Recurrent cerebellar liponeurocytoma with anaplastic features at initial presentation: A case report.

BACKGROUND: Cerebellar liponeurocytoma is a rare entity with fewer than 100 reported cases and series in the available literature to date. Although the cerebellum remains the typical primary site, the entity has been shown to demonstrate increased aggressiveness and malignant progression with multiple recurrences. CASE DESCRIPTION: We present a unique case in a 64-year-old gentleman of a cerebellar liponeurocytoma with multiple recurrences and progressive anaplasia. The tumor showed anaplastic features at first presentation and recurred in a more aggressive fashion in a short 2-year period despite surgical debulking and post-operative radiotherapy. It re-recurred within 6 months with subsequent re-debulking without further radiotherapy. At latest follow-up almost 3 years since surgical management of the patient's second recurrence, the patient remains well with minimal neurological impairment and no radiological signs of recurrence. CONCLUSION: Cerebellar liponeurocytoma may present with increasingly atypical histological features that may warrant more aggressive post-operative treatment to prevent disease recurrence and clinical deterioration. This may include a more aggressive surgical resection margin and consideration of adjuvant radiotherapy in all cases.

MRI features of an atypical case of extraventricular neurocytoma: A case report.

RATIONALE: Central neurocytoma occurring outside the ventricles is known as extraventricular neurocytoma (EVN). EVN is rare and its magnetic resonance imaging (MRI) findings vary greatly and overlap with the imaging features of other intracerebral primary tumors. PATIENT CONCERNS: A 21-year-old woman with an intrauterine pregnancy of 18+2 weeks complained of dizziness and headache for 3 months. DIAGNOSIS: A 8.6 cm × 5.8 cm × 3.7 cm space-occupying lesion was seen in the right frontal lobe on MRI, with mixed long signals on T1-weighted imaging and mixed slightly long signals on T2-weighted imaging, slightly hyperintense on T2-weighted imaging fluid attenuated inversion recovery images, and a large-scope long T1-weighted imaging and long T2-weighted imaging cystic component at the center of the lesion. A thick fence-like enhancement of the solid component at the periphery of the lesion was observed after injecting a contrast medium, while the internal cystic component was not enhanced. The MRI diagnosis was of glioma. The lesion was pathologically confirmed as an atypical central neurocytoma of the right frontal lobe. INTERVENTIONS: Resection of the lesion and postoperative radiotherapy. OUTCOMES: The patient was lost to follow-up. LESSONS: EVN can be considered as a differential diagnosis for lesions occurring in the cerebral hemispheres of young patients with cystic degeneration, thick fence-like enhancement, and peritumoral edema on MRI.

Extraventricular neurocytomas: a systematic review of the literature in the pediatric population.

Extraventricular neurocytomas (EVNs) are rare neuroepithelial neoplasms of the central nervous system that were first described in 1997. Most studies in patients with EVNs have incorporated mixed age groups. The tumor's clinical behavior specifically in children has not been explored in depth, while a detailed statistical analysis has never been performed in this age group. Hence, we performed a systematic review to address possible prognostic factors and the appropriate management in children with EVNs. Relevant studies were identified by searching the MEDLINE and SCOPUS databases. We included studies concerning patients 18 years of age or younger who were histologically diagnosed with EVNs. A total of 52 studies with 79 patients were included. The mean age of the patients was ~ 10 years with a male predilection (~ 2:1). Most of these tumors were located in the frontal (49%) lobe. We observed that gross total resection of the tumor was significantly lower in cases of atypical EVNs (p < 0.05). Additionally, atypical EVNs were associated with worse overall survival compared to typical EVNs (p = 0.05). Children 4 years of age or under had a worst outcome (p = 0.001). The patient's sex and the extent of the tumor's resection did not appear to affect the prognosis in a statistically significant manner. Contrary to the results of previous studies, the use of adjuvant radiotherapy or chemotherapy for the treatment of EVNs was not associated with better outcomes in the pediatric population. Thus, a less aggressive management of children with EVNs compared to the adult population is suggested.

Atypical central neurocytoma with leptomeningeal dissemination: a case report.

