Investigating verbal and visual auditory learning after conformal radiation therapy for childhood ependymoma

Social determinants of cognitive outcomes in survivors of pediatric brain tumors treated with conformal radiation therapy

BACKGROUND

Social determinants of health including parental occupation, household income, and neighborhood environment are predictors of cognitive outcomes among healthy and ill children; however, few pediatric oncology studies have investigated this relationship. This study utilized the Economic Hardship Index (EHI) to measure neighborhood-level social and economic conditions to predict cognitive outcomes among children treated for brain tumors (BT) with conformal radiation therapy (RT).

METHODS

Two hundred and forty-one children treated on a prospective, longitudinal, phase II trial of conformal photon RT (54-59.4 Gy) for ependymoma, low-grade glioma, or craniopharyngioma (52% female, 79% white, age at RT = 7.76 ± 4.98 years) completed serial cognitive assessments (intelligence quotient [IQ], reading, math, and adaptive functioning) for ten years. Six US census tract-level EHI scores were calculated for an overall EHI score: unemployment, dependency, education, income, crowded housing, and poverty. Established socioeconomic status (SES) measures from the extant literature were also derived.

RESULTS

Correlations and non-parametric tests revealed EHI variables share modest variance with other SES measures. Income, unemployment, and poverty overlapped most with individual SES measures. Linear mixed models, accounting for sex, age at RT, and tumor location, revealed EHI variables predicted all cognitive variables at baseline and change in IQ and math over time, with EHI overall and poverty most consistent predictors. Higher economic hardship was associated with lower cognitive scores.

CONCLUSIONS

Neighborhood-level measures of socioeconomic conditions can help inform understanding of long-term cognitive and academic outcomes in survivors of pediatric BT. Future investigation of poverty's driving forces and the impact of economic hardship on children with other catastrophic diseases is needed.

The impact of socioeconomic status (SES) on cognitive outcomes following radiotherapy for pediatric brain tumors: a prospective, longitudinal trial

BACKGROUND

Socioeconomic status (SES) is a determinant of cognitive and academic functioning among healthy and ill children; however, few pediatric oncology studies examine SES and long-term cognitive functioning. The current study systematically investigated SES as a predictor of cognitive outcomes among children treated for localized brain tumors (BT) with photon radiation therapy (RT).

METHODS

248 children treated on a prospective, longitudinal, phase II trial of conformal RT (54-59.4 Gy) for ependymoma, low-grade glioma, or craniopharyngioma were monitored serially with cognitive assessments (intelligence quotient [IQ], reading, math, attention, adaptive function) for 10 years (2209 observations, median age at RT = 6.6 years, 48% male, 80% Caucasian). SES was derived from the Barratt Simplified Measure of Social Status, which incorporates parental occupation, education, and marital status.

RESULTS

Overall, SES scores fell in the low range (Barratt median = 37). At pre-RT baseline, linear mixed models revealed significant associations between SES and IQ, reading, math, attention, and adaptive function, with higher SES associated with better performance (P < .005). SES predicted change over time in IQ, reading, and math; higher SES was associated with less decline (P < .001). Accounting for sex and age at RT, SES remained predictive of IQ, reading, and math. Analysis of variance revealed a greater relative contribution of SES than sex or age at RT to reading and math.

CONCLUSIONS

SES represents a novel predictor of cognitive performance before and after RT for pediatric BT. These findings have broad implications as high SES represents a protective factor. Developing interventions to mitigate the effects of low SES is warranted.

Neurocognitive Outcomes in Pediatric Patients Following Brain Irradiation

Advanced radiation techniques can reduce the severity of neurocognitive sequelae in young brain tumor patients. In the present analysis, we sought to compare neurocognitive outcomes after proton irradiation with patients who underwent photon radiotherapy (RT) and surgery. Neurocognitive outcomes were evaluated in 103 pediatric brain tumor patients (proton RT n = 26, photon RT n = 30, surgery n = 47) before and after treatment. Comparison of neurocognitive outcomes following different treatment modalities were analyzed over four years after treatment completion. Longitudinal analyses included 42 months of follow-up after proton RT and 55 months after photon RT and surgery. Neurocognitive assessment included standardized tests examining seven domains. A comparison of neurocognitive outcomes after RT (proton and photon with >90% additional surgery) and surgery showed no significant differences in any neurocognitive domain. Neurocognitive functioning tests after proton RT failed to identify alterations compared to baseline testing. Long-term follow up over four years after photon RT showed a decrease in non-verbal intelligence (-9.6%; p = 0.01) and visuospatial construction (-14.9%; p = 0.02). After surgery, there was a decline in non-verbal intelligence (-10.7%; p = 0.01) and processing speed (14.9%; p = 0.002). Differences in neurocognitive outcomes between RT and surgical cohorts in direct intermodal comparison at long-term follow-up were not identified in our study, suggesting that modern radiation therapy does not affect cognition as much as in the past. There were no alterations in long-term neurocognitive abilities after proton RT, whereas decline of processing speed, non-verbal intelligence, and visuospatial abilities were observed after both photon RT and surgery. Domains dependent on intact white matter structures appear particularly vulnerable to brain tumor treatment irrespective of treatment approach.

