Neurocytoma: a comprehensive review

Long-term outcomes of central neurocytoma - an institutional experience

INTRODUCTION

Central Neurocytoma (CN) is a rare, WHO grade 2 brain tumor that predominantly affects young adults. Gross total resection (GTR) is often curative for CNs, but the optimal treatment paradigm including incorporation of RT, following subtotal resection (STR) and for scarcer pediatric cases has yet to be established.

METHODS

Patients between 2001 and 2021 with a pathologic diagnosis of CN were reviewed. Demographic, treatment, and tumor characteristics were recorded. Recurrence free survival (RFS) and overall survival (OS) were calculated according to the Kaplan Meier-method. Post-RT tumor volumetric regression analysis was performed.

RESULTS

Seventeen adults (≥ 18 years old) and 5 children (< 18 years old) met the criteria for data analysis (n = 22). With a median follow-up of 6.9 years, there was no tumor-related mortality. Patients who received STR and/or had atypical tumors (using a cut-off of Ki-67 > 4%) experienced decreased RFS compared to those who received GTR and/or were without atypical tumors. RFS at 5 years for typical CNs was 67% compared to 22% for atypical CNs. Every pediatric tumor was atypical and 3/5 recurred within 5 years. Salvage RT following tumor recurrence led to no further recurrences within the timeframe of continued follow-up; volumetric analysis for 3 recurrent tumors revealed an approximately 80% reduction in tumor size.

CONCLUSION

We provide encouraging evidence that CNs treated with GTR or with RT after tumor recurrence demonstrate good long-term tumor control.

Imaging of supratentorial intraventricular masses in children: a pictorial review-part 2

PURPOSE

This article is the second in a two-part series aimed at exploring the spectrum of supratentorial intraventricular masses in children. In particular, this part delves into masses originating from cells of the ventricular lining, those within the septum pellucidum, and brain parenchyma cells extending into the ventricles. The aim of this series is to offer a comprehensive understanding of these supratentorial intraventricular masses, encompassing their primary clinical findings and histological definitions.

METHODS

We conducted a review and analysis of relevant epidemiological data, the current genetics/molecular classifications as per the fifth edition of the World Health Organization (WHO) Classification of Tumors of the Central Nervous System (WHO CNS5), and imaging findings. Each supratentorial intraventricular mass was individually evaluated, with a detailed discussion on its clinical and histological features.

RESULTS

This article covers a range of supratentorial intraventricular masses observed in children. These include colloid cysts, subependymal giant cell astrocytomas, ependymomas, gangliogliomas, myxoid glioneuronal tumors, central neurocytomas, high-grade gliomas, pilocytic astrocytomas, cavernous malformations, and other embryonal tumors. Each mass type is characterized both clinically and histologically, offering an in-depth review of their individual imaging characteristics.

CONCLUSION

The WHO CNS5 introduces notable changes, emphasizing the vital importance of molecular diagnostics in classifying pediatric central nervous system tumors. These foundational shifts have significant potential to impact management strategies and, as a result, the outcomes of intraventricular masses in children.

Cytological features of chordoid glioma: A case report with summary of prior published cases

Chordoid glioma is an uncommon low-grade glioma and is a CNS WHO grade 2 tumour in the current WHO 2021 classification. Predominantly it is seen in the third ventricle and in young adults. Although the histological features of chordoid glioma are well documented, there is sparse literature describing its cytological features. Here we describe the squash cytological features of a case of chordoid glioma along with summary of prior published cases. The smears tend to be quite cellular, the cells show mild pleomorphism, anisonucleosis, and absent mitotic activity. The background shows a distinctive bluish myxoid stroma. It can be mistaken for high grade glioma on squash cytology.

Clinicopathological features and treatment outcome of central neurocytoma: a single institute experience

Background

Despite the increased interest in publishing data on central neurocytoma, its management remains controversial. The overall incidence is approximately 0.5% of brain tumors. The reporting of institutional experience is of major need for such category of tumors to increase our knowledge and experience. In this study, we describe the clinical presentation, pathological data, and treatment outcomes of central neurocytoma.

Results

Medical records of patients with neurocytoma treated in our center from July 2008 to December 2018 were retrospectively reviewed. Extra ventricular neurocytomas were excluded from analysis due to the known aggressive behavior compared to central neurocytoma. Seventeen patients treated at our center as central neurocytoma were included in the study. The frequent clinical presentation was headaches (58.8%) and paresis (35.3%). Ten patients (58.8%) developed symptoms before the age of 30 years. All patients were treated with surgical resection. Gross total resection was performed in 11 cases (64.7%) and subtotal resection was performed in 3 cases (17.7%). Four patients developed disease progression following the first excision (23.5%), for which additional resection was performed. Two patients received fractionated radiotherapy; one after the first resection due to residual disease postoperatively and the other patient following the third excision due to multiple recurrences with radiotherapy doses of 50.4 Gy and 54 Gy, respectively. The median follow-up time was 51 months (range of 14–106). The 5-year progression-free survival was 70 ± 13%. The overall survival for our cohort of patients was 100%.

Conclusions

Central neurocytoma is a rare tumor of neuronal origin and surgery is the mainstay of treatment with a favorable prognosis. Adjuvant radiotherapy can be offered in patients with residual disease or multiple recurrences, especially in patients with tumors of high MIC-1 LI.

