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OBJECTIVE: Sleep is a complex neurologic process that is generated by and primarily benefits the brain. Sleep can be disrupted by a wide range of brain injuries, many of which may occur in children with neoplasms of the central nervous system (CNS). The specific sleep problems that have been associated with brain injuries include sleepiness, apnea, insomnia, and loss of circadian rhythmicity. The objective of this study was to characterize the sleep problems seen in children with neoplasms of the CNS through a comprehensive clinical and objective sleep evaluation. METHODS: A retrospective case series review was conducted of all children with neoplasms of the CNS referred to the sleep clinic for a clinical evaluation between 1994 and 2002. The sleep evaluation of the 14 children in this report included a sleep history, a sleep log, and a polysomnogram. In the 12 children with complaints of daytime sleepiness and/or fatigue, a multiple sleep latency test was performed the day after the polysomnogram. Three children also had a 2-week actigraphic study. RESULTS: The most common sleep complaint in this group of children was excessive daytime sleepiness (EDS), present in 9 of the 14 children. In these children, the sleepiness was manifest by 1 or more of the following symptoms: 1) an increase in total sleep time per 24 hours; 2) the resumption of daytime naps that had been previously discontinued at a younger age; 3) an inability to awaken in the morning to begin the days activities; or 4) the inability to remain awake during activities of daily living, such as school. Of the 9 children with daytime sleepiness, 8 had brain tumors requiring neurosurgical procedures at the time of their diagnosis, 6 of whom required ventricular shunting. The children with the most severe sleepiness had evidence of hypothalamic/pituitary injury with deficiencies in both anterior and posterior pituitary hormones. Five of the children with EDS had polysomnographic evidence of symptomatic narcolepsy with rapid eye movement sleep present on 2 or more of the daytime naps. The symptoms of EDS were effectively controlled with modest doses of daytime stimulant medication and/or scheduled naps. Central apnea leading to respiratory insufficiency and requiring mechanical ventilation to correct was present in 2 children with tumors involving the medulla. Although snoring with possible obstructive sleep apnea was the reason for referral to the sleep clinic in 5 children, none of the children in this series had polysomnographic evidence of significant obstructive sleep apnea. The other sleep problems seen in these children were hypoxia in 2 children, fatigue in 3 children, and seizures during sleep in 1 child. The interval between tumor diagnosis and sleep evaluation varied from 0 months to 9 years (mean: 42 months). The treatment of the sleep problems of this group of children took many forms, including stimulants, scheduled naps, mechanical ventilation, supplemental oxygen, and anticonvulsants. CONCLUSIONS: Brain injuries, which invariably are present in children with neoplasms of the CNS, may result in a variety of diagnosable and treatable sleep disorders. The sleep symptoms did not appear to be directly related to the specific therapy the child received, nor the presence of residual tumor. Rather, the primary determinant of the sleep symptoms was the area of the brain that was damaged, regardless of how the damage occurred. Children who sustained damage to the hypothalamic/pituitary region developed EDS regardless of whether the damage was the result of the tumor, surgery, hydrocephalus, or radiation to the whole brain or localized to the suprasellar area. The only children who developed respiratory insufficiency had an injury to the medulla. This observation is consistent with the view that sleep is a specific, albeit complex, neurologic process that is controlled by specific brain regions. EDS and respiratory insufficiency were the most commonly diagnosed severe sleep disorders in these children. The sleep problems of children with brain tumors may develop before, but more often soon after, their tumor diagnosis and treatment. However, the sleep symptoms may not be appreciated by medical providers until years after their onset, which may delay the beginning of effective interventions. [ABSTRACT FROM AUTHOR]

