Response in a child with a BRAF V600E mutated desmoplastic infantile astrocytoma upon retreatment with vemurafenib.

Infants with low-grade glioma (LGG) and diencephalic syndrome have a poor outcome. The patient described here had a desmoplastic infantile astrocytoma harboring a BRAF V600E mutation. After relapse following initial standard chemotherapy treatment, he was successfully treated with the BRAF V600E inhibitor vemurafenib at the age of 3 years 11 months and 5 years 0 months. A rapid response was observed on both occasions. This illustrates the possibility of continuous oncogenic addiction and the therapeutic potential of BRAF V600E inhibitor monotherapy in LGG, even in very young severely compromised children. BRAF V600E inhibition in LGG and possible (re-)treatment regimens are briefly discussed.

Molecular Diagnostics in Pediatric Brain Tumors: Impact on Diagnosis and Clinical Decision-Making - A Selected Case Series.

Central nervous system (CNS) tumors account for the highest mortality among pediatric malignancies. Accurate diagnosis is essential for optimal clinical management. The increasing use of molecular diagnostics has opened up novel possibilities for more precise classification of CNS tumors. We here report a single-institutional collection of pediatric CNS tumor cases that underwent a refinement or a change of diagnosis after completion of molecular analysis that affected clinical decision-making including the application of molecularly informed targeted therapies. 13 pediatric CNS tumors were analyzed by conventional histology, immunohistochemistry, and molecular diagnostics including DNA methylation profiling in 12 cases, DNA sequencing in 8 cases and RNA sequencing in 3 cases. 3 tumors had a refinement of diagnosis upon molecular testing, and 6 tumors underwent a change of diagnosis. Targeted therapy was initiated in 5 cases. An underlying cancer predisposition syndrome was detected in 5 cases. Although this case series, retrospective and not population based, has its limitations, insight can be gained regarding precision of diagnosis and clinical management of the patients in selected cases. Accuracy of diagnosis was improved in the cases presented here by the addition of molecular diagnostics, impacting clinical management of affected patients, both in the first-line as well as in the follow-up setting. This additional information may support the clinical decision making in the treatment of challenging pediatric CNS tumors. Prospective testing of the clinical value of molecular diagnostics is currently underway.

Combination of Sturge-Weber Syndrome and Trigonocephaly.

Regarded singly, both Sturge-Weber syndrome and trigonocephaly are rare congenital disorders. The cardinal features of Sturge-Weber syndrome are facial cutaneous capillary malformation (port-wine stain), leptomeningeal angiomatosis, and glaucoma. Premature closure of the metopic suture results in trigonocephaly. However, to the best of our knowledge, the diagnosis of a combination of both Sturge-Weber syndrome and trigonocephaly has not as yet been reported. This brief clinical study thus presents a patient with the unusual findings of a Sturge-Weber syndrome and simultaneous trigonocephaly induced by premature metopic synostosis. Thus, the rare combination of a port-wine stain involving the first division of the trigeminal nerve with the diagnosis of a craniosynostosis justifies the indication of a prophylactic magnetic resonance imaging acquisition before craniofacial surgeries, in order to prevent seizures and stroke-like episodes triggered by the surgical intervention.

Brainstem biopsy in pediatric diffuse intrinsic pontine glioma in the era of precision medicine: the INFORM study experience.

PURPOSE: Diffuse intrinsic pontine glioma (DIPG) is a highly aggressive paediatric brain tumour with fatal outcome. The Individualised Therapy For Relapsed Malignancies In Childhood (INFORM) registry study offers comprehensive molecular profiling of high-risk tumours to identify target alterations for potential precision therapy. We analysed molecular characteristics and clinical data after brainstem biopsy of all enrolled newly diagnosed DIPGs. PATIENTS AND METHODS: From -February 2015 to February 2018, 21 subsequent primary DIPG cases were enrolled in the nation-wide multicentre INFORM registry study after brainstem biopsy. Whole-genome, whole-exome sequencing and DNA methylation analysis were performed, and RNA-sequencing was added in case of sufficient material. Clinical data were obtained from standardised questionnaires and the INFORM clinical data bank. RESULTS: Tumour material obtained from brainstem biopsy was sufficient for DNA analysis in all cases and RNA analysis in 16 of 21 cases. In 16 of 21 cases (76%), potential targetable alterations were identified including highly relevant MET and NTRK1 fusions as well as an EZH2 alteration not previously described in DIPG. In 5 of 21 cases, molecular information was used for initiation of targeted treatment. The majority of patients (19/21) presented with neurological deficits at diagnosis. Newly arising or worsening of neurological deficits post-biopsy occurred in nine patients. Symptoms were reversible or improved notably in eight cases. CONCLUSION: In this multicentre study setting, brainstem biopsy of DIPG was feasible and yielded sufficient material for comprehensive molecular profiling. Relevant molecular targets were identified impacting clinical management in a substantial subset. Death or severe bleeding occurred in none of the cases. One of 20 patients experienced unilateral paraesthesia possibly related to biopsy.

