Staged neurosurgical approach for giant and progressive neonatal arachnoid cysts: a case series and review of the literature

OBJECTIVES

Prenatally diagnosed complex arachnoid cysts are very rare. While the true prenatal incidence is still unknown, they account for approximately 1% of intracranial masses in newborns. They rarely exhibit rapid growth or cause obstructive hydrocephalus, but if they increase to such a dimension during pregnancy, the ideal management is not well established. We present our detailed perinatal experience, covering prenatal diagnosis, a compassionate delivery process, and neonatal stabilization. Finally, a thorough postnatal neurosurgical intervention was performed. Initially, our focus was on the gradual reduction of cyst size as a primary effort, followed by subsequent definitive surgical treatment.

METHODS

This case series shows the treatment course of three fetuses with antenatally diagnosed large arachnoid cysts. We present pre- and postnatal management and imaging, as well as the surgical treatment plan and the available clinical course during follow-up.

RESULTS

Two girls and one boy were included in the current review. All three cases presented with prenatally diagnosed complex arachnoid cysts that increased in size during pregnancy. The mean gestational age at delivery was 35 weeks (range 32 to 37 weeks), and all patients were delivered by a caesarian section. Increasing head circumference and compression of brain structures were indications for delivery, as they are associated with a high risk of excess intracranial pressures and CSF diapedesis, as well as traumatic delivery and maternal complications. All cysts were supratentorial in location; one expanded into the posterior fossa, and one was a multicompartment cyst. All children underwent an initial surgical procedure within the first days of life. To relieve cyst pressure and achieve a reduction in head circumference, an ultrasound-guided or endoscopic-assisted internal shunt with drainage of the cyst to the ventricles or subdural/subarachnoid space was inserted. Definite surgical therapy consisted of cyst marsupialization and/or cysto-peritoneal shunt implantation. All children survived without severe neurodevelopmental impairments.

CONCLUSION

With the cases presented, we demonstrate that the slow reduction of immense cyst size as an initial procedure until optimal requirements for final surgical treatment were achieved has proven to be optimal for neurological outcome. Special emphasis has to be taken on the delicate nature of premature newborn babies, and surgical steps have to be thoroughly considered within the interdisciplinary team.

Controversies in the Treatment of Arachnoid Cysts with Special Emphasis on Temporal Arachnoid Cysts

Intracranial arachnoid cysts (ACs) are benign lesions. The incidence in children is 2.6%. ACs are often diagnosed incidentally. Because of the broad use of CT and MR imaging, the frequency of AC diagnosis has increased. In addition, prenatal diagnosis of ACs is becoming more common. This places clinicians in a difficult situation with regard to the optimal treatment, since the presenting symptoms are often vague and operative management includes not negligible risks. It is generally accepted that conservative management is indicated in cases with small and asymptomatic cysts. In contrast, patients with definite signs of raised intracranial pressure should be treated. There are however clinical situations in whom the decision about the preferred treatment is difficult to make. Unspecific symptoms such as headaches and neurocognitive or attention deficits can be challenging to evaluate, whether they are related to the presence of the AC or not. The treatment techniques intent to establish a communication between the cyst and the normal cerebrospinal spaces or consist of a diversion of the cyst fluid by a shunt system. Which surgical method (open craniotomy for cyst fenestration, endoscopic fenestration, or shunting) is preferred differs between neurosurgical centers or the pediatric neurosurgeon in charge. Each treatment option has a unique profile of advantages and disadvantages which should be considered when discussing treatment with the patients or their caregivers.

EXTH-86. BH3 PROFILING IDENTIFIES ONC201/TIC10 AS A PROMISING PARTNER OF ABT-263 IN MEDULLOBLASTOMA IN VITRO

OBJECTIVE

Medulloblastoma represents one of the most common brain tumors in children. In this study, we identified by BH3 profiling that ONC201/TIC10 sensitizes for Bcl-xL/Bcl-2 inhibition in medulloblastoma and performed a preclinical testing of a combined treatment with ONC201/TIC10 and the Bcl-xL/Bcl-2 inhibitor ABT-263.

METHODS

BH3 profiling was performed to examine ONC201/TIC10-mediated dependencies on anti-apoptotic Bcl-2 family proteins. The combination treatment with ONC201/TIC10 and ABT-263 was tested in different medulloblastoma cells using MTT assays. Isobolograms were calculated to characterize the drug-drug interaction. Tumor spheroid and chorioallantoic membrane assays were used to examine the effects of the combination therapy in a 3D setting. Annexin V/PI staining and flowcytometry were used to detect pro-apoptotic effects. Western blot analyses and knockdown experiments with siRNA were performed for molecular analysis. Extracellular flux analyses served at examining effects on the tumor cell metabolism.

RESULTS

BH3 profiling showed that ONC201/TIC10 sensitizes medulloblastoma cells to Bcl-xL/Bcl-2 inhibition. In line with this finding, combined treatment with ONC201/TIC10 and ABT-263 led to a predominantly synergistic inhibitory effect on the cell viability of established (D425, D458, DAOY, HD-MB03), primary cultured (PC322) and stem-like (SC322) medulloblastoma cells in 2D and 3D models. The response towards the combination therapy was independent of baseline c-myc expression. On the molecular level, treatment with ONC201/TIC10 led to a dose-dependent decrease of Mcl-1. Moreover, the combination caused enhanced cleavage of caspases 9 and 3. On the metabolic level, the combination therapy led to a reduction in both, oxidative phosphorylation and the glycolytic rate and a reduced expression of respiratory chain proteins.

CONCLUSION

Combined treatment with ONC201/TIC10 and ABT-263 had a predominantly synergistic inhibitory effect on the cell viability of medulloblastoma cells. This effect was associated with downregulation of Mcl-1. Moreover, the combination treatment resulted in a metabolic reprogramming which likely creates a state of energy deprivation.

