequently experience cancer-related cognitive dysfunction, commonly months to years after treatment for pediatric brain tumors, acute lymphoblastic leukemia (ALL), or tumors involving the head and neck. Risk factors for cancer-related cognitive dysfunction include young age at diagnosis, treatment with cranial irradiation, use of parenteral or intrathecal methotrexate, female sex, and pre-existing comorbidities. Limiting use and reducing doses and volume of cranial irradiation while intensifying chemotherapy have improved survival and reduced the severity of cognitive dysfunction, especially in leukemia. Nonetheless, problems in core functional domains of attention, processing speed, working memory and visual-motor integration continue to compromise quality of life and performance. We review the epidemiology, pathophysiology and assessment of cancer-related cognitive dysfunction, the impact of treatment changes for prevention, and the broad strategies for educational and pharmacological interventions to remediate established cognitive dysfunction following childhood cancer. The increased years of life saved after childhood cancer warrants continued study toward the prevention and remediation of cancer-related cognitive dysfunction, using uniform assessments anchored in functional outcomes.

[Treatment of cognitive impairments in oncology: a review of longitudinal controlled studies]

Various studies highlight cognitive impairments in cancer patients. This paper proposes a review of longitudinal controlled studies evaluating the efficacy of interventions aiming to reduce these cognitive impairments. Longitudinal controlled studies evaluating the efficacy of interventions aiming to reduce cognitive impairments in adult cancer patients and published between 1993 and 2013 were identified, with the exception of studies that implied patients suffering from CNS tumor or metastasis. Pharmacological interventions (n = 11) suggested the positive impact of modafinil on memory and executive functions. Non-pharmacological interventions (n = 10) suggested the positive impact of cognitive revalidation and stimulation programs, psycho-education and meditation on several memory, attentional and executive objective as well as subjective functions. Non-pharmacological interventions show more significant cognitive benefits than pharmacological interventions. Some longitudinal controlled studies support the usefulness of interventions aiming to reduce cognitive impairments in cancer patients. Further studies should evaluate the effectiveness of programs combining technics aiming to reduce cognitive impairments and psychotherapeutic technics aiming to support patients' coping with illness.

Longitudinal study of cognitive and academic outcomes after pediatric liver transplantation

OBJECTIVE

To determine the evolution of cognitive and academic deficits and risk factors in children after liver transplantation.

STUDY DESIGN

Patients ≥2 years after liver transplantation were recruited through Studies of Pediatric Liver Transplantation. Participants age 5-6 years at Time 1 completed the Wechsler Preschool and Primary Scale of Intelligence, 3rd edition, Wide Range Achievement Test, 4th edition, and Behavior Rating Inventory of Executive Function (BRIEF). Participants were retested at age 7-9 years, Time 2 (T2), by use of the Wechsler Intelligence Scales for Children, 4th edition, Wide Range Achievement Test, 4th edition, and BRIEF. Medical and demographic variables significant at P ≤ .10 in univariate analysis were fitted to repeated measures modeling predicting Full Scale IQ (FSIQ).

RESULTS

Of 144 patients tested at time 1, 93 (65%) completed T2; returning patients did not differ on medical or demographic variables. At T2, more participants than expected had below-average FSIQ, Verbal Comprehension, Working Memory, and Math Computation, as well as increased executive deficits on teacher BRIEF. Processing Speed approached significance. At T2, 29% (14% expected) had FSIQ = 71-85, and 7% (2% expected) had FSIQ ≤70 (P = .0001). A total of 42% received special education. Paired comparisons revealed that, over time, cognitive and math deficits persisted; only reading improved. Modeling identified household status (P < .002), parent education (P < .01), weight z-score at liver transplantation (P < .03), and transfusion volume during liver transplantation (P < .0001) as predictors of FSIQ.

CONCLUSIONS

More young liver transplantation recipients than expected are at increased risk for lasting cognitive and academic deficits. Pretransplant markers of nutritional status and operative complications predicted intellectual outcome.

Sex differences and the modulating effects of gonadal hormones on basal and the stressor-decreased newly proliferative cells and neuroblasts in dentate gyrus

This study was undertaken to assess sex differences and the modulating effects of gonad intactness and the estrous phase on basal and the stressor-decreased cell proliferation and early differentiation in Balb/C mouse dentate gyrus (DG). Besides, we compared the stress-reversing effects exerted by the presence of male and female Balb/C mouse odors in stressed male and female mouse DG in this regard. Female mice had lower baselines in the number of newly proliferated cells and neuroblasts than male mice. Although the stressor induced decreases in the number of newly proliferative cells and neuroblasts in both male and female DG, an obvious decrease in neuronal lineage commitment was observed in female DG. Moreover, ovariectomy induced decreases in baselines in the number of proliferative cells and neuroblasts but did not affect the stressor-induced decrease in neuronal lineage commitment in female DG. Interestingly, pro-estrous mice exhibited the stressor-decreased neuronal lineage commitment, while estrous and diestrous mice did not display such a decrease. Furthermore, orchidectomy did not affect basal or the stressor-decreased newly proliferative cells or neuroblasts in male DG. Finally, male odors were less effective than female odors in abolishing the stressor-decreased neuronal lineage commitment in female mice, while male and female odors were comparable in reversing the stressor-decreased newly proliferated cells and neuroblasts in male mice. The protective effects of mouse odors' company in the stressed male mouse DG were associated with local BDNF and NGF replenishment. Taken together, sexual differences in baselines in the number of newly proliferative cells, neuroblasts, and the sensitivity to stress-altered neuronal lineage commitment in the DG could be, in part, due to gonadal hormone differences between the two sexes. Mouse odors may reverse stressor-decreased newly proliferative cells and neuroblasts in male, but not in female, mouse DG by restoring BDNF and NGF levels.

