Prospective study of health-related quality of life for children with brain tumors treated with proton radiotherapy

Core deficits and quality of survival after childhood medulloblastoma: a review

Background

Medulloblastoma is the most common malignant central nervous system tumor in children. Treatment most often includes surgical resection, craniospinal irradiation, and adjuvant chemotherapy. Although survival has improved dramatically, the tumor and its treatments have devastating long-term side effects that negatively impact quality of survival (QoS). The objective was to review the literature on QoS following childhood medulloblastoma.

Methods

This narrative review is based on a Medline database search and examination of the reference lists of papers selected.

Results

Frequent problems after medulloblastoma treatment include medical complications, such as long-term neurological and sensory (hearing loss) impairments; endocrine deficits, including growth problems; and secondary tumors. Neurocognitive impairment is repeatedly reported, with decreasing cognitive performances over time. Although all cognitive domains may be affected, low processing speed, attention difficulties, and working memory difficulties are described as the core cognitive deficits resulting from both cerebellar damage and the negative effect of radiation on white matter development. Long-term psychosocial limitations include low academic achievement, unemployment, and poor community integration with social isolation. Important negative prognostic factors include young age at diagnosis, conventional craniospinal radiotherapy, presence of postoperative cerebellar mutism, and perioperative complications. The influence of environmental factors, such as family background and interventions, remains understudied.

Conclusion

Future studies should focus on the respective impact of radiation, cerebellar damage, genomic and molecular subgroup parameters, and environmental factors on cognitive and psychosocial outcomes. Long-term (probably lifelong) follow-up into adulthood is required in order to monitor development and implement timely, suitable, multi-disciplinary rehabilitation interventions and special education or support when necessary.

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

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

Factors Affecting Health-Related Quality of Life in Children Undergoing Curative Treatment for Cancer: A Review of the Literature

BACKGROUND

Health-related quality of life (HRQoL) is an important measure to evaluate a child's reported treatment experience. Although there are numerous studies of HRQoL in children undergoing curative cancer treatment, there is limited literature on factors that influence this.

OBJECTIVE

To review published studies that describe the HRQoL and associated factors in children undergoing curative cancer treatment.

METHOD

Full-text publications in English from January 2005 to March 2013 were searched in PubMed, PsychINFO, and CINAHL for children ≤18 years of age undergoing curative cancer treatment. HRQoL-associated factors were categorized as cancer diagnosis, treatment, child, family, and community.

RESULTS

Twenty-six studies met the inclusion criteria. The most frequently used generic and cancer-specific instruments were PedsQL (Pediatric Quality of Life Inventory) Generic and PedsQL Cancer, respectively. Cancer diagnosis and treatment were the most frequently identified variables; fewer studies measured family and community domains. Gender, treatment intensity, type of cancer treatments, time in treatment, and cancer diagnosis were correlated with HRQoL.

CONCLUSION

Our study highlights the need to develop interventions based on diagnosis and treatment regimen to improve the HRQoL in children undergoing curative cancer treatment.

Proton therapy for pediatric and adolescent esthesioneuroblastoma

BACKGROUND

Esthesioneuroblastoma (EN) of the paranasal sinus comprises less than 3% of tumors of in pediatric and adolescent patients [1]. The collective adult literature indicates a critical role for radiotherapy in attaining cure [2], yet pediatric outcome data is limited. Radiation in pediatric patients with EN can cause significant morbidity due to the proximity of critical structures. Proton radiotherapy offers a potential dosimetric benefit that may improve long-term survival and toxicity outcomes in the pediatric population [3].

METHODS

We retrospectively identified eight patients treated for EN with proton radiotherapy from 2000-2013. Times to event clinical endpoints are summarized using the Kaplan-Meier methods and are from the date of radiotherapy completion. Toxicities are reviewed and graded according to CTCAE v. 4.0.

RESULTS

Median follow up was 4.6 years for survivors (range 0.8-9.4 years). The 4 year overall survival was 87.5%. Four of eight patients (one elective) had comprehensive neck radiotherapy. No local or regional failures were observed. Two patients failed distantly with diffuse leptomeningeal disease and intraparenchymal brain metastases, at 0.6 and 1.3 months respectively. Four patients developed radiation related late toxicities including endocrine dysfunction, two cases of grade 2 retinopathy and one case of grade 3 optic neuropathy.

CONCLUSIONS

In a limited cohort, proton radiotherapy appears to provide excellent locoregional disease control even in those patients with locally advanced disease and intracranial extension. Distant failure determined overall survival in our cohort. Toxicities were acceptable given disease location and extent.