Bcl-XL but Not Bcl-2 Is a Potential Target in Medulloblastoma Therapy

Medulloblastoma (MB) is the most common solid tumour in children and, despite current treatment with a rather aggressive combination therapy, accounts for 10% of all deaths associated with paediatric cancer. Breaking the tumour cells’ intrinsic resistance to therapy-induced cell death should lead to less aggressive and more effective treatment options. In other tumour entities, this has been achieved by modulating the balance between the various pro- and anti-apoptotic members of the Bcl-2 family with small molecule inhibitors. To evaluate the therapeutic benefits of ABT-199 (Venetoclax), a Bcl-2 inhibitor, and ABT-263 (Navitoclax), a dual Bcl-XL/Bcl-2 inhibitor, increasingly more relevant model systems were investigated. Starting from established MB cell lines, progressing to primary patient-derived material and finally an experimental tumour system imbedded in an organic environment were chosen. Assessment of the metabolic activity (a surrogate readout for population viability), the induction of DNA fragmentation (apoptosis) and changes in cell number (the combined effect of alterations in proliferation and cell death induction) revealed that ABT-263, but not ABT-199, is a promising candidate for combination therapy, synergizing with cell death-inducing stimuli. Interestingly, in the experimental tumour setting, the sensitizing effect of ABT-263 seems to be predominantly mediated via an anti-proliferative and not a pro-apoptotic effect, opening a future line of investigation. Our data show that modulation of specific members of the Bcl-2 family might be a promising therapeutic addition for the treatment of MB.

ONC201/TIC10 Is Empowered by 2-Deoxyglucose and Causes Metabolic Reprogramming in Medulloblastoma Cells in Vitro Independent of C-Myc Expression

The purpose of this study was to examine whether the imipridone ONC201/TIC10 affects the metabolic and proliferative activity of medulloblastoma cells in vitro. Preclinical drug testing including extracellular flux analyses (agilent seahorse), MTT assays and Western blot analyses were performed in high and low c-myc-expressing medulloblastoma cells. Our data show that treatment with the imipridone ONC201/TIC10 leads to a significant inihibitory effect on the cellular viability of different medulloblastoma cells independent of c-myc expression. This effect is enhanced by glucose starvation. While ONC201/TIC10 decreases the oxidative consumption rates in D458 (c-myc high) and DAOY (c-myc low) cells extracellular acidification rates experienced an increase in D458 and a decrease in DAOY cells. Combined treatment with ONC201/TIC10 and the glycolysis inhibitor 2-Deoxyglucose led to a synergistic inhibitory effect on the cellular viability of medulloblastoma cells including spheroid models. In conclusion, our data suggest that ONC201/TIC10 has a profound anti-proliferative activity against medulloblastoma cells independent of c-myc expression. Metabolic targeting of medulloblastoma cells by ONC201/TIC10 can be significantly enhanced by an additional treatment with the glycolysis inhibitor 2-Deoxyglucose. Further investigations are warranted.

Lamina cribrosa perforation during nasotracheal intubation in neonates: case series and review of the literature

Intracranial penetration during attempted nasotracheal intubation is a potentially devastating complication, which should be carefully evaluated and the risk should be addressed in neonatal resuscitation trainings.

Development and assessment of competency-based neurotrauma course curriculum for international neurosurgery residents and neurosurgeons

OBJECTIVE

Traumatic brain injuries (TBIs) are a significant disease burden worldwide. It is imperative to improve neurosurgeons' training during and after their medical residency with appropriate neurotrauma competencies. Unfortunately, the development of these competencies during neurosurgeons' careers and in daily practice is very heterogeneous. This article aimed to describe the development and evaluation of a competency-based international course curriculum designed to address a broad spectrum of needs for taking care of patients with neurotrauma with basic and advanced interventions in different scenarios around the world.

METHODS

A committee of 5 academic neurosurgeons was involved in the task of building this course curriculum. The process started with the identification of the problems to be addressed and the subsequent performance needed. After this, competencies were defined. In the final phase, educational activities were designed to achieve the intended learning outcomes. In the end, the entire process resulted in competency and outcomes-based education strategy, including a definition of all learning activities and learning outcomes (curriculum), that can be integrated with a faculty development process, including training. Further development was completed by 4 additional academic neurosurgeons supported by a curriculum developer specialist and a project manager. After the development of the course curriculum, template programs were developed with core and optional content defined for implementation and evaluation.

RESULTS

The content of the course curriculum is divided into essentials and advanced concepts and interventions in neurotrauma care. A mixed sample of 1583 neurosurgeons and neurosurgery residents attending 36 continuing medical education activities in 30 different cities around the world evaluated the course. The average satisfaction was 97%. The average usefulness score was 4.2, according to the Likert scale.

CONCLUSIONS

An international competency-based course curriculum is an option for creating a well-accepted neurotrauma educational process designed to address a broad spectrum of needs that a neurotrauma practitioner faces during the basic and advanced care of patients in different regions of the world. This process may also be applied to other areas of the neurosurgical knowledge spectrum. Moreover, this process allows worldwide standardization of knowledge requirements and competencies, such that training may be better benchmarked between countries regardless of their income level.

Congruence and Discrepancy of Interictal and Ictal EEG With MRI Lesions in Pediatric Epilepsies

Purpose. To evaluate the congruence or discrepancy of the localization of magnetic resonance imaging (MRI) lesions with interictal epileptiform discharges (IEDs) or epileptic seizure patterns (ESPs) in surface EEG in lesional pediatric epilepsy patients. Methods. We retrospectively analyzed presurgical MRI and video-EEG monitoring findings of patients up to age 18 years. Localization of MRI lesions were compared with ictal and interictal noninvasive EEG findings of patients with frontal, temporal, parietal, or occipital lesions. Results. A total of 71 patients were included. Localization of ESPs showed better congruence with MRI in patients with frontal lesions (n = 21, 77.5%) than in patients with temporal lesions (n = 24; 40.7%) (P = .009). No significant IED distribution differences between MRI localizations could be found. Conclusions. MRI lesions and EEG findings are rarely fully congruent. Congruence of MRI lesions and ESPs was highest in children with frontal lesions. This is in contrast to adults, in whom temporal lesions showed the highest congruency with the EEG localization of ESP. Lesional pediatric patients should be acknowledged as surgical candidates despite incongruent findings of interictal and ictal surface EEG.

On-site CAD templates reduce surgery time for complex craniostenosis repair in infants: a new method

INTRODUCTION

The surgical correction of craniostenosis in children is a time-consuming and taxing procedure. To facilitate this procedure, especially in infants with complex craniostenosis, we refined the computer-aided design and manufacturing technique (CAD/CAM) based on computed tomography (CT)-generated DICOM data. We used cutting guides and molding templates, which allowed the surgeon to reshape and fixate the supraorbital bar extracorporeally on a side table and to control the intracorporal fit without removing the template.

METHOD AND PATIENTS

To compare our traditional concept with the possibility of preoperative virtual planning (PVP) technique, the surgical treatment and courses of 16 infants with complex craniostenosis following fronto-orbital advancement (FOA) (age range 8-15 months) were analyzed in two groups (group 1: traditional, control group n = 8, group 2: CAD/CAM planned, n = 8).