Trajectories of psychosocial and cognitive functioning in pediatric patients with brain tumors treated with radiation therapy

BACKGROUND

Pediatric patients with brain tumors who are treated with radiation therapy (RT) are at risk for neurocognitive and psychosocial late effects. Research to date has primarily examined these outcomes at a group level and in isolation. Advanced statistical techniques allow for person-centered analyses, as well as examination of relationships between domain-specific trajectories.

METHODS

Patients with brain tumors (craniopharyngioma, ependymoma, low-grade astrocytoma, high-grade astrocytoma) were enrolled on a phase II clinical trial of RT. Three hundred and fifty patients completed serial neurocognitive assessments as part of their treatment monitoring, including pre-RT baseline, 6 months post-RT, and then yearly for 5 years. This secondary analysis focused on outcomes of cognition (estimated IQ, parent-reported attention problems) and psychosocial effects (parent-reported socialization and social problems) post-RT.

RESULTS

Latent growth curve modeling indicated that estimated IQ and socialization were best served by quadratic models, while attention and social problems were best served by linear models. Growth mixture modeling indicated 3-class models were the best fit for IQ and socialization, and 2-class models for attention and social problems. Baseline IQ and socialization scores were associated, but there was no association over time. Young age at diagnosis and pre-RT treatments (surgery, chemotherapy) were associated with class membership.

CONCLUSIONS

Person-centered statistical analyses provide rich information regarding the variability in neurocognitive and psychosocial functioning following RT for pediatric brain tumor. While many patients do well over time, a subset are exhibiting significant cognitive and/or psychosocial deficits. Class membership was associated with some medical factors (eg, pre-radiation surgery/chemotherapy, age at diagnosis, shunted hydrocephalus).

Improved neuropsychological outcomes following proton therapy relative to X-ray therapy for pediatric brain tumor patients

BACKGROUND

Survivors of pediatric brain tumors are at risk for impaired development in multiple neuropsychological domains. The purpose of this study was to compare neuropsychological outcomes of pediatric brain tumor patients who underwent X-ray radiotherapy (XRT) versus proton radiotherapy (PRT).

METHODS

Pediatric patients who underwent either XRT or PRT and received posttreatment age-appropriate neuropsychological evaluation-including measures of intelligence (IQ), attention, memory, visuographic skills, academic skills, and parent-reported adaptive functioning-were identified. Multivariate analyses were performed to assess differences in neuropsychological outcomes and included tests for interaction between treatment cohort and follow-up time.

RESULTS

Between 1998 and 2017, 125 patients with tumors located in the supratentorial (17.6%), midline (28.8%), or posterior fossa (53.6%) compartments received radiation and had posttreatment neuropsychological evaluation. Median age at treatment was 7.4 years. The PRT patient cohort had higher estimated SES and shorter median time from radiotherapy completion to last neuropsychological evaluation (6.7 vs 2.6 y, P < 0.001). On multivariable analysis, PRT was associated with higher full-scale IQ (β = 10.6, P = 0.048) and processing speed (β = 14.4, P = 0.007) relative to XRT, with trend toward higher verbal IQ (β = 9.9, P = 0.06) and general adaptive functioning (β = 11.4, P = 0.07). Planned sensitivity analyses truncating follow-up interval in the XRT cohort re-demonstrated higher verbal IQ (P = 0.01) and IQ (P = 0.04) following PRT, with trend toward improved processing speed (P = 0.09).

CONCLUSIONS

PRT is associated with favorable outcomes for intelligence and processing speed. Combined with other strategies for treatment de-intensification, PRT may further reduce neuropsychological morbidity of brain tumor treatment.

The European Society of Paediatric Oncology Ependymoma-II program Core-Plus model: Development and initial implementation of a cognitive test protocol for an international brain tumour trial

It is increasingly accepted that survival alone is an inadequate measure of the success of childhood brain tumour treatments. Consequently, there is growing emphasis on capturing quality of survival. Ependymomas are the third most frequently occurring brain tumours in childhood and present significant clinical challenges. European Society of Paediatric Oncology Ependymoma II is a comprehensive international program aiming to evaluate outcomes under different treatment regimens and improve diagnostic accuracy. Importantly, there has been agreement to lower the age at which children with posterior fossa ependymoma undergo focal irradiation from three years to either eighteen months or one year of age. Hitherto radiotherapy in Europe had been reserved for children over three years due to concerns over adverse cognitive outcomes following irradiation of the developing brain. There is therefore a duty of care to include longitudinal cognitive follow-up and this has been agreed as an essential trial outcome. Discussions between representatives of 18 participating European countries over 10 years have yielded European consensus for an internationally accepted test battery for follow-up of childhood ependymoma survivors. The 'Core-Plus' model incorporates a two-tier approach to assessment by specifying core tests to establish a minimum dataset where resources are limited, whilst maintaining scope for comprehensive assessment where feasible. The challenges leading to the development of the Core-Plus model are presented alongside learning from the initial stages of the trial. We propose that this model could provide a solution for future international trials addressing both childhood brain tumours and other conditions associated with cognitive morbidity.

