A common polymorphism in the 5' UTR of ERCC5 creates an upstream ORF that confers resistance to platinum-based chemotherapy.

We show that a common polymorphic variant in the ERCC5 5' untranslated region (UTR) generates an upstream ORF (uORF) that affects both the background expression of this protein and its ability to be synthesized following exposure to agents that cause bulky adduct DNA damage. Individuals that harbor uORF1 have a marked resistance to platinum-based agents, illustrated by the significantly reduced progression-free survival of pediatric ependymoma patients treated with such compounds. Importantly, inhibition of DNA-PKcs restores sensitivity to platinum-based compounds by preventing uORF1-dependent ERCC5 expression. Our data support a model in which a heritable 5' noncoding mRNA element influences individuals' responses to platinum-based chemotherapy.

The role of artificial intelligence in paediatric neuroradiology.

Imaging plays a fundamental role in the managing childhood neurologic, neurosurgical and neuro-oncological disease. Employing multi-parametric MRI techniques, such as spectroscopy and diffusion- and perfusion-weighted imaging, to the radiophenotyping of neuroradiologic conditions is becoming increasingly prevalent, particularly with radiogenomic analyses correlating imaging characteristics with molecular biomarkers of disease. However, integration into routine clinical practice remains elusive. With modern multi-parametric MRI now providing additional data beyond anatomy, informing on histology, biology and physiology, such metric-rich information can present as information overload to the treating radiologist and, as such, information relevant to an individual case can become lost. Artificial intelligence techniques are capable of modelling the vast radiologic, biological and clinical datasets that accompany childhood neurologic disease, such that this information can become incorporated in upfront prognostic modelling systems, with artificial intelligence techniques providing a plausible approach to this solution. This review examines machine learning approaches than can be used to underpin such artificial intelligence applications, with exemplars for each machine learning approach from the world literature. Then, within the specific use case of paediatric neuro-oncology, we examine the potential future contribution for such artificial intelligence machine learning techniques to offer solutions for patient care in the form of decision support systems, potentially enabling personalised medicine within this domain of paediatric radiologic practice.

Outcomes with respect to extent of surgical resection for pediatric atypical teratoid rhabdoid tumors.

PURPOSE: To evaluate overall survival for atypical teratoid rhabdoid tumors (ATRTs) in relation to extent of surgical resection. METHODS: The neurosurgical tumor databases from three UK Pediatric centers (University Hospital of Wales, Alder Hey and Royal Manchester Children's Hospital) were analyzed. Patients with a diagnosis of ATRT were identified between 2000 and 2018. Data was collected regarding demographics, extent of resection, complications, and overall survival. RESULTS: Twenty-four patients diagnosed with ATRT underwent thirty-eight operations. The age range was 20 days to 147 months (median 17.5 months). The most common location for the tumor was the posterior fossa (nine patients; 38%). Six patients (25%) underwent a complete total resection (CTR), seven (29%) underwent a near total resection (NTR), eight (33.3%) underwent a subtotal resection (STR), and three patients (12.5%) had biopsy only. Two-thirds of patients who underwent a CTR are still alive, as of March 2019, compared to 29% in the NTR and 12.5% in the STR groups. Out of the thirty-eight operations, there were a total of twenty-two complications, of which the most common was pseudomeningocele (27%). The extent of surgical resection (p = 0.021), age at surgery (p = 0.00015), and the presence of metastases at diagnosis (0.015) significantly affected overall survival. CONCLUSIONS: Although these patients are a highly vulnerable group, maximal resection is recommended where possible, for the best chance of long-term survival. However, near total resections are likely beneficial when compared with subtotal resections and biopsy alone. Maximal surgical resection should be combined with adjuvant therapies for the best long-term outcomes.

Papillary craniopharyngioma in a 4-year-old girl with BRAF V600E mutation: a case report and review of the literature.