BACKGROUND: Central neurocytomas represent 0.25-0.5% of all intracranial tumors in adults. Leptomeningeal spread is uncommon, and the exact incidence of meningeal spread is unknown due to sparse literature. We present the clinical course and management outcome of a case of atypical central neurocytoma with leptomeningeal spread. CASE PRESENTATION: A young gentleman, who initially presented with memory loss, was found to have a right intra-axial periventricular mass on imaging. He underwent subtotal resection, and operative histopathology suggested a periventricular atypical neurocytoma. In view of subtotal resection, adjuvant focal radiation therapy was recommended, but he developed headache and blurring of vision 10 days postoperatively. Contrast enhanced craniospinal magnetic resonance imaging (MRI) showed residual primary tumor as well as diffuse leptomeningeal spread. Cerebrospinal fluid cytology also showed malignant cells. After tumor board discussion, craniospinal axis irradiation was advised and delivered. He remained disease-free for 10 months after radiation therapy, but then developed local and spinal recurrence, and offered salvage chemotherapy. His general condition deteriorated following chemotherapy with disease progression, and he was subsequently advised best supportive care. CONCLUSION: Leptomeningeal dissemination in atypical neurocytomas portends an aggressive course and adverse prognosis; management decisions may need tailoring as per individual presentation.

Central Neurocytoma Treatment Modalities: A Systematic Review Assessing the Outcomes of Combined Maximal Safe Resection and Radiotherapy with Gross Total Resection.

BACKGROUND: Central neurocytomas (CNCs) are rare intraventricular lesions comprising <1% of primary brain tumors. Their surgical and adjuvant management is unclear. OBJECTIVE: Our goal was to update Rades et al.'s 2006 systematic review to assess the outcome differences among 3 fundamental therapies for CNC: gross total resection with and without radiation therapy (RT) versus maximal safe resection with adjuvant RT. METHODS: Articles indexed on PubMed and Google Scholar and published between January 1, 2006 and December 31, 2019 were selected using the PRISMA criteria. Studies were excluded if they had fewer than 3 cases, did not categorize extent of resection, or were duplicate studies, technical reports, case reports, or studies without follow-up. Complication rates, recurrence rates, overall survival and progression-free survival were extracted where possible. χ2 proportionality tests were used for comparison (P values >0.05 suggested significance). RESULTS: On aggregation, 615 patients from 13 studies including ours were assessed. Although overall survival was not significantly different (χ2 = 1.56; P = 0.46), the recurrence rate differed significantly between GTR + RT (6.9%, 92.11 months), GTR-RT (23.9%, 96.8 months), and MSR + RT (16.8%, 85 months) (χ2 = 10.94; P = 0.004). Pooled complication rates for GTR and MSR + RT were 31.2% and 24% (P = 0.049), respectively. CONCLUSIONS: RT remains an important adjuvant treatment that can improve patient survival in the presence of MSR to levels comparable to those of GTR or GTR + RT. Where total resection carries too much risk, MSR + RT can be considered as the next best alternative for tumor control.

Radiation-Induced Brain Aneurysms: Institutional Experience and State of the Art in the Contemporary Literature.

BACKGROUND: Brain aneurysms (BAs) are the most common intracranial vascular condition, with an overall incidence of 1%-2%. Among the common causes of their initial formation and growth, the role of radiation therapy (RT) has been reported in some studies. The aim of the present study is to report the most relevant features of BA related to a previous cranial RT. METHODS: Data deriving from 1 patient treated for RT-induced BA in our institution were added to reports of another 66 BAs retrieved from the literature. The following parameters were evaluated: age, sex, location, primary lesion, clinical presentation, dosage/amount of radiation delivered, type of treatment for the BA, dimension, morphology, chemotherapy, comorbidities, risk factors, and number of BAs. RESULTS: The most commonly involved vessel was the internal carotid artery (34%). In general, the anterior circulation showed higher vulnerability compared with the posterior circulation and middle cerebral artery (56.7%). The average latency between RT and the first imaging showing the BA was 9.01 ± 6.85 years. Vessels coursing in the posterior cranial fossa showed a significant univariate association with lower X-ray dosages (P = 0.014) compared with the other locations. No statistically significant correlation between the continuous variables age, latency of BA appearance, RT delivered dose, and dimension of the BA was shown. CONCLUSIONS: The apparent higher fragility of the vascular structures of the posterior cranial fossa was statistically outlined, and the X-ray dosage, the primary condition target of the RT, the age of the patients, and no statistically significant correlation were outlined. Biological factors could play a significant role.

Complete resection of hypervascularised extraventricular neurocytoma after preoperative embolisation. / Resección completa de neurocitoma extraventricular hipervascularizado tras embolización preoperatoria.