The concept of oncocytoid renal cell carcinoma in patients who have survived neuroblastoma as a distinct biologic entity has been controversial since its original description in 1999. This is in part because similar oncocytoid renal cell carcinomas have been described in association with other pediatric cancers, and also because other renal cell carcinoma subtypes (such as MiT family translocation renal cell carcinoma) have been described in children who have survived neuroblastoma. We identified an index case of a child who survived medulloblastoma and developed multifocal bilateral oncocytoid renal cell carcinomas with morphology and immunophenotype compatible with eosinophilic solid and cystic renal cell carcinoma (ESC RCC) and demonstrated that both neoplasms harbored distinctive mutations in the TSC1/TSC2 genes. Remarkably, the child's remaining bilateral multifocal renal neoplasms completely responded to MTOR inhibitor therapy without need for further surgery. To confirm our hypothesis that oncocytoid renal cell carcinomas after childhood cancer represent ESC RCC, we obtained formalin-fixed paraffin-embedded tissue blocks from 2 previously published cases of oncocytoid renal cell carcinoma after neuroblastoma, confirmed that the morphology and immunophenotype was consistent with ESC RCC, and demonstrated that both cases harbored somatic TSC gene mutations. Both expressed markers previously associated with neoplasms harboring TSC gene mutations, glycoprotein nonmetastatic B, and cathepsin K. Of note, one of these patients had 2 ESC RCC which harbored distinctive TSC2 mutations, while the background kidney of the other patient had multiple small cysts lined by similar oncocytoid cells which showed loss of TSC2 protein. We then reviewed 3 of 4 cases from the original 1999 report of oncocytoid renal cell carcinomas after neuroblastoma, found that all 3 demonstrated morphology (including basophilic cytoplasmic stippling) that is characteristic of ESC RCC, showed that all 3 overexpressed glycoprotein nonmetastatic B, and showed that both cases with adequate material demonstrated loss of TSC2 protein and expressed cytokeratin 20 and cathepsin K by immunohistochemistry. In summary, "oncocytoid renal cell carcinomas after neuroblastoma" represent ESC RCC which are often multifocal in patients who have survived childhood cancer, likely representing an incompletely characterized tumor predisposition syndrome. MTOR-targeted therapy represents an effective therapeutic option for such patients to preserve functional nephrons., Competing Interests: Conflicts of Interest and Source of Funding: Supported in part by: Dahan Translocation Carcinoma Fund (P.A.) and Joey’s Wings (P.A.). The authors have disclosed that they have no significant relationships with, or financial interest in, any commercial companies pertaining to this article., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Recurrent atypical teratoid/rhabdoid tumor (AT/RT) is, most often, a fatal pediatric malignancy with limited curative options., Methods: We conducted a phase II study of Aurora kinase A inhibitor alisertib in patients aged <22 years with recurrent AT/RT. Patients received alisertib once daily (80 mg/m2 as enteric-coated tablets or 60 mg/m2 as liquid formulation) on Days 1-7 of a 21-day cycle until progressive disease (PD) occurred. Alisertib plasma concentrations were measured in cycle 1 on Days 1 (single dose) and 7 (steady state) and analyzed with noncompartmental pharmacokinetics. Trial efficacy end point was ≥10 participants with stable disease (SD) or better at 12 weeks., Results: SD (n = 8) and partial response (PR) (n = 1) were observed among 30 evaluable patients. Progression-free survival (PFS) was 30.0% ± 7.9% at 6 months and 13.3% ± 5.6% at 1 year. One-year overall survival (OS) was 36.7% ± 8.4%. Two patients continued treatment for >12 months. PFS did not differ by AT/RT molecular groups. Neutropenia was the most common adverse effect (n = 23/30, 77%). The 22 patients who received liquid formulation had a higher mean maximum concentration (Cmax) of 10.1 ± 3.0 µM and faster time to Cmax (Tmax = 1.2 ± 0.7 h) than those who received tablets (Cmax = 5.7 ± 2.4 µM, Tmax = 3.4 ± 1.4 h)., Conclusions: Although the study did not meet predetermined efficacy end point, single-agent alisertib was well tolerated by children with recurrent AT/RT, and SD or PR was observed in approximately a third of the patients., (© The Author(s) 2022. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Purpose: Report relevance of molecular groups to clinicopathologic features, germline SMARCB1/SMARCA4 alterations (GLA), and survival of children with atypical teratoid rhabdoid tumor (ATRT) treated in two multi-institutional clinical trials., Materials and Methods: Seventy-four participants with newly diagnosed ATRT were treated in two trials: infants (SJYC07: age < 3 years; n = 52) and children (SJMB03: age 3-21 years; n = 22), using surgery, conventional chemotherapy (infants), or dose-dense chemotherapy with autologous stem cell rescue (children), and age- and risk-adapted radiotherapy [focal (infants) and craniospinal (CSI; children)]. Molecular groups ATRT-MYC (MYC), ATRT-SHH (SHH), and ATRT-TYR (TYR) were determined from tumor DNA methylation profiles., Results: Twenty-four participants (32%) were alive at time of analysis at a median follow-up of 8.4 years (range, 3.1-14.1 years). Methylation profiling classified 64 ATRTs as TYR ( n = 21), SHH ( n = 30), and MYC ( n = 13), SHH group being associated with metastatic disease. Among infants, TYR group had the best overall survival (OS; P = 0.02). However, outcomes did not differ by molecular groups among infants with nonmetastatic (M0) disease. Children with M0 disease and <1.5 cm 2 residual tumor had a 5-year progression-free survival (PFS) of 72.7 ± 12.7% and OS of 81.8 ± 11%. Infants with M0 disease had a 5-year PFS of 39.1 ± 11.5% and OS of 51.8 ± 12%. Those with metastases fared poorly [5-year OS 25 ± 12.5% (children) and 0% (infants)]. SMARCB1 GLAs were not associated with PFS., Conclusions: Among infants, those with ATRT-TYR had the best OS. ATRT-SHH was associated with metastases and consequently with inferior outcomes. Children with nonmetastatic ATRT benefit from postoperative CSI and adjuvant chemotherapy., (©2021 American Association for Cancer Research.)

