Diagnostic and Dosimetry Features of [64Cu]CuCl2 in High-Grade Paediatric Infiltrative Gliomas.

PURPOSE OF THE REPORT: Paediatric diffuse high-grade gliomas (PDHGG) are rare central nervous system neoplasms lacking effective therapeutic options. Molecular imaging of tumour metabolism might identify novel diagnostic/therapeutic targets. In this study, we evaluated the distribution and the dosimetry aspects of [64Cu]CuCl2 in PDHGG subjects, as copper is a key element in cellular metabolism whose turnover may be increased in tumour cells. MATERIAL AND METHODS: Paediatric patients with PDHGG were prospectively recruited. [64Cu]CuCl2 PET/CT was performed 1 h after tracer injection; if the scan was positive, it was repeated 24 and 72 h later. Lesion standardised uptake value (SUV) and target-to-background ratio (TBR) were calculated. Tumour and organ dosimetry were computed using the MIRD algorithm. Each patient underwent an MRI scan, including FLAIR, T2-weighted and post-contrast T1-weighted imaging. RESULTS: Ten patients were enrolled (median age 9, range 6-16 years, 6 females). Diagnoses were diffuse midline gliomas (n = 8, 5 of which with H3K27 alterations) and diffuse hemispheric gliomas (n = 2). Six patients had visible tracer uptake (SUV: 1.0 ± 0.6 TBR: 5 ± 3.1). [64Cu]CuCl2 accumulation was always concordant with MRI contrast enhancement and was higher in the presence of radiological signs of necrosis. SUV and TBR progressively increased on the 24- and 72-h acquisitions (p < 0.05 and p < 0.01, respectively). The liver and the abdominal organs received the highest non-target dose. CONCLUSIONS: [64Cu]CuCl2 is a well-tolerated radiotracer with reasonably favourable dosimetric properties, showing selective uptake in tumour areas with visible contrast enhancement and necrosis, thus suggesting that blood-brain barrier damage is a pre-requisite for its distribution to the intracranial structures. Moreover, tracer uptake showed an accumulating trend over time. These characteristics could deserve further analysis, to determine whether this radiopharmaceutical might have a possible therapeutic role as well.

Early molecular diagnosis of BRAF status drives the neurosurgical management in BRAF V600E-mutant pediatric low-grade gliomas: a case report.

BACKGROUND: To date, this is the only report showing with close and consecutive magnetic resonance images the extremely rapid response of two types of pediatric low-grade gliomas (PLGG) to vemurafenib and its impact on the surgical approach. CASES PRESENTATION: We report two cases of symptomatic PLGG treated with vemurafenib, a BRAF inhibitor: in a 12-year-old girl it was used as first-line medical treatment, reducing the tumor by 45% within a month and stabilizing to 76% after a year; in a 3-year-old boy with no improvement after SIOP LGG 2004 Protocol, vemurafenib induced in only one week a 34% shrinkage and solved the hydrocephalus, avoiding surgical operation. DISCUSSION AND CONCLUSIONS: Our cases demonstrate how an early molecular diagnosis of BRAF mutations through the neurosurgical biopsy is essential to promptly start targeted therapies., whose effect can influence both therapeutic and surgical decisions, hopefully reducing the occurrence of second neurosurgery with associated risks of neurological sequelae.

Sleep Disturbances in Pediatric Craniopharyngioma: A Systematic Review.