Increased water temperature renders single-housed C57BL/6J mice susceptible to antidepressant treatment in the forced swim test.

To investigate genotype x environment interactions in the forced swim test, we tested the influence of water temperature (20 degrees C, 25 degrees C, 30 degrees C) on floating behaviour in single-housed male C57BL/6J and BALB/c mice. We observed a contrasting relationship between floating and water temperature between the two strains, with C57BL/6J floating more and BALB/c floating less with increasing water temperature, independent of the lightening conditions and the time point of testing during the animals' circadian rhythm. Both strains showed an inverse relationship between plasma corticosterone concentration and water temperature, indicating that the differences in stress coping are unrelated to different perception of the aversive encounter. Treatment with desipramine (20mg/kg, i.p.) caused a reduction in immobility time in C57BL/6J mice if the animals were tested at 30 degrees C water temperature, with no effect at 25 degrees C and no effects on forced swim stress-induced corticosterone secretion. The same treatment failed to affect floating behaviour in BALB/c at any temperature, but caused a decrease in plasma corticosterone levels. Taken together we demonstrate that an increase in water temperature in the forced swim test exerts opposite effects on floating behaviour in C57BL/6J and BALB/c and renders single-housed C57BL/6J mice, but not BALB/c mice, susceptible to antidepressant-like behavioral effects of desipramine.

Chiari-like displacement due to spontaneous intracranial hypotension in an adolescent: Successful treatment by epidural blood patch.

BACKGROUND: Spontaneous intracranial hypotension is a rarely diagnosed cause of headache, especially in children and adolescents. It is due to cerebrospinal fluid (CSF) leakage via spinal fistulae occurring without major trauma. CASE PRESENTATION: An adolescent patient presented with a 3-month history of strictly postural headache. Cranial magnetic resonance imaging (MRI) showed pronounced Chiari-like prolapse of the cerebellar tonsils, narrow ventricles and enlarged cerebral veins. On spinal MRI, myelographic sequences revealed a large collection of CSF around the first sacral roots. CT myelography proved extensive spinal CSF leakage. Hence, we applied epidural patches at multiple levels. Afterwards, symptoms and radiologic findings, including Chiari-like displacement, completely resolved. CONCLUSION: A Chiari-like descent of the cerebellar tonsils alone does not secure the diagnosis of a Chiari I malformation. Especially if other findings indicate spinal CSF leakage, a systematic work-up should be initiated. In most cases, interventional techniques seal the leak successfully, resulting in a favorable outcome.

Establishment and application of a novel patient-derived KIAA1549:BRAF-driven pediatric pilocytic astrocytoma model for preclinical drug testing.