Central Neurocytoma with Hemorrhagic Presentation Case Report and Review of the Literature

Central neurocytoma (CN) is slow-growing rare intraventricular tumor that represents 0.25-0.5% of all intracranial tumors in adults. Typically, it is seen in young adults, yet with surgical resection, it has excellent prognosis. Due to CN rarity and its feature similarities with other common tumors, misdiagnosis can be an issue. With no pathognomonic clinical features of CN, a proper diagnosis can be achieved by radiological imaging, magnetic resonance spectroscopy, histopathology assessment, and immunohistochemistry. Therefore, this is a case report of a 17-year-old male who presented with right lateral ventricular CN with intraventricular hemorrhage. Subtotal tumor resection was carried out via right transcortical approach. Subtle improvement for the patient condition was noted.

Clinical Outcome After Microsurgical Resection of Central Neurocytoma: A Single-Centre Analysis of 15 Years

Objective: This study aimed to explore the immediate postoperative and long-term outcomes of central neurocytoma (CN) based on 15 years of experience in our institution.

Methods: This single-institution study collected data of 43 patients with CN who underwent surgery between 2005 and 2020. We reviewed data of clinical, immediate postoperative outcome, and long-term outcome of patients. More specifically, we divided complications into neurological and regional complications groups.

Results: Among the 43 patients with CN who underwent surgery, the transcortical (72.1%) or transcallosal (25.6%) approach was used. There were 18 patients (41.9%) who complained about postoperative neurological complications, including motor weakness (25.6%), memory deficit (18.6%), aphasia (7.0%), and seizure (4.7%). In addition, 18 patients suffered postoperative regional complications such as hydrocephalus (2.3%), hematoma (34.9%), infection (4.7%), and subcutaneous hydrops (2.3%). Only one-quarter of patients had suffered permanent surgical complications. The majority of patients recovered from the deficit and could turn back to normal life. There were no significant differences in the clinical outcomes between transcortical and transcallosal approaches. At a median follow-up of 61.8 months, the 5-year overall survival and progression-free survival were 87.0 and 74.0%, respectively. A multivariate Cox model analysis showed that the extent of resection was not related to progression-free survival. However, the extent of resection was significantly associated with overall survival, and gross total resection decreased the risk of death.

Conclusions: Patients with CN show favorable outcomes after surgery. The transcortical and transcallosal approaches have similar postoperative complication rates and long-term follow-up outcomes. In terms of long-term prognosis, maximal safety resection should be the first choice of CN.

Impact of Adjuvant Radiotherapy in Patients with Central Neurocytoma: A Multicentric International Analysis

Simple Summary

Central neurocytoma is a rare tumor accounting for <0.5% of all intracranial tumors. We analyzed 33 patients treated with surgical resection with or without radiotherapy from ten closely cooperating institutions in Germany, Egypt, and Jordan. Patients who received radiotherapy had longer progression-free survival with an acceptable toxicity profile.

Abstract

Background: Central neurocytoma (CN) is a rare tumor accounting for <0.5% of all intracranial tumors. Surgery ± radiotherapy is the mainstay treatment. This international multicentric study aims to evaluate the outcomes of CNs patients after multimodal therapies and identify predictive factors. Patients and methods: We retrospectively identified 33 patients with CN treated between 2005 and 2019. Treatment characteristics and outcomes were assessed. Results: All patients with CN underwent surgical resection. Radiotherapy was delivered in 19 patients. The median radiation dose was 54 Gy (range, 50–60 Gy). The median follow-up time was 56 months. The 5-year OS and 5-year PFS were 90% and 76%, respectively. Patients who received radiotherapy had a significantly longer PFS than patients without RT (p = 0.004) and a trend towards longer OS. In addition, complete response after treatments was associated with longer PFS (p = 0.07). Conclusions: Using RT seems to be associated with longer survival rates with an acceptable toxicity profile.

Gamma Knife radiosurgery as a primary treatment for central neurocytoma

OBJECTIVE

This study was performed to evaluate the role of Gamma Knife radiosurgery (GKRS) as a primary treatment for central neurocytomas (CNs).

METHODS

The authors retrospectively assessed the treatment outcomes of patients who had undergone primary treatment with GKRS for CNs in the period between December 2001 and December 2018. The diagnosis of CN was based on findings on neuroimaging studies. The electronic medical records were retrospectively reviewed for additional relevant preoperative data, and clinical follow-up data had been obtained during office evaluations of the treated patients. All radiographic data were reviewed by a dedicated neuroradiologist.

RESULTS

Fourteen patients were treated with GKRS as a primary treatment for CNs in the study period. Seven patients (50.0%) were asymptomatic at initial presentation, and 7 (50.0%) presented with headache. Ten patients (71.4%) were treated with GKRS after the diagnosis of CN based on characteristic MRI findings. Four patients (28.6%) initially underwent either stereotactic or endoscopic biopsy before GKRS. The median tumor volume was 3.9 cm3 (range 0.46–18.1 cm3). The median prescription dose delivered to the tumor margin was 15 Gy (range 5.5–18 Gy). The median maximum dose was 30 Gy (range 11–36 Gy). Two patients were treated with fractionated GKRS, one with a prescription dose of 21 Gy in 3 fractions and another with a dose of 22 Gy in 4 fractions. Control of tumor growth was achieved in all 14 patients. The median volume reduction was 26.4% (range 0%–78.3%). Transient adverse radiation effects were observed in 2 patients but resolved with improvement in symptoms. No recurrences were revealed during the follow-up period, which was a median of 25 months (range 12–89 months).