Craniopharyngiomas are rare brain tumors of the sellar region and are the most common non-neuroepithelial intracerebral neoplasm in children. Despite a low-grade histologic classification, craniopharyngiomas can have a severe clinical course due to hypothalamic involvement. The hypothalamus plays a crucial role in regulating vital functions, and it is a critical component of the sleep-wake regulatory system. This systematic review aims to provide an overview of the current knowledge on sleep disorders in patients with craniopharyngioma to unravel their underlying mechanisms and identify possible therapeutic strategies. A comprehensive electronic literature search of the PubMed/MEDLINE and Scopus databases was conducted in accordance with the PRISMA® statement. Extensively published, peer-reviewed articles involving patients with childhood craniopharyngioma and focused on this specific topic were considered eligible for inclusion. Thirty-two articles were included; a high prevalence of excessive daytime sleepiness was reported in CP patients, with wide variability (25-100%) depending on the diagnostic method of detection (25-43% by subjective measures, 50-100% by objective investigations). In particular, secondary narcolepsy was reported in 14-35%, sleep-disordered breathing in 4-46%. Moreover, sleep-wake rhythm dysregulation has been notified, although no prevalence data are available. Possible mechanisms underlying these disorders are discussed, including hypothalamic injury, damage to the suprachiasmatic nucleus, low melatonin levels, hypocretin deficiency, and hypothalamic obesity. The diagnosis and management of sleep disorders and associated comorbidities are challenging. This review summarizes the pathophysiology of sleep disorders in childhood-onset CP and the main treatment options. Finally, a possible diagnostic algorithm in order to accurately identify and treat sleep disorders in these patients is proposed.

Dyslipidemia in Children Treated with a BRAF Inhibitor for Low-Grade Gliomas: A New Side Effect?

BRAF inhibitors, in recent years, have played a central role in the disease control of unresectable BRAF-mutated pediatric low-grade gliomas (LGGs). The aim of the study was to investigate the acute and long-term effects of vemurafenib on the lipid metabolism in children treated for an LGG. In our cohort, children treated with vemurafenib (n = 6) exhibited alterations in lipid metabolism a few weeks after starting, as was demonstrated after 1 month (n = 4) by the high plasma levels of the total cholesterol (TC = 221.5 ± 42.1 mg/dL), triglycerides (TG = 107.8 ± 44.4 mg/dL), and low-density lipoprotein (LDL = 139.5 ± 51.5 mg/dL). Despite dietary recommendations, the dyslipidemia persisted over time. The mean lipid levels of the TC (222.3 ± 34.7 mg/dL), TG (134.8 ± 83.6 mg/dL), and LDL (139.8 ± 46.9 mg/dL) were confirmed abnormal at the last follow-up (45 ± 27 months, n = 6). Vemurafenib could be associated with an increased risk of dyslipidemia. An accurate screening strategy in new clinical trials, and a multidisciplinary team, are required for the optimal management of unexpected adverse events, including dyslipidemia.

Calcifications in diffuse leptomeningeal glioneuronal tumors: a case series.

Diffuse leptomeningeal glioneuronal tumor (DLGNT) is a new rare entity, typically seen in the pediatric population. Classical neuroimaging features at clinical onset include marked subarachnoid/leptomeningeal enhancement and tiny pseudo-cystic lesions along the subpial surface of the neuroaxis, frequently associated with communicating hydrocephalus. However, data on the long-term appearance of this tumor on computed tomography (CT) and magnetic resonance imaging (MRI) are still lacking. We describe a peculiar pattern of progressive leptomeningeal calcifications in three young patients with DLGNT. The calcifications, mainly located in the basal cisterns, sylvian fissures and posterior surface of the thalami, were present at clinical onset in the older subject and appeared about 2 years after clinical onset in the other two. Patients underwent different schemes of chemotherapy, variably associated with craniospinal irradiation and/or bevacizumab. In all cases, calcifications were present before starting craniospinal irradiation and/or treatment with bevacizumab. This novel peculiar pattern of progressive leptomeningeal calcifications expands the imaging phenotype of DLGNT and should be carefully sought, especially in later phases of the disease. Taking into consideration the onset, evolution, and absence of direct relationship with treatments, we hypothesize that calcifications in DLGNTs might be the effect of natural changes in the tumor and its environment.

Role of Dynamic Parameters of 18F-DOPA PET/CT in Pediatric Gliomas.