Impact of radiation therapy and extent of resection for ependymoma in young children: A population-based study

BACKGROUND

Young children with posterior fossa ependymoma (PF-EPN) have a worse prognosis than older children, and they have a unique molecular profile (PF-EPN-A subtype). Alternative treatment strategies are often used in these young patients, and their prognostic factors are less clear.

METHODS

We characterized the prognostic factors and treatment outcomes of 482 patients between ages 0 and 3 years with the diagnosis of ependymoma identified from the Surveillance, Epidemiology, and End Results registry (1973-2013).

RESULTS

Radiation therapy (RT) was delivered to 52.3% of patients, and gross total resection (GTR) was performed in 51.0% of patients. Overall survival (OS) at 10 years was 48.4% with median follow-up of 3.3 years. WHO grade was not predictive of OS. Extent of resection was significant for survival; the 10-year OS with GTR was 61.0%, and with subtotal resection (STR) and biopsy was 38.2% and 35.0%, respectively (P < 0.001). RT significantly benefitted OS for both grades II and III. The 10-year OS for grade II was 50.5% with RT and 43.4% without (P = 0.030); 10-year OS for grade III was 66.0% with RT and 40.0% without (P = 0.002). Multivariate analysis showed significantly improved OS with RT (hazard ratio [HR] 0.601, 95% CI: 0.439-0.820, P = 0.001) and GTR (HR 0.471, 95% CI: 0.328-0.677, P < 0.0001).

CONCLUSIONS

Ependymoma outcomes in patients within 0-3 years of age significantly improved with RT and GTR. Histopathologic grading of ependymoma demonstrated no prognostic significance. Given the poor OS for this population and unique genetic profile, future prospective studies with molecular-based stratification should be performed to evaluate additional prognostic factors.

Pretreatment Cognition in Patients Diagnosed With Pediatric Brain Tumors

BACKGROUND

There is a large body of literature identifying risk factors for the long-term cognitive alterations found in survivors of pediatric brain tumors. Less is known about baseline cognitive functioning in this population, but studies suggest that cognitive dysfunctions are often present at the time of diagnosis. This study aimed to identify potential risk factors for lower cognitive function at the time of pediatric brain tumor diagnosis.

METHODS

Participants were children and adolescents (n = 101) diagnosed with a pediatric brain tumor between 2006 and 2015, who underwent a pretreatment neuropsychologic assessment. Multivariate regression models were used to estimate the association between gender, age at diagnosis, tumor size and location, increased intracranial pressure, epilepsy, and six different indicators of cognitive functioning.

RESULTS

Overall, cognitive performance was relatively intact, with results close to norm means, but impairments were found in memory and cognitive processing speed. Male gender, older age, epilepsy, increased intracranial pressure, and larger tumors were all associated with lower cognitive function at the time of brain tumor diagnosis; whereas tumor location was not.

CONCLUSIONS

Pretreatment neuropsychologic assessments, with some adjustments, can be carried out with children and adolescents with brain tumors. Our study adds to a small but growing body of literature documenting cognitive impairments at the time of diagnosis; these impairments may partly explain the longer-term deficits that commonly occur in pediatric brain tumor survivors. Consistent with previous research, pretreatment impairments were more common among boys, older children, and those with increased intracranial pressure, epilepsy, and larger tumors. The relationship between baseline and longer-term cognitive deficits requires further examination.

Current Clinical Challenges in Childhood Ependymoma: A Focused Review

Ependymoma is a locally aggressive tumor with metastatic potential that arises in diverse locations throughout the brain and spine in children. Tumor and treatment may result in significant morbidity. Cure remains elusive for many patients owing to diverse biology and resistance to conventional therapy. The implementation of systematic postoperative irradiation in clinical trials during the past 20 years has increased the proportion of patients achieving durable disease control with excellent results, as measured by objective functional outcome measures. Clinical, pathologic, and molecular risk stratification should be used to refine treatment regimens for children with ependymoma to reduce the risk of complications associated with therapy and increase the rate of disease control in the setting of combined modality or more intensive therapy. This review covers standards of care and current clinical trials for children with ependymoma, emphasizing the history and evolution of treatment regimens during the past 20 years and the clinical questions they hoped to address.

Final results of the second prospective AIEOP protocol for pediatric intracranial ependymoma

BACKGROUND

This prospective study stratified patients by surgical resection (complete = NED vs incomplete = ED) and centrally reviewed histology (World Health Organization [WHO] grade II vs III).

METHODS

WHO grade II/NED patients received focal radiotherapy (RT) up to 59.4 Gy with 1.8 Gy/day. Grade III/NED received 4 courses of VEC (vincristine, etoposide, cyclophosphamide) after RT. ED patients received 1-4 VEC courses, second-look surgery, and 59.4 Gy followed by an 8-Gy boost in 2 fractions on still measurable residue. NED children aged 1-3 years with grade II tumors could receive 6 VEC courses alone.

