Cognitive predictors of social adjustment in pediatric brain tumor survivors treated with photon versus proton radiation therapy

BACKGROUND

Pediatric brain tumor survivors are at risk for poor social outcomes. It remains unknown whether cognitive sparing with proton radiotherapy (PRT) supports better social outcomes relative to photon radiotherapy (XRT). We hypothesized that survivors treated with PRT would outperform those treated with XRT on measures of cognitive and social outcomes. Further, we hypothesized that cognitive performance would predict survivor social outcomes.

PROCEDURE

Survivors who underwent PRT (n = 38) or XRT (n = 20) participated in a neurocognitive evaluation >1 year post radiotherapy. Group differences in cognitive and social functioning were assessed using analysis of covariance (ANCOVA). Regression analyses examined predictors of peer relations and social skills.

RESULTS

Age at evaluation, radiation dose, tumor diameter, and sex did not differ between groups (all p > .05). XRT participants were younger at diagnosis (XRT M = 5.0 years, PRT M = 7.6 years) and further out from radiotherapy (XRT M = 8.7 years, PRT M = 4.6 years). The XRT group performed worse than the PRT group on measures of processing speed (p = .01) and verbal memory (p < .01); however, social outcomes did not differ by radiation type. The proportion of survivors with impairment in peer relations and social skills exceeded expectation; χ² (1) = 38.67, p < .001; χ² (1) = 5.63, p < .05. Household poverty predicted peer relation difficulties (t = 2.18, p < .05), and verbal memory approached significance (t = -1.99, p = .05). Tumor diameter predicted social skills (t = -2.07, p < .05).

CONCLUSIONS

Regardless of radiation modality, survivors are at risk for social challenges. Deficits in verbal memory may place survivors at particular risk. Results support monitoring of cognitive and social functioning throughout survivorship, as well as consideration of sociodemographic risk factors.

Long-term cognitive and academic outcomes among pediatric brain tumor survivors treated with proton versus photon radiotherapy

BACKGROUND

Proton radiotherapy (PRT) may be associated with less neurocognitive risk than photon RT (XRT) for pediatric brain tumor survivors. We compared neurocognitive and academic outcomes in long-term survivors treated with XRT versus PRT.

METHODS

Survivors underwent neurocognitive evaluation >1 year after craniospinal (CSI) or focal PRT or XRT. Groups were compared using separate one-way analyses of covariance for the CSI and focal groups.

RESULTS

PRT (n = 58) and XRT (n = 30) subgroups were similar on gender (66% male), age at RT (median = 6.5 years), age at follow-up (median = 14.6 years), and government assistance status (32%). PRT and XRT focal groups differed on follow-up interval, shunt history, and total RT dose (all p < .05), whereas PRT and XRT CSI groups differed on follow-up interval, baseline neurocognitive performance score, boost volume, and CSI dose (all p < .05). The PRT focal group outperformed the XRT focal group on inhibition/switching (p = .04). The PRT CSI group outperformed the XRT CSI group on inattention/impulsivity (both p < .05). Several clinical variables (i.e., RT dose, boost field, baseline performance) predicted neurocognitive outcomes (all p < .05). The PRT focal group performed comparably to population means on most neurocognitive measures, while both CSI groups performed below expectation on multiple measures. The XRT CSI group was most impaired. All groups fell below expectation on processing speed, fine motor, and academic fluency (most p < .01).

CONCLUSIONS

Findings suggest generally favorable neurocognitive and academic long-term outcomes following focal PRT. Impairment was greatest following CSI regardless of modality. Dosimetry and baseline characteristics are important determinants of outcome alone or in combination with modality.

Treatment age and neurocognitive outcomes following proton beam radiotherapy for pediatric low- and intermediate-grade gliomas

The relationship between age and neurocognitive functioning following proton beam radiotherapy (PRT) in low- and intermediate-grade gliomas (LIGG) has yet to be examined. Eighteen LIGG patients treated with PRT were prospectively enrolled and received annual neurocognitive evaluations of perceptual/verbal reasoning, working memory, and processing speed postradiotherapy. The median age at diagnosis was 8.2 years (range 1.0-14.7) and the median age at PRT was 9.9 years (range 4.2-17.0). Patients' neurocognitive performance did not change on any measure following PRT (p ≥ .142). We did not observe significant changes in cognitive function over time among a small group of LIGG patients treated with PRT.

QOL-01. LONGITUDINAL COMPARISON OF NEUROCOGNITIVE TRAJECTORIES IN PEDIATRIC MEDULLOBLASTOMA PATIENTS TREATED WITH PROTON VERSUS PHOTON RADIOTHERAPY

PURPOSE

By reducing dose to normal brain tissue, proton radiotherapy (PRT) may lessen neurocognitive risk traditionally associated with photon radiotherapy (XRT). We examined change in neurocognitive scores over time in pediatric medulloblastoma patients treated with PRT versus XRT.

METHODS

Neurocognitive scores from 79 patients (37 PRT, 42 XRT) were examined. Patients were treated between 2007–2018 on the same treatment protocols that differed only by craniospinal modality (PRT versus XRT). Change in scores over time since diagnosis were compared between groups.

RESULTS

Groups were similar on most demographic/clinical variables: sex (67.1% male), age at diagnosis (mean 8.6 years), CSI dose (median 23.4 Gy), length of follow-up (mean 4.3 years), and parental education (mean 14.3 years). Boost dose (p<0.001) and margin (p=0.001) differed between groups. Adjusting for covariates, the PRT group exhibited superior outcomes in global IQ, perceptual reasoning, and working memory versus the XRT group (all p<0.05). The XRT group exhibited significant decline in global IQ, working memory, and processing speed (all p<0.05). The PRT group exhibited stable scores in all domains except processing speed (p=0.003). Posterior fossa syndrome imparted risk independent of modality.

CONCLUSION

This is the first study comparing neurocognitive trajectories between pediatric patients treated for medulloblastoma with PRT versus XRT on comparable, contemporary protocols. PRT was associated with more favorable neurocognitive outcomes in most domains compared to XRT, although processing speed emerged as vulnerable in both groups. This is the strongest evidence to date of an intellectual sparing advantage with PRT in the treatment of pediatric medulloblastoma.

RONC-12. TREATMENT AGE AND NEUROCOGNITIVE OUTCOMES FOLLOWING PROTON BEAM RADIOTHERAPY FOR PEDIATRIC LOW GRADE GLIOMA

INTRODUCTION

Younger age at radiotherapy increases cognitive risk for patients with pediatric low grade glioma (LGG). We examined the impact of age at treatment on cognitive trajectories in LGG patients treated with proton radiotherapy (PRT) compared to patients treated without radiotherapy (surgery only; SO).

METHODS

We examined cognitive scores of 48 LGG patients on a prospective, longitudinal study. General linear mixed models evaluated change in cognitive scores over time.

RESULTS

The sample included 16 patients treated with PRT and 32 with SO (median follow-up=3.1 years, range 0.9–6.1). Median age of PRT patients was 8.2 years at diagnosis (range 1.0–14.4) and 9.4 years at PRT (range 4.2–16.7). 13 PRT patients also received surgery: 53.8% biopsy, 30.8% subtotal resection, 15.4% gross total resection. Tumor sites included: 31.2% hypothalamic/suprasellar, 25.0% optic pathway, 18.8% temporal, 25.0% other. Median age of SO patients was 8.2 years at diagnosis (range 2.9–18.6). Surgical outcomes were: 75.0% gross total resection, 21.9% biopsy/other. There were no group differences in diagnosis age, tumor volume, or shunt history (all p>0.05). Both PRT and SO groups displayed stable cognitive functioning over time (all p>0.1). Slopes (i.e., change in scores over time) did not differ between groups (all p>0.1). Age at treatment was not associated with slope or performance at last follow-up in either group (all p>0.05).