INTRODUCTION: Craniopharyngiomas are one of the most frequently diagnosed hypothalamo-pituitary tumors in childhood. The adamantinomatous histological subtype accounts for most pediatric cases, while the papillary variant is almost exclusively diagnosed in adults. Here, we report a case of papillary craniopharyngioma in a very young child, confirmed by molecular tissue analysis. CASE REPORT: A 4-year-old girl was being investigated for symptomatic central hypothyroidism. Brain MR imaging revealed a large solid/cystic suprasellar mass, splaying the optic chiasm and measuring 3 × 1.9 × 2.3 cm. The patient underwent a transsphenoidal near total resection of the lesion, which was encased within a tumor capsule. Post-operatively, the patient developed transient diabetes insipidus but otherwise recovered well. The pathology of the lesion was consistent with a papillary craniopharyngioma with regions of stratified squamous epithelium accompanied by superficial goblet cells and ciliated cells. Subsequent next-generation sequencing analysis of the lesion confirmed the presence of a BRAF V600E mutation (BRAFc.1799T>A p. (Val600Glu). To date, she remains free from progression 1 year following surgery. CONCLUSION: This is the youngest case published to date of papillary craniopharyngioma with a confirmed BRAF V600E mutation. The case encourages discussion about the most appropriate adjuvant therapy for tumor progression in such cases, given the risks of radiotherapy to the developing brain and the increasing availability of oral BRAF inhibitor therapy.

Ventricular metastatic dissemination of a paediatric craniopharyngioma: case report and literature review.

Distant intraventricular metastasis is extremely rare in childhood craniopharyngioma. Here, we report the isolated posterior ventricular recurrence of an adamantinomatous craniopharyngioma, in a child previously treated with surgery and proton beam therapy for local progression. The importance of surveillance imaging is highlighted, while specific surgical approaches and techniques are considered.

Outcomes of children with central nervous system germinoma treated with multi-agent chemotherapy followed by reduced radiation.

CNS germinomas have an excellent prognosis with radiation therapy alone. However, in children, volume and dose of CNS radiation are associated with neurocognitive and neuroendocrine sequelae. Our objective was to determine long-term outcomes of our cohort who received chemotherapy and reduced radiation. This retrospective cohort study analyzed treatment and outcome of intracranial germinoma patients consecutively treated at Sick Kids, Toronto, Canada, from January 2000 to December 2013. 24 children (13 male, 11 female; median age 13.36 years) were identified. Median follow up was 61 months (range 1-144 months). Tumor location was suprasellar (n = 9), bifocal (8), pineal (6), and basal ganglia (1). Three children showed dissemination on imaging. 2/24 had only elevated serum human chorionic gonadotropin, 3/24 only elevated lumbar cerebrospinal fluid (CSF) hCG, and 2/24 had both elevated serum and lumbar CSF hCG. 23/24 children completed treatment and received multi-agent chemotherapy followed by either ventricular radiation (2340-2400 cGy) (n = 9), ventricular radiation + boost (1600 cGy) (n = 8), whole brain (2340 cGy) (n = 3), focal (4000 cGy) (n = 2) or craniospinal radiation (2340 cGy) (n = 1). Five-year progression free and overall survival was 96 and 100 % respectively. 8/24 patients with ventricular radiation ± boost (2340/4000 cGy) displayed stable full scale intelligence quotient over a mean interval of 3 years following radiation, but showed declined processing speed. In this limited experience, excellent 5-year overall survival rates were achieved with chemotherapy followed by reduced whole ventricular radiation even if ventricular radiation was delivered without boost.

Multiple synchronous sites of origin of vestibular schwannomas in neurofibromatosis Type 2.

BACKGROUND: Neurofibromatosis Type 2 (NF2) is a dominantly inherited tumour syndrome with a phenotype which includes bilateral vestibular (eighth cranial nerve) schwannomas. Conventional thinking suggests that these tumours originate at a single point along the superior division of the eighth nerve. METHODS: High resolution MRI was performed in children genetically proven to have NF2. The superior vestibular nerve (SVN) and inferior vestibular nerve (IVN) were visualised along their course with points of tumour origin calculated as a percentage relative to the length of the nerve. RESULTS: Out of 41 patients assessed, 7 patients had no identifiable eighth cranial nerve disease. In 16 patients there was complete filling of the internal auditory meatus by a tumour mass such that its specific neural origin could not be determined. In the remaining 18 cases, 86 discrete separate foci of tumour origin on the SVN or IVN could be identified including 23 tumours on the right SVN, 26 tumours on the right IVN, 18 tumours on the left SVN and 19 tumours on the left IVN. DISCUSSION: This study, examining the origins of vestibular schwannomas in NF2, refutes their origin as being from a single site on the transition zone of the superior division of the vestibular nerve. We hypothesise a relationship between the number of tumour foci, tumour biology and aggressiveness of disease. The development of targeted drug therapies in addition to bevacizumab are therefore essential to improve prognosis and quality of life in patients with NF2 given the shortcomings of surgery and radiation treatments when dealing with the multifocality of the disease.

