Function-specific neuropsychological assessment

Neuropsychological differences between survivors of supratentorial and infratentorial brain tumours

BACKGROUND

The purpose of this study is to evaluate the relationship between brain tumour location and core areas of cognitive and behavioural functioning for paediatric brain tumour survivors. The extant literature both supports and refutes an association between paediatric brain tumour location and neurocognitive outcomes. We examined neuropsychological test data to identify any differences in neurocognitive and behavioural profile associated with supratentorial versus infratentorial tumour location.

METHODS

Following Institutional Review Board approval, the medical records and neuropsychological test data collected between 1997 and 2002 for 70 children treated for brain tumour at Children's Hospital Los Angeles were reviewed. Fifty-one per cent of the participants had tumours located in the supratentorial regions of the brain, whereas 49% had infratentorial tumours. Primary medical treatments involved tumour resection (90%), cranial radiation therapy (76%), chemotherapy (71%), and 59% all three medical procedures. The two tumour location groups did not differ significantly in the cumulative treatment dose of irradiation to the tumour bed or in the dose delivered to the whole brain. Neuropsychological test data included measures of verbal and non-verbal intellectual functioning, attention/working memory, processing speed, verbal and visual memory, fine motor skills, visual-motor integration, academic achievement, and social-emotional functioning. Differences between the two groups were evaluated using anova, t-tests and chi-squared statistical tests.

RESULTS

The supratentorial and infratentorial tumour location groups did not differ on measures of intellectual functioning. However, survivors of infratentorial tumours performed more poorly on selected measures of more specific cognitive functions and on parent-report of social-emotional functioning relative to survivors of supratentorial tumours, even when age at diagnosis was held as a covariate. Higher frequency of auditory deficits was noted in the infratentorial tumour group and was associated with lowered academic achievement scores.

CONCLUSIONS

The differences by location found in more specific neurocognitive and social-emotional variables, after controlling for age at diagnosis, may possibly reflect tumour location-specific effects. However, this interpretation remains tentative given the limitations in our study and inability to control for the range of medical and treatment-related factors that may have contributed towards the outcomes observed in our sample. At the same time, most of our findings appear consistent with reports from recent studies in this area.

Reliability and validity of the Childhood Cancer Survivor Study Neurocognitive Questionnaire

BACKGROUND

Up to 40% of childhood cancer survivors may experience neurocognitive impairment in 1 or more specific domains. As such, regular monitoring has been recommended for patients exposed to cranial irradiation and/or antimetabolite chemotherapy. This study reports the results of a questionnaire developed to identify those survivors who may be experiencing neurocognitive problems.

METHODS

Participants for this study were 7121 members of the Childhood Cancer Survivor Study cohort (6739 survivors and 382 siblings). These participants completed a new neurocognitive questionnaire designed to assess functions commonly affected by cancer therapy, as well as a standard measure of emotional functioning. A measure of cognitive and emotional functioning was also completed on a subset of the patients roughly 7 years before the current questionnaire. Responses to the questionnaires among subgroups of survivors were then analyzed to examine the reliability and validity of the new neurocognitive questionnaire.

RESULTS

Four reliable factors were identified that assessed task efficiency, emotional regulation, organization, and memory skills. These neurocognitive factors accurately discriminated survivors who were at "high risk" for neurocognitive dysfunction, because of neurologic abnormalities or a history of intensive focal cranial irradiation, from healthy "low-risk" survivors and siblings.

CONCLUSIONS

The questionnaire demonstrated excellent reliability, as well as construct and discriminative validity. It appears to be a practical and efficient tool for monitoring neurocognitive outcomes in adult survivors of pediatric cancer.

Evidence-based assessment of cognitive functioning in pediatric psychology

OBJECTIVE

To review the evidence base for measures of cognitive functioning frequently used within the field of pediatric psychology.

METHODS

From a list of 47 measures identified by the Society of Pediatric Psychology (Division 54) Evidence-Based Assessment Task Force Workgroup, 27 measures were included in the review. Measures were organized, reviewed, and evaluated according to general domains of functioning (e.g., attention/executive functioning, memory).

RESULTS

Twenty-two of 27 measures reviewed demonstrated psychometric properties that met "Well-established" criteria as set forth by the Assessment Task Force. Psychometric properties were strongest for measures of general cognitive ability and weakest for measures of visual-motor functioning and attention.

CONCLUSIONS

We report use of "Well-established" measures of overall cognitive functioning, nonverbal intelligence, academic achievement, language, and memory and learning. For several specific tests in the domains of visual-motor functioning and attention, additional psychometric data are needed for measures to meet criteria as "Well established."