A 13-year-old female arrived at the Emergency Department with a two-week history of headache, and bilateral papilloedema on examination. The initial study with CT and MRI showed a large multicystic left frontal mass with calcification surrounded by peripheral oedema, subacute intralesional bleeding and association of multiple large vessels. She was initially operated on in another centre where a subacute haematoma was found, evacuating to multiple vessels and arteriolised veins. Despite the earlier neuroimaging findings, arteriovenous malformation (AVM) was suspected, so she was referred to our centre for further treatment. We performed angiography, MR angiography and MRI with advanced sequences, diagnosing a highly vascularised intra-axial tumour which was embolised. The patient was then definitively operated on, with the resulting finding of extraventricular neurocytoma (EVN). EVN are extremely rare lesions, not previously described in the literature as hypervascularised lesions, which in our case required prior angiography and embolisation for proper diagnosis and adequate management.

Prognosis and treatment outcomes of central neurocytomas: clinical interrogation based on a single center experience.

INTRODUCTION: Central neurocytoma (CN) is a very rare neuronal neoplasm. The clinical implications of the potential prognostic factors for these lesions, including tumor atypia, have therefore not been clarified. METHODS: Forty CN patients were enrolled and reclassified as typical or atypical in accordance with an MIB-1 labeling index (LI) of above and below 2%. RESULTS: We classified our retrospective study cohort as 21 (52.5%) typical and 19 (47.5%) atypical CN cases. No significant differences were found in terms of sex, mean age, mean tumor size or tumor location between these groups. Recurrences occurred in 2 (9.5%) typical and 6 (33.3%) atypical cases. The typical CN 2-,3- and 5-year PFS rates were 100%, 100%, 92.3%, and those for the atypical group were 93.8%, 78.1%, 65.1%, respectively (p = 0.02). The PFS rates did not statistically differ by treatment modality (gross total resection alone, subtotal resection (STR) alone and STR plus radiation therapy (RT) or radiosurgery (RS)) either in the whole cohort (p = 0.75) or in the typical CN and atypical CN subgroups (p = 0.45 and 0.98, respectively). An atypical histology was the only prognostic indicator of recurrence by univariate analysis (hazard ratio: 5.40, p = 0.04). CONCLUSIONS: An atypical lesion (MIB-LI > 2%) is an important prognostic indicator in CN. The clinical implications of the extent of resection for CN patients are still debatable. The use of STR plus RT or RS may be a viable treatment strategy for CN but different therapeutic and follow-up approaches for atypical CN will be needed.

Cerebellar Liponeurocytoma: The Dilemma of Multifocality.

BACKGROUND: Cerebellar liponeurocytoma (cLNC) is a rare benign glioneuronal tumor with only ~60 cases reported since its first description in 1978. They have occurred largely as sporadic cases; however, familial cases with possible autosomal dominant inheritance have also been reported. Surgical excision has been considered the main modality of treatment, even for recurrent lesions. Uncertainties exist regarding the natural history, long-term outcomes, and optimal postoperative management and follow-up protocols for cLNC in general and multifocal cLNC in particular. Multifocality is exceedingly rare, with only 4 cases reported previously. CASE DESCRIPTION: We present a case of multifocal cLNC in a young woman who had presented with progressive cerebellar symptoms of 5 months' duration. Her diagnostic neuroimaging evaluations revealed 2 asymmetric mass lesions (1 on each cerebellar hemisphere). We excised the larger lesion to relieve the mass effect and decided to monitor the smaller lesion radiologically. However, she developed a new lesion during the follow-up period and required adjuvant radiotherapy. CONCLUSION: Surgical excision forms the cornerstone of management of cLNCs. However, it is necessary to vigilantly monitor these patients owing to the high recurrence rates of cLNC despite the innocuous histologic features.

The role of proton beam therapy in central neurocytoma: A single-institution experience.