RESULTS

From January 2002 to December 2014, one hundred sixty consecutive children entered the protocol (median age, 4.9 y; males, 100). Follow-up was a median of 67 months. An infratentorial origin was identified in 110 cases. After surgery, 110 patients were NED, and 84 had grade III disease. Multiple resections were performed in 46/160 children (28.8%). A boost was given to 24/40 ED patients achieving progression-free survival (PFS) and overall survival (OS) rates of 58.1% and 68.7%, respectively, in this poor prognosis subgroup. For the whole series, 5-year PFS and OS rates were 65.4% and 81.1%, with no toxic deaths. On multivariable analysis, NED status and grade II were favorable for OS, and for PFS grade II remained favorable.

CONCLUSIONS

In a multicenter collaboration, this trial accrued the highest number of patients published so far, and results are comparable to the best single-institution series. The RT boost, when feasible, seemed effective in improving prognosis. Even after multiple procedures, complete resection confirmed its prognostic strength, along with tumor grade. Biological parameters emerging in this series will be the object of future correlatives and reports.

Neuroplastic Response After Radiation Therapy for Pediatric Brain Tumors: A Pilot Study

PURPOSE

Clinically effective measurement of cognitive toxicity from photon radiation therapy (XRT) should be accurate, sensitive, and specific. This pilot study tested translational findings on phasic changes in children's memory systems that are sensitive and insensitive to toxic XRT effects to identify a possible neuroplastic effect.

METHODS AND MATERIALS

Memory processes were prospectively tested before XRT and at 3 later time points up to 2 years in 35 children with mixed primary brain tumors who had not experienced recurrence. Memory processes were verbal-semantic, visual-semantic, and visual-perceptual, including accuracy, speed to recall, encoding, retrieval, and recognition. The mixed-effects model included time (to estimate slope), covariates (age, tumor locus, XRT field, and medications) as fixed effects, and individual random intercepts. A sensitivity analysis examined the influence of XRT dose to the hippocampi on memory.

RESULTS

Retrieval from long-term verbal-semantic memory declined 2 months after completing XRT, as seen in adults, and was lowest at 1 year, which was delayed in comparison with adults. Double dissociation from visual-perceptual memory at baseline and 2 months was found, consistent with adults. Recovery was demonstrated 2 years after XRT. Patterns were unchanged when dose to hippocampus was included in the model.

CONCLUSIONS

Verbal and semantic long-term retrieval is specifically sensitive to XRT-related cognitive dysfunction, without effect on visual-perceptual memory. Children reached nadir in XRT-sensitive memory 1 year after XRT and recovered by 2 years, which is later than that observed in adults. The protracted period of post-XRT injury may represent the maturation of the human hippocampus and white matter into late adolescence.

Monitoring and Assessment of Neuropsychological Outcomes as a Standard of Care in Pediatric Oncology

Central nervous system cancers or exposure to CNS-directed therapies increase risk for neuropsychological deficits. There are no accepted guidelines for assessment of neuropsychological functioning in this population. A multifaceted literature search was conducted and relevant literature reviewed to inform the guidelines. Studies of neuropsychological outcomes are widely documented in the pediatric oncology literature. There is strong evidence of need for neuropsychological assessment, but insufficient evidence to guide the timing of assessment, nor to recommend specific interventions. Children with brain tumors and others at high risk for neuropsychological deficits should be monitored and assessed for neuropsychological deficits.

Effect of cerebellum radiation dosimetry on cognitive outcomes in children with infratentorial ependymoma

PURPOSE

Cognitive decline is a recognized effect of radiation therapy (RT) in children treated for brain tumors. The importance of the cerebellum and its contribution to cognition have been recognized; however, the effect of RT on cerebellum-linked neurocognitive deficits has yet to be explored.

METHODS AND MATERIALS

Seventy-six children (39 males) at a median 3.3 years of age (range, 1-17 years old) were irradiated for infratentorial ependymoma from 1997 to 2008. The total prescribed dose was 54 to 59.4 Gy administered to the postoperative tumor bed with 5- or 10-mm clinical target volume margin. Age-appropriate cognitive and academic testing was performed prior to the start of RT and was then repeated at 6 months and annually throughout 5 years. The anterior and posterior cerebellum and other normal brain volumes were contoured on postcontrast, T1-weighted postoperative magnetic resonance images registered to treatment planning computed tomography images. Mean doses were calculated and used with time after RT and other clinical covariates to model their effect on neurocognitive test scores.

RESULTS

Considering only the statistically significant rates in longitudinal changes for test scores and models that included mean dose, there was a correlation between mean infratentorial dose and intelligence quotient (IQ; -0.190 patients/Gy/year; P=.001), math (-0.164 patients/Gy/year; P=.010), reading (-0.137 patients/Gy/year; P=.011), and spelling scores (-0.147 patients/Gy/year; P=.012), where Gy was measured as the difference between the mean dose received by an individual patient and the mean dose received by the patient group. There was a correlation between mean anterior cerebellum dose and IQ scores (-0.116 patients/Gy/year; P=.042) and mean posterior cerebellum dose and IQ (-0.150 patients/Gy/year; P=.002), math (-0.120 patients/Gy/year; P=.023), reading (-0.111 patients/Gy/year; P=.012), and spelling (-0.117 patients/Gy/year; P=.015) scores.

CONCLUSIONS

Sparing portions of the cerebellum should be considered in RT planning for children with infratentorial ependymoma because of the potential impact of radiation dose on cognitive function.