CONCLUSIONS

Primary GKRS for CNs resulted in excellent tumor control rates without recurrences. These results suggest that GKRS may be a viable treatment option for patients with small- to medium-sized or incidental CNs.

[Central neurocytomas: long-term treatment outcomes]

Central neurocytoma is a rare benign brain tumor. These tumors may be giant and accompanied by compression of ventricular system and surrounding structures. Modern treatment of brain neurocytoma includes extended resection and restoration of normal CSF circulation. Surgical treatment does not often lead to total resection of these tumors. Redo resection was preferred in patients with tumor progression for a long time. In the last decade, various authors report stereotactic irradiation for continued tumor growth to ensure local growth control. This study was aimed at evaluation of postoperative outcomes in patients with brain neurocytomas, as well as treatment of tumor progression in long-term period.

OBJECTIVE

To analyze recurrence-free survival in patients with brain neurocytomas, risk factors of recurrence-free survival, effectiveness of various treatments for tumor progression and delayed complications.

MATERIAL AND METHODS

Long-term postoperative follow-up data of patients with brain neurocytomas are reported in the manuscript. We analyzed recurrence-free survival and risk factors of recurrence-free survival, treatment outcomes in patients with progression of brain neurocytomas, long-term complications and their prevention.

RESULTS

Follow-up included 84 out of 115 patients with brain neurocytoma after surgical treatment in 2008-2017. Follow-up period ranged from 2 to 10 years (mean 6 years) after resection. Most patients had regression of neurological symptoms after surgery. Continued tumor growth within 12-96 months after surgery occurred in 26 (30.19%) out of 84 patients (19 cases after partial resection and 7 cases after total resection according to MRI data). Two-year recurrence-free survival was 94%, 5-year survival - 83%. Risk factors of continued tumor growth were resection quality and Ki-67 index. Redo resection was performed in 7 cases. Eleven patients underwent stereotactic irradiation for tumor progression. Indications for stereotactic irradiation of central neurocytoma are MR data on continued growth of lateral ventricle tumor without signs of ICH and CSF flow impairment. There were no cases of hemorrhage inside the residual tumor and CSF flow impairment in early postoperative period after redo resection. In all cases (n=11), stereotactic irradiation (mean follow-up 2.5 years) ensured satisfactory control of tumor growth with reduction of the neoplasm in 4 cases and no tumor growth in 7 cases.

CONCLUSION

Resection of central neurocytoma ensures long-term recurrence-free period. The main causes of tumor recurrence are partial resection and high proliferative activity (Ki-67 index over 5%). Redo resection is advisable for tumor progression followed by CSF flow impairment. In case of continued growth of neurocytoma without signs of intracranial hypertension, stereotactic irradiation with various fractionation modes ensures effective and safe control of tumor growth.

Gamma Knife radiosurgery for the treatment of central neurocytoma: a single-institution experience of 25 patients

Central neurocytomas (CNs) are extremely rare tumors that account for 0.1-0.5% of all intracranial neoplasms. Recently, Gamma Knife radiosurgery (GKRS) has become a treatment option in patients with CN. We aimed to evaluate the efficacy and safety of GKRS in 25 CN patients and review the results along with relevant literature. GKRS patient database was searched, and 25 patients who underwent GKRS for CN between 2009 and 2018, were evaluated retrospectively. The study cohort included 15 female and ten male patients with a median age of 32 years (range, 5-60). The most common presenting symptom was headache (88%). The neurological examination was unremarkable in all patients, except for one patient with decreased vision. Twenty patients (80%) had a history of surgical resection. Most of the tumors (92%) were located in the ventricles, and the median tumor volume was 4.8 cm³ (range, 0.8-28.1). The median marginal dose was 14 Gy (range, 12-15) to a median isodose of 50% (range, 40-50). Following a median follow-up of 80 months (range, 36-138), local tumor control was achieved in 100% of patients. Distant recurrence was observed in one patient (4%). No adverse radiation effect was observed. Regarding non-specific post-GKRS symptoms, one patient experienced a prolonged headache, and one epileptic patient experienced a brief partial seizure. In our patient cohort, GKRS yielded favorable local tumor control (100%) during a median follow-up of 6.6 years. Our series demonstrates that GKRS is an effective and safe treatment option for patients with primary or residual CNs.

A rare diagnosis of an extraventricular neurocytoma

Background:

Extraventricular neurocytoma (EVN) is an extremely rare neoplasm of the central nervous system. As reported, it arises in a variety of locations, but mainly within the cerebral hemispheres. Despite its histological similarity with central neurocytoma (CN), EVN occurs outside the ventricular system and, in 2007, was recognized by the World Health Organization as a separate entity.

Case Description:

A 39-year-old man, with a ventriculoperitoneal shunt inserted for communicating hydrocephalus, was admitted at our Unit of Neurosurgery with a 1-month history of gait disturbance, postural instability, speech disorders, and occasional incontinence. Computed tomography scan and magnetic resonance imaging showed a mixed-density neoplasm in the left frontotemporal area, with anterior cerebral falx shift, and perilesional edema. The patient underwent surgical procedure; microsurgical excision of the lesion was performed through left pterional approach. Histopathological and immunohistochemical examination revealed monomorphic round cells of the neuronal lineage, with a percentage of Ki-67 positive nuclei <5% and no evidence of mitosis or necrotic areas. According to radiologic features, this pattern was compatible with the diagnosis of EVN. Patient had a favorable recovery and he is still in follow-up.