CONCLUSIONS

We observed stable cognitive functioning, independent of age at treatment, following PRT for LGG. Outcomes were similar to patients receiving surgery only. Further examination in a larger sample is warranted.

Prospective, longitudinal comparison of neurocognitive change in pediatric brain tumor patients treated with proton radiotherapy versus surgery only

BACKGROUND

Proton radiotherapy (PRT) reduces the volume of normal tissue receiving radiation dose, which may lead to better neurocognitive outcomes. We examined change in neurocognitive scores over time in pediatric brain tumor patients treated with proton craniospinal irradiation (CSI), proton focal RT, or surgery only.

METHODS

Patients received annual neurocognitive evaluations for up to 6 years. We examined Full Scale IQ (FSIQ), Verbal Comprehension Index (VCI), Perceptual Reasoning Index (PRI), Working Memory Index (WMI), and Processing Speed Index (PSI) scores. General linear mixed models examined change in scores over time by treatment group, adjusting for significant covariates.

RESULTS

Scores from 93 patients treated between 2012 and 2017 (22 proton CSI, 31 proton focal, and 40 surgery only) were examined. Treatment groups were similar on gender (51.6% male), age at treatment (median = 9.7 y), and length of follow-up (median = 2.9 y). The surgery only group had proportionately more gliomas (P < 0.001), and the proton CSI group had more infratentorial tumors (P = 0.001) and higher total RT dose (P = 0.004). The proton focal and surgery only groups exhibited stable neurocognitive scores over time across all indexes (all P > 0.05). In the proton CSI group, WMI, PSI, and FSIQ scores declined significantly (P = 0.036, 0.004, and 0.017, respectively), while VCI and PRI scores were stable (all P > 0.05).

CONCLUSIONS

Focal PRT was associated with stable neurocognitive functioning into survivorship. Outcomes were similar whether patients received focal PRT or no radiotherapy, even in neurocognitive domains known to be particularly radiosensitive. Proton CSI emerged as a neurocognitive risk factor, consistent with photon outcomes research.

Premorbid functioning as a predictor of outcome in pediatric brain tumor: An initial examination of the normalcy assumption

BACKGROUND

Research on neurodevelopmental outcome in survivors of pediatric brain tumor (BT) is often based on the assumption of normal development up to the onset of overt symptoms. We sought to verify the "normalcy assumption" and to investigate corollary issues including challenges inherent to the measurement of premorbid neurobehavioral functioning.

PROCEDURE

The Brain Radiation Investigative Study Consortium (BRISC) is a prospective longitudinal multisite study of 58 children diagnosed with BT. Premorbid functioning was assessed via retrospective parent report on standardized rating scales and detailed questionnaires. Findings were examined for the sample as a whole and in patients grouped by tumor histology (embryonal and non-embryonal).

RESULTS

Mean age at diagnosis was 9.84 years (range, 3-16). The overall sample showed low proportions of pre/postnatal risk factors and delays in development. The proportion of children with clinically significant premorbid attention (18%) problems based on the BASC-2 exceeded expectation of that in healthy children (6.68%). Similar findings were obtained for somatization (18%) and anxiety (14%). Delays in talking were significantly more common in children with embryonal than non-embryonal tumors (P = 0.02). The non-embryonal tumor group had significantly higher overall rates of premorbid psychosocial problems than the embryonal tumor group (P < 0.001).

CONCLUSIONS

We describe a rigorous approach to estimating premorbid developmental status in pediatric BT. The findings suggest mixed support for the "normalcy assumption" and highlight the complexity of this concept and need for further investigation. Our results also suggest the need for further study of potential premorbid correlates with tumor histology.

Cognitive mediators of adaptive functioning outcomes in survivors of pediatric brain tumors treated with proton radiotherapy

BACKGROUND

Cranial radiotherapy (RT) is associated with risk for cognitive and adaptive dysfunction. Proton RT (PRT) is a technique hypothesized to spare cognition by reducing exposure to nontarget brain tissue. However, little is known regarding functional outcomes in survivors of pediatric brain tumor (BT) treated with PRT. The present study examined the relationship between cognitive and adaptive outcomes in pediatric BT survivors post-PRT.

METHODS

Survivors treated with either focal (n = 33) or craniospinal irradiation (CSI; n = 37) PRT completed neurocognitive evaluations approximately 5 years post-treatment. Results of intelligence testing and ratings of adaptive functioning are reported. Mediation models examined the relationship among radiation field, cognition, and adaptive functioning.

RESULTS

The PRT CSI group demonstrated worse cognitive outcomes than the PRT Focal group across each cognitive index (Cohen's d = 0.56-0.70). Parent ratings of adaptive functioning were also worse in the PRT CSI group than the PRT Focal group (Global Adaptive Composite, d = 0.53; conceptual skills, d = 0.67). Cognitive performance fully mediated the relationship between radiation field and adaptive outcomes, while controlling for group differences in tumor histology and RT dose.

CONCLUSIONS

Focal PRT survivors demonstrated generally positive outcomes with weaknesses in processing speed and aspects of adaptive functioning. CSI exposure was associated with more consistently poor cognitive and adaptive outcomes. The increased risk for adaptive dysfunction in the PRT CSI group appeared due to the effects of CSI on cognition. Efforts to reduce the volume of tissue exposure to RT remain important.

[Formula: see text] Reliable change in pediatric brain tumor: A preliminary investigation

Children treated for brain tumor show evidence of declines in general intellectual abilities (i.e., IQ). Group-level data indicate subtle declines over time on average, but no study has utilized a clinical criterion to identify and describe a reliable change in survivors of pediatric brain tumor (PBT). In this study, we discuss the utility of reliable change index (RCI) methodology to supplement group-level analysis (e.g., repeated measures ANOVA). This pilot sample consisted of 22 children (M age = 10.47 years) treated for PBT who completed initial and follow-up assessments (M interval = 23.58 months). Cognitive data included composite scores from the WISC-IV. An RCI z-score was calculated for each participant on each composite score based on two different test-retest reliability coefficients. As a group, survivors of PBT did not demonstrate a statistically significant change from initial to follow-up on any WISC-IV composite score. When RCI was calculated based on reliability coefficients with shorter test-retest intervals provided by the test publisher, 77% of survivors demonstrated a reliable change in performance on at least one measure. The frequency of RCI decreases in working memory was significantly higher than expected. In contrast, only 32% of survivors showed reliable changes on at least one measure when RCI was based on a reliability coefficient derived from a clinical sample with a longer retest interval. This study demonstrates that highly divergent results may be obtained with RCI and the importance of the source of reliability estimates.

Neuropsychological functioning following surgery for pediatric low-grade glioma: a prospective longitudinal study

OBJECTIVE

High survival rates have led to an increased emphasis on the functional outcomes of children diagnosed with low-grade glioma. Most outcomes research has focused on risks associated with radiotherapy, but less is known about neuropsychological risks for patients treated with surgery alone. Here, the authors sought to examine the neuropsychological trajectories of children diagnosed with a low-grade glioma and monitored up to 6 years postsurgery. Secondarily, they explored demographic and clinical predictors of neuropsychological performance.

METHODS

The neuropsychological functioning of 32 patients (median age at diagnosis 10.0 years) was prospectively assessed annually for up to 6 years after surgery (median days from surgery at baseline = 72). Tumor location was predominately supratentorial (65.6%). A combination of performance-based and parent-reported measures was used to assess intelligence, memory, executive functioning, and fine motor control in all patients.

RESULTS

Binomial tests at the postoperative baseline revealed that the proportion of children falling below the average range (< 16th percentile) was significantly higher than the rate expected among healthy peers on measures of verbal memory, processing speed, executive functioning, and fine motor control (p < 0.05). Even so, linear mixed models indicated that neuropsychological functioning at the postoperative baseline did not significantly change over time for up to 6 years after surgery across all domains. A larger tumor size was associated with a slower reaction time (p < 0.01). A supratentorial tumor location and history of seizures were associated with more parent-reported executive difficulties (p < 0.01).