PURPOSE OF THE REPORT: PET with 18F-DOPA can be used to evaluate grading and aggressiveness of pediatric cerebral gliomas. However, standard uptake parameters may underperform in circumscribed lesions and in diffuse pontine gliomas. In this study, we tested whether dynamic 18F-DOPA PET could overcome these limitations. PATIENTS AND METHODS: Patients with available dynamic 18F-DOPA PET were included retrospectively. Static parameters (tumor/striatum ratio [T/S] and tumor/cortex ratio [T/N]) and dynamic ones, calculated on the tumor time activity curve (TAC), including time-to-peak (TTP), slope steepness, the ratio between tumor and striatum TAC steepness (dynamic slope ratio [DSR]), and TAC shape (accumulation vs plateau), were evaluated as predictors of high/low grading (HG and LG) and of progression-free survival and overall survival. RESULTS: Fifteen patients were included; T/S, T/N, TTP, TAC slope steepness, and DSR were not significantly different between HG and LG. The accumulation TAC shape was more prevalent in the LG than in the HG group (75% vs 27%). On progression-free survival univariate analysis, TAC accumulation shape predicted longer survival (P < 0.001), whereas T/N and DSR showed borderline significance; on multivariate analyses, only TAC shape was retained (P < 0.01, Harrell C index, 0.93-0.95). On overall survival univariate analysis, T/N (P < 0.05), DSR (P < 0.05), and TAC "accumulating" shape predicted survival (P < 0.001); once more, only this last parameter was retained in the multivariate models (P < 0.05, Harrell C index, 0.86-0.89). CONCLUSIONS: Dynamic 18F-DOPA PET analysis outperforms the static parameter evaluation in grading assessment and survival prediction. Evaluation of the curve shape is a simple-to-use parameter with strong predictive power.

Atypical teratoid/rhabdoid tumor in adults: a systematic review of the literature with meta-analysis and additional reports of 4 cases.

INTRODUCTION: Atypical teratoid/rhabdoid tumor (AT/RT) is a highly aggressive embryonal CNS neoplasm, characterized by inactivation of SMARCB1 (INI1) or rarely of SMARCA4 (BRG1). While it is predominantly a childhood tumor, AT/RT is rare in adults. METHODS: We provide a comprehensive systematic review of literature with meta-analysis; 92 adult cases were found from 74 articles. We additionally present 4 cases of adult AT/RTs (age ranging from 19 to 29 years), located to cerebellum in 2 cases, to ponto-cerebellar angle in 1 case and to spinal cord in the remaining case. RESULTS: Microscopic features of our 4 cases showed a highly cellular tumor with rhabdoid morphology and high mitotic activity. All tumor cells lacked nuclear SMARCB1/INI1 protein expression. In case no. 3 we also performed methylation profiling which clustered the tumor with pediatric AT/RT-MYC subgroup. Prognosis remains poor in both pediatric and adult population with a median overall survival of 11 months. Our review demonstrated median overall survival of 15 months among the adult populations. However, consistent with a recent review, adult AT/RT seems to have highly variable prognosis and some patients reach long term survival with 22.9% of 5-year survival without evidence of disease and mean follow up time of 35.9 months (SD = 36.5). 27.1% of dissemination was also reported among the adult population. CONCLUSIONS: Adult AT/RTs predominantly arise in female patients and in supratentorial location. Midline structures, including the sellar region, are the most affected sites, especially among females aged > 40 years. Male gender is more prevalent between the age of 18 and 40 years and more frequently associated with non-midline tumors. Factors significantly associated with better prognosis are patient's age (< 40 years), combined radio-chemotherapy adjuvant approach and Ki-67 score < 40%.

Case Report: The Emerging Role of Ring Chromosome 22 in Phelan-McDermid Syndrome With Atypical Teratoid/Rhabdoid Tumor: The First Child Treated With Growth Hormone.

Atypical teratoid/rhabdoid tumors (AT/RTs) in the rhabdoid tumor predisposition syndromes are most often caused by germline mutations of the SMARCB1 gene located in chromosome 22q11.2. Although rarely, it can also result from the constitutional ring chromosome 22 (r22): during mitosis the ring chromosome may lead to an increased rate of somatic mutations, resulting in rhabdoid tumor predispositions when the tumor-suppressor gene SMARCB1 is involved. Individuals with r22 may present similar features as those with Phelan-McDermid syndrome (PMDS) due to 22q13.3 deletion, including the SHANK3 gene. Despite several reports on AT/RT in children with r22 and/or PMDS have been published, the role of constitutional r22 as new oncogenic mechanism for AT/RT is still under investigation. There is not a lot of data available on therapeutic and prognostic implications of r22 in AT/RT and PMDS. Herein, we present the first case of a child with constitutional r22, PMDS and AT/RT of the brain, who is a long term survivor and is been treated with growth hormone. We also describe an unexpected adverse reaction to midazolam.