RESULTS

While in both groups, the head accurately reshaped postoperatively during the follow-up; the CAD group 2 showed a significantly shorter operating time with a mean of 4 h 25 min compared with group 1 with a mean of 5 h 37 min (p = 0.038). Additionally, the CAD group 2 had a significantly lower volume of blood loss (380 ml vs. 575 ml mean, p = 0.047), lower blood transfusion volume (285 ml vs. 400 ml mean, p = 0.108), lower fresh frozen plasma (FFP) volume (140 ml vs. 275 ml mean, p = 0.019), shorter stay in the pediatric intensive care unit (PICU) (3 vs. 5 days mean (p = 0.002), and shorter total length of hospital stay (6 days vs. 8 days mean, p = 0.002).

CONCLUSION

CAD/CAM cutting guides and templates offer optimizing operative efficiency, precision, and accuracy in craniostenosis surgery in infants. As shown in this single-center observational study, the use of on-site templates significantly accelerates the reconstruction of the bandeau. The virtual 3D planning technique increases surgical precision without discernible detrimental effects.

Compare and contrast: pediatric cancer versus adult malignancies

Cancer is a leading cause of death in both adults and children, but in terms of absolute numbers, pediatric cancer is a relatively rare disease. The rarity of pediatric cancer is consistent with our current understanding of how adult malignancies form, emphasizing the view of cancer as a genetic disease caused by the accumulation and selection of unrepaired mutations over time. However, considering those children who develop cancer merely as stochastically "unlucky" does not fully explain the underlying aetiology, which is distinct from that observed in adults. Here, we discuss the differences in cancer genetics, distribution, and microenvironment between adult and pediatric cancers and argue that pediatric tumours need to be seen as a distinct subset with their own distinct therapeutic challenges. While in adults, the benefit of any treatment should outweigh mostly short-term complications, potential long-term effects have a much stronger impact in children. In addition, clinical trials must cope with low participant numbers when evaluating novel treatment strategies, which need to address the specific requirements of children.

Childhood haemorrhagic stroke: a 7-year single-centre experience

BACKGROUND

In recent years, there has been increasing research interest in improving diagnostic and management protocols in childhood arterial ischaemic stroke (AIS). However, childhood stroke comprises, in approximately equal parts, both arterial ischaemic and haemorrhagic stroke (HS).

OBJECTIVE

The aim of this study was to focus on the aetiology, clinical presentation, treatment and short-term outcome of children with spontaneous intracranial bleeding in a university hospital and elucidate differences to childhood AIS.

DESIGN

We performed a retrospective analysis of electronic medical records of children (28 days-18 years) diagnosed with HS between 2010 and 2016.

RESULTS

We included 25 children (male child, n=11) with a median age of 8 years 1 month. The most common clinical presentations were vomiting (48%), headache (40%) and altered level of consciousness (32%). In more than half of the patients, HS was caused by vascular malformations. Other risk factors were brain tumour, coagulopathy and miscellaneous severe underlying diseases. Aetiology remained unclear in one child. Therapy was neurosurgical in most children (68%). Two patients died, 5 patients needed further (rehabilitation) treatment and 18 children could be discharged home.

CONCLUSIONS

HS differs from AIS in aetiology (vascular malformations as number one risk factor), number of risk factors ('mono-risk' disease), clinical presentation (vomiting, headache and altered level of consciousness) and (emergency) therapy.

Multimodal Imaging in Extratemporal Epilepsy Surgery

Neuroimaging is crucial for the evaluation of patients considered for resective epilepsy surgery. Multimodal image fusion is a new tool to integrate all available localizing information on the individual epileptogenic network in a three-dimensional (3D) manner to plan invasive EEG recordings and delineate the epileptogenic zone from the eloquent cortex for the neurosurgical planning of a tailored resection. Here, we illustrate the multimodal fusion of images from different modalities in a patient with medically intractable non-lesional frontal lobe epilepsy who underwent partial frontal lobe resection, rendering him seizure-free.

Decompression in Chiari Malformation: Clinical, Ocular Motor, Cerebellar, and Vestibular Outcome

BACKGROUND

Treatment of Chiari malformation can include suboccipital decompression with resection of one cerebellar tonsil. Its effects on ocular motor and cerebellar function have not yet been systematically examined.

OBJECTIVE

To investigate whether decompression, including resection of one cerebellar tonsil, leads to ocular motor, vestibular, or cerebellar deficits.

PATIENTS AND METHODS

Ten patients with Chiari malformation type 1 were systematically examined before and after (1 week and 3 months) suboccipital decompression with unilateral tonsillectomy. The work-up included a neurological and neuro-ophthalmological examination, vestibular function, posturography, and subjective scales. Cerebellar function was evaluated by ataxia rating scales.

RESULTS

Decompression led to a major subjective improvement 3 months after surgery, especially regarding headache (5/5 patients), hyp-/dysesthesia (5/5 patients), ataxia of the upper limbs (4/5 patients), and paresis of the triceps and interosseal muscles (2/2 patients). Ocular motor disturbances before decompression were detected in 50% of the patients. These symptoms improved after surgery, but five patients had new persisting mild ocular motor deficits 3 months after decompression with unilateral tonsillectomy (i.e., smooth pursuit deficits, horizontally gaze-evoked nystagmus, rebound, and downbeat nystagmus) without any subjective complaints. Impaired vestibular (horizontal canal, saccular, and utricular) function improved in five of seven patients with impaired function before surgery. Posturographic measurements after surgery did not change significantly.

CONCLUSION

Decompression, including resection of one cerebellar tonsil, leads to an effective relief of patients' preoperative complaints. It is a safe procedure when performed with the help of intraoperative electrophysiological monitoring, although mild ocular motor dysfunctions were seen in half of the patients, which were fortunately asymptomatic.