Conclusion:

Because of their rarity, clinical, radiologic, and histopathological characteristics of EVNs are not yet well defined, as well as the optimal therapeutic management. Whereas EVNs are rarely described in literature, we aimed to share and discuss our experience along with a review of the published literature.

Clinico-radiological characteristics, histo-pathological features and long-term survival outcomes in central neurocytoma: A single-institutional audit

Central neurocytoma is a rare benign brain tumor that typically arises from the subependymal lining of the lateral ventricles in young adults and is generally associated with excellent survival following neurosurgical excision alone. This is a retrospective clinical audit of biopsy-proven neurocytoma registered between 2004 and 2019 at a single institution in India. All time-to event outcomes were analyzed using Kaplan-Meier method and compared with the log-rank test. Any p-value <0.05 was considered statistically significant. A total of 66 patients with neurocytoma were included in the descriptive analysis. Median age of study cohort was 31 years with equitable gender ratio. Majority (83%) of tumors were intraventricular, lateral ventricle being the commonest location. Following maximal safe resection, patients were generally kept on close clinico-radiological surveillance. Most patients (80%) had typical World Health Organization (WHO) grade II neurocytoma with remaining 20% showing histological atypia and/or high-grade features. Outcome analysis was restricted to 35 patients with relevant treatment details and adequate follow-up information. Six patients experienced recurrent/progressive disease with 2 documented deaths. At a median follow up of 52 months, 5-year Kaplan-Meier estimates of progression-free survival and overall survival were 93.3% and 96.8% respectively. Three patients developed delayed recurrence (>5-years after initial diagnosis) underscoring the importance of long-term follow-up. Atypical/high-grade histology was associated with inferior survival that may stand to benefit with upfront adjuvant radiotherapy. This represents the largest single-institution series of central neurocytoma and demonstrates excellent outcomes with adequate surgical resection alone, reserving radiotherapy for large residual tumor, recurrent disease, and/or atypical high-grade histology.

Intraventricular neuroepithelial tumors: surgical outcome, technical considerations and review of literature

Background

Intraventricular neuroepithelial tumors (IVT) are rare lesions and comprise different pathological entities such as ependymomas, subependymomas and central neurocytomas. The treatment of choice is neurosurgical resection, which can be challenging due to their intraventricular location. Different surgical approaches to the ventricles are described. Here we report a large series of IVTs, its postoperative outcome at a single tertiary center and discuss suitable surgical approaches.

Methods

We performed a retrospective chart review at a single tertiary neurosurgical center between 03/2009–05/2019. We included patients that underwent resection of an IVT emphasizing on surgical approach, extent of resection, clinical outcome and postoperative complications.

Results

Forty five IVTs were resected from 03/2009 to 05/2019, 13 ependymomas, 21 subependymomas, 10 central neurocytomas and one glioependymal cyst. Median age was 52,5 years with 55.6% (25) male and 44.4% (20) female patients. Gross total resection was achieved in 93.3% (42/45). 84.6% (11/13) of ependymomas, 100% (12/21) of subependymomas, 90% (9/10) of central neurocytomas and one glioependymal cyst were completely removed. Postoperative rate of new neurological deficits was 26.6% (12/45). Postoperative new permanent cranial nerve deficits occurred in one case with 4th ventricle subependymoma and one in 4th ventricle ependymoma. Postoperative KPSS was 90% (IR 80–100). 31.1% of the patients improved in KPSS, 48.9% remained unchanged and 20% declined. Postoperative adverse events rate was 20.0%. Surgery-related mortality was 2.2%. The rate of shunt/cisternostomy-dependent hydrocephalus was 13.3% (6/45). 15.4% of resected ependymomas underwent adjuvant radiotherapy. Mean follow-up was 26,9 (±30.1) months.

Conclusion

Our surgical findings emphasize satisfactory complete resection throughout all entities. Surgical treatment can remain feasible, if institutional experience is given. Satisfying long-term survival and cure is possible by complete removal. Gross total resection should always be performed under function-remaining aspects due to mostly benign or slow growing nature of IVTs. Further data is needed to evaluate standard of care and alternative therapy options in rare cases of tumor recurrence or in case of patient collective not suitable for operative resection.

Atypical Central Neurocytoma: An Investigation of Prognostic Factors

OBJECTIVE

Central neurocytoma is a rare nervous tissue benign neoplasm. A subset of central neurocytoma has unfamiliar aggressive tendency: so-called atypical central neurocytoma (ACN). This retrospective study aims to analyze the prognostic factors and the impact of various therapy tools on atypical central neurocytoma.

METHODS

Twenty-two patients diagnosed with ACN between January 2009 and March 2018 were included. Data collected included the patient's age, gender, tumor location, presenting symptoms, and treatment received. Patients were followed up to detect recurrence and to assess survival.

RESULTS

Median overall survival was 57 months, with a 5-year survival of 35%. Better survival was observed for patients <35 years old (66 vs. 47 months; P = 0.061) and patients with gross total resection over subtotal resection or biopsy (76, 45, and 22 months, respectively; P < 0.0001). Patients with a tumor located in the posterior half of the lateral ventricle had better survival, with no statistical significance (P = 0.053). Multivariate analysis showed prognostic significance with the extent of resection (P = 0.000). Progression-free survival ranged from 6 to 82 months, with a median value of 38 months and showed a significant relation with subtotal resection compared with biopsy (P = 0.006). Recurrence was less in patients who received radiotherapy and was statistically significant (P = 0.007).