Purpose: We sought to investigate clinical outcomes of relapsed medulloblastoma and to compare molecular features between patient-matched diagnostic and relapsed tumors., Methods: Children and infants enrolled on either SJMB03 (NCT00085202) or SJYC07 (NCT00602667) trials who experienced medulloblastoma relapse were analyzed for clinical outcomes, including anatomic and temporal patterns of relapse and postrelapse survival. A largely independent, paired molecular cohort was analyzed by DNA methylation array and next-generation sequencing., Results: A total of 72 of 329 (22%) SJMB03 and 52 of 79 (66%) SJYC07 patients experienced relapse with significant representation of Group 3 and wingless tumors. Although most patients exhibited some distal disease (79%), 38% of patients with sonic hedgehog tumors experienced isolated local relapse. Time to relapse and postrelapse survival varied by molecular subgroup with longer latencies for patients with Group 4 tumors. Postrelapse radiation therapy among previously nonirradiated SJYC07 patients was associated with long-term survival. Reirradiation was only temporizing for SJMB03 patients. Among 127 patients with patient-matched tumor pairs, 9 (7%) experienced subsequent nonmedulloblastoma CNS malignancies. Subgroup (96%) and subtype (80%) stabilities were largely maintained among the remainder. Rare subgroup divergence was observed from Group 4 to Group 3 tumors, which is coincident with genetic alterations involving MYC , MYCN , and FBXW7 . Subgroup-specific patterns of alteration were identified for driver genes and chromosome arms., Conclusion: Clinical behavior of relapsed medulloblastoma must be contextualized in terms of up-front therapies and molecular classifications. Group 4 tumors exhibit slower biological progression. Utility of radiation at relapse is dependent on patient age and prior treatments. Degree and patterns of molecular conservation at relapse vary by subgroup. Relapse tissue enables verification of molecular targets and identification of occult secondary malignancies.

Atypical teratoid/rhabdoid tumors (ATRTs) are very aggressive childhood malignancies of the central nervous system. The underlying genetic cause are inactivating bi-allelic mutations in SMARCB1 or (rarely) in SMARCA4. ATRT-SMARCA4 have been associated with a higher frequency of germline mutations, younger age, and an inferior prognosis in comparison to SMARCB1 mutated cases. Based on their DNA methylation profiles and transcriptomics, SMARCB1 mutated ATRTs have been divided into three distinct molecular subgroups: ATRT-TYR, ATRT-SHH, and ATRT-MYC. These subgroups differ in terms of age at diagnosis, tumor location, type of SMARCB1 alterations, and overall survival. ATRT-SMARCA4 are, however, less well understood, and it remains unknown, whether they belong to one of the described ATRT subgroups. Here, we examined 14 ATRT-SMARCA4 by global DNA methylation analyses. We show that they form a separate group segregating from SMARCB1 mutated ATRTs and from other SMARCA4-deficient tumors like small cell carcinoma of the ovary, hypercalcemic type (SCCOHT) or SMARCA4 mutated extra-cranial malignant rhabdoid tumors. In contrast, medulloblastoma (MB) samples with heterozygous SMARCA4 mutations do not group separately, but with established MB subgroups. RNA sequencing of ATRT-SMARCA4 confirmed the clustering results based on DNA methylation profiling and displayed an absence of typical signature genes upregulated in SMARCB1 deleted ATRT. In summary, our results suggest that, in line with previous clinical observations, ATRT-SMARCA4 should be regarded as a distinct molecular subgroup.