Sleep disturbances in craniopharyngioma: a challenging diagnosis.

Craniopharyngiomas are rare solid or mixed solid and cystic tumors that arise from Rathke's pouch remnants along the pituitary-hypothalamic axis, from the sella turcica to the brain third ventricle. Both the tumor and its treatment can lead to significant neurological and endocrinological complications. Due to the essential role of the hypothalamus in the complex neurophysiologic process of sleep, tumors involving the hypothalamic area may be responsible for disturbances in sleep-wake regulation with alterations in the circadian rhythm, sleep fragmentation, and increased daytime sleepiness. We report two cases of patients with craniopharyngioma, who came to our attention due to the occurrence of episodes characterized by psychomotor slowing and afinalistic limb movements, temporal and spatial disorientation, psychomotor agitation, and oneiric stupor like episodes. A comprehensive clinical data collection and a targeted diagnostic work-up led to a diagnosis of severe sleep disorder characterized by hypersomnia, altered sleep-wake rhythm, and sleep-related breathing disorder. In addition, the polysomnography revealed peculiar alterations in the sleep structure. The diagnostic work-up lead to an accurate differential diagnosis between epileptic seizures and episodes expressions of sleep disturbances. These clinical features can be challenging to diagnose and can lead to misdiagnosis and inappropriate treatment. Diagnosis of sleep disorders is crucial, considering the impact of sleep on general health, cognition, and neuropsychological functioning. These findings support the need to incorporate a comprehensive sleep evaluation in childhood brain tumor involving the suprasellar/hypothalamic region.

Genotype-Phenotype Correlations in Neurofibromatosis Type 1: A Single-Center Cohort Study.

Neurofibromatosis type 1 (NF1) is a proteiform genetic condition caused by pathogenic variants in NF1 and characterized by a heterogeneous phenotypic presentation. Relevant genotype-phenotype correlations have recently emerged, but only few pertinent studies are available. We retrospectively reviewed clinical, instrumental, and genetic data from a cohort of 583 individuals meeting at least 1 diagnostic National Institutes of Health (NIH) criterion for NF1. Of these, 365 subjects fulfilled ≥2 NIH criteria, including 235 pediatric patients. Genetic testing was performed through cDNA-based sequencing, Next Generation Sequencing (NGS), and Multiplex Ligation-dependent Probe Amplification (MLPA). Uni- and multivariate statistical analysis was used to investigate genotype-phenotype correlations. Among patients fulfilling ≥ 2 NIH criteria, causative single nucleotide variants (SNVs) and copy number variations (CNVs) were detected in 267/365 (73.2%) and 20/365 (5.5%) cases. Missense variants negatively correlated with neurofibromas (p = 0.005). Skeletal abnormalities were associated with whole gene deletions (p = 0.05) and frameshift variants (p = 0.006). The c.3721C>T; p.(R1241*) variant positively correlated with structural brain alterations (p = 0.031), whereas Lisch nodules (p = 0.05) and endocrinological disorders (p = 0.043) were associated with the c.6855C>A; p.(Y2285*) variant. We identified novel NF1 genotype-phenotype correlations and provided an overview of known associations, supporting their potential relevance in the implementation of patient management.

Endothelial Dysfunction in Childhood Cancer Survivors: A Narrative Review.