CONCLUSIONS

Long-term survival is possible for patients with atypical central neurocytomas treated with surgery and postoperative radiation. Multivariate analysis confirmed that gross total resection was an independent prognostic factor for survival. Adjuvant radiotherapy reduces tumor recurrence, especially after incomplete surgery.

Individual Treatment Decisions for Central Neurocytoma

Objective: Central neurocytomas (CNs) are rare, and this has resulted in a paucity of information and a lack of clarity regarding their optimal management. This study aimed to explore individual treatment strategies for CNs and the benefits of these strategies for patients.

Methods: This single-center study retrospectively analyzed data from 67 patients with CNs who underwent surgery. Based on the extent of resection, patients were divided into complete and incomplete resection groups. The patients were followed, and overall survival (OS) and progression-free survival (PFS) were determined.

Results: Of 55 patients (82.1%) who underwent complete resections, 24 received radiotherapy (24/55, 43.6%). Of 12 patients who underwent incomplete resections, 9 (9/12, 75.0%) received radiotherapy. The OS (p = 0.003) and PFS (p = 0.006) intervals were significantly longer in the complete resection group than in the incomplete resection group. Postoperative radiotherapy did not affect OS (p = 0.129) or PFS (p = 0.233) in the complete resection group. In the incomplete resection group, postoperative adjuvant radiotherapy prolonged patient survival significantly (p = 0.021). PFS was significantly longer among patients who underwent complete resection without radiotherapy than in those who underwent incomplete resection followed by radiotherapy (p = 0.034). Functional dependence on admission, which was defined as a Karnofsky Performance Status score <70, was an independent risk factor associated with long-term survival in patients with CN. Postoperative complications were not associated with the amount of tumor resected. The prognosis of patients aged ≥ 50 years was relatively poor. The atypical CN recurrence rate was relatively high (7.8%).

Conclusions: To protect function as much as possible, complete tumor resection should be the first choice of treatment for CN. After gross total resection, adjuvant radiotherapy is not acceptable. Postoperative adjuvant radiotherapy improves the prognosis of patients who have undergone incomplete tumor resections. Adjuvant radiotherapy is not recommended after complete resections of atypical CNs, and close follow-up with imaging is required. Our findings can help guide decision-making regarding the treatment of CNs and could potentially maximize the benefits of treatment for patients with CN.

Glioneuronal tumors: clinicopathological findings and treatment options

Glioneuronal tumors are very rare CNS neoplasms that demonstrate neuronal differentiation, composed of mixed glial and neuronal cells. The majority of these lesions are low grade and their correct classification is crucial in order to avoid misidentification as ‘ordinary’ gliomas and prevent inappropriate aggressive treatment; nevertheless, precise diagnosis is a challenge due to phenotypic overlap across different histologic subtype. Surgery is the standard of therapeutic approach; literature concerning the benefit of adjuvant treatments is inconclusive and a globally accepted treatment of recurrence does not exist. Targetable mutations in the genes BRAF and FGFR1/2 are recurrently found in these tumors and could take a promising role in future treatment management.

Central neurocytoma originating in third ventricle with expansion into the cerebral aqueduct and fourth ventricle: Case report and review of literature

BACKGROUND

Central Neurocytomas (CNs) are rare brain tumors, making up less than 1% of all primary tumors within the CNS. They are commonly located in the lateral ventricles, and often present with visual changes and symptoms of obstructive hydrocephalus. Histopathology shows characteristics similar to ependymomas and oligodendrogliomas, however tumor cells display neuronal differentiation, and immunohistochemical stains typically for synaptophysin. Gross total resection is the most important prognostic indicator of survival.

CASE DESCRIPTION

We describe the case of a 48-year-old male with a CN originating in the third ventricle with expansion through the cerebral aqueduct into the fourth ventricle. He presented with bi-frontal headaches, imaging revealed an avidly enhancing tumor occupying the inferior third ventricle, cerebral aqueduct, with expansion into the fourth ventricle. An interhemispheric craniotomy with a transcallosal transchoroidal approach to the third ventricle was performed, this provided a trajectory that paralleled the long axis of the tumor. Postoperative imaging confirmed a near total resection with linear residual enhancement on the anterior wall of the fourth ventricle. Intensity modulated radiotherapy was performed, 7-month follow-up imaging was clean.

CONCLUSION

CNs are rare brain tumors, most commonly located within the lateral ventricles. We describe a rare case of a CN spanning from the third ventricle into the cerebral aqueduct and fourth ventricle. To our knowledge, this is only the fourth reported case of such a tumor. Surgical approach must be carefully selected, as gross total resection is the most important prognostic indicator.

Central neurocytoma: SNP array analyses, subtel FISH, and review of the literature

The central neurocytoma (CN) is a rare brain tumor with a frequency of 0.1-0.5% of all brain tumors. According to the World Health Organization classification, it is a benign grade II tumor with good prognosis. However, some CN occur as histologically "atypical" variant, combined with increasing proliferation and poor clinical outcome. Detailed genetic knowledge could be helpful to characterize a potential atypical behavior in CN. Only few publications on genetics of CN exist in the literature. Therefore, we performed cytogenetic analysis of an intraventricular neurocytoma WHO grade II in a 39-year-old male patient by use of genome-wide high-density single nucleotide polymorphism array (SNP array) and subtelomere FISH. Applying these techniques, we could detect known chromosomal aberrations and identified six not previously described chromosomal aberrations, gains of 1p36.33-p36.31, 2q37.1-q37.3, 6q27, 12p13.33-p13.31, 20q13.31-q13.33, and loss of 19p13.3-p12. Our case report contributes to the genetic knowledge about CN and to increased understanding of "typical" and "atypical" variants.