Background: Children with high-grade CNS cancers frequently experience malnutrition during treatment. We assessed the effects of proactive enteral tube (ET) placement/enteral tube feedings (ETF) on weight in infants/children with high-grade CNS tumors treated with aggressive chemotherapy., Methods: We conducted a retrospective study of patients age 0 to 19 years treated for new high-grade CNS tumors between 2002 and 2017 at a tertiary pediatric hospital system. Patients underwent placement of proactive ET (≤ 31 days postdiagnosis; n = 45), rescue ET (> 31 days, due to weight loss; n = 9), or no ET (n = 18). Most received surgically placed ET (98%), with percutaneous endoscopic gastrojejunostomy or gastrojejunostomy tubes favored to allow jejunal feeding. The majority of patients with ET used ETF (91%). Using mixed-effects regression models, we examined differences in mean weights between ET/ETF groups across the first year of treatment. We also evaluated observed weight changes., Results: All infants (n = 22, median age, 1.5 years) had proactive ET placed and 21 of 22 used proactive ETF. Infants showed an initial increase in mean percentage weight change that eventually leveled off, for an estimated increase of 10.4% over the year. For the pediatric cohort (n = 50, median, 8.1 years), those receiving proactive ETF experienced weight increases (+9.9%), those with rescue ETF experienced an initial decline and eventually rebounded for no net change (0.0%), and those with no ETF demonstrated an initial decline that persisted (-11.9%; P interaction < .001). Analysis of observed weights revealed nearly identical patterns., Conclusions: Proactive ETF was effective at maintaining weight and/or facilitating weight gain over the first year of treatment and was acceptable to patients/families., (© The Author(s) 2020. Published by Oxford University Press on behalf of the Society for Neuro-Oncology and the European Association of Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: This report documents the clinical characteristics, molecular grouping, and outcome of young children with ependymoma treated prospectively on a clinical trial., Methods: Fifty-four children (aged ≤3 y) with newly diagnosed ependymoma were treated on the St Jude Young Children 07 (SJYC07) trial with maximal safe surgical resection, 4 cycles of systemic chemotherapy, consolidation therapy using focal conformal radiation therapy (RT) (5-mm clinical target volume), and 6 months of oral maintenance chemotherapy. Molecular groups were determined by tumor DNA methylation using Infinium Methylation EPIC BeadChip and profiled on the German Cancer Research Center/Molecular Neuropathology 2.0 classifier., Results: One of the 54 study patients had metastases (cerebrospinal fluid positive) at diagnosis. Gross or near-total resection was achieved in 48 (89%) patients prior to RT. At a median follow-up of 4.4 years (range, 0.2-10.3 y), 4-year progression-free survival (PFS) was 75.1% ± 7.2%, and overall survival was 92.6% ± 4.4%. The molecular groups showed no significant difference in PFS (4-year estimates: posterior fossa ependymoma group A [PF-EPN-A; 42/54], 71.2% ± 8.3%; supratentorial ependymoma positive for v-rel avian reticuloendotheliosis viral oncogene homolog A [ST-EPN-RELA; 8/54], 83.3% ± 17.0%; and supratentorial ependymoma positive for Yes-associated protein [4/54], 100%, P = 0.22). Subtotal resection prior to RT was associated with an inferior PFS compared with gross or near-total resection (4-year PFS: 41.7% ± 22.5% vs 79.0% ± 7.1%, P = 0.024), as was PF-EPN-A group with 1q gain (P = 0.05). Histopathologic grading was not associated with outcomes (classic vs anaplastic; P = 0.89)., Conclusions: In this prospectively treated cohort of young children with ependymoma, ST-EPN-RELA tumors had a more favorable outcome than reported from retrospective data. Histologic grade did not impact outcome. PF-EPN-A with 1q gain and subtotal resection were associated with inferior outcomes., (© The Author(s) 2019. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

In Minnesota, medical cannabis was approved for use in 2014. From July 2015 to February 2019, our center certified 103 pediatric and young adult patients for the use of medical cannabis under the qualifying conditions of cancer and treatment-related symptoms. Here, we provide a review of the literature on medical cannabis use in pediatric and young adult cancer patients. We also provide demographic data on our patients certified for medical cannabis. The most common diagnoses were leukemia/lymphoma (36%), brain tumors (37%), and malignant solid tumors (26%). The most common indications were chemotherapy-related nausea, pain, and cancer cachexia. The age range at certification was 1.4-28.7 years (median 15.3 years). The time from cancer diagnosis to certification ranged from 0.5-197 months (median 8.9 months). The majority (94%) were certified during their first line of treatment. In the 32 patients who died from recurrent or progressive cancer, the time from certification to death was 1.3-30.3 months (median 4.4 years). Despite requesting certification, a subset (24%) never had medical cannabis dispensed. In our experience, pediatric and young adult oncology patients are interested in medical cannabis to help manage treatment-related symptoms. Ongoing analysis of this data will identify the therapeutic efficacy of medical cannabis.