Feasibility of conducting long-term follow-up of children and infants treated for CNS tumors on the same cooperative group clinical trial protocol

Given the barriers to conducting long-term assessment of neurocognitive and psychosocial functioning of those treated in infancy for central nervous system (CNS) tumors, a multi-site feasibility study was conducted. The primary objective was to demonstrate that it is feasible to identify, locate and assess the functioning of children treated on the same protocol 10-years post-treatment. Six sites obtained institutional approval, identified and recruited subjects, and obtained comprehensive neurocognitive and psychosocial data. All feasibility objectives were met. Barriers to participation included length of time for Institutional Review Board submission and review, clinical demands, limited eligible participants at individual institutions, difficulty locating long-term subjects and stipend/reimbursement concerns. Results indicate that long-term studies are feasible and essential given the need to address long-term issues of children treated at a young age for CNS tumors, especially as they relate to later academic and vocational planning, but require significant coordination and commitment of cooperative group and institutional resources.

Parent-reported cognition of children with cancer and its potential clinical usefulness

PURPOSE

Cognitive dysfunction is a common concern for children with brain tumors (BTs) or those receiving central nervous system (CNS) toxic cancer treatments. Perceived cognitive function (PCF) is an economical screening that may be used to trigger full, formal cognitive testing. We assessed the potential clinical utility of PCF by comparing parent-reported scores for children with cancer with scores from the general US population.

METHODS

Children (n = 515; mean age = 13.5 years; 57.0 % male) and one of their parents were recruited from pediatric oncology clinics. Most children (53.3 %) had a diagnosis of CNS tumor with an average time since diagnosis of 5.6 years. PCF was evaluated using the pediatric PCF item bank (pedsPCF), which was developed and normed on a sample drawn from the US general pediatric population. Children also completed computer-based neuropsychological tests. We tested relationships between PCF and clinical variables. Differential item functioning (DIF) was used to evaluate measurement bias between the samples.

RESULTS

No item showed DIF, supporting the use of pedsPCF in the cancer sample. PedsPCF differentiated children with (vs. without) a BT, p < 0.01, and groups defined by years since diagnosis, p < 0.01. It significantly (p < 0.05) correlated with computerized neuropsychological tests in 40 of 60 comparisons. Children with BTs were rated as having worse pedsPCF scores than the norm, regardless of years since diagnosis.

CONCLUSIONS

PCF significantly differentiated cancer survivors with various clinical characteristics. It is brief and easy to implement. PCF should be considered for routine care of pediatric cancer survivors.

Neurocognitive consequences of a paediatric brain tumour and its treatment: a meta-analysis

AIM

This meta-analysis provides a systematic review of studies into intellectual and attentional functioning of paediatric brain tumour survivors (PBTS) as assessed by two widely used measures: the Wechsler Intelligence Scale for Children (3rd edition; WISC-III) and the Conners' Continuous Performance Test (CPT).

METHOD

Studies were located that reported on performance of PBTS (age range 6-16y). Meta-analytic effect sizes were calculated for Full-scale IQ, Performance IQ, and Verbal IQ as measured by the WISC-III, and mean hit reaction time, errors of omission, and errors of commission as measured by the CPT. Exploratory analyses investigated the possible impacts of treatment mode, tumour location, age at diagnosis, and time since diagnosis on intelligence.

RESULTS

Twenty-nine studies were included: 22 reported on the WISC-III in 710 PBTS and seven on CPT results in 372 PBTS. PBTS performed below average (p(s) <0.001) on Full-scale IQ (Cohen's d=-0.79), Performance IQ (d=-0.90), and Verbal IQ (d=-0.54). PBTS committed more errors of omission than the norm (d=0.82, p<0.001); no differences were found for mean hit reaction time and errors of commission. Cranial radiotherapy, chemotherapy, and longer time since diagnosis were associated with lower WISC-III scores (p(s) <0.05).

INTERPRETATION

PBTS have seriously impaired intellectual functioning and attentiveness. Being treated with cranial radiotherapy and/or chemotherapy as well as longer time since diagnosis leads to worse intellectual functioning.

An fMRI investigation of working memory and its relationship with cardiorespiratory fitness in pediatric posterior fossa tumor survivors who received cranial radiation therapy

BACKGROUND

The present study investigated the relationship between cardiorespiratory fitness and executive functioning in pediatric brain tumor survivors who received cranial radiation. This population is known to show executive dysfunction and lower rates of aerobic exercise compared to peers.

PROCEDURE

Nine adolescent survivors of pediatric posterior fossa tumor completed an n-back working memory task during a functional MRI scan, as well as cardiorespiratory fitness testing on a cycle ergometer.

RESULTS

Neuroimaging findings indicated typical activation patterns associated with working memory, mainly in the frontal-parietal network. Higher cardiorespiratory fitness was related to better performance on a behavioral measure of working memory and more efficient neural functioning.

CONCLUSIONS

This study provides preliminary evidence that cardiorespiratory fitness may be related to executive functioning, particularly working memory, in pediatric brain tumor survivors. Descriptions of the brain regions recruited for working memory by pediatric brain tumor survivors may be used to inform future interventions or indicators of treatment efficacy.