Atypical central neurocytoma with novel EWSR1-ATF1 fusion and MUTYH mutation detected by next-generation sequencing

We present the case of a 13-year-old boy with a very unusual periventricular atypical central neurocytoma with unique molecular features treated with subtotal surgical resection and photon intensity-modulated radiotherapy. Histological features were most consistent with atypical central neurocytoma. However, next-generation sequencing analysis revealed a novel EWSR1-ATF1 gene fusion (EWSR1-ATF1) as well as a MUTYH mutation. The EWSR1-ATF1 raised the possibility of Ewing sarcoma or angiomatoid fibrous histiocytoma, however, FLI-1 immunohistochemistry was negative. MUTYH mutations have been reported in diffuse midline paediatric glioma. The role of EWSR1-ATF1 and MUTYH mutations in central nervous system tumours is not well established. We present the first case of EWSR1-ATF1 and MUTYH mutation in a rare paediatric atypical central neurocytoma. Further studies are indicated to elucidate the consequences of these gene alterations in the context of paediatric central nervous system tumours as well as to investigate the potential role for targeted therapies.

Tumor control of third ventricular central neurocytoma after gamma knife radiosurgery in an elderly patient: A case report and literature review

RATIONALE

Central neurocytoma is rare benign tumor that occurs in high probability in young adults in the lateral ventricle. Herein, we report an unusual case of an elderly woman who was diagnosed with central neurocytoma isolated to the third ventricle. This deeply located tumor was effectively treated using gamma knife radiosurgery (GKR).

PATIENT CONCERNS

A 79-year-old woman was admitted to hospital with gait disturbance and cognitive dysfunction.

DIAGNOSIS

Brain magnetic resonance imaging (MRI) revealed a homogenously enhancing multilobulated mass in the posterior third ventricle measuring 1.8 cm in size. The tumor was diagnosed as a central neurocytoma isolated to the third ventricle.

INTERVENTIONS

Neuronavigation-guided endoscopic third ventriculostomy and biopsy were performed. One week following surgery, GKR was performed using a prescribed dose of 14 Gy with 50% isodose lines, and a target volume of 1.62 cc.

OUTCOMES

Three months after GKR, brain MRI revealed a decrease in the size (to 1.4 cm) of the multilobulated strong enhancing mass in the posterior third ventricle, and the patient's symptom of confusion was improved.

LESSONS

Previous studies have reported that tumors in unusual locations, such as those isolated to the third ventricle, are different according to age, either in young children or elderly individuals. Although complete surgical resection is an effective treatment for central neurocytoma, it is often difficult to approach these tumors through surgery. GKR could, therefore, be an alternative primary treatment option for deeply located central neurocytomas in elderly patients.

Mesial temporal extraventricular neurocytoma (mtEVN): A case report and literature review

Aim

We describe a case of mesial temporal extraventricular neurocytoma (mtEVN) in a 23-year-old male presenting with drug-resistant seizures and review the literature on this rare tumor.

Methods

A PubMed search was queried using the MeSH term "neurocytoma" and key search terms "extraventricular", "temporal", and "epilepsy". Titles and abstracts were screened for temporal neurocytomas. References were reviewed to identify further studies.

Results

Twenty case reports were selected comparing the presentation, radiological, histopathological, and surgical outcomes of neocortex temporal EVNs (ntEVN) and mtEVNs.

Conclusion

Gross total resection of mtEVNs under intraoperative electrocorticography monitoring typically affords an excellent prognosis and successful seizure control.

Intramedullary central neurocytoma of the thoracic spinal cord: A case report and literature review

Central neurocytomas (CNs) are rare benign tumors located in the central nervous system with a good prognosis. These tumors are predominantly located in the lateral ventricle near the foramen of Monro or in the third ventricle. Similar tumors that are located outside the ventricle are also called extraventricular neurocytomas, and have an even lower morbidity. Until now, several tumors have been identified in the thalamus, cerebellum, pons, medulla oblongata and spinal cord. In total, 24 cases of neurocytomas located in the spinal cord have been reported in English journals. The present study reported a patient with an intramedullary central neurocytoma of the thoracic spinal cord, diagnosed from clinical features, imaging findings, pathology and immunohistochemistry. The present case report also outlined the prognosis of the patient and reviewed the literature currently available on CNs located in the spinal cord.

Extraventricular Neurocytoma in the Left Frontal Lobe: A Case Report and Literature Review

BACKGROUND

Neurocytoma is a rare brain neoplasm of neuroepithelial origin that occurs predominantly in the ventricular system adjacent to the interventricular foramen and septum pellucidum. However, extraventricular neurocytoma is an extremely rare entity, with poor clinical, radiologic, and histopathological characterization. Here we report a case of an extraventricular parafalcine neurocytoma in the left frontal lobe. We also examine previously reported cases of extraventricular neurocytoma in an attempt to provide an up-to-date summary of the condition.