Purpose: The Children's Oncology Group trial ACNS0121 estimated event-free survival (EFS) and overall survival for children with intracranial ependymoma treated with surgery, radiation therapy, and-selectively-with chemotherapy. Treatment was administered according to tumor location, histologic grade, and extent of resection. The impacts of histologic grade, focal copy number gain on chromosome 1q, and DNA methylation profiles were studied for those undergoing surgery and immediate postoperative conformal radiation therapy (CRT)., Methods: ACNS0121 included 356 newly diagnosed patients (ages 1 to 21 years). Patients with classic supratentorial ependymoma were observed after gross total resection (GTR). Those undergoing subtotal resection received chemotherapy, second surgery, and CRT. The remaining patients received immediate postoperative CRT after near-total resection or GTR. CRT was administered with a 1.0-cm clinical target volume margin. The cumulative total dose was 59.4 Gy, except for patients who underwent GTR and were younger than age 18 months (who received 54 Gy). Patients were enrolled between October 2003 and September 2007 and were observed for 5 years. Supratentorial tumors were evaluated for RELA fusion; infratentorial tumors, for chromosome 1q gain. Classification of posterior fossa groups A and B was made by methylation profiles., Results: The 5-year EFS rates were 61.4% (95% CI, 34.5% to 89.6%), 37.2% (95% CI, 24.8% to 49.6%), and 68.5% (95% CI, 62.8% to 74.2%) for observation, subtotal resection, and near-total resection/GTR groups given immediate postoperative CRT, respectively. The 5-year EFS rates differed significantly by tumor grade ( P = .0044) but not by age, location, RELA fusion status, or posterior fossa A/posterior fossa B grouping. EFS was higher for patients with infratentorial tumors without 1q gain than with 1q gain (82.8% [95% CI, 74.4% to 91.2%] v 47.4% [95% CI, 26.0% to 68.8%]; P = .0013)., Conclusion: The EFS for patients with ependymoma younger than 3 years of age who received immediate postoperative CRT and for older patients is similar. Irradiation should remain the mainstay of care for most subtypes.

Purpose: Children with brain tumors (BTs) experience fatigue and decreased quality of life (QOL). Physical activity (PA) is recommended during and after cancer treatment. We explored whether a fitness tracker intervention combined with tailored coaching by a physical therapist (PT) increased PA and QOL and decreased fatigue in children with BTs., Methods: Participants were 7 to 18 years' old, within 2 years of diagnosis, and received a 12-week PA intervention using a fitness tracker combined with 5 PT coaching sessions. Steps/day measured by Fitbit and self-reports of QOL, fatigue, and PA were evaluated at baseline, 12 weeks, and 24 weeks., Results: Participants had nonsignificant increase in steps/day. Total fatigue, general, and sleep/rest subscales improved while cognitive fatigue and QOL remained unchanged. Higher steps/day were associated with lower fatigue., Conclusion: This is a feasible intervention that may contribute to an increase in PA and improve fatigue in children with BTs.