Assessment of endothelial dysfunction in cancer survivors may have a role in the early identification of non-communicable diseases and cardiovascular late effects. Oncological therapies may impair endothelial function. Therefore, in patients such as childhood cancer survivors who could benefit from early cardioprotective pharmacological interventions, it is essential to monitor endothelial function, even if the optimal methodology for investigating the multifaceted aspects of endothelial dysfunction is still under debate. Biochemical markers, as well as invasive and non-invasive tools with and without pharmacological stimuli have been studied. Human clinical studies that have examined lifestyle or cancer treatment protocols have yielded evidence showing the involvement of lipid and lipoprotein levels, glycemic control, blood pressure, adiposity, inflammation, and oxidative stress markers on the state of endothelial health and its role as an early indicator of cardiometabolic risk. However, with regards to pharmacological interventions, cautious interpretation of the result attained whilst monitoring the endothelial function is warranted due to methodological limitations and substantial heterogeneity of the results reported in the published studies. In this narrative review, an overview of evidence from human clinical trials examining the effects of cancer therapies on endothelial disease is provided together with a discussion of endothelial function assessment using the different non-invasive techniques available for researchers and clinicians, in recent years.

Correlation of multimodal 18F-DOPA PET and conventional MRI with treatment response and survival in children with diffuse intrinsic pontine gliomas.

To evaluate the contribution of 18F-dihydroxyphenylalanine (DOPA) PET in association with conventional MRI in predicting treatment response and survival outcome of pediatric patients with diffuse intrinsic pontine gliomas (DIPGs). Methods: We retrospectively analyzed 19 children with newly diagnosed DIPGs who underwent 18F-DOPA PET/CT and conventional MRI within one week of each other at admission and subsequent MRI follow-up. Following co-registration and fusion of PET and MRI, 18F-DOPA uptake avidity and extent (PET tumor volume and uniformity) at admission, along with MRI indices including presence of ring contrast-enhancement, tumor volume at admission and at maximum response following first-line treatment, were evaluated and correlated with overall survival (OS). The association between 18F-DOPA uptake tumor volume at admission and MRI tumor volume following treatment was evaluated. Statistics included Wilcoxon signed-rank and Mann-Whitney U tests, Kaplan-Meier OS curve and Cox analysis. Results: DIPGs with a 18F-DOPA uptake Tumor/Striatum (T/S) ratio >1 presented an OS ≤ 12 months and lower degree of tumor volume reduction following treatment (p = 0.001). On multivariate analysis, T/S (p = 0.001), ring enhancement (p = 0.01) and the degree of MRI tumor volume reduction (p = 0.01) independently correlated with OS. In all patients, areas of increased 18F-DOPA uptake overlapped with regions demonstrating more prominent residual components/lack of response following treatment. Conclusions:18F-DOPA PET provides useful information for evaluating the metabolism of DIPGs. T/S ratio is an independent predictor of outcome. 18F-DOPA uptake extent delineates tumoral regions with a more aggressive biological behaviour, less sensitive to first line treatment.

Pediatric Diffuse Midline Gliomas H3 K27M-Mutant and Non-Histone Mutant Midline High-Grade Gliomas in Neurofibromatosis Type 1 in Comparison With Non-Syndromic Children: A Single-Center Pilot Study.

Background: Pediatric neurofibromatosis type 1 (NF1) patients rarely develop aggressive central nervous system tumors. Among high-grade gliomas (HGGs), histone mutant diffuse midline gliomas (DMGs H3 K27M-mutant) have exceptionally been reported. The aim of this retrospectives single-center study was to compare the clinical behavior of DMGs H3 K27M-mutant and non-histone mutant midline HGGs in NF1 vs. non-syndromic children and to report imaging features of NF1 HGGs. Method: We conducted a retrospective review of cerebral DMGs H3 K27M-mutant or non-histone mutant HGGs in 18 patients with or without NF1 followed at our institution between 2010 and 2018. Differences in outcomes, notably progression-free survival (PFS) and overall survival (OS), were evaluated. Results: Two patients were identified with genetically confirmed diagnosis of NF1 and cerebral HGGs (one DMG H3 K27M-mutant and one histone wild type). Both subjects presented with midline mass lesions with imaging features of aggressive biological activity on advanced MRI or amino-acid PET. During the same time period, 16 non-NF1 patients (11 subjects with DMGs H3 K27M-mutant and 5 with non-histone mutant midline HGGs) were treated at our institution. The two patients with NF1 and HGGs presented a PFS of 3 months and an OS of 5 and 7 months. Median PFS and OS of children without NF1 were respectively 6 and 10 months in DMGs H3 K27M-mutant, and 6 and 11 months in H3 K27M wild-type tumors. Seventy-five percent of subjects with non-NF1 HGGs presented a PFS >4 months compared to 0% in NF1 patients. The 8-month OS of patients with non-NF1 HGGs was 81% compared to 0% in NF1 patients. Conclusions: Cerebral HGGs arising in midline structures rarely occur in pediatric patients with NF1 and present with extremely poor prognosis, worse than HGGs developing in non-NF1 patients, independent of the presence or absence of H3 K27M mutation. Imaging features of aggressive biological activity on advanced MRI or amino-acid PET imaging suggest prompt neuropathological and molecular investigations.