METHODS

A literature search was performed using PubMed with specific key terms, inclusion criteria, and exclusion criteria. Selected case studies and case series were then compared, and statistical analyses were performed where appropriate. We report a 59-year-old woman presenting with weakness in her right leg and urinary incontinence. Physical examination revealed muscle strength of grade 3/5 in the right lower extremity. Brain magnetic resonance imaging showed a parafalcine mass in the left frontal lobe, with perilesional edema; the cerebral falx and lateral ventricle were shifted due to the compression. Gross total resection was performed.

RESULTS

Histopathological examination revealed a neurocytoma. Immunohistochemical staining showed diffuse positivity for synaptophysin. MIB-1 staining for Ki-67 antibody showed a labeling index of 20%. No adjuvant radiation or chemotherapy was administered. Brain computed tomography performed at a 3-month follow-up showed no signs of recurrence.

CONCLUSION

Extraventricular neurocytoma occurring in the brain parenchyma is a very rare central nervous system tumor. Its clinical and radiologic manifestations are nonspecific. The diagnosis depends on histopathological and immunohistochemical examination. Surgical resection should be the first-choice treatment.

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.

Clinical Features, Treatment, and Long-term Outcomes of Central Neurocytoma: A 20-Year Experience at a Single Center

OBJECTIVE

Central neurocytoma (CN) is a rare central nervous system tumor the optimal management strategy of which remains controversial because of their rarity. Detailed information on CN is necessary to establish optimal management strategies. The purpose of this study was to show the clinical features, treatments, and long-term clinical outcomes of CN.

METHODS

A total of 63 patients with CN were surgically treated between 1995 and 2016 at West China Hospital. All pathologically proven CN cases were identified. Epidemiologic characteristics, clinical features, imaging features, functional outcomes, overall survival, and progression-free survival according to multimodal treatments were reviewed retrospectively.

RESULTS

There were 29 males and 34 females, with a median age of 29 years (range, 15-58 years). Thirty-four patients underwent gross total resection (GTR) and 29 patients underwent subtotal resection (STR). The surgical approaches to CNs in this study included a transcortical approach (39 cases) and an interhemispheric transcallosal approach (24 cases). There were no differences in functional outcomes or initial extent of resection according to the surgical approach used. The extent of resection was GTR in 34 patients (54.0%), and STR in 29 patients (46.0%). At the median follow-up of 74 months (range, 6-205 months), the actuarial 5-year and 10-year overall survival were 93.3% and 85.4%. At the last follow-up, 8 patients had experienced tumor progression. The 5-year and 10-year progression-free rate was 73.4% and 57.5%. The initial extent of resection and multimodal treatment was not related to overall survival; however, the actuarial local control rate differed significantly according to the initial extent of resection and multimodal treatment.

CONCLUSIONS

CN is a rare type of World Health Organization grade II primary brain tumor with a tendency to recur. Complete resection of CNs with maximal safety remains the primary treatment to minimize local progression. Adjuvant radiotherapy should be considered in patients receiving incomplete resection. The long-term clinical outcomes of CN after multimodal treatment seem to be satisfactory.

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.

Systematic Analysis of Clinical Outcomes Following Stereotactic Radiosurgery for Central Neurocytoma

Central neurocytoma (CN) typically presents as an intraventricular mass causing obstructive hydrocephalus. The first line of treatment is surgical resection with adjuvant conventional radiotherapy. Stereotactic radiosurgery (SRS) was proposed as an alternative therapy for CN because of its lower risk profile. The objective of this systematic analysis is to assess the efficacy of SRS for CN. A systematic analysis for CN treated with SRS was conducted in PubMed. Baseline patient characteristics and outcomes data were extracted. Heterogeneity and publication bias were also assessed. Univariate and multivariate linear regressions were used to test for correlations to the primary outcome: local control (LC). The estimated cumulative rate of LC was 92.2% (95% confidence interval: 86.5-95.7%, p<0.001). Mean follow-up time was 62.4 months (range 3-149 months). Heterogeneity and publication bias were insignificant. The univariate linear regression models for both mean tumor volume and mean dose were significantly correlated with improved LC (p<0.001). Our data suggests that SRS may be an effective and safe therapy for CN. However, the rarity of CN still limits the efficacy of a quantitative analysis. Future multi-institutional, randomized trials of CN patients should be considered to further elucidate this therapy.

Ventricular Central Neurocytoma: Rate of Shunting and Outcome 2 Years After Total and Subtotal Excision

BACKGROUND

Central neurocytoma is an intraventricular tumor that affects young adults. It has a favorable prognosis after adequate surgical intervention; however, an aggressive course may take place in some cases.

OBJECTIVE

The objective of the study was to evaluate the rate of shunting and the outcome of control measures in patients with central neurocytoma submitted to total and subtotal excision.

METHODS

Twelve patients were included in this study, with a follow-up of 24 months. Data collected included: age, sex, clinical presentation, early morbidity and mortality, radiological findings (tumor location, features, residual, recurrence, and hydrocephalus). All patients underwent surgery for total or subtotal excision through a transcortical approach. External Ventricular Drain (EVD) was inserted then removed or replaced by a shunt. Histopathology and the MIB index were used to confirm diagnosis and guide the follow-up; adjuvant radiotherapy or Gamma Knife radiosurgery were used for residual tumor or recurrence.