Walking assessment after lumbar puncture in normal-pressure hydrocephalus: a delayed improvement over 3 days

OBJECTIVE The determination of gait improvement after lumbar puncture (LP) in idiopathic normal-pressure hydrocephalus (iNPH) is crucial, but the best time for such an assessment is unclear. The authors determined the time course of improvement in walking after LP for single-task and dual-task walking in iNPH. METHODS In patients with iNPH, sequential recordings of gait velocity were obtained prior to LP (time point [TP]0), 1-8 hours after LP (TP1), 24 hours after LP (TP2), 48 hours after LP (TP3), and 72 hours after LP (TP4). Gait analysis was performed using a pressure-sensitive carpet (GAITRite) under 4 conditions: walking at preferred velocity (STPS), walking at maximal velocity (STMS), walking while performing serial 7 subtractions (dual-task walking with serial 7 [DTS7]), and walking while performing verbal fluency tasks (dual-task walking with verbal fluency [DTVF]). RESULTS Twenty-four patients with a mean age of 76.1 ± 7.8 years were included in this study. Objective responder status moderately coincided with the self-estimation of the patients with subjective high false-positive results (83%). The extent of improvement was greater for single-task walking than for dual-task walking (p < 0.05). Significant increases in walking speed were found at TP2 for STPS (p = 0.042) and DTVF (p = 0.046) and at TP3 for STPS (p = 0.035), DTS7 (p = 0.042), and DTVF (p = 0.044). Enlargement of the ventricles (Evans Index) positively correlated with early improvement. Gait improvement at TP3 correlated with the shunt response in 18 patients. CONCLUSIONS Quantitative gait assessment in iNPH is important due to the poor self-evaluation of the patients. The maximal increase in gait velocity can be observed 24-48 hours after the LP. This time point is also best to predict the response to shunting. For dual-task paradigms, maximal improvement appears to occur later (48 to 72 hours). Assessment of gait should be performed at Day 2 or 3 after LP.

Early treatment of complex located pediatric low-grade gliomas using iodine-125 brachytherapy alone or in combination with microsurgery

To analyze efficacy, functional outcome, and treatment toxicity of low-dose rate I-125 brachytherapy (SBT) alone or in combination with best safe resection (in case of larger tumor volumes) as first-line treatment for pediatric low-grade gliomas (PLGGs) not suitable for complete resection. Consecutively treated (2000-2014) complex located circumscribed WHO grade I/II PLGGs were included. For small tumors (≤4 cm in diameter) SBT alone was performed; for larger tumors best safe resection and subsequent SBT was chosen. Temporary Iodine-125 seeds were used (median reference dose: 54 Gy). Treatment response was estimated with the modified MacDonald criteria. Analysis of functional outcome included ophthalmological, endocrinological and neurological evaluation. Survival was analyzed with the Kaplan-Meier method. Prognostic factors were obtained from proportional hazards models. Toxicity was categorized according to the Common Terminology Criteria for Adverse Events. Fifty-eight patients were included treated either with SBT alone (n = 39) or with SBT plus microsurgery (n = 19). Five-year progression-free survival was 87%. Two patients had died due to tumor progression. Among survivors, improvement/stabilization/deterioration of functional deficits was seen in 20/14/5 patients, respectively. Complete/partial response had beneficial impact on functional scores (P = 0.02). The 5-year estimated risk to receive adjuvant radiotherapy/chemotherapy was 5.2%. The overall early (delayed) toxicity rate was 8.6% (10.3%), respectively. No permanent morbidity occurred. In complex located PLGGs, early SBT alone or combined with best safe resection preserves/improves functional scores and results in tumor control rates usually achieved with complete resection. Long-term analysis is necessary for confirmation of these results.

Optimized surgical treatment for normal pressure hydrocephalus: comparison between gravitational and differential pressure valves

OBJECTIVES

In idiopathic normal pressure hydrocephalus (NPH) ventriculoperitoneal (VP) shunt insertion is the method of choice to improve cardinal symptoms such as gait disturbance, urge incontinence and/or dementia. With reduced compliance, the brain of the elderly is prone for overdrainage complications. This was especially true with the use of differential pressure valve implantation. The present study compares clinical outcome and complication rates after VP shunt insertion with differential pressure valves in the early years and gravitational valves since 2005.

METHODS

The authors reviewed patients treated at our institution for NPH since 1995. Differential pressure valves were solely used in the initial years, while the treatment regimen changed to gravitational valves in 2005. Clinical improvement/surgical success rates as well as complications were compared between the two groups.

RESULTS

Eighty-nine patients were enrolled for the present study. Mean age at the time of surgery was 73.5 ± 6.3 years. Male patients predominated with 73, compared with 16 female patients. Median follow-up time was 28 ± 26 months. Date of last follow-up was 1st October 2013. Forty-nine patients received a gravitational valve, while 40 were treated with differential pressure valves. In the gravitational group a significant improvement was observed after shunt insertion for gait disorder, cognitive impairment and urge incontinence (p < 0.0001, resp. p = 0.004), while a significant change in the differential pressure group was only seen for gait disorder (p = 0.03) but not for cognition or urinary incontinency (p > 0.05). The risk of hygroma as a sign of shunt overdrainage requiring surgical intervention was significantly higher in the differential pressure group (5 versus 0 in the gravitational group).

CONCLUSIONS

Patients with NPH treated with gravitational valves in the present cohort showed a more profound improvement in their initial symptoms, including gait disorder, cognitive impairment and urinary incontinency without the risk of overdrainage complications requiring surgical intervention when compared with patients who received differential pressure valves in previous years.

Predicting the "usefulness" of 5-ALA-derived tumor fluorescence for fluorescence-guided resections in pediatric brain tumors: a European survey

BACKGROUND

Five-aminolevulinic acid (Gliolan, medac, Wedel, Germany, 5-ALA) is approved for fluorescence-guided resections of adult malignant gliomas. Case reports indicate that 5-ALA can be used for children, yet no prospective study has been conducted as of yet. As a basis for a study, we conducted a survey among certified European Gliolan users to collect data on their experiences with children.

METHODS

Information on patient characteristics, MRI characteristics of tumors, histology, fluorescence qualities, and outcomes were requested. Surgeons were further asked to indicate whether fluorescence was "useful", i.e., leading to changes in surgical strategy or identification of residual tumor. Recursive partitioning analysis (RPA) was used for defining cohorts with high or low likelihoods for useful fluorescence.

RESULTS

Data on 78 patients <18 years of age were submitted by 20 centers. Fluorescence was found useful in 12 of 14 glioblastomas (85 %), four of five anaplastic astrocytomas (60 %), and eight of ten ependymomas grades II and III (80 %). Fluorescence was found inconsistently useful in PNETs (three of seven; 43 %), gangliogliomas (two of five; 40 %), medulloblastomas (two of eight, 25 %) and pilocytic astrocytomas (two of 13; 15 %). RPA of pre-operative factors showed tumors with supratentorial location, strong contrast enhancement and first operation to have a likelihood of useful fluorescence of 64.3 %, as opposed to infratentorial tumors with first surgery (23.1 %).