Background: Medulloblastoma is associated with rare hereditary cancer predisposition syndromes; however, consensus medulloblastoma predisposition genes have not been defined and screening guidelines for genetic counselling and testing for paediatric patients are not available. We aimed to assess and define these genes to provide evidence for future screening guidelines., Methods: In this international, multicentre study, we analysed patients with medulloblastoma from retrospective cohorts (International Cancer Genome Consortium [ICGC] PedBrain, Medulloblastoma Advanced Genomics International Consortium [MAGIC], and the CEFALO series) and from prospective cohorts from four clinical studies (SJMB03, SJMB12, SJYC07, and I-HIT-MED). Whole-genome sequences and exome sequences from blood and tumour samples were analysed for rare damaging germline mutations in cancer predisposition genes. DNA methylation profiling was done to determine consensus molecular subgroups: WNT (MB WNT ), SHH (MB SHH ), group 3 (MB Group3 ), and group 4 (MB Group4 ). Medulloblastoma predisposition genes were predicted on the basis of rare variant burden tests against controls without a cancer diagnosis from the Exome Aggregation Consortium (ExAC). Previously defined somatic mutational signatures were used to further classify medulloblastoma genomes into two groups, a clock-like group (signatures 1 and 5) and a homologous recombination repair deficiency-like group (signatures 3 and 8), and chromothripsis was investigated using previously established criteria. Progression-free survival and overall survival were modelled for patients with a genetic predisposition to medulloblastoma., Findings: We included a total of 1022 patients with medulloblastoma from the retrospective cohorts (n=673) and the four prospective studies (n=349), from whom blood samples (n=1022) and tumour samples (n=800) were analysed for germline mutations in 110 cancer predisposition genes. In our rare variant burden analysis, we compared these against 53 105 sequenced controls from ExAC and identified APC, BRCA2, PALB2, PTCH1, SUFU, and TP53 as consensus medulloblastoma predisposition genes according to our rare variant burden analysis and estimated that germline mutations accounted for 6% of medulloblastoma diagnoses in the retrospective cohort. The prevalence of genetic predispositions differed between molecular subgroups in the retrospective cohort and was highest for patients in the MB SHH subgroup (20% in the retrospective cohort). These estimates were replicated in the prospective clinical cohort (germline mutations accounted for 5% of medulloblastoma diagnoses, with the highest prevalence [14%] in the MB SHH subgroup). Patients with germline APC mutations developed MB WNT and accounted for most (five [71%] of seven) cases of MB WNT that had no somatic CTNNB1 exon 3 mutations. Patients with germline mutations in SUFU and PTCH1 mostly developed infant MB SHH . Germline TP53 mutations presented only in childhood patients in the MB SHH subgroup and explained more than half (eight [57%] of 14) of all chromothripsis events in this subgroup. Germline mutations in PALB2 and BRCA2 were observed across the MB SHH , MB Group3 , and MB Group4 molecular subgroups and were associated with mutational signatures typical of homologous recombination repair deficiency. In patients with a genetic predisposition to medulloblastoma, 5-year progression-free survival was 52% (95% CI 40-69) and 5-year overall survival was 65% (95% CI 52-81); these survival estimates differed significantly across patients with germline mutations in different medulloblastoma predisposition genes., Interpretation: Genetic counselling and testing should be used as a standard-of-care procedure in patients with MB WNT and MB SHH because these patients have the highest prevalence of damaging germline mutations in known cancer predisposition genes. We propose criteria for routine genetic screening for patients with medulloblastoma based on clinical and molecular tumour characteristics., Funding: German Cancer Aid; German Federal Ministry of Education and Research; German Childhood Cancer Foundation (Deutsche Kinderkrebsstiftung); European Research Council; National Institutes of Health; Canadian Institutes for Health Research; German Cancer Research Center; St Jude Comprehensive Cancer Center; American Lebanese Syrian Associated Charities; Swiss National Science Foundation; European Molecular Biology Organization; Cancer Research UK; Hertie Foundation; Alexander and Margaret Stewart Trust; V Foundation for Cancer Research; Sontag Foundation; Musicians Against Childhood Cancer; BC Cancer Foundation; Swedish Council for Health, Working Life and Welfare; Swedish Research Council; Swedish Cancer Society; the Swedish Radiation Protection Authority; Danish Strategic Research Council; Swiss Federal Office of Public Health; Swiss Research Foundation on Mobile Communication; Masaryk University; Ministry of Health of the Czech Republic; Research Council of Norway; Genome Canada; Genome BC; Terry Fox Research Institute; Ontario Institute for Cancer Research; Pediatric Oncology Group of Ontario; The Family of Kathleen Lorette and the Clark H Smith Brain Tumour Centre; Montreal Children's Hospital Foundation; The Hospital for Sick Children: Sonia and Arthur Labatt Brain Tumour Research Centre, Chief of Research Fund, Cancer Genetics Program, Garron Family Cancer Centre, MDT's Garron Family Endowment; BC Childhood Cancer Parents Association; Cure Search Foundation; Pediatric Brain Tumor Foundation; Brainchild; and the Government of Ontario., (Copyright © 2018 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY-NC-ND 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

Because children diagnosed with WNT-activated medulloblastoma have a 10-year overall survival rate of 95%, active long-term follow-up is critically important in reducing mortality from other causes. Here, we describe an 11-year-old adopted female who developed multiple pilomatrixomas 3 years after diagnosis of WNT-activated medulloblastoma, an unusual finding that prompted deeper clinical investigation. A heterozygous germline APC gene mutation was discovered, consistent with familial adenomatous polyposis. Screening endoscopy revealed numerous precancerous polyps that were excised. This case highlights the importance of long-term follow-up of pediatric cancer survivors, including attention to unexpected symptoms, which might unveil an underlying cancer predisposition syndrome., (© 2017 Wiley Periodicals, Inc.)