The relationship between working memory and cerebral white matter volume in survivors of childhood brain tumors treated with conformal radiation therapy

Survivors of childhood brain tumors (BTs) treated with CNS-directed therapy show changes in cerebral white matter that are related to neurocognitive late effects. We examined the association between white matter volume and working memory ability in survivors treated with conformal radiation therapy (CRT). Fifty survivors (25 males, age at assessment = 13.14 ± 2.88, age at CRT = 7.41 ± 3.41 years) completed Digit Span from the Wechsler Intelligence Scales for Children, 4th Edition and experimental Self-Ordered Search (SOS) tasks as measures of working memory. Caregiver ratings were obtained using the Behavior Rating Inventory of Executive Function. MRI exams were acquired on a 1.5 T scanner. Volumes of normal appearing white matter (NAWM) were quantified using a well-validated automated segmentation and classification program. Correlational analyses demonstrated that NAWM volumes were significantly larger in males and participants with tumors located in the infratentorial space. Correlations between NAWM volume and Digit Span Backward were distributed across anterior and posterior regions, with evidence for greater right hemisphere involvement (r = .32-.34, p ≤ .05). Correlations between NAWM volume with Digit Span Backward (r = .44-.52; p ≤ .05) and NAWM volume with SOS-Object Total (r = .45-.52, p ≤ .05) were of greater magnitude in females. No relationship was found between NAWM volume and caregiver report. Working memory performance in survivors of pediatric BTs treated with CRT are related to regionally specific NAWM volume. Developmental differences in cerebral myelination may explain findings of greater risk for neurocognitive late effects in female survivors. Future studies are needed to better isolate vulnerable white matter pathways, thus facilitating the development of neuroprotective interventions.

Impact of Craniospinal Dose, Boost Volume, and Neurologic Complications on Intellectual Outcome in Patients With Medulloblastoma

Purpose

To examine the impact of radiation (ie, craniospinal irradiation [CSR] dose and boost volume) and complications (ie, hydrocephalus and other neurologic complications, including mutism) on patterns of change in intellectual functioning in medulloblastoma survivors.

Patients and Methods

We conducted a retrospective review of 113 patients treated for medulloblastoma between 1983 and 2011 who were seen for neuropsychological assessment, including longitudinal follow-up of intellectual function. Patients were treated with either standard-dose CSR with a posterior fossa (PF) boost (n = 51), standard-dose CSR plus tumor bed (TB) boost (n = 9), reduced-dose CSR plus PF boost (n = 28), or reduced-dose CSR plus TB boost (n = 23), with or without chemotherapy. A subset of patients developed hydrocephalus that required cerebrospinal fluid (CSF) diversion (n = 54) and/or other neurologic complications (n = 40), more than half of which were postoperative mutism (n = 25). Growth curve analysis was used to determine stability or change in intelligence scores over time.

Results

Patients treated with reduced-dose CSR plus TB boost showed stable intellectual trajectories, whereas patients treated with higher doses and larger boost volumes experienced intellectual declines. Presence of complications was associated with worse intellectual outcome; however, hydrocephalus requiring CSF diversion and mutism differed in their pattern of decline.

Conclusion

These results improve our understanding of factors that impair intellectual outcome in patients treated for medulloblastoma. Lower doses of CSR and smaller boost volumes seem to mitigate intellectual decline. Our findings validate the use of TB boost and suggest PF boost should be reconsidered.

Emotional and behavioral functioning after conformal radiation therapy for pediatric ependymoma

PURPOSE

The standard of care for pediatric patients with ependymoma involves postoperative radiation therapy. Prior research suggests that conformal radiation therapy (CRT) is associated with relative sparing of cognitive and academic functioning, but little is known about the effect of CRT on emotional and behavioral functioning.

METHODS AND MATERIALS

A total of 113 patients with pediatric ependymoma underwent CRT using photons as part of their enrollment on an institutional trial. Patients completed annual evaluations of neurocognitive functioning during the first 5 years after CRT. Emotional and behavioral functioning was assessed via the Child Behavior Checklist.

RESULTS

Before CRT, emotional and behavioral functioning were commensurate with those of the normative population and within normal limits. After 5 years, means remained within normal limits but were significantly below the normative mean. Linear mixed models revealed a significant increase in attention problems over time. These problems were associated with age at diagnosis/CRT, tumor location, and extent of resection. A higher-than-expected incidence of school problems was present at all assessment points after baseline.

CONCLUSIONS

The use of photon CRT for ependymoma is associated with relatively stable emotional and behavioral functioning during the first 5 years after treatment. The exception is an increase in attention problems. Results suggest that intervening earlier in the survivorship period-during the first year posttreatment-may be beneficial.

Proton radiotherapy for pediatric central nervous system ependymoma: clinical outcomes for 70 patients

BACKGROUND

Ependymoma is treated with maximal surgical resection and localized radiotherapy. Minimizing unnecessary exposure to radiation is of paramount importance for young children. Proton radiotherapy (PRT) spares healthy tissues outside the target region, but reports of clinical outcomes are scarce. We report outcomes for 70 patients treated with PRT for intracranial ependymoma.

METHODS

Seventy patients with localized ependymoma treated with involved-field PRT at the Massachusetts General Hospital between October 2000 and February 2011 were included.