CONCLUSIONS

Our survey demonstrates 5-ALA as being used in pediatric brain tumors. 5-ALA may be especially useful for contrast-enhancing supratentorial tumors. These data indicate controlled studies to be necessary and also provide a basis for planning such a study.

Use of intrathecal baclofen in children and adolescents: interdisciplinary consensus table 2013

In recent years, intrathecal baclofen (ITB) has attained an important role in the treatment of severe spasticity and dystonia in children. There are principal differences between the use of ITB in children and its use in neurology and oncology in adults. Here, we present a consensus report on best practice for the treatment of severe spastic and dystonic movement disorders with ITB. Using a problem-orientated approach to integrate theories and methods, the consensus was developed by an interdisciplinary group of experienced ITB users and experts in the field of movement disorders involving 14 German centers. On the basis of the data pooled from more than 400 patients, the authors have summarized their experience and supporting evidence in tabular form to provide a concise, but still a comprehensive information base that represents our current understanding regarding ITB treatment options in children and adolescents.

Dynamic regulation of P-glycoprotein in human brain capillaries

Considering its role as a major blood-brain barrier gatekeeper, the dynamic regulation of the efflux transporter P-glycoprotein is of considerable functional relevance. In particular, disease-associated alterations in transport function might affect central nervous system drug efficacy. Thus, targeting regulatory signaling cascades might render a basis for novel therapeutic approaches. Using capillaries freshly prepared from patient tissue resected during epilepsy surgery, we demonstrate dynamic regulation of P-glycoprotein in human brain capillaries. Glutamate proved to up-regulate P-glycoprotein efflux transport in a significant manner via endothelial NMDA receptors. Both inhibition of cyclooxygenase-2 and antagonism at the glycine-binding site of the NMDA receptor prevented the glutamate-mediated induction of P-glycoprotein transport function in human capillaries. In conclusion, the data argue against species differences in the signaling factors increasing endothelial P-glycoprotein transport function in response to glutamate exposure. Targeting of cyclooxygenase-2 and of the NMDA receptor glycine-binding site was confirmed as an efficacious approach to control P-glycoprotein function. The findings might render a basis for translational development of add-on approaches to improve brain penetration and efficacy of drugs.

[Non-invasive estimation of intracranial pressure : MR-based evaluation in children with hydrocephalus]

CLINICAL/METHODICAL ISSUE

The intracranial pressure (ICP) is a crucially important parameter for diagnostic and therapeutic decision-making in patients with hydrocephalus.

STANDARD RADIOLOGICAL METHODS

So far there is no standard method to non-invasively assess the ICP. Various approaches to obtain the ICP semi-invasively or non-invasively are discussed and the clinical application of a magnetic resonance imaging (MRI)-based method to estimate ICP (MR-ICP) is demonstrated in a group of pediatric patients with hydrocephalus.

METHODICAL INNOVATIONS

Arterial inflow, venous drainage and craniospinal cerebrospinal fluid (CSF) flow were quantified using phase-contrast imaging to derive the MR-ICP.

PERFORMANCE

A total of 15 patients with hydrocephalus (n=9 treated with shunt placement or ventriculostomy) underwent MRI on a 3 T scanner applying retrospectively-gated cine phase contrast sequences. Of the patients six had clinical symptoms indicating increased ICP (age 2.5-14.61 years, mean 7.4 years) and nine patients had no clinical signs of elevated ICP (age 2.1-15.9 years; mean 9.8 years; all treated with shunt or ventriculostomy). Median MR-ICP in symptomatic patients was 24.5 mmHg (25th percentile 20.4 mmHg; 75th percentile 44.6 mmHg). Median MR-ICP in patients without acute signs of increased ICP was 9.8 mmHg (25th percentile 8.6 mmHg; 75th percentile 11.4 mmHg). Group differences were significant (p < 0.001; Mann-Whitney U-test).

ACHIEVEMENTS

The MR-ICP technique is a promising non-invasive tool for estimating ICP.

PRACTICAL RECOMMENDATIONS

Further studies in larger patient cohorts are warranted to investigate its application in children with hydrocephalus.

[Hydrocephalus in childhood : causes and imaging patterns]

CLINICAL ISSUE

Causes and imaging patterns of hydrocephalus differ depending on the age of the patient. Traditionally, hydrocephalus was classified into non-communicating and communicating hydrocephalus but more recent classifications also take the site of occlusion and the etiology into account.

DIAGNOSTICS

For the diagnostic work-up computed tomography (CT), sonography and magnetic resonance imaging (MRI) are available and MRI is the method of choice for children and adolescents as it allows determination of the cause and location of a possible obstruction. In the first 12-18 months sonography allows evaluation of the lateral ventricles and the third ventricle and CT is usually only chosen in children in emergency situations and/or if no other modality is available.

PERFORMANCE

We retrospectively evaluated a population of 785 children and adolescents (426 males aged 0-17 years) referred for MRI between April 2009 and March 2012 due to headaches, somnolence, concentration difficulties or developmental delay. Among these 80 (49 male) met the MRI criteria for hydrocephalus, 75 (46 male) had non-communicating hydrocephalus and 5 (3 male) communicating hydrocephalus. Of the patients 24 (15 male) had posthemorrhagic aqueductal stenosis, 16 (8 male) intracranial tumors, 9 (6 male) Chiari II malformations, 5 (4 male) other congenital malformations including malformations of the Dandy Walker spectrum, 9 (3 male) idiopathic aqueductal stenosis, 7 (5 male) arachnoidal cysts and 10 (8 male) other disorders, such as post-infections, macrocephaly cutis marmorata telangiectatica congenita (M-CMTC) syndrome, mesencephalic arteriovenous malformation (AVM), Langerhans cell histiocystosis.

PRACTICAL RECOMMENDATIONS

It is important to take the age of the patient and the imaging pattern into account and to exclude tumors when reporting MR images of children with hydrocephalus.

Microsurgical outlet restoration in isolated fourth ventricular hydrocephalus: a single-institutional experience

PURPOSE

Isolated fourth ventricles as a consequence of shunted posthemorrhagic hydrocephalus can cause significant brainstem compression and subsequent clinical deficits in children. Several treatment options have been described. We report the clinical and radiological outcome after microsurgical fenestration of fourth ventricular outlet foramen via a suboccipital approach.