PURPOSE: Central neurocytomas (CNs) are rare World Health Organization grade II tumors managed with surgery and radiation therapy. We report our experience in managing CN with proton beam therapy (PBT) when radiation therapy was used. METHODS AND MATERIALS: We identified 61 patients with pathologically diagnosed CN treated at our institution between 1996 and 2016, of which 24 met inclusion criteria. Patient, tumor, and treatment characteristics are reported in context of progression-free survival and treatment-related adverse events. RESULTS: Of 24 patients identified, median age at diagnosis was 21 years (range, 14-60). Median maximal tumor diameter was 4.5 cm (range, 1.4-6.8). Eighteen (75%) patients underwent upfront surgery alone. Sixteen (67%) patients received adjuvant or salvage PBT at a median dose of 54 Gy (relative biological effectiveness). Median follow-up was 56 months. Median progression-free survival (PFS) was 61 months. Eleven patients had disease progression with median time to progression of 22 months. Of the 5 patients with gross total resection, 4 experienced local recurrence and had MIB-1 >4% (range, 4.5-30). There was improved PFS with addition of PBT to definitive surgery (log-rank, P = .06); there was no disease progression to date. In patients who experienced disease recurrence/progression, MIB-1 <4% was associated with improved PFS (log-rank, P = .007). All patients tolerated PBT well with toxicities typical for cranial irradiation and with no grade 3+ toxicities. CONCLUSION: In our cohort, CN with elevated MIB-1 index were at increased risk for disease progression. However, adjuvant radiation therapy appears to effectively prevent failure. PBT toxicities appear to be comparable to if not less than published photon experiences.

Central neurocytoma: Clinical characteristics, patterns of care, and survival.

PURPOSE: To investigate clinical characteristics and patterns of care among patients with central neurocytomas in a large cohort of patients. METHODS: The National Cancer Database (NCDB) was queried to identify patients with biopsy confirmed neurocytoma from 2004 to 2015. Patterns of care were described and univariable and multivariable models were performed to investigate the impact of prognostic factors on overall survival. RESULTS: Among 223,404 patients with brain tumors in the NCDB, 868 patients were diagnosed with biopsy-proven neurocytoma and analyzed (0.4% or approximately 75 patients annually). Median age at diagnosis was 31 years and median tumor size was 4-5 cm. Diagnosis was similar between male (49.5%) and female (50.5%). Regarding location, 622 (72%) tumors were intraventricular, 168 (19%) were extra-ventricular, and 78 (9%) overlapping or unspecified. Five-year overall survival among all patients was 89%. On multivariable analysis tumor location, extent of resection, and use of radiation, were not predictive for improved survival (each p > 0.05); however, patient age (p < 0.001), WHO grade (p < 0.001), and medical comorbidity scores (p = 0.002) were independently associated with overall survival. CONCLUSION: Patients with central neurocytoma often present as young adults with sizable tumor burden and are well managed with surgery alone. Considering their favorable survival, efforts to improve tumor control should be carefully weighed against the long-term risks associated with adjuvant therapy like radiation.

Patterns of care and survival outcomes in patients with an extraventricular neurocytoma: An individual patient data analysis of 201 cases.

INTRODUCTION:: Extraventricular neurocytoma is a rare neuronal tumor arising outside the ventricles. However, because of its rarity, its optimum treatment remains undefined. MATERIALS AND METHODS: We intended to perform an individual patient data analysis to examine the patterns of care and prognostic factors involved in the treatment of extraventricular neurocytomas. PubMed, SCOPUS, and Google Scholar were searched with the following MeSH terms: "Neurocytoma, Extra ventricular neurocytoma, Spinal neurocytoma AND treatment, Survival" to find all possible publications pertaining to EVN. RESULTS: From 108 publications, we retrieved 201 patients of extraventricular neurocytoma. Their median age was 30 years (range: 0.6-78 years). Sixty seven patients were in the pediatric (age ≤20 years) age group. There was a bimodal age distribution. Surgical details were available for 132 cases, and 51.5% underwent a gross total resection whereas 41.7% underwent a subtotal resection. Adjuvant radiation was used in 40% cases. For the entire cohort, the median progression free survival was 77 months (53.3-100.7). However, we could not find an impact of any of the prognostic factors on survival. CONCLUSION: An extraventricular neurocytoma is a very rare disease with varied presentations and different sites of origin. Gross total resection remains the standard of care. Adjuvant radiation may be used for salvage. However, radiation therapy after subtotal resection of an atypical neurocytoma may be administered.

Clinical, radiological, pathological and prognostic aspects of intraventricular oligodendroglioma: comparison with central neurocytoma.