Brain tumors in children and adolescents: cognitive and psychological disorders at different ages

Cognitive and psychological disorders are among the most frequently observed sequelae in brain tumor survivors. The goal of this work was to verify the presence of these disorders in a group of children and adolescents diagnosed with brain tumor before age 18 years, differentiate these disorders according to age of assessment, identify correlations between the two types of impairments and define possible associations between these impairments and clinical variables. The study involved 76 patients diagnosed with brain tumor before age 18 years. Three age groups were formed, and all the patients received a standardized battery of age-matched cognitive and psychological tests. According to our findings, all three groups present with cognitive and psychological-behavioral disorders. Their frequency varies according to age of onset and is strongly associated to time since diagnosis. The performance intelligence quotient (PIQ) was more impaired than the verbal intelligence quotient (VIQ). Internalizing problems, withdrawal and social problems were the most frequent psychological disorders. Correlations were found between cognitive impairment and the onset of the main psychological and behavioral disorders. These findings are relevant as they point out the long-term outcome of brain tumor survivors. Hence, the recommendation to diversify psychological interventions and rehabilitation plans according to the patients' age.

Polymorphisms of genes controlling homocysteine levels and IQ score following the treatment for childhood ALL

Introduction: One of the causes of long-term morbidity associated with the treatment of acute lymphoblastic leukemia (ALL) is late neurotoxicity manifesting as impairment of higher cognitive functions. Cranial radiation therapy (CRT) and chemotherapeutic agents, particularly methotrexate (MTX), are often suggested to be major contributing factors for its development. Homocysteinemia that arises as a result of MTX-induced folate depletion was proposed to play a role in MTX-related neurotoxicity. Several enzymes are essential to maintain the homocysteine levels. Their different functional forms, associated with common genetic polymorphisms, may modulate homocysteine levels and thereby influence MTX-associated neurotoxicity. Objectives: To test this hypothesis we assessed whether the variants of the methylene tetrahydrofolate reductase (MTHFR), methionine synthase (MTR), methionine synthase reductase (MTRR), cystathionine β-synthase (CBS) and endothelial nitric acid synthase (eNOS, NOS3) genes, acting either independently or in conjunction with other risk factors, influenced the cognitive functioning in ALL patients. The influence of the genes was measured by estimating the change in IQ scores over a period of 4 years post ALL diagnosis. Results: Two variants, the CBS 844ins68 polymorphism and NOS3 894T homozygosity, were associated with a change in IQ scores (p = 0.01 and 0.007, respectively). A multivariate model obtained through step-wise selection pointed to the importance of the NOS3 894TT genotype only. This effect appears to be dependent on CRT; IQ decline was apparent among individuals with the 894TT genotype who received radiation therapy (p = 0.03). Furthermore, additional factors affecting IQ were identified, including the treatment administered (i.e., CRT; p = 0.02) and a younger age at diagnosis (p = 0.003), and the modifying effect of the treatment protocols was also noted (p = 0.04). Conclusion: The results suggest that NOS3 genotyping might identify individuals that are susceptible to intellectual impairment following ALL treatment.

Online exclusive: behavioral adjustment of children and adolescents with cancer: teacher, parent, and self-report

PURPOSE/OBJECTIVES

To describe behavioral adjustment in children and adolescents with acute lymphoblastic leukemia (ALL) and to determine whether behavioral adjustment is correlated with cognitive and academic abilities.

DESIGN

Descriptive, cross-sectional design.

SETTING

Two pediatric oncology treatment centers.

SAMPLE

47 children and adolescents who had been receiving ALL therapy for at least one year or who were off therapy for no more than three years and their parents and teachers. Wechsler Intelligence Scale for Children-Revised (WISC-R) and Wide Range Achievement Test-Revised (WRAT-R) data were available on a subset of 17 subjects.

METHODS

Parent, teacher, and self-report Behavioral Assessment System for Children (BASC) ratings were used to measure behavioral adjustment. WISC-R measured cognitive abilities, and WRAT-R measured academic abilities. Demographic, family, and treatment-related data also were collected.

MAIN RESEARCH VARIABLES

Behavioral adjustment and cognitive and academic abilities.

FINDINGS

At least 20% of teacher ratings for somatization, learning problems, leadership, and study skills; parent ratings for somatization, adaptability, attention problems, withdrawal, anxiety, social skills, and depression; and self-report ratings for anxiety and attitude to school were in the at-risk range (i.e., presence of significant problems that require treatment). The majority of teacher BASC ratings were correlated significantly with WISC-R and WRAT-R scores. Self-report depression and social stress ratings were correlated significantly with some WISC-R and WRAT-R scores. Treatment-related experiences such as body image alterations and mental and emotional problems were associated with problematic behaviors, including depression, somatization, withdrawal, and social stress.

CONCLUSIONS

Youth with ALL are at risk for some behavioral adjustment problems, particularly anxiety, somatization, adaptability, attention, and withdrawal. Cognitive and academic abilities are associated with some dimensions of behavioral adjustment.

IMPLICATIONS FOR NURSING

Findings suggest the need for ongoing assessment of behavioral adjustment and cognitive and academic abilities of children with ALL. Behavioral interventions that target at-risk mannerisms, such as somatization, depression, anxiety, and social stress, are needed. Central nervous system treatment may contribute to behavioral adjustment problems, as well as to cognitive and academic problems. Strategies to improve academic abilities also may have a positive effect on behavioral adjustment.