METHODS

In nine patients (age, 9 to 87 months; median age, 21 months), microsurgical reopening of formerly occluded outlet foramen of the fourth ventricle was performed under electrophysiological monitoring. Pre- and postoperative clinical outcome as well as radiological results are reported.

RESULTS

Mean follow-up for all children was 25 months. Three children older than 3 years were less significantly involved, the remaining six showed tremendous long tract signs and lower cranial nerve deficits. All children exhibited a remarkable improvement of their preexisting neurological deficits post-surgery. Despite successful fenestration, one child required additional internal drainage of fourth ventricle to the lateral ventricles due to malabsorption. Median diameters of the fourth ventricle changed markedly after surgery with anterior-posterior (a.p.) extension from 3.8 to 2.9 cm, lateral extension from 4.2 to 2.8 cm (p = 0.018), and craniocaudal extension from 5.8 to 4.7 cm, respectively. Also, the pontine a.p. diameter increased significantly from 0.8 to 1.5 cm (p = 0.022).

CONCLUSION

The clinical and radiological outcomes after microsurgical fenestration in children with an isolated fourth ventricle are very promising. This treatment modality is a safe and effective shunt-free option when electrophysiological monitoring and thorough preoperative neuroradiological work-up are applied.

Intramedullary pilomyxoid astrocytoma with intracerebral metastasis exhibiting oligoden-droglioma-like features

Intramedullary glioma are rare and their biological behaviour can differ from their cerebral counterparts. Pilomyxoid astrocytoma (PMA, WHO grade II), predominantly occur in the hypothalamic/chiasmatic region of infants and children. The few reported cases of pediatric intramedullary PMA displayed a particularly aggressive behavior. Here, we report a diagnostically challenging case of a five year old female patient presenting with intramedullary glioma and local tumor recurrence three years later. Twelve years after the initial manifestation, a second tumor was found intracerebrally. We performed a comprehensive histological, molecular pathological and imaging analysis of the tumors from both localizations. The results revealed a metastasizing PMA with unique histological and genetic features. Our study indicates that PMA comprise a heterogeneous group including aggressive subtypes which may not be compatible with the current classification according to WHO grade II. Furthermore, the case emphasizes the increasing relevance of molecular pathological markers complementing classic histo-logical diagnosis.

Proper cerebellar development requires expression of β1-integrin in Bergmann glia, but not in granule neurons

β1-class integrins play essential roles both in developmental biology as well as in cancer. Particularly, a Nestin-driven deletion of β1-integrin receptors results in severe abnormalities of brain development including a laminar disorganization of cerebellar granule neurons. However, since Nestin is expressed in all kinds of neural precursors, these data do not allow conclusions to be drawn about the role of β1-integrins in distinct neuronal and glial cell types. By generating conditional knockout mice using granule cell-specific Math1-promoter sequences, we show here that the expression of β1-integrins in granule neurons is dispensable for the development of the cerebellum. Also, deletion of β1-integrin from tumors that arise in a mouse model of granule cell precursor-derived medulloblastoma did not result in a significant survival benefit. Last, expression levels of β1-integrin in human medulloblastoma samples did not predict patient's outcome. However, a β1-integrin knockout using hGFAP-promoter sequences led to cerebellar hypoplasia, inappropriate positioning of Bergmann glia cells in the molecular layer, undirected outgrowth of radial glia fibers, and granule cell ectopia. We therefore conclude that β1-integrin expression in cerebellar granule neurons is not essential during normal development or medulloblastoma formation. In fact, it is the expression of β1-integrin in glia that is crucial for the proper development of the cerebellar cortex.

Congruence and discrepancy of interictal and ictal EEG with MRI lesions in focal epilepsies

OBJECTIVE

To compare the occurrence and localization of interictal epileptiform discharges (IEDs) and epileptic seizure patterns (ESPs) with the localization of MRI lesions.

METHODS

We retrospectively analyzed the EEG and MRI data of a series of patients with focal epilepsies that had been studied from 1991 to 2009.

RESULTS

In patients with temporal lesions, the localization of IEDs was most congruent (58.6% with IEDs exclusively over the lesional lobe and 29.7% with a majority of temporal IEDs). This differed (p < 0.001) from frontal lesions (27.5% with exclusively frontal IEDs, 24.6% with a majority of frontal IEDs). In parieto-occipital lobe lesions, only 12.1% had IEDs exclusively over the lesional lobe compared to 48.5% with no parieto-occipital IEDs at all. Patients with central lesions often lacked any IEDs (54.5%, p < 0.001). The occurrence and localization of ESPs also differed between the regions. They were most congruent in temporal lesions (63.5% of patient had ESPs only over the lesional lobe, 23.4% had the majority of ESPs over the lesional lobe), which differed from frontal and parieto-occipital lesions (37.7% and 30.3% of patients with ESPs only over the lesional lobe). Patients with central lesions had ESPs very frequently only outside the lesional lobe (63.6%). Surgery outcome did not differ between the regions.

CONCLUSIONS

The occurrence and localization of interictal and ictal EEG findings differs vastly for lesions in different brain regions. These findings should be used to carefully weigh the results from EEG studies particularly in patients with extratemporal epilepsies considered for epilepsy surgery.

IDH1 mutations in grade II astrocytomas are associated with unfavorable progression-free survival and prolonged postrecurrence survival

BACKGROUND

The favorable prognostic impact of mutations in the IDH1 gene is well documented for malignant gliomas; its influence on World Health Organization (WHO) grade II astrocytomas, however, is still under debate.

METHODS

A previously published database of 127 predominantly surgically treated patients harboring WHO grade II astrocytomas was revisited. Patients were screened for TP53 mutations (sequencing analysis), IDH1 mutations (pyrosequencing), and MGMT promoter methylation (methylation-specific polymerase chain reaction and bisulfite sequencing). Endpoints were overall survival, progression-free survival (PFS), time to malignant transformation, and postrecurrence survival. Radiotherapy was usually withheld until tumor progression/malignant transformation occurred.

RESULTS

IDH1 mutations, TP53 mutations, and methylated MGMT promoters were seen in 78.1%, 51.2%, and 80.0% of the analyzed tumors, respectively. IDH1 mutations, which were significantly associated with TP53 mutations and/or MGMT promoter methylation (P < .001), resulted in shortened PFS (median, 47 vs 84 months; P = .004); postrecurrence survival, however, was significantly increased in those patients undergoing malignant transformation (median, 49 vs 13.5 months; P = .006). Overall survival was not affected by IDH1. A similar pattern of influence was seen for MGMT promoter methylation. Methylated tumors did significantly worse (better) in terms of PFS (postrecurrence survival); a low number of unmethylated tumors, however, limited the power of this analysis. Conversely, TP53 mutations were stringently associated with a worse prognosis throughout the course of the disease.