CONCLUSIONS

While radiotherapy is a known risk factor for neuropsychological deficits in pediatric brain tumor patients, findings in this study indicate that children treated for low-grade glioma with surgery alone (without radiotherapy or chemotherapy) remain susceptible to difficulties with memory, executive functioning, and motor functioning that persist over time. Over half of the children in the study sample required school support services to address neuropsychological weaknesses. Although low-grade glioma is often conceptualized as a benign tumor, children treated for this lesion require ongoing monitoring and intervention to address neuropsychological weaknesses resulting from the tumor itself as well as the surgery.

Superior Intellectual Outcomes After Proton Radiotherapy Compared With Photon Radiotherapy for Pediatric Medulloblastoma

PURPOSE

Proton radiotherapy (PRT) may lessen the neuropsychological risk traditionally associated with cranial radiotherapy for the treatment of pediatric brain tumors by reducing the dose to normal tissue compared with that of photon radiotherapy (XRT). We examined the change in intellectual scores over time in patients with pediatric medulloblastoma treated with craniospinal PRT versus XRT.

METHODS

Intelligence test scores were obtained for a sample of pediatric patients treated between 2007 and 2018 on the same medulloblastoma protocols that differed only in radiotherapy modality (PRT v XRT). Growth curve analyses compared change in scores over time since diagnosis between groups.

RESULTS

Longitudinal intelligence data from 79 patients (37 PRT, 42 XRT) were examined. Groups were similar on most demographic/clinical variables, including sex (67.1% male), age at diagnosis (mean, 8.6 years), craniospinal irradiation dose (median, 23.4 Gy), length of follow-up (mean, 4.3 years), and parental education (mean, 14.3 years). Boost dose (P < .001) and boost margin (P = .001) differed between groups. Adjusting for covariates, the PRT group exhibited superior long-term outcomes in global intelligence quotient (IQ), perceptual reasoning, and working memory compared with the XRT group (all P < .05). The XRT group exhibited a significant decline in global IQ, working memory, and processing speed (all P < .05). The PRT group exhibited stable scores over time in all domains with the exception of processing speed (P = .003).

CONCLUSION

To our knowledge, this is the first study to compare intellectual trajectories between pediatric patients treated for medulloblastoma with PRT versus those treated with XRT on comparable, contemporary protocols. PRT was associated with more favorable intellectual outcomes in most domains compared with XRT, although processing speed emerged as a vulnerable domain for both groups. This study provides the strongest evidence to date of an intellectual sparing advantage with PRT in the treatment of pediatric medulloblastoma.

Adaptive functioning in pediatric brain tumor survivors: An examination of ethnicity and socioeconomic status

BACKGROUND

Survivors of pediatric brain tumor are at risk for adaptive difficulties. The present study examined adaptive functioning in a multiethnic sample of survivors accounting for socioeconomic status, and whether demographic, diagnostic, and/or treatment-related variables predict adaptive outcomes.

METHOD

Participants included a multiethnic sample of survivors (58 Caucasian, 34 Hispanic, and 22 other non-Caucasian; M age = 14.05 years, SD = 4.33) who were approximately seven years post-treatment. Parents rated adaptive functioning and provided demographic information. Diagnostic and treatment-related information was abstracted from the electronic medical record.

RESULTS

Parent ratings of adaptive functioning were similar across Caucasian, Hispanic, and other non-Caucasian survivors covarying for family income and primary caregiver education, both of which served as proxies for socioeconomic status. All ethnic groups were rated lower than the normative mean in overall adaptive functioning as well as the specific domains of conceptual, social, and practical skills. Demographic, diagnostic, and treatment-related variables were differentially associated with adaptive functioning in survivors of pediatric brain tumor, though socioeconomic status emerged as a strong significant predictor of adaptive functioning domains.

CONCLUSIONS

Adaptive outcomes do not differ as a function of ethnicity after accounting for primary caregiver education and family income. Racial and ethnic minorities may be at increased risk for poorer outcomes given their overrepresentation at lower income levels. Assessing demographic and treatment-related variables early on may be helpful in identifying children likely to develop adaptive difficulties.

Neuropsychological and socioeconomic outcomes in adult survivors of pediatric low-grade glioma

BACKGROUND

Current estimates suggest that 75% of children diagnosed with a central nervous system (CNS) tumor will become 5-year survivors. However, survivors of childhood CNS tumors are at increased risk for long-term morbidity.

METHODS

To determine long-term neuropsychological and socioeconomic status (SES) outcomes, adult survivors of pediatric low-grade gliomas (n = 181) in the Childhood Cancer Survivor Study and a sibling comparison group that was frequency-matched by age and sex (n = 105) completed a comprehensive battery of standardized neuropsychological tests and an SES assessment. Multivariable regression models compared treatment-specific groups for neuropsychological and SES outcomes and evaluated associations with tumor location, age at diagnosis, sex, and age at evaluation.

RESULTS

In adjusted models, survivors treated with surgery and radiotherapy (surgery+RT; median age at diagnosis, 7 years; median age at assessment, 41 years) scored lower on estimated IQ than survivors treated with surgery only, who scored lower than siblings (surgery+RT, 93.9; surgery only, 101.2; siblings, 108.5; all P values <.0001). Survivors diagnosed at younger ages had low scores for all outcomes (P < .05) except for attention/processing speed. For SES outcomes, survivors treated with surgery+RT had lower occupation scores (odds ratio [OR], 2.6; 95% confidence interval [CI], 1.1-5.9), lower income (OR, 2.6; 95% CI, 1.3-5.0), and less education (OR, 2.1; 95% CI, 1.1-4.0) than those treated with surgery only.

CONCLUSIONS

Decades after treatment, survivors treated with radiotherapy and at younger ages had poorer neuropsychological and SES outcomes. Lifelong surveillance of survivors of pediatric low-grade gliomas may be warranted as life events, stages, and transitions (employment, family, and aging) present new challenges and risks.

Interactions between visual working memory and visual attention among survivors of pediatric acute lymphoblastic leukemia (ALL) and their healthy peers

Introduction: There is increasing concern for adverse cognitive late effects among survivors of pediatric acute lymphoblastic leukemia (ALL) given the widespread impact they have on academic achievement, particularly working memory and attention. We assessed performance among survivors and their healthy peers on a dual task paradigm measuring visual working memory (VWM) and visual attention independently and the dynamic relationship between the two. Assessing specific subsets within cognitive domains allows for understanding the distinct nature of cognitive impairments. Method: Participants were 34 survivors of ALL who have been off-treatment and disease free for 7.5 years; and 20 healthy controls, all between the ages of 10 and 18 years. We utilized behavioral single- and dual-task paradigms. In the dual tasks, participants maintained several items in VWM while performing a visual attention task (Eriksen Flanker Task) that required processing of a target stimulus while inhibiting the processing of distractor stimuli. The single tasks involved performing only the VWM task or only the visual attention task. Results: Results revealed survivors of ALL performed significantly worse than their healthy peers on the single visual attention task but not the single VWM task. Of particular interest, group differences were obtained on the dual VWM and visual attention tasks, such that the VWM and attention tasks reciprocally interfered with each other only among survivors and not their healthy peers. Conclusions: Our results highlight a core deficit in visual attention that is exacerbated by VWM demands among survivors of ALL. The implementation of tasks from cognitive neuroscience paradigms may be sensitive to cognitive impairments experienced by cancer survivors. Assessment and intervention practices among survivors of pediatric ALL are discussed.