Studies comparing intraventricular oligodendroglioma (IVO) and central neurocytoma (CN) in terms of their clinical, radiological and pathological features are scarce. We, therefore, investigated the similarities and differences between these types of tumors to get a better understanding of how they may be more properly diagnosed and treated. The clinical manifestations, CT/MRI findings, pathological characteristics and clinical outcomes of 8 cases of IVOs and 12 cases of CNs were analyzed retrospectively. Both IVO and CN occurred most commonly in young adults and manifested with symptoms of increased intracranial pressure secondary to obstructive hydrocephalus. However, they were radiologically different in location (p = 0.007), diffusion-weighted imaging (p = 0.001), "scalloping" appearance (p = 0.006), flow void sign (p = 0.006) and ventricular wall invasion (p = 0.000). Histologically, significant differences in mitotic count (p = 0.008) and parenchymal infiltration (p = 0.01) were noted. Immunohistochemically, significant differences in the expression of Olig2 (p = 0.000), Syn (p = 0.01) and NeuN (p = 0.000) were observed. In addition, MIB-1 labeling index (p = 0.035) and case fatality rate (p = 0.021) of IVO were much higher than those of CN, while survival rate of IVO was much lower than that of CN (p = 0.028). IVO and CN are similar in onset age and clinical manifestations, but have different imaging and pathological features. Patients with IVOs may have a relatively poorer prognosis compared to those with CNs.

Pediatric Basal Ganglia Region Tumors: Clinical and Radiologic Features Correlated with Histopathologic Findings.

PURPOSE: To summarize the clinical and radiologic features of pediatric basal ganglia region tumors (PBGRT) in correlation with their histopathologic findings to reduce inappropriate surgery and identify tumors that can benefit from maximal safe resection. METHODS: The records of 35 children with PBGRT treated in our hospital from December 2011 to December 2015 were analyzed retrospectively. The clinical and radiologic features of these tumors were summarized and correlated with their histopathologic diagnosis. RESULTS: Our series included 15 astrocytomas and 11 germ cell tumors (GCTs). Basal ganglia astrocytomas were characterized by various clinical presentations and an ill-circumscribed mass with the involvement of surrounding structures on neuroimaging and mostly occurred in the first decade of life (n = 10; 66.7%). Basal ganglia GCT mostly occurred in the second decade of life (n = 8; 72.7%) with hemiparesis as the most common symptom (n = 9; 81.8%). The tumors were located predominantly in the caput of caudate nucleus (n = 8; 72.7%) with hemiatrophy as the typical sign (n = 8; 72.7%). Occasionally, other tumors also could occur in this region, including primitive neuroectodermal tumor (n = 1), atypical teratoid/rhabdoid tumor (n = 1), anaplastic ependymoma (n = 1), lymphoma (n = 1), extraventricular neurocytoma (n = 1), gangliogliomas (n = 2), oligodendroglioma (n = 1), and dysembryoplastic neuroepithelial tumor (n = 1). CONCLUSIONS: Astrocytoma and GCT are the most common PBGRTs. Low-grade astrocytomas could benefit from maximal surgical resection, whereas GCTs merit neoadjuvant chemoradiation therapy followed by second-look surgery. We advocate routine testing of tumor markers and analysis of their clinical and radiologic features to optimize the therapeutic strategy.

Upfront Gamma Knife Surgery for Giant Central Neurocytoma.

BACKGROUND: In this report, we present the results of using upfront Gamma Knife surgery (GKS) in the management of giant central neurocytoma (CNC) (volume >50 mL) without the initial removal of the tumor mass. CASE DESCRIPTIONS: Two patients underwent GKS for histologically proven CNC. Clinical and imaging studies were performed to evaluate the response to treatment. GKS involved delivery doses of 12 or 13 Gy to the tumor margin at the isodose line of 50%. Tumor response to GKS appeared as early as 4-6 months after GKS, at which point a dramatic reduction in volume was observed. No adverse effects of radiation or new neurologic deficits were observed in either of the cases. In case 1, we observed a reduction in tumor volume from 69 to 20 mL at 6 months and a further reduction to 10.3 mL at 86 months. In case 2, we observed a reduction in tumor volume from 62 to 31 mL at 4 months with a further reduction to 22.5 mL at 30 months. The female patient (case 1) showed mild weakness in the right lower limb after the minimal surgical removal of tumor using the cortical approach. No additional neurologic deficits were observed after GKS. The young male patient (case 2) presented a complete recovery without any signs of headache at 3 months after GKS. CONCLUSIONS: Based on this initial experience, it appears that GKS is an effective treatment for CNC and may be used for upfront management in cases of indolent clinical symptoms, even when the tumor is very large.