Role of diffusion weighted imaging for differentiating cerebral pilocytic astrocytoma and ganglioglioma BRAF V600E-mutant from wild type.

PURPOSE: BRAF V600E mutation is a distinctive genomic alteration of pediatric low-grade gliomas with prognostic and therapeutic implications. The aim of this retrospective multicenter study was to analyze imaging features of BRAF V600E-mutant and wild-type cerebral pilocytic astrocytomas (PAs) and gangliogliomas (GGs), focusing on the role of diffusion weighted imaging (DWI). METHODS: We retrospectively evaluated 56 pediatric patients with histologically proven, treatment-naïve PAs and GGs who underwent conventional MRI, DWI, and molecular analysis for BRAF V600E mutation. Twenty-three subjects presented BRAF V600E-mutant (12 PAs and 11 GGs) and 33 BRAF V600E wild-type (26 PAs and 7 GGs) tumors. Imaging studies were reviewed for dominant site, margin definition, hemorrhage, calcification, cystic components, contrast enhancement, and relative mean and minimum ADC values (rADCmean and rADCmin). Statistics included Fisher's exact test, Student t test, general linear model, and receiver operating characteristic (ROC) analysis. RESULTS: PA and GG BRAF V600E-mutant had significantly lower rADCmean (p < 0.001) and rADCmin (p < 0.001) values than wild type, regardless of tumor histology and location. ROC analysis demonstrated similar performances between these parameters in predicting BRAF V600E status (rADCmean: AUC 0.831, p < 0.001; rADCmin: AUC 0.885, p < 0.001). No significant differences regarding additional imaging features emerged between BRAF V600E-mutant and wild-type lesions, with the exception of the number of tumors with cystic components, significantly higher in BRAF V600E-mutant PAs (p = 0.011) CONCLUSION: Assessment of the DWI characteristics of GGs and PAs may assist in predicting BRAF V600E status, suggesting a radiogenomic correlation and prompt molecular characterization of these tumors.

Advanced MR imaging and 18F-DOPA PET characteristics of H3K27M-mutant and wild-type pediatric diffuse midline gliomas.

PURPOSE: The aim of this study was to investigate MRI-derived diffusion weighted imaging (DWI), 1H-MR spectroscopy (1H-MRS) and arterial spin labeling (ASL) perfusion imaging in comparison with 18F-dihydroxyphenylalanine (DOPA) PET with respect to diagnostic evaluation of pediatric diffuse midline gliomas (DMG) H3K27M-mutant and wild-type. METHODS: We retrospectively analyzed 22 pediatric patients with DMG histologically proved and molecularly classified as H3K27M-mutant (12 subjects) and wild-type (10 subjects) who underwent DWI, 1H-MRS, and ASL performed within 2 weeks of 18F-DOPA PET. DWI-derived relative minimum apparent diffusion coefficient (rADC min), 1H-MRS data [choline/N-acetylaspartate (Cho/NAA), choline/creatine (Cho/Cr), and presence of lactate] and relative ASL-derived cerebral blood flow max (rCBF max) were compared with 18F-DOPA uptake Tumor/Normal tissue (T/N) and Tumor/Striatum (T/S) ratios, and correlated with histological and molecular features of DMG. Statistics included Pearson's chi-square and Mann-Whitney U tests, Spearman's rank correlation and receiver operating characteristic (ROC) analysis. RESULTS: The highest degrees of correlation among different techniques were found between T/S, rADC min and Cho/NAA ratio (p < 0.01), and between rCBF max and rADC min (p < 0.01). Significant differences between histologically classified low- and high-grade DMG, independently of H3K27M-mutation, were found among all imaging techniques (p ≤ 0.02). Significant differences in terms of rCBF max, rADC min, Cho/NAA and 18F-DOPA uptake were also found between molecularly classified mutant and wild-type DMG (p ≤ 0.02), even though wild-type DMG included low-grade astrocytomas, not present among mutant DMG. When comparing only histologically defined high-grade mutant and wild-type DMG, only the 18F-DOPA PET data T/S demonstrated statistically significant differences independently of histology (p < 0.003). ROC analysis demonstrated that T/S ratio was the best parameter for differentiating mutant from wild-type DMG (AUC 0.94, p < 0.001). CONCLUSIONS: Advanced MRI and 18F-DOPA PET characteristics of DMG depend on histological features; however, 18F-DOPA PET-T/S was the only parameter able to discriminate H3K27M-mutant from wild-type DMG independently of histology.