Screening for cognitive deficits in 8 to 14-year old children with cerebellar tumors using self-report measures of executive and behavioral functioning and health-related quality of life

BACKGROUND

We aimed to identify a brief screening measure for detection of cognitive deficit in children treated for cerebellar tumors that would be useful in clinical practice.

METHODS

A sample of 72 children, aged 8-14 years, and within 3 years post diagnosis for standard-risk medulloblastoma (n = 37) or low-grade cerebellar astrocytoma (n = 35) and 38 children in a nontumor group were assessed using teacher-, parent-, and child-report of the Behavior Rating Inventory of Executive Function (BRIEF), Strengths and Difficulties Questionnaire (SDQ), and Pediatric Quality of Life Inventory (PedsQL). The accuracy of these scores as a screen for a full-scale Intelligence Quotient (FSIQ) < 80 on the Wechsler Intelligence Scale for Children (WISC-IV UK) was assessed using their receiver operating characteristic (ROC) curves.

RESULTS

The questionnaires with the highest areas under the ROC curves were the child- and parent-report PedsQL, the teacher-report BRIEF, and the SDQ. At optimal cutoff scores, their sensitivities (95% CIs) to cases of FSIQ < 80 were 84 (60-96)%, 65 (41-84)%, 79 (54-93)%, and 84 (60-96)%, and their specificities (95% CIs) were 79 (68-86)%, 87 (77-93)%, 77 (66-86)%, and 71 (64-84)% respectively. All cases of FSIQ < 80 screened positive on either teacher-report SDQ or self-report PedsQL.

CONCLUSIONS

The PedsQL child- and parent-report and the teacher-report BRIEF and SDQ have moderately good accuracy for discriminating between children with and without a FSIQ < 80. The PedsQL could be used in a clinical setting, and the BRIEF and SDQ in an educational setting, to screen for cases with FSIQ < 80 in children treated for brain tumors.

Embryonal brain tumors

Embryonal brain tumors are a heterogeneous group of neoplasms that primarily occur in infants and young children. They are highly cellular tumors with brisk mitotic activity, and they share a propensity for dissemination throughout the neuroaxis. Emerging molecular data enable improved diagnostic and prognostic discrimination for these tumors. Because of their aggressive potential, they are treated similarly with multimodality therapy including maximal safe resection, chemotherapy, and age- and risk-adapted radiotherapy. Craniospinal irradiation is commonly used in the treatment of these patients, especially in those older than 3 years. Because proton therapy allows for increased sparing of the anterior structures in craniospinal irradiation, there is a particular interest in using proton therapy to treat these young patients. For very young patients treated with focal fields only, proton therapy also decreases unnecessary radiation exposure to uninvolved intracranial structures. It is hoped that the use of proton therapy for these vulnerable patients will translate into decreased long-term neurocognitive, endocrine, vascular, and developmental effects, in addition to a decreased risk of second malignancies. This review describes the role of radiation in general and proton therapy in particular for the treatment of medulloblastoma, central nervous system primitive neuroectodermal tumors, atypical teratoid/rhabdoid tumors, and the recently described embryonal tumor with multilayered rosettes.

The use of proton therapy in the treatment of benign or low-grade pediatric brain tumors

Radiation therapy (RT) plays a critical role in the local tumor control of benign and low-grade central nervous system tumors in children but is not without the risk of long-term treatment-related sequelae. Proton therapy (PRT) is an advanced RT modality with a unique dose-deposition pattern that allows for treatment of a target volume with reduced scatter dose delivered to normal tissues compared with conventional photon RT and is now increasingly utilized in children with the hope of mitigating radiation-induced late effects. This article reviews the current literature evaluating the use of PRT in benign and low-grade pediatric central nervous system tumors such as low-grade glioma, craniopharyngioma, and ependymoma. Multiple dosimetric studies support the use of PRT by demonstrating the ability of PRT to better spare critical structures important for cognitive development, endocrine function, and hearing preservation and to reduce the total body dose associated with second malignancy risk. Early clinical data demonstrate that PRT is well tolerated with rates of local tumor control comparable to conventional photon RT series, and long-term clinical data are awaited.

Treatment tolerance of particle therapy in pediatric patients

Curative treatment of pediatric cancer not only focuses on long-term survival, but also on reducing treatment-related side effects. Advantages of particle therapy are mainly due to their physical ability of significantly reducing integral dose.