RESULTS

Median age at diagnosis was 38 months (range, 3 mo-20 y). Nineteen (27%) patients had supratentorial ependymoma and 51(73%) had infratentorial ependymoma. Forty-six (66%) had gross total resection (GTR), and 24 (34%) had subtotal resection (STR). At a median follow-up of 46 months, 3-year local control, progression-free survival, and overall survival were 83%, 76%, and 95%, respectively. STR was significantly associated with worse progression-free survival (54% vs 88%, P = .001) and overall survival (90% vs 97% for GTR, P = .001). In a subset of patients (n = 14), mean intelligence was 108.5 at baseline and 111.3 after mean 2.05 years of follow-up. In a larger group of patients (n = 28), overall adaptive skills were 100.1 at baseline and 100.8 after 2.21 years of follow-up. Few patients developed evidence of growth hormone deficiency, hypothyroidism, or hearing loss.

CONCLUSION

Outcomes for children treated with PRT compare favorably with the literature. STR correlated with inferior outcome. The young age at diagnosis and the proximity of critical structures in patients with ependymoma make PRT an ideal radiation modality.

Children's Oncology Group's 2013 blueprint for research: behavioral science

Behavioral science has long played a central role in pediatric oncology clinical service and research. Early work focused on symptom relief related to side effects of chemotherapy and pain management related to invasive medical procedures. As survival rates improved, the focused has shifted to examination of the psychosocial impact, during and after treatment, of pediatric cancer and its treatment on children and their families. The success of the clinical trials networks related to survivorship highlights an even more critical role in numerous domains of psychosocial research and care. Within the cooperative group setting, the field of behavioral science includes psychologists, social workers, physicians, nurses, and parent advisors. The research agenda of this group of experts needs to focus on utilization of psychometrically robust measures to evaluate the impact of treatment on children with cancer and their families during and after treatment ends. Over the next 5 years, the field of behavioral science will need to develop and implement initiatives to expand use of standardized neurocognitive and behavior batteries; increase assessment of neurocognition using technology; early identification of at-risk children/families; establish standards for evidence-based psychosocial care; and leverage linkages with the broader behavioral health pediatric oncology community to translate empirically supported research clinical trials care to practice.

Clinical controversies: proton therapy for pediatric tumors

Despite the claim in the published literature, the introduction of proton therapy for children is not analogous to the evolution of conformal photon irradiation relying on the understanding of the impact of altered dose distributions. The differences in radiobiological effect when comparing photons with protons mean that we are comparing a known entity with an unknown entity: the dose-volume histogram for proton therapy might mean something substantially different from the dose-volume histogram for photon therapy. The multifaceted difference between the 2 modalities supports the argument for careful evaluation, follow-up, and clinical trials with adverse event monitoring when using proton therapy in children. We review the current data on the outcome of proton therapy in a range of pediatric tumors and compare them with the often excellent results of photon therapy in the setting of multidisciplinary management of childhood cancer. It is hoped that the apparent dosimetric advantage of proton therapy over photons will lead to improved indications for therapy, disease control, and functional outcomes. Although physical dose distribution is of clear importance, the multimodality management of children by an expert pediatric oncology team and the availability of ancillary measures that improve the quality of treatment delivery may be more important than the actual beam. In addition, current estimates of the benefit of proton therapy over photon therapy based on toxicity reduction will only be realized when survivorship has been achieved. Once substantive proton therapy data become available, it will be necessary to demonstrate benefit in clinically relevant outcome measures in comparison with best existing photon outcome data. Such an effort will require improved funding and appreciation for late effects research. Only real clinical outcome data combined with better understanding of the radiobiological differences between protons and photons will help us to further reduce side effects in children and exploit the full curative potential of this relatively new modality.

Outcome of infants and young children with newly diagnosed ependymoma treated on the "Head Start" III prospective clinical trial

This study investigates the outcome of children <10 years old with newly-diagnosed ependymoma treated on the prospective multinational "Head Start" III clinical trial. Between April 2004 and July 2009, 19 children with newly-diagnosed ependymoma were enrolled. All children were to receive five induction chemotherapy cycles followed by one consolidation cycle of myelo-ablative chemotherapy and autologous hematopoietic cell rescue. Children between 6 and 10 years of age or with residual tumor prior to consolidation were to receive irradiation thereafter. Median age of 19 children (8 female) was 20 months at diagnosis. Median follow up was 44 months. The primary site was infratentorial in 11 and supratentorial in 8 patients. Gross total resection was achieved in 10 patients. After induction chemotherapy, all three supratentorial ependymoma patients with residual disease achieved a complete response (CR), while only one of six infratentorial patients with residual disease achieved CR. Three infratentorial patients developed progressive disease during induction chemotherapy. All four infratentorial patients with residual disease who underwent autologous hematopoietic cell transplant, failed to achieve CR. Four patients received focal irradiation following chemotherapy. The 3-year event free survival (EFS) and overall survival (OS) for supratentorial ependymoma were 86 ± 13 % and 100 % respectively. The 3-year EFS and OS for infratentorial ependymoma were 27 ± 13 % and 73 ± 13 % respectively. The role of intensive induction and consolidation chemotherapy in deferring irradiation should be investigated further in children with supratentorial ependymoma with residual disease following surgery. This approach appears ineffective in children with infratentorial ependymoma in the absence of irradiation.