T2*-based MR imaging (gradient echo or susceptibility-weighted imaging) in midline and off-midline intracranial germ cell tumors: a pilot study.

PURPOSE: The role of T2*-based MR imaging in intracranial germ cell tumors (GCTs) has not been fully elucidated. The aim of this study was to evaluate the susceptibility-weighted imaging (SWI) or T2* gradient echo (GRE) features of germinomas and non-germinomatous germ cell tumors (NGGCTs) in midline and off-midline locations. METHODS: We retrospectively evaluated all consecutive pediatric patients referred to our institution between 2005 and 2016, for newly diagnosed, treatment-naïve intracranial GCT, who underwent MRI, including T2*-based MR imaging (T2* GRE sequences or SWI). Standard pre- and post-contrast T1- and T2-weighted imaging characteristics along with T2*-based MR imaging features of all lesions were evaluated. Diagnosis was performed in accordance with the SIOP CNS GCT protocol criteria. RESULTS: Twenty-four subjects met the inclusion criteria (17 males and 7 females). There were 17 patients with germinomas, including 5 basal ganglia primaries, and 7 patients with secreting NGGCT. All off-midline germinomas presented with SWI or GRE hypointensity; among midline GCT, all NGGCTs showed SWI or GRE hypointensity whereas all but one pure germinoma were isointense or hyperintense to normal parenchyma. A significant difference emerged on T2*-based MR imaging among midline germinomas, NGGCTs, and off-midline germinomas (p < 0.001). CONCLUSION: Assessment of the SWI or GRE characteristics of intracranial GCT may potentially assist in differentiating pure germinomas from NGGCT and in the characterization of basal ganglia involvement. T2*-based MR imaging is recommended in case of suspected intracranial GCT.

Neuroendocrine late effects after tailored photon radiotherapy for children with low grade gliomas: Long term correlation with tumour and treatment parameters.

PURPOSE: To evaluate neuroendocrine late effects in paediatric patients with low grade glioma (LGG) who underwent radiotherapy. METHODS AND MATERIAL: We performed a retrospective evaluation of 40 children with LGG treated from July 2002 to January 2015 with external radiotherapy. Tumour locations were cerebral hemisphere (n=2); posterior fossa (n=15); hypothalamic-pituitary axis (HPA, n=15); spine (n=5). Three patients presented a diffuse disease. We looked for a correlation between endocrine toxicity and tumour and treatment parameters. The impact of some clinical and demographic factors on endocrinal and neuro toxicity was evaluated using the log-rank test. RESULTS: The median follow-up was 52months (range: 2-151). Median age at irradiation was 6. The dose to the HPA was significantly associated with endocrine toxicity (P value=0.0190). Patients who received chemotherapy before radiotherapy and younger patients, showed worse performance status and lower IQ. The 5-year overall survival (OS) and progression free survival (PFS) rates were 94% and 73.7%, respectively. CONCLUSION: Radiotherapy showed excellent OS and PFS rates and acceptable late neuroendocrine toxicity profile in this population of LGG patients treated over a period of 13years. In our experience, the dose to the HPA was predictive of the risk of late endocrine toxicity.