METHODS

Between January 2009 and December 2012, we treated 83 pediatric patients (aged 21 and younger) at the Heidelberg Ion Therapy Center at University Hospital of Heidelberg (HIT). In total 56 patients (67%) received proton irradiation, while 25 (30%) patients were treated with carbon ions (C12). Two patients received both treatments (3%). Treatment toxicity was analyzed retrospectively and documented according to the CTCAE/RTOG classification. In a second step, treatment toxicity from ion therapy was analyzed in comparison to treatment toxicity during photon irradiation of a comparable historical group of 19 pediatric patients.

RESULTS

In all patients, particle therapy was tolerated well (median follow-up time 3.7 months), children (20 patients) with at least two follow-up visits showed a median follow-up time of 10.2 months. During the first two months patients mainly suffered from radiogenic skin reaction (63%), mucositis (30%), headache and dizziness (35%) as well as nausea and vomiting (13%). Severe toxicity reaction (grade II-IV) was only seen in patients who had intensive simultaneous chemotherapy or who had undergone several operations in the irradiated area before radiotherapy (18%). Treatment toxicity during ion therapy was comparable to treatment toxicity from photon irradiation of a historical group.

CONCLUSIONS

In comparison to conventional therapy, patients with particle therapy do not suffer from increased acute treatment-related toxicity during the first months. More experience with particle therapy will be needed during the next years to help to thoroughly evaluate the high potential of ion therapy.

Neurocognitive Function Following Therapy for Low-Grade Gliomas

Low-grade gliomas (LGGs) are a heterogenous group of primary brain neoplasms that most commonly occur in children and young adults, characterized by a slow, indolent course and overall favorable prognosis. Standard therapies used to treat LGGs have included surgical resection, radiotherapy, chemotherapy, or a combination thereof. Given the anticipated long survival and typical young age of patients with LGG, the long-term sequelae of therapy require special attention, especially as they affect neurocognitive function and quality of life. We review the complex interplay of baseline and treatment-related factors that perturb neurocognition as well as the effect of each treatment modality on altering neurocognitive outcomes in this patient population.

Quality of life of children and adolescents with cancer: revision of studies literature that used the Pediatric Quality Of Life Inventory

OBJECTIVE

To assess the quality of life of children and adolescents with cancer of studies that applied the Pediatric Quality of Life Inventory 3.0 Cancer Module.

METHODOLOGY

The study was carried out on the basis of data Scopus Web of Science, BIREME, EBSCO host and Psychoinfo of articles in Spanish, English and Portuguese, and published from 1998 to 2013 that used the Pediatric Quality of life Inventory 3.0 Cancer Module.

RESULTS

21 articles were selected, of which 47.6% were carried out in America, and 61.9% of editions comprehended from 2011 to 2013. The scores variation by dimensions and in general was probably related for the selection of comparison groups, as the diversity of inclusion criteria and variants may be observed for the analysis in each study. The existence of a standard dimension could not be verified either for children ́s /adolescents reports or for parents.

CONCLUSION

It is concluded that the scores averages by dimensions in general have not achieved values below 30 and the largest scores by dimension are above 80. It is suggested that the treatment anxiety dimension in children ́s and adolescents ́s reports may have obtained the largest scores within each study, that is lesser than the difficulty of the children and adolescents in face of the treatment and cancer. Nursing becomes a constant presence in the life of children and adolescents with cancer and it may provide a better quality of life for developing nursing activities and the team may demistify, clarify and help in all phases of the illness and treatment.

Protons and more: state of the art in radiotherapy

The purpose of modern radiotherapy is to deliver a precise high dose of radiation which will result in reproductive death of the cells. Radiation should transverse within the tumour volume whilst minimising damage to surrounding normal tissue. Overall 40% of cancers which are cured will have received radiotherapy. Current state of the art treatment will incorporate cross-sectional imaging and multiple high energy X-ray beams in processes called intensity modulated radiotherapy and image guided radiotherapy. Brachytherapy enables very high radiation doses to be delivered by the direct passage of a radiation source through or within the tumour volume and similar results can be achieved using rotational stereotactic X-ray beam techniques. Protons have the characteristics of particle beams which deposit their energy in a finite fixed peak at depth in tissue with no dose beyond this point - the Bragg peak. This has advantages in certain sites such as the spine adjacent to the spinal cord and particularly in children when the overall volume of tissue receiving radiation can be minimised.