Working memory performance among childhood brain tumor survivors

While longitudinal studies of children treated for brain tumors have consistently revealed declines on measures of intellectual functioning, greater specification of cognitive changes following treatment is imperative for isolating vulnerable neural systems and developing targeted interventions. Accordingly, this cross-sectional study evaluated the performance of childhood brain tumor survivors (n = 50) treated with conformal radiation therapy, solid tumor survivors (n = 40) who had not received central nervous system (CNS) -directed therapy, and healthy sibling controls (n = 40) on measures of working memory [Digit Span and computerized self-ordered search (SOS) tasks]. Findings revealed childhood brain tumor survivors were impaired on both traditional [Digit Span Backward- F(2,127) = 5.98; p < .01] and experimental [SOS-Verbal- F(2,124) = 4.18; p < .05; SOS-Object- F(2,126) = 5.29; p < .01] measures of working memory, and performance on working memory measures correlated with intellectual functioning (Digit Span Backward- r = .45; p < .0001; SOS- r = -.32 to -.26; p < .01). Comparison of performance on working memory tasks to recognition memory tasks (computerized delayed match-to-sample) offered some support for greater working memory impairment. This pattern of findings is consistent with vulnerability in functional networks that include prefrontal brain regions and has implications for the clinical management of children with brain tumors.

Learning and memory following conformal radiation therapy for pediatric craniopharyngioma and low-grade glioma

PURPOSE

The primary objective of this study was to examine whether children with low-grade glioma (LGG) or craniopharyngioma had impaired learning and memory after conformal radiation therapy (CRT). A secondary objective was to determine whether children who received chemotherapy before CRT, a treatment often used to delay radiation therapy in younger children with LGG, received any protective benefit with respect to learning.

METHODS AND MATERIALS

Learning and memory in 57 children with LGG and 44 children with craniopharyngioma were assessed with the California Verbal Learning Test-Children's Version and the Visual-Auditory Learning tests. Learning measures were administered before CRT, 6 months later, and then yearly for a total of 5 years.

RESULTS

No decline in learning scores after CRT was observed when patients were grouped by diagnosis. For children with LGG, chemotherapy before CRT did not provide a protective effect on learning. Multiple regression analyses, which accounted for age and tumor volume and location, found that children treated with chemotherapy before CRT were at greater risk of decline on learning measures than those treated with CRT alone. Variables predictive of learning and memory decline included hydrocephalus, shunt insertion, younger age at time of treatment, female gender, and pre-CRT chemotherapy.

CONCLUSIONS

This study did not reveal any impairment or decline in learning after CRT in overall aggregate learning scores. However, several important variables were found to have a significant effect on neurocognitive outcome. Specifically, chemotherapy before CRT was predictive of worse outcome on verbal learning in LGG patients. In addition, hydrocephalus and shunt insertion in craniopharyngioma were found to be predictive of worse neurocognitive outcome, suggesting a more aggressive natural history for those patients.

Stereotactic iodine-125 brachytherapy for treatment of inoperable focal brainstem gliomas of WHO grades I and II: feasibility and long-term outcome

Microsurgical resection is the most frequently suggested treatment option for accessible focal brainstem gliomas (F-BSG) of World Health Organization (WHO) grades I and II. Because of their location in the highly eloquent brain, however, resection is associated with permanent postoperative morbidity, ranging from 12 to 33 %. Only a few reports have suggested stereotactic brachytherapy (SBT) with implantation of iodine-125 seeds as a local treatment alternative. Between 1993 and 2010, 47 patients were treated with SBT (iodine-125 seeds; cumulative surface dose 50-65 Gy) for inoperable F-BSG, WHO grades I and II, in one of the largest reported patient series. We evaluated procedure-related complications, clinical outcome, and progression-free and overall survival (PFS, OS). Median follow-up was 81.6 months. Procedure-related mortality was zero. Within 30 days of seed implantation six patients (12.8 %) had transient neurological deficits. Two patients (4.3 %) deteriorated permanently. Space-occupying cysts occurred in six patients (12.8 %) after a median of 28.5 months, and required surgical intervention. Nine patients (19.1 %) presented with tumor relapse after a median of 56.6 months (range 7.9-118.0 months). For the remaining 38 patients complete response was observed for 23.4 %, partial response for 29.8 %, and stable disease for 27.7 %. Actuarial PFS was 97.7 ± 2.2, 92.8 ± 4.0, 81.2 ± 6.5, and 62.0 ± 10.4 % after 1, 2, 5, and 10 years, respectively. Corresponding OS was 100 ± 0.0 % (1 and 2 years), 97.4 ± 2.6 % (5 years), and 87.6 ± 7.0 % (10 years). SBT is a comparatively safe, minimally invasive, and highly effective local treatment option for patients with inoperable F-BSG WHO grades I and II; it merits further evaluation in prospective randomized trials.