Exercise ameliorates neurocognitive impairments in a translational model of pediatric radiotherapy

Background

While cranial radiation therapy (CRT) is an effective treatment, healthy areas surrounding irradiation sites are negatively affected. Frontal lobe functions involving attention, processing speed, and inhibition control are impaired. These deficits appear months to years after CRT and impair quality of life. Exercise has been shown to rejuvenate the brain and aid in recovery post-injury through its effects on neurogenesis and cognition.

Methods

We developed a juvenile rodent CRT model that reproduces neurocognitive deficits. Next, we utilized the model to test whether exercise ameliorates these deficits. Fischer rats (31 days old) were irradiated with a fractionated dose of 4 Gy × 5 days, trained and tested at 6, 9, and 12 months post-CRT using 5-choice serial reaction time task. After testing, fixed rat brains were imaged using diffusion tensor imaging and immunohistochemistry.

Results

CRT caused early and lasting impairments in task acquisition, accuracy, and latency to correct response, as well as causing stunting of growth and changes in brain volume and diffusion. Exercising after irradiation improved acquisition, behavioral control, and processing speed, mitigated the stunting of brain size, and increased brain fiber numbers compared with sedentary CRT values. Further, exercise partially restored global connectome organization, including assortativity and characteristic path length, and while it did not improve the specific regional connections that were lowered by CRT, it appeared to remodel these connections by increasing connectivity between alternate regional pairs.

Conclusions

Our data strongly suggest that exercise may be useful in combination with interventions aimed at improving cognitive outcome following pediatric CRT.

Dose-volume metrics and their relation to memory performance in pediatric brain tumor patients: A preliminary study

BACKGROUND

Advances in radiation treatment (RT), specifically volumetric planning with detailed dose and volumetric data for specific brain structures, have provided new opportunities to study neurobehavioral outcomes of RT in children treated for brain tumor. The present study examined the relationship between biophysical and physical dose metrics and neurocognitive ability, namely learning and memory, 2 years post-RT in pediatric brain tumor patients.

PROCEDURE

The sample consisted of 26 pediatric patients with brain tumor, 14 of whom completed neuropsychological evaluations on average 24 months post-RT. Prescribed dose and dose-volume metrics for specific brain regions were calculated including physical metrics (i.e., mean dose and maximum dose) and biophysical metrics (i.e., integral biological effective dose and generalized equivalent uniform dose). We examined the associations between dose-volume metrics (whole brain, right and left hippocampus), and performance on measures of learning and memory (Children's Memory Scale).

RESULTS

Biophysical dose metrics were highly correlated with the physical metric of mean dose but not with prescribed dose. Biophysical metrics and mean dose, but not prescribed dose, correlated with measures of learning and memory.

CONCLUSIONS

These preliminary findings call into question the value of prescribed dose for characterizing treatment intensity; they also suggest that biophysical dose has only a limited advantage compared to physical dose when calculated for specific regions of the brain. We discuss the implications of the findings for evaluating and understanding the relation between RT and neurocognitive functioning.

Processing speed in children treated for brain tumors: effects of radiation therapy and age

The current study examined processing speed in children two years post-treatment for brain tumors (BT) with radiation therapy (RT) compared to those treated with without RT. Participants included 59 children (4-17 years) with BT assessed as part of the Brain Radiation Investigative Study Consortium (BRISC). Processing speed was assessed at two time points: Time1 (3-9 months post-surgery) for 26 children who received whole brain or focal RT (RT group) and 33 treated without RT (no-RT group), and again two years later (Time2) for 42 participants (17 RT, 25 no-RT). Linear mixed effects (LME) regression analyses examined differences in cognitive and motor speed between groups and across visits, with age at Time1 (age1) treated as a moderating variable, and sex and primary tumor size as covariates. No effects for treatment group or visit were found for motor speed (Pegboard) or mean reaction time (Attention Network Task). On the Wechsler Processing Speed Index (PSI), the no-RT group performed better than the RT group, with a group-by-age interaction such that across visits, the difference between the no-RT and RT groups was larger among children who were older at initial treatment (≥10 years) than among those who were younger (<10 years). Cumulative brain injury earlier in life (tumor, surgery, plus RT) may result in greater impact on more complex tasks of cognitive efficiency. Children receiving RT showed reduced processing speed over time, with a larger group difference among those who were over 10 years at treatment.

Long-term effects of radiation therapy on white matter of the corpus callosum: a diffusion tensor imaging study in children

BACKGROUND

Despite improving survival rates, children are at risk for long-term cognitive and behavioral difficulties following the diagnosis and treatment of a brain tumor. Surgery, chemotherapy and radiation therapy have all been shown to impact the developing brain, especially the white matter.

OBJECTIVE

The purpose of this study was to determine the long-term effects of radiation therapy on white matter integrity, as measured by diffusion tensor imaging, in pediatric brain tumor patients 2 years after the end of radiation treatment, while controlling for surgical interventions.

MATERIALS AND METHODS

We evaluated diffusion tensor imaging performed at two time points: a baseline 3 to 12 months after surgery and a follow-up approximately 2 years later in pediatric brain tumor patients. A region of interest analysis was performed within three regions of the corpus callosum. Diffusion tensor metrics were determined for participants (n=22) who underwent surgical tumor resection and radiation therapy and demographically matched with participants (n=22) who received surgical tumor resection only.

RESULTS

Analysis revealed that 2 years after treatment, the radiation treated group exhibited significantly lower fractional anisotropy and significantly higher radial diffusivity within the body of the corpus callosum compared to the group that did not receive radiation.

CONCLUSION

The findings indicate that pediatric brain tumor patients treated with radiation therapy may be at greater risk of experiencing long-term damage to the body of the corpus callosum than those treated with surgery alone.

[Formula: see text]Working memory and attention in pediatric brain tumor patients treated with and without radiation therapy

Children are at risk for cognitive difficulties following the diagnosis and treatment of a brain tumor. Longitudinal studies have consistently demonstrated declines on measures of intellectual functioning, and recently it has been proposed that specific neurocognitive processes underlie these changes, including working memory, processing speed, and attention. However, a fine-grained examination of the affected neurocognitive processes is required to inform intervention efforts. Radiation therapy (RT) impacts white matter integrity, likely affecting those cognitive processes supported by distributed neural networks. This study examined working memory and attention in children during the early delayed stages of recovery following surgical resection and RT. The participants included 27 children diagnosed with pediatric brain tumor, treated with (n = 12) or without (n = 15) RT, who completed experimental and standardized measures of working memory and attention (n-back and digit span tasks). Children treated with radiation performed less well than those who did not receive radiation on the n-back measure, though performance at the 0-back level was considerably poorer than would be expected for both groups, perhaps suggesting difficulties with more basic processes such as vigilance. Along these lines, marginal differences were noted on digit span forward. The findings are discussed with respect to models of attention and working memory, and the interplay between the two.

Attention, processing speed, and executive functioning in pediatric brain tumor survivors treated with proton beam radiation therapy

BACKGROUND AND PURPOSE

This study examines attention, processing speed, and executive functioning in pediatric brain tumor survivors treated with proton beam radiation therapy (PBRT).

MATERIAL AND METHODS

We examined 39 survivors (age 6-19years) who were 3.61years post-PBRT on average. Craniospinal (CSI; n=21) and focal (n=18) subgroups were analyzed. Attention, processing speed, and executive functioning scores were compared to population norms, and clinical/demographic risk factors were examined.

RESULTS

As a group, survivors treated with focal PBRT exhibited attention, processing speed, and executive functioning that did not differ from population norms (all p>0.05). Performance in the CSI group across attention scales was normative (all p>0.05), but areas of relative weakness were identified on one executive functioning subtest and several processing speed subtests (all p<0.01).

CONCLUSIONS

Survivors treated with PBRT may exhibit relative resilience in cognitive domains traditionally associated with radiation late effects. Attention, processing speed, and executive functioning remained intact and within normal limits for survivors treated with focal PBRT. Among survivors treated with CSI, a score pattern emerged that was suggestive of difficulties in underlying component skills (i.e., processing speed) rather than true executive dysfunction. No evidence of profound cognitive impairment was found in either group.