Socio-economic factors affect the outcome of soft tissue sarcoma: an analysis of SEER data

BACKGROUND

This study analyzed whether socio-economic factors affect the cause specific survival of soft tissue sarcoma (STS).

METHODS

Surveillance, Epidemiology and End Results (SEER) soft tissue sarcoma (STS) data were used to identify potential socio-economic disparities in outcome. Time to cause specific death was computed with Kaplan-Meier analysis. Kolmogorov-Smirnov tests and Cox proportional hazard analysis were used for univariate and multivariate tests, respectively. The areas under the receiver operating curve were computed for predictors for comparison.

RESULTS

There were 42,016 patients diagnosed STS from 1973 to 2009. The mean follow up time (S.D.) was 66.6 (81.3) months. Stage, site, grade were significant predictors by univariate tests. Race and rural-urban residence were also important predictors of outcome. These five factors were all statistically significant with Cox analysis. Rural and African-American patients had a 3-4% disadvantage in cause specific survival.

CONCLUSIONS

Socio-economic factors influence cause specific survival of soft tissue sarcoma. Ensuring access to cancer care may eliminate the outcome disparities.

Quality of life outcomes in proton and photon treated pediatric brain tumor survivors

BACKGROUND

Radiotherapy can impair Health Related Quality of Life (HRQoL) in survivors of childhood brain tumors, but proton radiotherapy (PRT) may mitigate this effect. This study compares HRQoL in PRT and photon (XRT) pediatric brain tumor survivors.

METHODS

HRQoL data were prospectively collected on PRT-treated patients aged 2-18 treated at Massachusetts General Hospital (MGH). Cross-sectional PedsQL data from XRT treated Lucile Packard Children's Hospital (LPCH) patients provided the comparison data.

RESULTS

Parent proxy HRQoL scores were reported at 3 years for the PRT cohort (PRT-C) and 2.9 years (median) for the XRT cohort (XRT-C). The total core HRQoL score for the PRT-C, XRT-C, and normative population differed from one another and was 75.9, 65.4 and 80.9 respectively (p=0.002; p=0.024; p<0.001). The PRT-C scored 10.3 and 10.5 points higher than the XRT-C in the physical (PhSD) and psychosocial (PsSD) summary domains of the total core score (TCS, p=0.015; p=0.001). The PRT-C showed no difference in PhSD compared with the normative population, but scored 6.1 points less in the PsSD (p=0.003). Compared to healthy controls, the XRT-C scored lower in all domains (p<0.001).

CONCLUSIONS

The HRQoL of pediatric brain tumor survivors treated with PRT compare favorably to those treated with XRT and similar to healthy controls in the PhSD.

Child-related characteristics predicting subsequent health-related quality of life in 8- to 14-year-old children with and without cerebellar tumors: a prospective longitudinal study

BACKGROUND

We identified child-related determinants of health-related quality of life (HRQoL) in children aged 8-14 years who were treated for 2 common types of pediatric brain tumors.

METHODS

Questionnaire measures of HRQoL and psychometric assessments were completed by 110 children on 3 occasions over 24 months. Of these 110, 72 were within 3 years of diagnosis of a cerebellar tumor (37 standard-risk medulloblastoma, 35 low-grade cerebellar astrocytoma), and 38 were in a nontumor group. HRQoL, executive function, health status, and behavioral difficulties were also assessed by parents and teachers as appropriate. Regression modeling was used to relate HRQoL z scores to age, sex, socioeconomic status, and 5 domains of functioning: Cognition, Emotion, Social, Motor and Sensory, and Behavior.

RESULTS

HRQoL z scores were significantly lower after astrocytoma than those in the nontumor group and significantly lower again in the medulloblastoma group, both by self-report and by parent-report. In regression modeling, significant child-related predictors of poorer HRQoL z scores by self-report were poorer cognitive and emotional function (both z scores) and greater age (years) at enrollment (B = 0.038, 0.098, 0.136, respectively). By parent-report, poorer cognitive, emotional and motor or sensory function (z score) were predictive of lower subsequent HRQoL of the child (B = 0.043, 0.112, 0.019, respectively), while age at enrollment was not.

CONCLUSIONS

Early screening of cognitive and emotional function in this age group, which are potentially amenable to change, could identify those at risk of poor HRQoL and provide a rational basis for interventions to improve HRQoL.

Underusage of radiotherapy and a lack of socio-economic disparity in treatment outcome: a population-based study on adenoid cystic carcinomas

This study used receiver operating characteristic curve to analyse a long list of biological, treatment and socio-economic predictors of adenoid cystic carcinoma treatment outcome. Anatomical staging was found to be the most predictive factor of outcome.