Cognitive outcome of long-term survivors of multisystem langerhans cell histiocytosis: a single-institution, cross-sectional study

PURPOSE

Damage to the CNS, including the cerebellum, and to the hypothalamopituitary axis, is documented in Langerhans cell histiocytosis (LCH). Neuropsychologic deficits have been recognized, but this is the first study in which cognitive function has been systematically assessed in a cohort of patients.

PATIENTS AND METHODS

Twenty-eight long-term survivors of multisystem LCH (mean age, 15.1 years) were investigated for intelligence, memory and learning, language, and academic attainments.

RESULTS

The mean intelligence quotient (IQ) of the entire group was not significantly different from the mean of the population (ie, mean +/- SD, 100 +/- 1), but there were wide ranges (Full-Scale IQ [FSIQ]: mean, 93.6; range, 61.7 to 134; Performance IQ [PIQ]: mean, 92.2; range, 46 to 136; and Verbal IQ [VIQ]: mean, 93.7; range, 64.2 to 126). CNS involvement was a significant risk factor for lower scores, but sex, diabetes insipidus, and cranial radiotherapy were not. The CNS group had lower VIQ, PIQ, and FSIQ than patients with no CNS involvement (no CNS group: mean +/- SD FSIQ, 102.3 +/- 15.6; CNS group: mean +/- SD FSIQ, 73.6 +/- 7.7; P <.001). A similar pattern of results was obtained for all other cognitive measures. Even when effects of reduction in FSIQ were taken into account, specific deficits were found in patients in the CNS group.

CONCLUSION

Long-term survivors of multisystem LCH, particularly patients with CNS involvement, may develop significant cognitive deficits. All patients should have formal, repeated neuropsychologic assessment as part of long-term follow-up, which will enable abnormalities to be detected early so that appropriate supportive measures can be offered.

Cognitive functions of adolescent childhood cancer survivors assessed by event-related potentials

BACKGROUND

Neurophysiological methods were applied to examine subtle central nervous system (CNS) adverse effects for adolescent childhood cancer survivors. We analyzed auditory event-related potentials (ERPs)-P300 and MMN/P3a complex-to find out whether there was impaired attention orientation in asymptomatic cancer survivors, and whether these ERP methods could be used as more objective tools in detecting those survivors who might need academic testing. Previous clinical studies of P300 have focused on leukemia survivors. MMN for cancer survivors has not been reported.

PROCEDURE

The subjects were survivors of childhood leukemia (n=11) and solid tumors (n=8), as well as healthy controls (n=10). The mean age was 15.5 years for survivors and 15.9 years for controls. Pure sine-wave tones (500 and 553 Hz, 100 ms) were used as stimuli in an oddball paradigm. The ERPs to frequency change were measured. MMN recordings were performed in a passive non-attended situation where the subject was watching a voiceless video cartoon. P300 was produced thereafter, but in an active attend situation, by the same auditory oddball paradigm as MMN.

RESULTS

A significant difference was detected between the groups for the latency of P300 at electrodes Cz (P = 0.03) and C4 (P = 0.05). The cancer survivors had prolonged P300 latencies as an indication of prolonged short-term memory processing. The area and latency parameters of MMN did not differ significantly between the study groups, but in cancer survivors, the area and the mean amplitude of the subsequent P3a wave were diminished. The results indicate that the discrimination process was not as easy for the survivors as for the controls. However, it seems that in cancer survivors the basic mechanism starting attention shift to novel stimuli is not impaired.

CONCLUSIONS

These results indicate that it is important to carefully evaluate the proper methods for the teaching of children who are survivors of malignancies. The auditory information may not always lead to the best possible learning results.

CNS germinoma: disease control and long-term functional outcome for 12 children treated with craniospinal irradiation

PURPOSE

To provide evidence that radiation therapy alone in the form of craniospinal irradiation (CSI) and a boost to the primary site of disease provides effective disease control and limited additional morbidity for patients with CNS germinoma.

METHODS AND MATERIALS

Twelve patients with a median age of 12 years (range 9-16 years) with CNS germinoma were treated with CSI (median 25.6 Gy, range 23.4-32 Gy) and a boost to the primary site of disease (50.4 Gy, range 45-54 Gy) between January 1987 and June 1998. All patients were biopsied prior to radiation therapy and none received chemotherapy. No patients were lost to follow-up and the majority had long-term (> 45 month) pre- and postirradiation endocrine and psychology assessment.

RESULTS

All 12 patients are alive and no failures have occurred with a median follow-up of 69 months (range 14-143 months). Preirradiation endocrine deficiencies were present in 6 of 6 suprasellar tumors and 1 of 6 pineal tumors; with follow-up there was no substantial difference between age and gender adjusted pre- and postirradiation stature and weight. With long-term follow-up, there were no significant differences between pre- and postirradiation full-scale, verbal, and performance IQ scores.

CONCLUSIONS

This study confirms the ability of radiation therapy alone to achieve disease control with a high rate of success in pediatric patients and demonstrates that the treatment toxicity faced by these patients may be less than anticipated. Because these patients present with substantial preexisting morbidity at diagnosis and may be of an age where the potential for radiation-related side effects is relatively small, the superiority of treatment alternatives may be difficult to prove.