CONCLUSIONS

IDH1 mutations are associated with a Janus headlike phenomenon; unfavorable prognostic influence on PFS turns into favorable impact on postrecurrence survival. A similar pattern of influence might exist for MGMT methylation.

Children with tethered cord syndrome of different etiology benefit from microsurgery-a single institution experience

PURPOSE

The term "tethered cord syndrome" (TCS) illustrates, according to the literature, both a separate diagnosis, as well as a combination of symptoms in the context of dysraphic conditions. The common denominator is the increased tension and abnormal stretching of the spinal cord, caused by tissue attachments that limit its movement in the spinal canal. In light of the fact that no real data exists regarding the management of these patients, the purpose of this single institutional study is to underscore management strategies and discuss the results, pitfalls, and the treatment of pediatric patients with tethered cord syndrome.

METHODS AND RESULTS

The clinical outcome in 20 pediatric patients was studied retrospectively. Ten children with closed spinal dysraphism, nine with tethering after postpartum myelomeningocele repair, and one child with an infected open dermal sinus were included. A total of 22 detethering procedures were performed. The most common symptoms prior to surgery were muscle weakness and urinary dysfunction, followed by foot deformities and pain. Of all symptoms, pain responded most favorably to surgical treatment. There was improvement in 11 out of 15 patients with preoperative motor deficits, while that was the case in 11 out of 16 patients with urinary dysfunction.

CONCLUSIONS

In view of the lack of evidence regarding the treatment of children with tethered cord syndrome, the best way to aim for a favorable outcome is correct indication for surgical intervention, combined with the implementation of technical advancements, such as intraoperative neurophysiological monitoring and ultrasound.

Haemophilus paraphrophilus, a rare cause of intracerebral abscess in children

We report on a 3-year-old boy presenting with left-sided eyelid myocloni due to an intracranial abscess harboring Haemophilus paraphrophilus. This is the first description of an intracranial infection with this pathogen in a child.

Ictal SPECT in Sturge-Weber syndrome

We report on a patient with right-sided Sturge-Weber syndrome (SWS), in whom earlier functional hemispherectomy failed. Subtraction of ictal and interictal single-photon-emission-computed-tomography (SPECT) superimposed on individual MRI showed a right fronto-orbital hyperperfusion, with a left-sided EEG seizure pattern. Ictal SPECT supported our assumption that right frontal originated seizure pattern propagated to left hemisphere via the remaining right frontal bridge. Right orbito-frontal resection and disconnection from corpus callosum resulted in seizure freedom.

Reversible dementia and corresponding CSF alterations due to intraspinal lumbosacral metastasis of a prostate carcinoma

We report, for the first time, how intraspinal carcinoma metastasis can cause reversible dementia accompanied by distinct cerebrospinal fluid (CSF) alterations. A 73-year-old male patient who suffered from rapidly progressive dementia and gait disturbance showed marked abnormalities of CSF tau protein, amyloid beta(1-42), and prostate-specific antigen. A lumbosacral, intraspinal metastasis from a prostate carcinoma was found, and after microsurgical removal, CSF alterations normalized and the clinical symptoms regressed. This case illustrates how malignant tumors can disturb brain function via indirect mechanisms.

Interstitial iodine-125 radiosurgery alone or in combination with microsurgery for pediatric patients with eloquently located low-grade glioma: a pilot study

PURPOSE

The optimal therapeutic management of children with World Health Organization grade I and II gliomas not accessible to complete resection is poorly defined. Radical surgical resection is the first-line treatment for large hemispheric tumors, whereas interstitial iodine-125 radiosurgery (IRS) might be an attractive treatment concept for selected patients with small (tumor diameter in the range of 4 cm) and circumscribed tumors in any location of the brain. Precise high-dose application, maximal sparing of surrounding normal tissue, and the absence of long-term complications have been reported to be the hallmark of IRS. Therefore, the therapeutic impact and the risk of IRS alone or in combination with microsurgery (in case of larger tumor volumes) were prospectively examined.

METHODS

Seven boys and four girls were included (mean age, 6.8 years; range, 11 months to 16 years). IRS (after stereotactic biopsy) was considered to be indicated for circumscribed tumors with a diameter in the range of 4 cm (four cases). For larger tumors, a combined microsurgical/radiosurgical approach was preferred (seven patients). Temporary iodine-125 seeds were used exclusively (tumor dose calculated to the boundary, 54 Gy; dose rate, 10 cGy/h). Tumor location was hypothalamic/suprasellar in four, lobar in three, deep (thalamus and pineal gland) in two, and within the brain stem in two children. Treatment effects of IRS were estimated according to the MacDonald criteria.

RESULTS

A complete response after IRS was seen in four patients, and a partial response was seen in seven patients (median follow-up, 31.5 months). There was no perioperative morbidity after microsurgery and/or IRS, and no radiogenic complications occurred during the follow-up period. Five patients experienced an improvement in their deficits, and no deterioration in neurological/endocrine function was seen in any of the patients at the time of last follow-up evaluation.

CONCLUSION

IRS alone or in combination with microsurgery (in the case of larger tumors) is a safe, effective, and minimally invasive treatment strategy for eloquently located pediatric low-grade gliomas and deserves further prospective evaluation.

Analysis of mammalian septin expression in human malignant brain tumors

Septins are a highly conserved subfamily of GTPases that play an important role in the process of cytokinesis. To increase our understanding of the expression and localization of the different mammalian septins in human brain tumors, we used antibodies against septins 2, 3, 4, 5, 6, 7, 9, and 11 in immunofluorescence and Western blot analyses of astrocytomas and medulloblastomas. We then characterized the expression and subcellular distribution of the SEPT2 protein in aphidicolin-synchronized U373 MG astrocytoma cells by immunofluorescence and fluorescence-activated cell sorter analysis. To determine the role of SEPT2 in astrocytoma cytokinesis, we inducibly expressed a dominant-negative (DN) SEPT2 mutant in U373 MG astrocytoma cells. We show variable levels and expression patterns of the different septins in brain tissue, brain tumor specimens, and human brain tumor cell lines. SEPT2 was abundantly expressed in all brain tumor samples and cell lines studied. SEPT3 was expressed in medulloblastoma specimens and cell lines, but not in astrocytoma specimens or cell lines. SEPT2 expression was cell cycle-related, with maximal levels in G2-M. Immunocytochemical analysis showed endogenous levels of the different septins within the perinuclear and peripheral cytoplasmic regions. In mitosis, SEPT2 was concentrated at the cleavage furrow. By immunocytochemistry and flow cytometry, we show that a DN SEPT2 mutant inhibits the completion of cell division and results in the accumulation of multinucleated cells. These results suggest that septins are variably expressed in human brain tumors. Stable expression of the DN SEPT2 mutant leads to a G2-M cell cycle block in astrocytoma cells.