Pilocytic astrocytoma (PA) is the most frequent pediatric brain tumor. Activation of the MAPK pathway is well established as the oncogenic driver of the disease. It is most frequently caused by KIAA1549:BRAF fusions, and leads to oncogene induced senescence (OIS). OIS is thought to be a major reason for growth arrest of PA cells in vitro and in vivo, preventing establishment of PA cultures. Hence, valid preclinical models are currently very limited, but preclinical testing of new compounds is urgently needed. We transduced the PA short-term culture DKFZ-BT66 derived from the PA of a 2-year old patient with a doxycycline-inducible system coding for Simian Vacuolating Virus 40 Large T Antigen (SV40-TAg). SV40-TAg inhibits TP53/CDKN1A and CDKN2A/RB1, two pathways critical for OIS induction and maintenance. DNA methylation array and KIAA1549:BRAF fusion analysis confirmed pilocytic astrocytoma identity of DKFZ-BT66 cells after establishment. Readouts were analyzed in proliferating as well as senescent states, including cell counts, viability, cell cycle analysis, expression of SV40-Tag, CDKN2A (p16), CDKN1A (p21), and TP53 (p53) protein, and gene-expression profiling. Selected MAPK inhibitors (MAPKi) including clinically available MEK inhibitors (MEKi) were tested in vitro. Expression of SV40-TAg enabled the cells to bypass OIS and to resume proliferation with a mean doubling time of 45h allowing for propagation and long-term culture. Withdrawal of doxycycline led to an immediate decrease of SV40-TAg expression, appearance of senescent morphology, upregulation of CDKI proteins and a subsequent G1 growth arrest in line with the re-induction of senescence. DKFZ-BT66 cells still underwent replicative senescence that was overcome by TERT expression. Testing of a set of MAPKi revealed differential responses in DKFZ-BT66. MEKi efficiently inhibited MAPK signaling at clinically achievable concentrations, while BRAF V600E- and RAF Type II inhibitors showed paradoxical activation. Taken together, we have established the first patient-derived long term expandable PA cell line expressing the KIAA1549:BRAF-fusion suitable for preclinical drug testing.

Ventriculo-bipleural shunt as last resort in a 4-year-old child in whom a VP and VA shunt failed.

The authors present the unusual case of a 4-year-old boy who had a complex history of posthemorrhagic hydrocephalus and who underwent more than 40 surgeries related to this condition. In the course of trying to treat his condition, ventriculoperitoneal, ventriculoatrial, and ventriculopleural shunts were inserted and failed. The child presented with a dysfunction of his shunt system. A ventriculopleural shunt was inserted, but within days the patient developed dyspnea as a clinical symptom of pleural effusion that required repeated thoracentesis. A bipleural drainage system was inserted, and no relevant pleural effusions developed during the follow-up period. Although the authors' experience is based on a single case, they do suggest bipleural drainage in patients with clinically relevant pleural effusions when the more common alternatives are not a good choice. Bipleural drainage might particularly be an option in children, who are prone to pleural effusion because of the smaller absorbing pleural surface. The authors reviewed the English-language literature on PubMed dating back to 1952. To their knowledge, this is the only published case in which a patient was treated with a ventriculo-bipleural shunt.

Metopic synostosis: Measuring intracranial volume change following fronto-orbital advancement using three-dimensional photogrammetry.

There is still disagreement regarding the intracranial volumes of patients with metopic synostosis compared with healthy patients. This study aimed to compare the intracranial volume of children with metopic synostosis before and after surgery to an age- and sex-matched control cohort using three-dimensional (3D) photogrammetry. Eighteen boys with metopic synostosis were operated on using standardized fronto-orbital advancement. Frontal, posterior and total intracranial volumes were measured exactly 1 day pre-operatively and 10 days post-operatively, using 3D photogrammetry. To establish an age- and sex-matched control group, the 3D photogrammetric data of 634 healthy boys between the ages of 3 and 13 months were analyzed. Mean age at surgery was 9 months (SD 1.7). Prior to surgery, boys with metopic synostosis showed significantly reduced frontal and total intracranial volumes compared with the reference group, but similar posterior volumes. After surgery, frontal and total intracranial volumes did not differ statistically from the control group. As children with metopic synostosis showed significantly smaller frontal and total intracranial volumes compared with an age- and sex-matched control group, corrective surgery should aim to achieve volume expansion. Furthermore, 3D photogrammetry provides a valuable alternative to CT scans in the measurement of intracranial volume in children with metopic synostosis, which significantly reduces the amount of radiation exposure to the growing brain.

Strain differences in profiles of dopaminergic neurotransmission in the prefrontal cortex of the BALB/C vs. C57Bl/6 mice: consequences of stress and afobazole.