The development of targeted anti-cancer therapies through the study of cancer genomes is intended to increase survival rates and decrease treatment-related toxicity. We treated a transposon-driven, functional genomic mouse model of medulloblastoma with 'humanized' in vivo therapy (microneurosurgical tumour resection followed by multi-fractionated, image-guided radiotherapy). Genetic events in recurrent murine medulloblastoma exhibit a very poor overlap with those in matched murine diagnostic samples (<5%). Whole-genome sequencing of 33 pairs of human diagnostic and post-therapy medulloblastomas demonstrated substantial genetic divergence of the dominant clone after therapy (<12% diagnostic events were retained at recurrence). In both mice and humans, the dominant clone at recurrence arose through clonal selection of a pre-existing minor clone present at diagnosis. Targeted therapy is unlikely to be effective in the absence of the target, therefore our results offer a simple, proximal, and remediable explanation for the failure of prior clinical trials of targeted therapy.

Diffuse intrinsic pontine glioma (DIPG) is a fatal brain cancer that arises in the brainstem of children, with no effective treatment and near 100% fatality. The failure of most therapies can be attributed to the delicate location of these tumors and to the selection of therapies on the basis of assumptions that DIPGs are molecularly similar to adult disease. Recent studies have unraveled the unique genetic makeup of this brain cancer, with nearly 80% found to harbor a p.Lys27Met histone H3.3 or p.Lys27Met histone H3.1 alteration. However, DIPGs are still thought of as one disease, with limited understanding of the genetic drivers of these tumors. To understand what drives DIPGs, we integrated whole-genome sequencing with methylation, expression and copy number profiling, discovering that DIPGs comprise three molecularly distinct subgroups (H3-K27M, silent and MYCN) and uncovering a new recurrent activating mutation affecting the activin receptor gene ACVR1 in 20% of DIPGs. Mutations in ACVR1 were constitutively activating, leading to SMAD phosphorylation and increased expression of the downstream activin signaling targets ID1 and ID2. Our results highlight distinct molecular subgroups and novel therapeutic targets for this incurable pediatric cancer.

Background: Preclinical models show that an antiangiogenic regimen at low-dose daily (metronomic) dosing may be effective against chemotherapy-resistant tumors. We undertook a prospective, open-label, single-arm, multi-institutional phase II study to evaluate the efficacy of a "5-drug" oral regimen in children with recurrent or progressive cancer., Procedure: Patients ≤21 years old with recurrent or progressive tumors were eligible. Treatment consisted of continuous oral celecoxib, thalidomide, and fenofibrate, with alternating 21-day cycles of low-dose cyclophosphamide and etoposide. Primary endpoint was to assess, within eight disease strata, activity of the 5-drug regimen over 27 weeks. Blood and urine angiogenesis markers were assessed., Results: One hundred one patients were enrolled; 97 began treatment. Median age was 10 years (range: 191 days-21 years); 47 (49%) were female. Disease strata included high-grade glioma (HGG, 21 patients), ependymoma (19), low-grade glioma (LGG, 12), bone tumors (12), medulloblastoma/primitive neuroectodermal tumor (PNET, 8), leukemia (4), neuroblastoma (3), and miscellaneous tumors (18). Treatment was generally well tolerated; most common toxicities were hematologic. Twenty-four (25%) patients completed 27 weeks therapy without progression, including HGG: 1 (5%), ependymoma: 7 (37%), LGG: 7 (58%), medulloblastoma/PNET: 1, neuroblastoma: 1, and miscellaneous tumors: 7 (39%). Best response was complete response (one patient with medulloblastoma), partial response (12), stable disease (36), progressive disease (47), and inevaluable (1). Baseline serum thrombospondin levels were significantly higher in patients successfully completing therapy than in those who progressed (P = 0.009)., Conclusion: The 5-drug regimen was well tolerated. Clinical activity was demonstrated in some but not all tumor strata., (© 2013 The Authors. Pediatric Blood & Cancer Published by Wiley Periodicals, Inc.)

In 3 patients with the Ewing family of tumors (EFT), morphoproteomic analyses of the tumors revealed constitutive activation of the mTOR, ERK, and NF-kappaB pathways, as evidenced by: (a) expression of phosphorylated (p)-mTOR, p-p70S6K, p-ERK 1/2, and p-NF-kappaB proteins using phosphospecific immunohistochemical probes directed against the activation sites; (b) nuclear translocation of p-p70S6K, p-ERK 1/2, and p-NF-kappaB p65; and (c) correlative expression of Ki-67 and Skp2 proteins consistent with cell cycling consequent to signal transduction by these pathways of convergence. This study examines the cytogenetic and molecular correlates and provides insight into therapeutic strategies relevant to this morphoproteomic profile. Based on a literature review, these observations appear to be the first morphoproteomic study of such pathways of convergence in tumors from EFT patients.