Progression of atypical extraventricular neurocytoma to anaplastic ganglioglioma.

We report a childhood case of thalamic atypical extraventricular neurocytoma that progressed to highly anaplastic ganglioglioma after 8 years of dormancy after subtotal resection and chemotherapy. The neurocytoma displayed immunoreactivity only for synaptophysin, ß-catenin, S100, and CD56. The ganglioglioma acquired strong immunoreactivity for chromogranin, glial fibrillary acidic protein, neuron-specific enolase, and p53 and showed a very high proliferation rate approaching 50% in some areas. Tumor transformation was associated with overexpression of components of the sonic hedgehog and Wnt developmental signaling pathways, which are known to regulate tumor-initiating cells in malignant brain neoplasms.

Pediatric Central Neurocytoma.

Central neurocytomas are well-differentiated tumors of neuronal origin. These are relatively uncommon in the pediatric population. Anaplastic features reflected by brisk mitotic activity, microvascular proliferation, necrosis, and MIB-1 labeling index >2% or 3% have been proposed to indicate aggressive behavior. Because of its rarity, there is paucity of data regarding the histologic spectrum and outcome of central neurocytomas in children. With this short series, we describe our observations of the clinicopathologic characteristics and outcome of this tumor in children over a 5-year period.

Clinical characteristics and prognostic factors of brain central neurocytoma.

BACKGROUND & AIMS: This study is designed for the clinical characteristics and prognostic factors of central neurocytoma (CN). METHODS: CN patients from 2004 to 2012 were enrolled from the Surveillance Epidemiology and End Results (SEER) data. Clinical characteristics including age, sex, race, tumor size, tumor number, surgery, and radiation therapy were summarized. Univariate and multivariate analysis were performed to explore the prognostic factors of CN. RESULTS: CN tended to be borderline malignant and single lesion. Compared with other brain tumor (NCN), Patients with CN (CNs) were more likely to be female, young, and non-white race. Surgery was the primary treatment of CN. Univariate and Multivariate analysis indicated tumor number and surgery were both independent prognostic factors of CN (P < 0.05). Unifocal CNs had a lower mortality risk than multifocal ones (HR 0.167, 95% CI 0.052-0.537), surgery significantly reduced the death risk of CNs (HR 0.284, 95% CI 0.088-0.921). CONCLUSIONS: CN tend to be borderline malignant, single lesion, operated on. Most CNs are female and younger. single lesion and surgery are the independent positive prognostic factors of CN.

Central Versus Extraventricular Neurocytoma in Children: A Clinicopathologic Comparison and Review of the Literature.

BACKGROUND: Central neurocytomas (CN) are rare pediatric CNS tumors most often with a benign clinical course. Occasionally, these tumors occur outside the ventricles and are called extraventricular neurocytomas (EVN). We present a retrospective institutional analysis of children with neurocytoma with prolonged follow-up. PROCEDURE: Twelve patients were diagnosed with neurocytoma at our institution between 1993 and 2004. RESULTS: Six patients were male and the median age at diagnosis was 12 years (1.5 to 16 y). Seven patients had CN and 5 had EVN. Presenting symptoms included headaches (67%), vomiting (50%), nausea (33%), seizures (33%), and mental status changes (25%). Obstructive hydrocephalus was present at diagnosis in 42% of the cases. Younger age and seizures were more common in patients with EVN. Gross total resection (GTR) was achieved in 42% (5/12) of the patients. Patients with GTR received no adjuvant therapy upfront; 1 patient subsequently had recurrence with leptomeningeal disease. Patients with subtotal resection received additional treatment: 1 underwent reoperation (GTR), 2 patients received focal radiation, 2 patients received adjuvant chemotherapy, and 2 patients received craniospinal irradiation followed by chemotherapy. The 20-year overall survival for this cohort was 83% with event free survival of 56%. Overall survival for CNs was 100%, versus 40% for EVN. Event free survival for CNs was 57% and 53% for the EVNs. An MIB-1 fraction >2% was associated with worse prognosis. CONCLUSIONS: Neurocytomas are rare brain tumors in children usually cured with GTR. Adjuvant focal radiation therapy and/or chemotherapy may improve disease control in cases with subtotal resection, but case-by-case analysis should be done. EVNs might be associated with worse outcome due to a higher proliferative index.