Diabetes insipidus in pediatric germinomas of the suprasellar region: characteristic features and significance of the pituitary bright spot.

The pituitary bright spot is acknowledged to indicate functional integrity of the posterior pituitary gland, whilst its absence supports a diagnosis of central diabetes insipidus (DI). This feature was evaluated, together with the incidence and clinical characteristics of DI in children with suprasellar/neurohypophyseal germinomas. We performed a review of all suprasellar (SS) or bifocal (BF) germinoma pediatric patients treated in Toronto since 2000. Demographics, symptomatology, treatment outcome and imaging were evaluated. Nineteen patients fulfilled inclusion criteria (10 SS, 9 BF; median age 12.5 years (6.2-16.8 years)). All remained alive at 6.4 years median follow-up (1.2-13.7 years) after receiving chemotherapy and radiotherapy (13 focal/ventricular, four whole brain, two neuraxis), with only one progression. All had symptoms of DI at presentation with a symptom interval above one year in eight cases (42 %). Desmopressin was commenced and maintained in 16 patients (84 %). The pituitary bright spot was lost in most diagnostic interpretable cases, but was appreciated in three patients (18 %) who had normal serum sodium values compared to 'absent' cases (p = 0.013). For two such cases, spots remained visible until last follow-up (range 0.4-3.3 years), with one still receiving desmopressin. No case of bright spot recovery was observed following therapy. Protracted symptom intervals for germinoma-induced central DI may reflect poor clinical awareness. Explanations for persistence of the pituitary bright spot in symptomatic patients remain elusive. Desmopressin seldom reverses the clinical features of germinoma-induced DI to allow discontinuation, nor does treatment cause bright spot recovery.

Germline SMARCE1 mutations predispose to both spinal and cranial clear cell meningiomas.

We recently reported SMARCE1 mutations as a cause of spinal clear cell meningiomas. Here, we have identified five further cases with non-NF2 spinal meningiomas and six with non-NF2 cranial meningiomas. Three of the spinal cases and three of the cranial cases were clear cell tumours. We screened them for SMARCE1 mutations and investigated copy number changes in all point mutation-negative samples. We identified two novel mutations in individuals with spinal clear cell meningiomas and three mutations in individuals with cranial clear cell meningiomas. Copy number analysis identified a large deletion of the 5' end of SMARCE1 in two unrelated probands with spinal clear cell meningiomas. Testing of affected and unaffected relatives of one of these individuals identified the same deletion in two affected female siblings and their unaffected father, providing further evidence of incomplete penetrance of meningioma disease in males. In addition, we found loss of SMARCE1 protein in three of 10 paraffin-embedded cranial clear cell meningiomas. Together, these results demonstrate that loss of SMARCE1 is relevant to cranial as well as spinal meningiomas. Our study broadens the spectrum of mutations in the SMARCE1 gene and expands the phenotype to include cranial clear cell meningiomas.

Tumor volumetric measurements in surgically inaccessible pediatric low-grade glioma.

Tumor measurement is important in unresectable pediatric low-grade gliomas (pLGGs) to determine either the need for treatment or assess response. Standard methods measure the product of the largest 2 lengths from transverse, anterior-posterior, and cranio-caudal dimensions (SM, cm). This single-institution study evaluated tumor volume measurements (VM, cm) in such pLGGs. Of 50 patients treated with chemotherapy for surgically inaccessible pLGG, 8 met the inclusion criteria of having 2 or more sequential MRI studies of T1-weighted Fast-Spoiled Gradient Recalled acquisition. SM and VM were performed by 2 independent neuroradiologists. Associations of measurement methods with defined therapeutic response criteria and patient clinical status were assessed. The mean tumor size at the first MRI scan was 20 cm and 398 cm according to SM and VM, respectively. VM results did not differ significantly from SM-derived spherical volume calculations (Pearson correlation, P<0.0001) with a high interrater reliability. Both methods were concordant in defining the tumor response according to the current criteria, although radiologic progressive disease was not associated with clinical status (SM: P=0.491, VM: P=0.208). In this limited experience, volumetric analysis of unresectable pLGGs did not seem superior to the standard linear measurements for defining tumor response.