Measurement of neurodevelopmental changes in children treated with radiation for brain tumors: what is a true 'baseline?'

OBJECTIVE

To review the various ways in which baseline neuropsychological functioning is measured in the extant literature on pediatric brain tumors, describe the pros and cons of each approach, and increase the awareness of researchers as to the implications of each.

METHOD

We reviewed the literature from 1993 to 2013, and classified studies by baseline approach and explicitness of selection of approach.

RESULTS

There are multiple approaches to operationalizing baseline levels of ability and to assess change from baseline. Each approach has strengths and weaknesses, and selection may depend on the question under investigation. Approaches to baseline estimation varied widely with a trend over time toward reliance on statistical modeling. Researchers were often insufficiently explicit about the reasons for adopting a particular approach. The common use of standardized scores requires caution as they obscure critical inferential limitations about change and magnitude of change. Some viable approaches were infrequently used, such as actuarial prediction formulas. Multiple simultaneous methods akin to theory testing and formal methods of construct validation could enhance scientific yield since all approaches are fallible.

CONCLUSIONS

Estimating baseline neuropsychological functioning is very challenging, particularly when it concerns children in the preschool years. Nevertheless, it is a crucial methodological decision with important implications for the interpretation of research findings that needs to be dealt with explicitly.

Utility of the General Ability Index (GAI) and Cognitive Proficiency Index (CPI) with survivors of pediatric brain tumors: Comparison to Full Scale IQ and premorbid IQ estimates

INTRODUCTION

Pediatric brain tumor survivors are at risk for working memory and processing speed impairment. The General Ability Index (GAI) provides an estimate of intellectual functioning that is less influenced by working memory and processing speed than a Full Scale IQ (FSIQ). The Cognitive Proficiency Index (CPI) provides a measure of efficient information processing derived from working memory and processing speed tasks. We examined the utility of the GAI and CPI to quantify neurocognitive outcomes in a sample of pediatric brain tumor survivors.

METHOD

GAI, CPI, and FSIQ scores from the Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV) were examined for 57 pediatric brain tumor survivors (ages 6-16 years) treated with cranial radiation therapy (RT).

RESULTS

GAI scores were higher than FSIQ and CPI scores, both p < .001. Lower CPI scores were associated with history of craniospinal irradiation and time since RT. Lower FSIQ and GAI scores were associated with higher RT dose and time since RT. The rate of clinically significant GAI-FSIQ discrepancies in our sample was greater than that observed in the WISC-IV standardization sample, p < .001. Estimated premorbid IQ scores were higher than GAI, p < .01, and FSIQ scores, p < .001.

CONCLUSIONS

Pediatric brain tumor survivors exhibit weaker cognitive proficiency than that expected for age, while general reasoning ability remains relatively spared. The GAI may be useful to quantify the intellectual potential of a survivor when appropriate accommodations are in place for relative cognitive proficiency weaknesses. The CPI may be a particularly sensitive outcome measure of treatment-related cognitive change in this population.

Comparing Intelligence Quotient Change After Treatment With Proton Versus Photon Radiation Therapy for Pediatric Brain Tumors

PURPOSE

Compared with photon radiation (XRT), proton beam radiation therapy (PBRT) reduces dose to normal tissues, which may lead to better neurocognitive outcomes. We compared change in intelligence quotient (IQ) over time in pediatric patients with brain tumors treated with PBRT versus XRT.

PATIENTS AND METHODS

IQ scores were available for 150 patients (60 had received XRT, 90 had received PBRT). Linear mixed models examined change in IQ over time since radiation therapy (RT) by RT group, controlling for demographic/clinical characteristics. Craniospinal and focal RT subgroups were also examined.

RESULTS

In the PBRT group, no change in IQ over time was identified (P = .130), whereas in the XRT group, IQ declined by 1.1 points per year (P = .004). IQ slopes did not differ between groups (P = .509). IQ was lower in the XRT group (by 8.7 points) versus the PBRT group (P = .011). In the craniospinal subgroup, IQ remained stable in both the PBRT (P = .203) and XRT groups (P = .060), and IQ slopes did not differ (P = .890). IQ was lower in the XRT group (by 12.5 points) versus the PBRT group (P = .004). In the focal subgroup, IQ scores remained stable in the PBRT group (P = .401) but declined significantly in the XRT group by 1.57 points per year (P = .026). IQ slopes did not differ between groups (P = .342).

CONCLUSION

PBRT was not associated with IQ decline or impairment, yet IQ slopes did not differ between the PBRT and XRT groups. It remains unclear if PBRT results in clinically meaningful cognitive sparing that significantly exceeds that of modern XRT protocols. Additional long-term data are needed to fully understand the neurocognitive impact of PBRT in survivors of pediatric brain tumors.

Predictors of adaptive functioning and psychosocial adjustment in children with pediatric brain tumor: a report from the Brain Radiation Investigative Study Consortium

BACKGROUND

Children are at risk for psychosocial and adaptive morbidities following diagnosis of and treatment for a pediatric brain tumor. This study examined whether familial/demographic, developmental, diagnostic, or treatment-related variables best predict the acute psychosocial adjustment and adaptive functioning of children soon after an initial diagnosis.

PROCEDURE

Participants included 56 children (mean age = 10.72, SD = 4.02) newly diagnosed with a pediatric brain tumor. Parents completed background/demographic forms and completed ratings of children's behavioral and emotional symptoms, and adaptive behavior. Diagnostic and treatment-related information was abstracted from medical records.

RESULTS

Parent ratings of behavioral symptoms and adaptive functioning were within normative expectation, although rates of clinical impairment in adaptive functioning exceeded expected rates. A combination of familial/demographic and diagnostic variables were associated with acute functioning. In multiple regressions, tumor size best predicted adaptive functioning after initial diagnosis, whereas tumor location best predicted variance in behavioral symptoms.

CONCLUSIONS

Children may be more vulnerable to acute impairment in adaptive functioning following diagnosis of a pediatric brain tumor, but rates of behavioral symptoms were within expectation. Familial, sociodemographic, and diagnostic variables may help to identify those most at risk of impairment. Screening of these factors within tertiary care settings will be useful to identify those most in need of psychosocial care during the initial phases of treatment.

Oxandrolone for the treatment of bone marrow failure in Fanconi anemia

BACKGROUND

A majority of Fanconi anemia (FA) patients will experience bone marrow failure (BMF) and androgen therapy (most often oxymetholone) may be utilized as a treatment to improve BMF-related cytopenias. However, oxymetholone is associated with toxicities making identification of other agents of interest. In this study we aimed to evaluate the toxicity profile and hematologic response in patients with FA who are treated with low-dose oxandrolone, a synthetic non-fluorinated anabolic steroid, similar to oxymetholone, with known dosing thresholds for virilization.

PROCEDURE

A single arm, Phase I/II study was designed to treat patients on low-dose oxandrolone. If no toxicity or hematologic response was noted at 16 weeks, a single dose escalation was offered. Subjects were regularly assessed for toxicity, including determinations of virilization, behavioral changes, and liver and kidney function. At 32 weeks, those who demonstrated hematologic response were allowed to continue study treatment, and those without improvement were deemed non-responsive.

RESULTS

Nine subjects completed the study and were followed for a median of 99 weeks (46-136 weeks). Three (33.3%) subjects developed mild sub-clinical virilization and continued treatment with a dose reduction. None (0%) had adverse behavioral changes. Two (22.2%) developed elevated liver function tests at 42 and 105 weeks. Seven (77.8%) subjects had a hematologic response.

CONCLUSION

Oxandrolone appears to be well-tolerated, has limited toxicities at the administered doses in FA with patients, and may be an alternative androgen for the treatment of BMF in FA.