A 5-year investigation of children's adaptive functioning following conformal radiation therapy for localized ependymoma

PURPOSE

Conformal and intensity modulated radiation therapies have the potential to preserve cognitive outcomes in children with ependymoma; however, functional behavior remains uninvestigated. This longitudinal investigation prospectively examined intelligence quotient (IQ) and adaptive functioning during the first 5 years after irradiation in children diagnosed with ependymoma.

METHODS AND MATERIALS

The study cohort consisted of 123 children with intracranial ependymoma. Mean age at irradiation was 4.60 years (95% confidence interval [CI], 3.85-5.35). Serial neurocognitive evaluations, including an age-appropriate IQ measure and the Vineland Adaptive Behavior Scales (VABS), were completed before irradiation, 6 months after treatment, and annually for 5 years. A total of 579 neurocognitive evaluations were included in these analyses.

RESULTS

Baseline IQ and VABS were below normative means (P<.05), although within the average range. Linear mixed models revealed stable IQ and VABS across the follow-up period, except for the VABS Communication Index, which declined significantly (P=.015). Annual change in IQ (-.04 points) did not correlate with annual change in VABS (-.90 to +.44 points). Clinical factors associated with poorer baseline performance (P<.05) included preirradiation chemotherapy, cerebrospinal fluid shunt placement, number and extent of surgical resections, and younger age at treatment. No clinical factors significantly affected the rate of change in scores.

CONCLUSIONS

Conformal and intensity modulated radiation therapies provided relative sparing of functional outcomes including IQ and adaptive behaviors, even in very young children. Communication skills remained vulnerable and should be the target of preventive and rehabilitative interventions.

Sequencing of local therapy affects the pattern of treatment failure and survival in children with atypical teratoid rhabdoid tumors of the central nervous system

PURPOSE

To assess the pattern of treatment failure associated with current therapeutic paradigms for childhood atypical teratoid rhabdoid tumors (AT/RT).

METHODS AND MATERIALS

Pediatric patients with AT/RT of the central nervous system treated at our institution between 1987 and 2007 were retrospectively evaluated. Overall survival (OS), progression-free survival, and cumulative incidence of local failure were correlated with age, sex, tumor location, extent of disease, and extent of surgical resection. Radiotherapy (RT) sequencing, chemotherapy, dose, timing, and volume administered after resection were also evaluated.

RESULTS

Thirty-one patients at a median age of 2.3 years at diagnosis (range, 0.45-16.87 years) were enrolled into protocols that included risk- and age-stratified RT. Craniospinal irradiation with focal tumor bed boost (median dose, 54 Gy) was administered to 18 patients. Gross total resection was achieved in 16. Ten patients presented with metastases at diagnosis. RT was delayed more than 3 months in 20 patients and between 1 and 3 months in 4; 7 patients received immediate postoperative irradiation preceding high-dose alkylator-based chemotherapy. At a median follow-up of 48 months, the cumulative incidence of local treatment failure was 37.5% ± 9%; progression-free survival was 33.2% ± 10%; and OS was 53.5% ± 10%. Children receiving delayed RT (≥1 month postoperatively) were more likely to experience local failure (hazard ratio [HR] 1.23, p = 0.007); the development of distant metastases before RT increased the risk of progression (HR 3.49, p = 0.006); and any evidence of disease progressionbefore RT decreased OS (HR 20.78, p = 0.004). Disease progression occurred in 52% (11/21) of children with initially localized tumors who underwent gross total resection, and the progression rate increased proportionally with increasing delay from surgery to RT.

CONCLUSIONS

Delayed RT is associated with a higher rate of local and metastatic disease progression in children with AT/RT. Current treatment regimens for pediatric patients with AT/RT are distinctly age stratified; novel protocols investigating RT volumes and sequencing are needed.

Region-specific radiotherapy and neuropsychological outcomes in adult survivors of childhood CNS malignancies

Childhood cancer survivors exposed to CNS irradiation are at increased risk for neurocognitive deficits; however, limited data exist linking outcomes with region-specific exposure to CNS irradiation. We report associations between region-specific radiation dose and self-reported neurocognitive and health-related quality of life (HRQOL) outcomes in 818 adult survivors of childhood central nervous system (CNS) malignancies from the Childhood Cancer Survivor Study. Survivors were compared with a sibling group and national normative samples to calculate standardized scores. Cumulative radiation dose was calculated for 4 specific brain regions. Logistic regression was used to estimate the association between radiation dose to specific brain regions and outcome measures of functional impairment adjusted for clinical and demographic factors, including sex and age at diagnosis. High radiation dose levels to temporal regions were associated with a higher risk for memory impairment (radiation doses ≥30 to <50 Gy: OR, 1.95; 95% CI, 1.01-3.78; dose ≥50 Gy: OR, 2.34; 95% CI, 1.25-4.39) compared with those with no radiation exposure. No such association was seen with radiation exposure to other regions. Exposure to temporal regions was associated with more social and general health problems, whereas exposure to frontal regions was associated with general health problems and physical performance limitations. Adult survivors of childhood CNS malignancies report higher rates of neuropsychological and HRQOL outcomes, which vary as a function of dose to specific neuroanatomical regions. Survivors with a history of radiation exposure to temporal brain regions are at increased risk for impairment in memory and social functioning.