We found that in mice the basal activity of monoamine oxidase B (MAO-B) in the medial prefrontal cortex (mPFC) is lower in BALB/C than in C57Bl/6J mice, whereas activity of MAO-A is similar between strains. BALB/C mice, in comparison to C57Bl/6N mice, have higher basal content of dopamine in the mPFC, in both microdialysates and tissue content. Novelty stress (open field test) elicits a further increase in the microdialysate levels of dopamine in BALB/C, but not in C57Bl/6N mice; a subsequent accumulation of extracellular 3,4-dioxyphenylacetic acid (DOPAC) reaffirms the difference in catabolic capacity of monoaminergic systems between the strains. We demonstrated that in stress-susceptible BALB/C mice the novel anxiolytic afobazole, 5mg/kg, selectively mitigates trait anxiety; however it does not change the behavioral response in stress-resilient C57Bl/6N mice. Afobazole inhibits MAO-A in in vitro; it also lowers the microdialysate DOPAC levels in both strains (which testifies to its MAO-A inhibiting activity in vivo) and slightly suppresses dopamine release when elevated. Therefore, it is likely that the drug may mediate its anxiolytic activity via modulation of volume dopaminergic transmission at level of the mPFC.

Skull base and maxillofacial fractures: two centre study with correlation of clinical findings with a comprehensive craniofacial classification system.

PURPOSE: A comprehensive classification based on high resolution computed tomography (CT) of the whole craniofacial region was correlated with clinical findings of combined skull base and maxillofacial fractures. MATERIAL AND METHODS: In a study of two clinical centres, 70 patients with such injuries were admitted at the Universities of Basel (n=29) and Uppsala (n=41). Clinical signs (rhinorrhoea, periorbital haematoma and pneumencephalus) and surgical versus conservative treatment were correlated with a cranio-maxillofacial injury severity score (CMF-ISS) calculated from the classification system. Fracture classifications were decided in consensus on the basis of CT and semiautomatic classification software. The classification system defined 3 fracture types (A, B, C), 3 groups (A1, A2, A3), and 3 subgroups (A1.1, A1.2, A1.3) with increasing severity from A1.1 (lowest) to C3.3 (highest). RESULTS: Of 70 patients, 43 were operated upon and 27 conservatively treated. The operated patients had significantly higher severity scores than non-operated. Patients with or without periorbital haematoma do not differ significantly in the severity score. The severity of the CMF-ISS score was significantly associated (two sample T-test P<0.01) with the occurrence of pneumencephalus, rhinorrhoea and treatment approach. CONCLUSION: Based on our present results, this system seems to be clinical useful for operative decisions and interventions.

Therapeutic strategies and management of desmoplastic infantile ganglioglioma: two case reports and literature overview.

INTRODUCTION: Desmoplastic infantile gangliogliomas (DIG) are rare cerebral glioneural tumors usually occurring in early childhood. DIGs are generally benign although rare cases with poor outcome are known. Total resection, if possible, is the treatment of choice, without further adjuvant therapy. After incomplete resection, adjuvant chemo-and/or radiotherapy is generally applied, despite the potential negative side effects in such young patients. CASE REPORTS: We describe two girls with DIG, one who twice underwent subtotal resection at 3 and 5 months, the other who underwent total resection at 2 years. Neither had adjuvant therapy and there was no tumor recurrence. CONCLUSIONS: Our own experience and a review of the literature suggest that in most DIGs adjuvant therapy is not justified even after incomplete resection. After tumor recurrence a second surgical intervention should be considered instead of adjuvant therapy. An exception may be made for rare, deep-seated DIGs, which are more aggressive and have a poorer outcome.

Cerebral toxocariasis: a possible cause of epileptic seizure in children.

INTRODUCTION: Toxocariasis is a worldwide human helminthiasis, which is mostly asymptomatic and caused by toxocara canis, a roundworm in dogs. These can cause visceral larva migrans syndrome in humans who ingest contaminated soil. CNS manifestation with a focal mass lesion is very rare, seizures often being the first symptom. CASE REPORT: We describe an 11-year-old girl presenting with a generalized epileptic seizure and eosinophilia in blood. Under antibiotic therapy under the assumption of toxoplasmosis the lesion did not decrease and surgical resection was considered. We used computer-assisted surgery (CAS) for careful tissue resection. Postoperatively the diagnosis of toxocariasis was confirmed and albendozole medication was administered for 7 days. The patient developed well without neurological deficits or seizures. CONCLUSION: We conclude that although neurological involvement is rare in toxocariasis, a cerebral infection in a child with epileptic seizures and eosinophilia should be considered.