Purpose

This study used receiver operating characteristic curve (ROC) to analyse surveillance, epidemiology and end results (SEER) adenoid cystic carcinoma data to identify predictive models and potential disparity in outcome.

Materials and methods

For the risk modelling, each factor was fitted by a generalised linear model to predict the cause-specific survival. The area under the ROC was computed. Similar strata were combined to construct the most parsimonious models. A random sampling algorithm was used to estimate the modelling errors. Risk of adenoid cystic carcinoma death was computed for the predictors for comparison.

Results

There were 5,947 patients diagnosed from 1973 to 2009 included in this study. The mean follow-up time (SD) was 93·8 (90·6) months. Three out of five patients were women. The mean (SD) age was 58·55 (16·01) years. SEER stage was the most predictive factor of outcome (ROC area of 0·68). Sex, radiotherapy and surgery had ROC areas of about 0·57. None of the socio-economic disparities was found for treatment outcome. Radiotherapy was underused in localised and regional stages when the intent was curative, especially in older patients.

Conclusion

Anatomical staging was predictive and useful in treatment selection. Understaging and underuse of radiotherapy may have contributed to poor outcomes.

Proton therapy for the treatment of children with CNS malignancies

Proton therapy is a novel technique for treating pediatric malignancies. As a tool to reduce normal-tissue dose, it has the potential to decrease late toxicity. Although proton therapy has been used for over five decades, most pediatric dosimetry studies and clinical series have been published over the last 10 years. The purpose of this article is to review the physical, radiobiological and economic rationales for proton therapy in pediatric CNS malignancies, and provide an overview of the current challenges and future direction of research and utilization of this approach.

Pediatric low-grade gliomas: how modern biology reshapes the clinical field

Low-grade gliomas represent the most frequent brain tumors arising during childhood. They are characterized by a broad and heterogeneous group of tumors that are currently classified by the WHO according to their morphological appearance. Here we review the clinical features of these tumors, current therapeutic strategies and the recent discovery of genomic alterations characteristic to these tumors. We further explore how these recent biological findings stand to transform the treatment for these tumors and impact the diagnostic criteria for pediatric low-grade gliomas.

Surveying and optimizing the predictors for ependymoma specific survival using SEER data

PURPOSE

This study used receiver operating characteristic curve to analyze Surveillance, Epidemiology and End Results (SEER) ependymoma data to identify predictive models and potential disparity in outcome.

MATERIALS AND METHODS

This study analyzed socio-economic, staging and treatment factors available in the SEER database for ependymoma. For the risk modeling, each factor was fitted by a Generalized Linear Model to predict the outcome ('brain and other nervous systems' specific death in yes/no). The area under the receiver operating characteristic curve (ROC) was computed. Similar strata were combined to construct the most parsimonious models. A random sampling algorithm was used to estimate the modeling errors. Risk of ependymoma death was computed for the predictors for comparison.

RESULTS

A total of 3,500 patients diagnosed from 1973 to 2009 were included in this study. The mean follow up time (S.D.) was 79.8 (82.3) months. Some 46% of the patients were female. The mean (S.D.) age was 34.4 (22.8) years. Age was the most predictive factor of outcome. Unknown grade demonstrated a 15% risk of cause specific death compared to 9% for grades I and II, and 36% for grades III and IV. A 5-tiered grade model (with a ROC area 0.48) was optimized to a 3-tiered model (with ROC area of 0.53). This ROC area tied for the second with that for surgery. African-American patients had 21.5% risk of death compared with 16.6% for the others. Some 72.7% of patient who did not get RT had cerebellar or spinal ependymoma. Patients undergoing surgery had 16.3% risk of death, as compared to 23.7% among those who did not have surgery.

CONCLUSION

Grading ependymoma may dramatically improve modeling of data. RT is under used for cerebellum and spinal cord ependymoma and it may be a potential way to improve outcome.

Technique, outcomes, and acute toxicities in adults treated with proton beam craniospinal irradiation

BACKGROUND

Proton craniospinal irradiation (p-CSI) has been proposed to reduce side effects associated with CSI. We evaluated acute toxicities and preliminary clinical outcomes in a series of adults treated with p-CSI.