Intellectual and academic outcome following two chemotherapy regimens and radiotherapy for average-risk medulloblastoma: COG A9961

PURPOSE

Assess the intellectual and academic outcomes as well as risk factors associated with treatment for average-risk medulloblastoma in childhood using 23.4 Gy of craniospinal radiotherapy plus adjuvant chemotherapy.

METHODS

From an overall sample of 379 enrolled in the parent study (COG A9961), 110 patients received a total of 192 assessments over more than 5 years with standardized IQ and academic achievement tests. Random coefficient models of the various outcomes were developed that incorporated covariates including chemotherapy regimen, age at diagnosis, sex, initial Full Scale IQ, and mutism.

RESULTS

Participants in this study were found to be comparable to the overall sample in all demographic, disease, and treatment factors, except there were more gross total resections in the subsample undergoing intellectual and academic assessment. Major findings include significant decline in both intellectual and academic domains over time that were greater in children who were younger at diagnosis and had higher initial intelligence test scores. Children with mutism were at higher risk for initial effects on intelligence. No effects of sex were found.

CONCLUSION

These results show progressive decline over several years post-treatment in standardized intellectual and academic scores. Despite recent improvements in therapies for these children, most notably a decrease dose of craniospinal radiation, they remain at risk. The pursuit of less toxic treatments, particularly for younger children, should continue. Neuropsychological surveillance should be routine at centers treating children with brain tumors.

IQ change within three years of radiation therapy in pediatric brain tumor patients treated with proton beam radiation therapy versus photon radiation therapy

10009

Background: Radiation therapy (RT), an essential treatment for pediatric brain tumors, increases the risk of cognitive impairment. Advanced RT techniques reduce the volume of normal tissues receiving radiation dose. Proton beam radiation therapy (PBRT) minimizes irradiation to surrounding healthy brain tissue, with the potential to preserve cognitive function better than photon radiotherapy (XRT). We examined change in IQ over time between patients treated for pediatric brain tumors with PBRT versus XRT. Methods: IQ scores obtained in the first 3 years post-RT were abstracted for pediatric brain tumor patients treated with PBRT or XRT. Results: Baseline and follow-up IQ scores were available for 53 survivors (31 PBRT, 22 CRT). A linear regression model predicted follow-up IQ scores controlling for baseline IQ, age-at-RT, time-since-RT, and craniospinal irradiation (CSI), F(7,45)=23.4, p<.001. Follow-up IQ scores were significantly lower in the XRT group compared to the PBRT group (p<.05). The XRT group lost 10.3 IQ points on average with each additional year post-RT (p<.01), while the PBRT group remained stable, losing only 0.1 points per year on average (p<.05). CSI was associated with IQ decline in both groups (p<.05), while age-at-RT was not in either group (p=.154). Total RT dose was not associated with IQ with the above variables in the model. Conclusions: Findings suggest significant cognitive risk is associated with XRT, with IQ scores declining by more than half a standard deviation with each additional year post-RT. In contrast, IQ remained stable in the PBRT group. Preliminary findings suggest that PBRT may spare cognitive functioning in the first 3 years post-RT. Future research should replicate these findings with a larger sample and should study longer-term cognitive outcomes in patients treated with PBRT versus XRT. [Table: see text]

Neuropsychological late effects and rehabilitation following pediatric brain tumor

The modern era of research into the neurobehavioral late effects of pediatric brain tumor has been one of refinement in outcome measurement and advances in identification of risk factors for neurobehavioral impairment. There is no neuropsychological phenotype that encompasses all tumor types, treatments, and risk factors, though attention, working memory, processing speed, new learning, visuospatial and visuomotor functioning, executive functioning, and areas of academic achievement have been found to be at particular risk. Additional socioemotional and broader quality of life problems have been found in both survivors and their families. Past research has identified neuropsychological risk factors that include tumor location, radiation therapy and dose, certain chemotherapy agents, neurological complications, and demographic factors such as young age and female gender. Recent refinement in measurement of risk is improving our prediction of neurobehavioral outcomes. Neuropsychological and psychosocial interventions are now being developed, and the evidence base supporting these interventions is growing. Simultaneous advances in each of these areas will facilitate translation of research into risk-adapted rehabilitative care such that resources can be most effectively re-allocated and the best possible outcomes achieved.

The association between sleep disordered breathing, academic grades, and cognitive and behavioral functioning among overweight subjects during middle to late childhood

STUDY OBJECTIVES

(1) to determine the associations of sleep disordered breathing (SDB) with behavioral functioning, cognitive test scores, and school grades during middle- to late-childhood, an under-researched developmental period in the SDB literature, and (2) to clarify whether associations between SDB and school grades are mediated by deficits in cognitive or behavioral functioning.

DESIGN

cross-sectional correlative study.

SETTING

Office/hospital, plus reported functioning at home and at school.

PARTICIPANTS

163 overweight subjects aged 10-16.9 years were divided into 4 groups based upon their obstructive apnea+hypopnea index (AHI) during overnight polysomnography and parent report of snoring: Moderate-Severe OSA (AHI > 5, n = 42), Mild OSA (AHI = 1-5, n = 58), Snorers (AHI < 1 + snoring, n = 26), and No SDB (AHI < 1 and nonsnoring, n = 37).

MEASUREMENTS

inpatient overnight polysomnography, parent- and self-report of school grades and sleep, parent- and teacher-report of daytime behaviors, and office-based neuropsychological testing.

RESULTS

The 4 groups significantly differed in academic grades and parent- and teacher-reported behaviors, particularly inattention and learning problems. These findings remained significant after adjusting for subject sex, race, socioeconomic status, and school night sleep duration. Associations with SDB were confined to reports of behavioral difficulties in real-world situations, and did not extend to office-based neuropsychological tests. Findings from secondary analyses were consistent with, but could not definitively confirm, a causal model in which SDB affects school grades via its impact on behavioral functioning.

CONCLUSIONS

SDB during middle- to late-childhood is related to important aspects of behavioral functioning, especially inattention and learning difficulties, that may result in significant functional impairment at school.

Cognitive and adaptive outcome in extracerebellar low-grade brain tumors in children: a report from the Children's Oncology Group

PURPOSE

To determine whether pediatric patients treated with surgery only for low-grade tumors in the cerebral hemispheres, supratentorial midline, and exophytic brainstem evidence neurocognitive, academic, adaptive, or emotional/behavioral sequelae.

PATIENTS AND METHODS

Ninety-three patients from a natural history study of low-grade astrocytomas were tested an average of 111 days after surgery. Rates of below average (< or = 25th percentile) scores in this sample were compared with test norms, and performances were compared across anatomic sites. Finally, the relationships of pre-, peri-, and postsurgical complications to outcome were investigated.

RESULTS

For the entire sample, there was a significantly elevated rate of below average scores across intelligence quotient, achievement, and adaptive behavior, but not behavioral/emotional adjustment measures. Patients with hemispheric, midline, and brainstem tumors did not differ significantly. Patients with left hemisphere tumors generally performed worse than those with right hemisphere tumors. Finally, neurobehavioral outcome was unrelated to pre-, peri-, or postsurgery complications.

CONCLUSION

After surgery for low-grade brain tumors, a significant number of patients was found to function below average, by as much as 55% compared with 25% in the normative population. Moreover, these results suggest greater risk for patients with lesions situated in the left cerebral hemisphere. Routine neuropsychological follow-up of children after treatment for low-grade tumors is recommended.

Factors of biological risk and reserve associated with executive behaviors in children and adolescents with spina bifida myelomeningocele

This study examined differences between healthy children (n = 35) and those with spina bifida myelomeningocele (SBM; n = 42) on the Behavior Rating Inventory of Executive Function (BRIEF), a measure of executive function behaviors. It also examined whether aspects of biological risk associated with SBM and reserve factors within the family could account for variability in BRIEF scores for children and adolescents with SBM. Patients in the SBM group exhibited more problems than both published norms and a local comparison group of healthy children in metacognition but not behavior regulation. Behavior regulation problems in children with SBM were predicted by parent psychological distress. More shunt-related surgeries and history of seizures predicted poorer metacognitive abilities.