Inducible expression of p57KIP2 inhibits glioma cell motility and invasion

To examine the role of p57KIP2 in human malignant glioma cells, we studied its expression in a panel of human malignant glioma specimens by western blot and immunohistochemical analysis. To determine the effects of p57KIP2 expression on the phenotype of glioma cells, we analyzed two inducible stably transfected p57KIP2 expressing glioma cell lines. Expression of p57KIP2 was induced in U373 and U87 malignant glioma cells with doxycycline using the tetracycline repressor system. A phagokinetic track assay on gold particles was used to investigate differences in cell migration between p57KIP2 expressing and non-expressing control cells. The effects of the extracellular matrix (ECM) on U373 motility was determined in p57+ and p57-cells on surfaces coated with 5 microg/cm2 of fibronectin, laminin, type I and type IV collagens. The invasion of p57+ and p57- glioma cells across BD Biocoat Matrigel invasion chambers was then determined. p57KIP2 was weakly expressed in 4/6 glioblastoma (GBM) specimens by western blot. By immunohistochemistry, p57KIP2 immunoreactivity was positive in 8/40 GBMs, and was primarily nuclear in location. The motility of U373 glioma cells was significantly reduced after p57KIP2 induction. The presence of ECM proteins did not further alter the motility of p57+ and p57- glioma cells. The results of the invasion chamber assay showed that p57+ cells exhibited a 35% reduction in their invasive capacity as compared to p57- cells. These data suggest that p57KIP2 is expressed in at least some malignant gliomas. Inducible expression of 57KIP2 in cell lines deficient in this cyclin-dependent kinase inhibitor reduces their otility and invasiveness.

Prognostic impact ofTP53 mutation status for adult patients with supratentorial World Health Organization Grade II astrocytoma or oligoastrocytoma

BACKGROUND

The goal of the current study was to retrospectively assess the prognostic impact of TP53 mutation status and P53 expression/accumulation on long-term outcome for adult patients with supratentorial World Health Organization (WHO) Grade II astrocytoma or oligoastrocytoma.

METHODS

The authors revisited a previously published short-term data set containing information on 159 consecutive patients who were treated between 1991 and 1998. Each patient was screened for TP53 mutations and P53 overexpression/accumulation. The reference point for all analyses was the date of surgical treatment, and the date of last follow-up examination was August 2002. Overall survival, progression-free survival, postrecurrence survival, and time to malignant transformation were estimated using the Kaplan-Meier method, and potential prognostic factors were evaluated using the multivariate proportional hazards model.

RESULTS

The median follow-up duration for survivors was 80.4 months (standard deviation, 33.0 months). TP53 mutations, which were present in 49.1% of all tumors, occurred preferentially in gemistocytic tumors (P < 0.05). In addition, the TP53 status of the primary tumor was predictive of the TP53 status of the recurrent tumor in all cases of disease recurrence. The 5-year overall and progression-free survival rates were 77.5% and 43.2%, respectively, and the risk of malignant transformation at 5 years postsurgery was 32.7%. Unfavorable prognostic factors with respect to survival duration included older age (> or = 50 years; P < 0.002), gemistocytic subtype (P < 0.01), and positive TP53 mutation status (P < 0.05), all of which were also negatively associated with progression-free survival (P < 0.05, P < 0.001, and P < 0.003, respectively). In contrast, positive TP53 mutation status was the only significant predictor of a reduction in time to malignant transformation (P < 0.03). P53 overexpression/accumulation did not exhibit prognostic relevance in any of the multivariate models constructed in the current study.

CONCLUSIONS

TP53 mutations are common early events in the pathogenesis of WHO Grade II astrocytoma or oligoastrocytoma. In the current study, positive TP53 mutation status (but not P53 overexpression/accumulation) was found to be an independent unfavorable predictor of survival, progression-free survival, and time to malignant transformation. The therapeutic implications of these findings have yet to be determined.

Fatal ethibloc embolization of vertebrobasilar system following percutaneous injection into aneurysmal bone cyst of the second cervical vertebra

A 4-year-old boy developed progressive neck pain and an expansile osteogenic lesion of C2; the diagnosis was an aneurysmal bone cyst. An image-guided biopsy with 3D CT planning was performed followed by Ethibloc injection into the aneurysmal bone cyst. Subsequent CT and MR images demonstrated embolization material in the vertebrobasilar system, and the patient died of brain stem and cerebellar infarction 23 hours after the intervention. The course of events and technical considerations are discussed.

Expression of fascin, an actin-bundling protein, in astrocytomas of varying grades

Malignant astrocytomas are highly infiltrative neoplasms that invade readily into regions of normal brain. On a cellular basis, the motility and invasiveness of human cancers can be ascribed in part to complex rearrangements of the actin cytoskeleton that are governed by several actinbinding proteins. One such actin-binding protein that has been linked to the invasive behavior of carcinomas is fascin, which serves to aggregate F actin into bundles. In this study, we examined the expression of fascin in a series of human malignant astrocytomas (WHO grades I-IV). Five grade I, 5 grade II, 10 grade III, and 26 grade IV human astrocytomas were examined for fascin and glial fibrillary acidic protein (GFAP) expression by double immunofluorescence confocal microscopy. Expression of fascin and GFAP was also determined by Western blot analysis. Fascin expression increased with increasing WHO grade of astrocytoma. This is in marked contrast to GFAP expression, which decreased with increasing WHO grade. In grades I and II neoplasms, and within non-neoplastic brain, fascin and GFAP were expressed diffusely within regions examined. However, in the higher-grade astrocytomas (grades III and IV), fascin and GFAP were expressed regionally in distinctly separate tumor cell populations. This is the first study to demonstrate the expression of fascin in human astrocytic neoplasms. The role that fascin plays in contributing to the invasive phenotype of anaplastic astrocytomas awaits further study and investigation.