METHODS

We reviewed medical records for 50 patients (aged 16-63 y) with malignancies of varying histologies treated consecutively with vertebral body-sparing p-CSI at MD Anderson Cancer Center from 2007 to 2011. Median CSI and total boost doses were 30.6 and 54 Gy. Forty patients received chemotherapy, varying by histology. Median follow-up was 20.1 months (range, 0.3-59).

RESULTS

Median doses to the thyroid gland, pituitary gland, hypothalamus, and cochleae were 0.003 Gy-relative biological effectiveness (RBE; range, 0.001-8.5), 36.1 Gy-RBE (22.5-53.0), 37.1 Gy-RBE (22.3-54.4), and 33.9 Gy-RBE (22.2-52.4), respectively. Median percent weight loss during CSI was 1.6% (range, 10% weight loss to 14% weight gain). Mild nausea/vomiting was common (grade 1 = 46%, grade 2 = 20%); however, only 5 patients experienced grade ≥2 anorexia (weight loss >5% baseline weight). Median percent baseline white blood cells, hemoglobin, and platelets at nadir were 52% (range, 13%-100%), 97% (65%-112%), and 61% (10%-270%), respectively. Four patients developed grade ≥3 cytopenias. Overall and progression-free survival rates were 96% and 82%, respectively, at 2 years and 84% and 68% at 5 years.

CONCLUSIONS

This large series of patients treated with p-CSI confirms low rates of acute toxicity, consistent with dosimetric models. Vertebral body-sparing p-CSI is feasible and should be considered as a way to reduce acute gastrointestinal and hematologic toxicity in adults requiring CSI.

Vision specific quality of life in children with optic pathway gliomas

Children with optic pathway gliomas (OPGs) frequently experience vision loss from their tumors. Most pediatric OPG research has focused on radiographic and visual outcomes, yet the impact of vision loss on quality of life (QOL) in children with OPGs has not been studied. The present study prospectively recruited children ≤ 10 years of age with sporadic or neurofibromatosis type 1 (NF1)-related OPGs. Vision specific QOL was assessed by parent proxy using the Children's Visual Function Questionnaire (CVFQ), and scores were analyzed according to magnitude of visual acuity (VA) loss and presence of visual field (VF) loss. Thirty-six subjects completed the study (53 % female) with median age of 4.6 years. Children with mild, moderate and severe vision loss have lower CVFQ subscale scores, indicating a lower vision specific QOL, compared to those with normal vision. Lower Competence scores were noted in participants with more profound vision loss (p < 0.05), reflecting a decreased ability to complete activities of daily living (e.g., feeding, grooming). Children with two visually impaired eyes were rated as having greater difficulty with social interactions and pleasurable activities (Personality subscale, p = 0.039) compared to those with only one impaired eye. In summary, our findings demonstrate that children with vision loss secondary to their OPG have a decreased vision specific QOL compared to those with normal vision. Measuring vision specific QOL may be considered a meaningful secondary outcome measure for pediatric OPG clinical trials.

New strategies in radiation therapy: exploiting the full potential of protons

Protons provide significant dosimetric advantages compared with photons because of their unique depth-dose distribution characteristics. However, they are more sensitive to the effects of intra- and intertreatment fraction anatomic variations and uncertainties in treatment setup. Furthermore, in the current practice of proton therapy, the biologic effectiveness of protons relative to photons is assumed to have a generic fixed value of 1.1. However, this is a simplification, and it is likely higher in different portions of the proton beam. Current clinical practice and trials have not fully exploited the unique physical and biologic properties of protons. Intensity-modulated proton therapy, with its ability to manipulate energies (in addition to intensities), provides an entirely new dimension, which, with ongoing research, has considerable potential to increase the therapeutic ratio.

Natural history and role of radiation in patients with supratentorial and infratentorial WHO grade II ependymomas: results from a population-based study