Association of prenatal and childhood blood lead concentrations with criminal arrests in early adulthood

BACKGROUND

Childhood lead exposure is a purported risk factor for antisocial behavior, but prior studies either relied on indirect measures of exposure or did not follow participants into adulthood to examine the relationship between lead exposure and criminal activity in young adults. The objective of this study was to determine if prenatal and childhood blood lead concentrations are associated with arrests for criminal offenses.

METHODS AND FINDINGS

Pregnant women were recruited from four prenatal clinics in Cincinnati, Ohio if they resided in areas of the city with a high concentration of older, lead-contaminated housing. We studied 250 individuals, 19 to 24 y of age, out of 376 children who were recruited at birth between 1979 and 1984. Prenatal maternal blood lead concentrations were measured during the first or early second trimester of pregnancy. Childhood blood lead concentrations were measured on a quarterly and biannual basis through 6.5 y. Study participants were examined at an inner-city pediatric clinic and the Cincinnati Children's Hospital Medical Center in Cincinnati, Ohio. Total arrests and arrests for offenses involving violence were collected from official Hamilton County, Ohio criminal justice records. Main outcomes were the covariate-adjusted rate ratios (RR) for total arrests and arrests for violent crimes associated with each 5 microg/dl (0.24 micromol/l) increase in blood lead concentration. Adjusted total arrest rates were greater for each 5 microg/dl (0.24 micromol/l) increase in blood lead concentration: RR = 1.40 (95% confidence interval [CI] 1.07-1.85) for prenatal blood lead, 1.07 (95% CI 0.88-1.29) for average childhood blood lead, and 1.27 (95% CI 1.03-1.57) for 6-year blood lead. Adjusted arrest rates for violent crimes were also greater for each 5 microg/dl increase in blood lead: RR = 1.34 (95% CI 0.88-2.03) for prenatal blood lead, 1.30 (95% CI 1.03-1.64) for average childhood blood lead, and 1.48 (95% CI 1.15-1.89) for 6-year blood lead.

CONCLUSIONS

Prenatal and postnatal blood lead concentrations are associated with higher rates of total arrests and/or arrests for offenses involving violence. This is the first prospective study to demonstrate an association between developmental exposure to lead and adult criminal behavior.

Functional magnetic resonance imaging assessment of cognitive function in childhood-onset systemic lupus erythematosus: a pilot study

OBJECTIVE

To investigate changes in brain activation patterns detected by functional magnetic resonance imaging (FMRI), and the relationship between FMRI activation patterns and results of formal neuropsychological testing, in patients with childhood-onset systemic lupus erythematosus (SLE).

METHODS

Ten patients with childhood-onset SLE underwent formal neuropsychological testing and FMRI using 3 paradigms: a continuous performance task (CPT) to evaluate attention, an N-Back task to assess working memory, and verb generation to evaluate language processing. Composite Z maps were generated to summarize the brain activation patterns for each FMRI paradigm in patients with childhood-onset SLE and to compare these patterns with those observed in healthy controls. Between-group comparison Z maps showing differences in activation between childhood-onset SLE patients and controls were generated, using a significance level of P < 0.05 in a general linear model.

RESULTS

Compared with the control group, the childhood-onset SLE group showed statistically significant increased activation of brain areas involved in the CPT, N-Back, and verb generation tasks. In contrast, in the absence of active stimulus, e.g., during times of the paradigm control tasks, childhood-onset SLE patients consistently undersuppressed activity in the expected brain areas. Activation in selected cortical areas was found to correlate negatively with results of a subset of individual neuropsychological test scores.

CONCLUSION

FMRI abnormalities are present in childhood-onset SLE, manifesting as an imbalance between active and inhibitory responses to an array of stimuli. Differences in brain activation patterns compared with those observed in controls suggest that childhood-onset SLE may be associated with abnormalities in white matter connectivity resulting in neuronal network dysfunction, rather than injury of specific gray matter areas.

Lessons in pediatric neuropsycho-oncology: what we have learned since Johnny Gunther

OBJECTIVE

This article provides a commentary on the progression of research over the last six decades into the neurobehavioral outcomes of children treated for intracranial tumors.

METHODS

Published studies and literature reviews are surveyed, with illustrations from the author's ongoing longitudinal study.

RESULTS

Research on late effects in pediatric brain tumors continues to increase in both volume and quality. Samples are larger and more differentiated, scope of outcome measurement has increased, and more powerful developmental research designs are being used. Particularly promising recent developments are described, including research on: imaging-behavior relationships, improved modeling of dose-volume heterogeneity in radiation therapy, improved late effects measurement, and treatments for neurobehavioral sequelae.

CONCLUSIONS

There is now a large body of scientific evidence of increasing sophistication regarding the outcomes of patients receiving the most toxic treatments. It is argued that more research into the neuropsychological effects associated with "benign" tumors of childhood is needed.

Taxonicity of nonverbal learning disabilities in spina bifida

As currently defined, it is not clear whether Nonverbal Learning Disabilities (NLD) should be considered a matter of kind or magnitude (Meehl, 1995). The taxonicity of NLD, or the degree to which it is best construed as discrete versus continuous, has not been investigated using methods devised for this purpose. Latent Class Analysis (LCA) is a method for finding subtypes of latent classes from multivariate categorical data. This study represents an application of LCA on a sample of children and adolescents with spina bifida myelomeningocele (SBM) (N = 44), those presenting with features of NLD (N = 28) but no medical condition, and control volunteers (N = 44). The two-class solution provided evidence for the presence of a taxon with an estimated base-rate in the SBM group of .57. Indicator validities (the conditional probabilities of indicator endorsement in each latent class) suggest a somewhat different priority for defining NLD than is typically used by researchers investigating this disorder. A high degree of correspondence between LCA classifications and those based on a more conventional algorithm provided evidence for the validity of this approach.

The impact of early childhood lead exposure on brain organization: a functional magnetic resonance imaging study of language function

OBJECTIVES

The purpose of this work was to assess the long-term impact of childhood lead exposure on the neurosubstrate of language function and brain organization.

METHODS

Young adults from the Cincinnati Lead Study were recruited to undergo functional magnetic resonance image scanning while performing a verb generation task. These subjects have been followed from birth through early childhood with extensive documentation of lead exposure, neuropsychology, and behavior. Forty-two subjects provided useful imaging data. The locale, strength, and the correlation between brain language activation and childhood blood lead concentration were studied.

RESULTS

After adjusting for potential confounders, the activation in left frontal cortex, adjacent to Broca's area, and left middle temporal gyrus, including Wernicke's area, were found to be significantly associated with diminished activation in subjects with higher mean childhood blood lead levels, whereas the compensatory activation in the right hemisphere homolog of Wernicke's area was enhanced in subjects with higher blood lead levels.

CONCLUSION

This study indicates that childhood lead exposure has a significant and persistent impact on brain reorganization associated with language function.

Cognitive and adaptive outcome in low-grade pediatric cerebellar astrocytomas: evidence of diminished cognitive and adaptive functioning in National Collaborative Research Studies (CCG 9891/POG 9130)

PURPOSE

Clinicians often assume that children with posterior fossa tumors are at minimal risk for cognitive or adaptive deficits if they do not undergo cranial irradiation. However, small case series have called that assumption into question, and have also suggested that nonirradiated cerebellar tumors can cause location-specific cognitive and adaptive impairment. This study (1) assessed whether resected but not irradiated pediatric cerebellar tumors are associated with cognitive and adaptive functioning deficits, and (2) examined the effect of tumor location and medical complications on cognitive and adaptive functioning.