Human granulocyte-macrophage colony stimulating factor (GMCSF) and its high affinity receptor function to regulate the proliferation and differentiation of myeloid lineage hematopoietic cells, and may participate in the pathogenesis of many malignant myeloid diseases. We have used genetic engineering based on the elucidated molecular structures of human granulocyte-macrophage colony-stimulating factor and diphtheria toxin (DT) to produce a recombinant fusion toxin, DTctGMCSF, that targets diphtheria toxin to high affinity GMCSF receptors expressed on the surface of blast cells from a large fraction of patients with acute myeloid leukemia (AML). DTctGMCSF was specifically immunoreactive with antidiphtheria toxin and anti-GMCSF antiseras, and exhibited the characteristic catalytic activity of diphtheria toxin, catalyzing the in vitro ADP-ribosylation of purified elongation factor 2. The cytotoxic effects of DTctGMCSF were examined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-tetrazolium (MTT) bromide assay of cell viability and in vivo assays of protein synthesis inhibition. DTctGMCSF were specifically cytotoxic to human leukemia cell lines bearing high affinity receptors for human GMCSF with IC50 of 10(-9) to 10(-11) M. It was not toxic to mammalian hematopoietic cell lines lacking human GMCSF (hGMCSF) receptors. In receptor positive cells, cytotoxicity can be specifically blocked by a large excess of hGMCSF, confirming that its cytotoxicity is mediated through the hGMCSF receptor. THough DTctGMCSF inhibited granulocyte-macrophage colony formation by committed myeloid progenitor cells (CFU-GM), it did not significantly affect erythroid burst formation by committed erythroid progenitor cells (BFU-E), or mixed granulocyte-erythroid-macrophage-megakaryocyte colony formation by pluripotent multilineage progenitor cells (CFU-GEMM). DTctGMCSF holds promise for the treatment of myeloid lineage malignancies, and is a useful reagent to study hematopoiesis.

Contemporary therapies for acute myeloid leukemia (AML) commonly fail to cure patients because of the emergence of drug resistance. Drug resistance in AML is multifactorial but can be associated with the overexpression of transmembrane transporter molecules, including P-glycoprotein (Pgp) or the multidrug resistance-associated protein (MRP), or associated with inactivation of the p53 tumor suppressor gene, as well as overexpression of the anti-apoptotic protein bcl-2. We are investigating if novel recombinant biotherapeutics can circumvent these resistance mechanisms to effectively treat refractory AML. To target the lethal action of diphtheria toxin (DT) to high affinity granulocyte-macrophage colony-stimulating factor (GMCSF) receptors on AML blasts, we have produced a recombinant chimeric fusion toxin, DTctGMCSF. Since DTctGMCSF enters and kills its target cells by unique mechanisms (GMCSF-receptor binding and protein synthesis inhibition) and is not similar in structure to Pgp or MRP substrates, we postulated that it would be an active agent against therapy-resistant AML. DTctGMCSF was selectively cytotoxic (IC50 1-10ng/ml) to GMCSF-receptor positive AML cells expressing the Pgp- or MRP-associated multi-drug resistant phenotypes, despite high level resistance to conventional chemotherapeutic agents. DTctGMCSF also efficiently killed AML cells deficient in p53 expression, as well as radiation-resistant AML cells and mixed lineage leukemia cells expressing high levels of bcl-2. In addition, DTctGMCSF killed > 99% of primary leukemic progenitor cells from therapy-refractory AML patients under conditions that we have previously found to not adversely affect the proliferative capacity or differentiation of pluripotent normal hematopoietic progenitor cells. DTctGMCSF may prove useful in treating myeloid leukemias that are otherwise resistant to a wide range of conventional therapies.

Multiagent chemotherapy regimens fail to cure more than one-half of the patients with acute myeloid leukemia (AML) because of the emergence of dominant multidrug-resistant subclones of leukemia cells. We have developed a recombinant diphtheria toxin-human granulocyte macrophage colony-stimulating factor chimeric fusion protein (DTctGMCSF) that specifically targets GMCSF receptor-positive AML cells. This novel biotherapeutic agent induced rapid apoptotic cell death of chemotherapy-resistant AML cell lines and primary leukemic cells from treatment-refractory AML patients. Our results suggest that DTctGMCSF may be useful in the treatment of AML patients whose leukemia has recurred and developed resistance to contemporary chemotherapy programs.