Patients with World Health Organization (WHO) grade II supratentorial ependymomas are commonly observed after gross total resection (GTR), although supporting data are limited. We sought to characterize the natural history of such tumors. We used the Surveillance, Epidemiology, and End Results program to identify 112 patients ages 0-77 diagnosed with WHO grade II ependymomas between 1988 and 2007, of whom 63 (56 %) and 49 (44 %) had supratentorial and infratentorial primaries, respectively. Inclusion criteria were strict to ensure patient homogeneity. Of 33 patients with supratentorial tumors after GTR, 18 (55 %) received adjuvant radiation therapy and 15 (45 %) did not. Ependymoma-specific mortality (ESM) was the primary endpoint. With a median follow up of 4.5 years, only 1 of 33 patients with supratentorial ependymoma died of their disease after GTR; the 5-year estimate of ESM in this population was 3.3 % (95 % CI 0.2-14.8 %). Among patients with infratentorial ependymomas after GTR, the 5-year estimate of ESM was 8.7 % (95 % CI 1.4-24.6 %). In patients with subtotally resected tumors, 5-year estimates of ESM in patients with supratentorial and infratentorial primaries were 20.1 % (95 % CI 8.0-36.2 %) and 12.3 % (95 % CI 2.9-28.8 %), respectively. Among the whole cohort, on both univariable and multivariable regression, extent of resection was predictive of ESM, while tumor location and use of radiation were not. After GTR, patients with WHO grade II supratentorial ependymomas have a very favorable natural history with low associated cancer-specific mortality. Observation, with radiation reserved as a salvage option, may be a reasonable postoperative strategy in this population.

Dosimetric impact of reduced nozzle-to-isocenter distance in intensity-modulated proton therapy of intracranial tumors in combined proton-carbon fixed-nozzle treatment facilities

Background

In combined proton-carbon fixed-nozzle treatment facilities with raster scanning delivery, the scattering of proton pencil beams caused by nozzle elements and the relatively large nozzle-to-isocenter distance cause a beam broadening. This may pose limitations to the achievable dose conformity. One way to counteract this effect is by delivering the treatment in a position closer to the nozzle than the room isocenter. Purpose of this study was to assess the potential dosimetric benefit of such solution, in terms of dose conformity and normal tissue sparing, in intensity-modulated proton therapy (IMPT) of intracranial tumors.

Material and methods

For 12 patients with intracranial lesions, IMPT-plans were created at two treatment positions: nozzle-to-treatment-isocenter distance: 100 cm (room isocenter) and nozzle-to-treatment-isocenter distance: 60 cm. The resulting plans were compared in terms of dose distributions, dose-volume histograms and selected dosimetric indexes.

Results

With comparable target coverage, statistically significant normal tissue sparing was achieved through the reduction of the distance between nozzle and treatment isocenter. The decrease in mean dose (D_mean) was 12.5% to the whole brain, 16.2% to the brainstem, 9.7% and 15.4% to the temporal lobes, 10.0% and 12.9% to the hippocampi, 11.8% and 12.5% to the optic nerves and 0.2% to the chiasm. The volume receiving at least 10% of the prescribed dose (V_10%) was reduced by more than 10% for most organs at risk (OARs). The maximum dose (D_near-max) values to most OARs remained without significant difference.

Conclusion

A reduced distance between nozzle and treatment isocenter leads to steeper lateral dose gradients and significantly reduces the volume of OARs adjacent to the target, which receives low to intermediate doses. Technical solutions shifting the treatment isocenter closer to the nozzle should be considered in clinical situations, where critical OARs are adjacent to the beam channel and where the integral dose should be minimized.

Acute toxicity of proton beam radiation for pediatric central nervous system malignancies

BACKGROUND

Proton beam therapy (PBT) for pediatric CNS malignancies may reduce late toxicity, but acute toxicity is not well defined. We examined acute toxicity for children with CNS malignancies treated with PBT.

PROCEDURE

We conducted a retrospective review of 48 children with malignant brain tumors treated with PBT at our facility from 2010 to 2012. For each patient, we recorded age at diagnosis, tumor location, histologic subtype, radiation dose, extent of radiation, and use of concurrent chemotherapy. Acute toxicity scores were recorded per the National Cancer Institute Common Terminology Criteria for Adverse Events version 4.0 at weekly on treatment visits. Maximum grade of fatigue, headache, insomnia, anorexia, nausea, vomiting, alopecia, and dermatitis over the radiation therapy treatment course were recorded, and rates of acute toxicity were calculated.

RESULTS

The cohort consisted of 16 glial tumors, 9 medulloblastomas, 6 germinomas, 5 ependymomas, 4 craniopharyngiomas, 3 atypical teratoid rhabdoid tumors, and 5 other CNS tumors. The mean age was 10.8 years, and median dose was 5,400 cGy (RBE). Acute toxicities were generally low-grade and manageable. The most commonly observed acute toxicities were fatigue, alopecia, and dermatitis. The least common were insomnia and vomiting. Higher maximum grades for headache, nausea, and vomiting over the treatment course were associated with infratentorial location, while higher maximum grades for anorexia, nausea, and alopecia were associated with craniospinal radiation.