PATIENTS AND METHODS

The sample was composed of 103 children aged 3 to 18 years with low-grade cerebellar astrocytomas, who underwent only surgical treatment as part of Children's Cancer Group protocol 9891 or Pediatric Oncology Group protocol 9130. The sample was divided into three groups based on primary tumor location: vermis, left hemisphere, or right hemisphere. Data were collected prospectively on intelligence, academic achievement, adaptive skills, behavioral functioning, and pre-, peri-, and postsurgical medical complications.

RESULTS

The sample as a whole displayed an elevated risk for cognitive and adaptive impairment that was not associated consistently with medical complications. Within this group of children with cerebellar tumors, tumor location had little effect on cognitive, adaptive, or medical outcome.

CONCLUSION

We did not replicate previous findings of location-specific effects on cognitive or adaptive outcome. However, the elevated risk of deficits in this population runs contrary to clinical lore, and suggests that clinicians should attend to the functional outcomes of children who undergo only surgical treatment for cerebellar tumors.

Melatonin treatment of pediatric residents for adaptation to night shift work

BACKGROUND

Night float rotations are used in residency training programs to reduce residents' sleep deprivation. Night shift work, however, is accompanied by deleterious effects on sleep, mood, and attention.

OBJECTIVE

To test whether melatonin reduces the deleterious effects of night shift work on sleep, mood, and attention in pediatric residents during night float rotation.

DESIGN/METHODS

Double-blind, randomized, placebo-controlled crossover. Participants took melatonin (3 mg) or a placebo before bedtime in the morning after night shift; completed a sleep diary and an adverse-effects questionnaire daily; and completed the Profile of Mood States and the Conners Continuous Performance Test 3 times in each study week to test mood and attention, respectively.

SETTING

A university-affiliated, tertiary-care pediatric hospital.

PARTICIPANTS

Healthy second-year pediatric residents working 2 night float rotations.

OUTCOME MEASURES

Standardized measures of sleep, mood, and attention.

RESULTS

Twenty-eight residents completed both treatments; 17 completed 1 treatment (10 placebo, 7 melatonin). There was not a statistically significant difference in measures of sleep, mood, and 5 of 6 measures of attention during melatonin and placebo treatment. One measure of attention, the number of omission errors, was significantly lower on melatonin (3.0 +/- 9.6) than on placebo (4.5 +/- 17.5) (z = -2.12, P = .03).

CONCLUSIONS

The isolated finding of improvement of 1 single measure of attention in a test situation during melatonin treatment was not sufficiently robust to demonstrate a beneficial effect of melatonin in the dose used. Other strategies need to be considered to help residents in adaptation to night shift work.

An improved methodology for modeling neurobehavioral late-effects of radiotherapy in pediatric brain tumors

BACKGROUND

Technical advances in radiation oncology provide new opportunities to study neurobehavioral outcomes of radiation therapy (RT) in children treated for brain tumors.

METHODS

In this study, we describe an approach to modeling late-effects using integral biologically effective dose (IBED) combined with improved measurement of critical neuropsychological functions.

RESULTS

IBED was found to provide more differentiated information about dose distribution than prescribed dose in five subjects treated for brain tumors. Furthermore, IBED was more closely related than was prescribed dose to specific changes in Attention 2-3 years post-RT.

CONCLUSIONS

Results support the feasibility of this methodology as well as promising preliminary evidence of the relationship of IBED to the construct of Attention. Improved modeling could lead to more refined radiation therapy protocols that preserve critical neuropsychological functions and also provide new insights into the treatment of neurobehavioral sequelae.

Board certification in clinical neuropsychology: a response to Rohling et al

Board certification is intended to protect the public by identifying practitioners that have met minimum standards for education and training in their specialty or discipline. For varied reasons, clinical neuropsychology, like professional psychology as a whole, has struggled to achieve levels of board certification comparable to the medical profession. Rohling, Lees-Haley, Langhinrichsen-Rohling, & Williamson (2003) have recently published a critique of the board certification process in clinical neuropsychology as it is conducted by American Board of Clinical Neuropsychology (ABCN), arguing that one reason for this failure is the overly restrictive nature of the process. In their paper, Rohling et al. provide a signal detection analysis that makes several assumptions about the process and conclude with recommendations for improving the process to better identify "competent" neuropsychologists in practice. While we agree in principle with many of their recommendations, and ABCN had, in fact, implemented several prior to publication of their article, the article contains many faulty assumptions and logical inconsistencies that we believe are harmful to constructive review of the certification process. In this article, we provide a critical review of their analysis and present new and additional data that demonstrate the procedure is not overly restrictive. A primary consideration is the low incidence of seeking board certification among professionals who identify themselves as neuropsychologists (i.e., a low application rate), rather than an overly restrictive process. We describe steps taken to improve the process and conclude that there are numerous areas of agreement with Rohling et al., including the need for ongoing review and continued improvement in the board certification process in all psychological specialties.

Relationship of structural magnetic resonance imaging, magnetic resonance perfusion, and other disease factors to neuropsychological outcome in sickle cell disease

OBJECTIVE

To investigate the relationship between neuropsychological functioning and radiographic findings in children with sickle cell disease (SCD) with no history of clinical neurological events.

METHODS

Thirty-one patients with SCD randomly selected from a regional treatment center underwent neuropsychological and disease severity assessments. Of these, 22 also had structural magnetic resonance imaging and magnetic resonance perfusion studies performed.

RESULTS

Forty-five percent of the imaged subgroup showed imaging abnormalities that were found to be correlated with disease severity but not neuropsychological level of performance indices. A significant relationship, however, was found between imaging abnormalities and increased variability in neuropsychological performance.

CONCLUSIONS

These results corroborate the high rate of rheologic and vascular pathology in SCD and underscore the importance of representing neuropsychological functioning in multiple ways.

Executive Functioning and Memory for the Rey-Osterreith Complex Figure Task Among Community Adolescents

Although there is empirical support for the link between executive functioning (EF) and visual memory among adults, there has been less exploration of this link among children, especially adolescents. We examined the relation between several EF measures and performance on the Rey-Osterrieth Complex Figure (RCF) in a sample of 160 community adolescents. Each was administered the Wisconsin Card Sorting Test (WCST), Conners Continuous Performance Test (CPT), and the RCF, scored using Bernstein and Waber's (1996) Developmental Scoring System (DSS). Ability to organize the RCF related to memory encoding/retrieval, but not to long-term storage. Indexes derived from the WCST and CPT failed to correlate with any RCF index, raising questions about the relation between DSS scores and EF. Even so, data supported the convergent validity of the DSS system as a reflection of visual-constructional ability and provided evidence of the importance of organizational strategies to visual memory among adolescents.

Early exposure to lead and neuropsychological outcome in adolescence

One hundred and ninety-five participants in the Cincinnati Lead Study were neuropsychologically evaluated in mid-adolescence. The neuropsychological measures yielded five factors labeled Memory, Learning/IQ, Attention, Visuoconstruction, and Fine-Motor. Prenatal, Average Childhood, and 78 month blood lead (PbB) levels were used in a series of multiple regression analyses. Following rigorous covariate pretesting and adjustment, a significant main effect of 78 month PbB on the Fine-Motor factor was found (p <.004). Significant interactions were also found between gender and lead exposure parameters for both Attention and Visuoconstruction indicating heightened risk in males. Finally, a trend toward significance was found for the PbB x SES interaction for Learning/IQ, consistent with previous evidence of increased educational and cognitive vulnerability for youth from more disadvantaged backgrounds. These results provide new evidence from the longest continuing prospective study of the remote effects of early lead exposure. They indicate the presence of selective neuropsychological effects in this population, and also that males and females are not uniformly affected. These results also underscore the complexity of models of neurobehavioral development, and the modest predictive power of any single determinant.