CONCLUSIONS

PBT appears to be well tolerated in pediatric patients with CNS malignancies. Acute toxicity can be managed with supportive care.

Poor treatment outcome of neuroblastoma and other peripheral nerve cell tumors may be related to under usage of radiotherapy and socio-economic disparity: a US SEER data analysis

PURPOSE

This study used receiver operating characteristic curve to analyze Surveillance, Epidemiology and End Results (SEER) neuroblastoma (NB) and other peripheral nerve cell tumors (PNCT) outcome data. This study found under usage of radiotherapy in these patients.

MATERIALS AND METHODS

This study analyzed socio-economic, staging and treatment factors available in the SEER database for NB and other PNCT. For the risk modeling, each factor was fitted by a generalized jinear model to predict the outcome (soft tissue specific death, yes/no). The area under the receiver operating characteristic curve (ROC) was computed. Similar strata were combined to construct the most parsimonious models. A random sampling algorithm was used to estimate the modeling errors. Risk of neuroendocrine (other endocrine including thymus as coded in SEER) death was computed for the predictors.

RESULTS

There were 5261 patients diagnosed from 1973 to 2009 were included in this study. The mean follow up time (S.D.) was 83.8 (97.6) months. The mean (SD) age was 18 (25) years. About 30.45% of patients were un-staged. The SEER staging has high ROC (SD) area of 0.58 (0.01) among the factors tested. We simplified the 4-layered risk levels (local, regional, distant, un-staged/others) to a simpler 3-tiered model with comparable ROC area of 0.59 (0.01). Less than 50% of PNCT patients received radiotherapy (RT) including the ones with localized disease. This avoidance of RT use occurred in adults and children.

CONCLUSION

The high under-staging rate may have prevented patients from selecting definitive radiotherapy (RT) after surgery. Using RT for, especially, adult PNCT patients is a potential way to improve outcome.

Charged particle therapy--optimization, challenges and future directions

The use of charged particle therapy to control tumours non-invasively offers advantages over conventional radiotherapy. Protons and heavy ions deposit energy far more selectively than X-rays, allowing a higher local control of the tumour, a lower probability of damage to healthy tissue, low risk of complications and the chance for a rapid recovery after therapy. Charged particles are also useful for treating tumours located in areas that surround tissues that are radiosensitive and in anatomical sites where surgical access is limited. Current trial outcomes indicate that accelerated ions can potentially replace surgery for radical cancer treatments, which might be beneficial as the success of surgical cancer treatments are largely dependent on the expertise and experience of the surgeon and the location of the tumour. However, to date, only a small number of controlled randomized clinical trials have made comparisons between particle therapy and X-rays. Therefore, although the potential advantages are clear and supported by data, the cost:benefit ratio remains controversial. Research in medical physics and radiobiology is focusing on reducing the costs and increasing the benefits of this treatment.

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.

Past, present, and future of radiotherapy for the benefit of patients

Radiotherapy has been driven by constant technological advances since the discovery of X-rays in 1895. Radiotherapy aims to sculpt the optimal isodose on the tumour volume while sparing normal tissues. The benefits are threefold: patient cure, organ preservation and cost-efficiency. The efficacy and tolerance of radiotherapy were demonstrated by randomized trials in many different types of cancer (including breast, prostate and rectum) with a high level of scientific evidence. Such achievements, of major importance for the quality of life of patients, have been fostered during the past decade by linear accelerators with computer-assisted technology. More recently, these developments were augmented by proton and particle beam radiotherapy, usually combined with surgery and medical treatment in a multidisciplinary and personalized strategy against cancer. This article reviews the timeline of 100 years of radiotherapy with a focus on breakthroughs in the physics of radiotherapy and technology during the past two decades, and the associated clinical benefits.

Baby Steps to Superintelligence: Neuroprosthetics and Children

Children surviving neural injuries face challenges not seen by their adult counterparts, namely that they experience neural injury before reaching neurodevelopmental maturity. Neural prostheses offer one possible path to recovery, along with the potential for functional outcomes that could exceed expectations. Although the first cochlear implant was placed more than fifty years ago, the field of neuroprosthetics is still relatively young. Several types of neural prostheses are in development stages ranging from animal models to (adult) human trials. In this paper, I discuss how neural prostheses may assist recovery for children surviving neural injury. I argue that approaching the use of neural prosthetics in children with considerations derived from transhumanism alongside traditional bioethics can provide an opportunity to reframe adult-focused ethics toward a child/family focus and to strip away the prejudicial metaphor of cyborgization.