RESULTS

The ages of the patients ranged from 14 to 48 years. Two patients died early, after total and subtotal excision, from sepsis and thalamic infarction, respectively. Six patients (60 %) had a total excision; two of them had a high MIB index and showed small recurrence at 12 months and 18 months, respectively, and received Gamma Knife radiosurgery. One of the six patients with total excision needed a shunt, and no shunt was needed in the four otherpatients; a subtotal excision was done for four patients (40 %). An early shunt was inserted for two of these patients, radiosurgery-controlled for one patient, while radiotherapy was used for control in the other three patients; radiotherapy control failed in one patient, who underwent a second surgery at 18 months.

CONCLUSION

Central neurocytoma may have a favorable prognosis, with a lower incidence of shunt insertion throughout its course than that for other intraventricular tumors, if total removal is achieved.

Central Neurocytoma: A Review of Clinical Management and Histopathologic Features

Central neurocytoma (CN) is a rare, benign brain tumor often located in the lateral ventricles. CN may cause obstructive hydrocephalus and manifest as signs of increased intracranial pressure. The goal of treatment for CN is a gross total resection (GTR), which often yields excellent prognosis with a very high rate of tumor control and survival. Adjuvant radiosurgery and radiotherapy may be considered to improve tumor control when GTR cannot be achieved. Chemotherapy is also not considered a primary treatment, but has been used as a salvage therapy. The radiological features of CN are indistinguishable from those of other brain tumors; therefore, many histological markers, such as synaptophysin, can be very useful for diagnosing CNs. Furthermore, the MIB-1 Labeling Index seems to be correlated with the prognosis of CN. We also discuss oncogenes associated with these elusive tumors. Further studies may improve our ability to accurately diagnose CNs and to design the optimal treatment regimens for patients with CNs.

Clinical outcome and prognostic factors for central neurocytoma: twenty year institutional experience

Central neurocytomas are uncommon intraventricular neoplasms whose optimal management remains controversial due to their rarity. We assessed outcomes for a historical cohort of neurocytoma patients and evaluated effects of tumor atypia, size, resection extent, and adjuvant radiotherapy. Progression-free survival (PFS) was measured by Kaplan-Meier and Cox proportional hazards methods. A total of 28 patients (15 males, 13 females) were treated between 1995 and 2014, with a median age at diagnosis of 26 years (range 5-61). Median follow-up was 62.2 months and 3 patients were lost to follow-up postoperatively. Thirteen patients experienced recurrent/progressive disease and 2-year PFS was 75% (95% CI 53-88%). Two-year PFS was 48% for MIB-1 labeling >4% versus 90% for ≤4% (HR 5.4, CI 2.2-27.8, p = 0.0026). Nine patients (32%) had gross total resections (GTR) and 19 (68%) had subtotal resections (STR). PFS for >80% resection was 83 versus 67% for ≤80% resection (HR 0.67, CI 0.23-2.0, p = 0.47). Three STR patients (16%) received adjuvant radiation which significantly improved overall PFS (p = 0.049). Estimated 5-year PFS was 67% for STR with radiotherapy versus 53% for STR without radiotherapy. Salvage therapy regimens were diverse and resulted in stable disease for 54% of patients and additional progression for 38 %. Two patients with neuropathology-confirmed atypical neurocytomas died at 4.3 and 113.4 months after initial surgery. For central neurocytomas, MIB-1 labeling index >4% is predictive of poorer outcome and our data suggest that adjuvant radiotherapy after STR may improve PFS. Most patients requiring salvage therapy will be stabilized and multiple modalities can be effectively utilized.

Primary Neurocytoma in the Spinal Cord

Central neurocytoma is defined as an intraventricular benign brain tumor. Extra-ventricular location of central neurocytoma is rare: only nine cases of spinal neurocytoma had been reported in the English literature. We hereby present a case of atypical neurocytoma involving unusual long segments (8-segment) of cervico-thoracic spinal cord in a 29-year-old woman with emphasis on pre- and post-surgical neuroimaging, pathological correlation, and review the pertinent literature.

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.

Extraventricular neurocytoma in the left temporal lobe: A case report and review of the literature

Central neurocytoma (CNC) often develops in the ventricular system adjacent to the interventricular foramen and septum pellucidum. According to the World Health Organization, CNCs are classified as grade II tumors, and in recent years it has been reported that CNCs have occasionally occurred in rare areas of the central nervous system. The current study describes a rare case of CNC located in the left temporal lobe of a 49-year-old man, who had been experiencing headaches for 3 weeks. Computed tomography identified a round, well-demarcated, 3.3-cm tumor in the left temporal lobe. The patient underwent surgery and the tumor was totally resected. Histological analysis demonstrated that the resected tumor tissue contained clusters of small cells with regular nuclear morphology, and round nuclei with fine chromatin. Immunohistochemically, neuronal differentiation markers, including synaptophysin and neuronal nuclear antigen, were expressed in the tumor cells. Histopathological examination of the resected tissue confirmed a diagnosis of extraventricular neurocytoma. Magnetic resonance imaging was performed at 3 months post-surgery and demonstrated no evidence of tumor recurrence.

The typical and atypical MR imaging findings of central neurocytomas: Report on eighteen cases and review of the literature

There were few studies have documented the MRI features of typical and atypical CNCs for diagnosis and therapeutic modalities. Here, 18 histopathologically confirmed cases of intracranial CNCs (8 men and 10 women with a mean age of 28.3 years, range 10-64 years) were retrospectively analyzed. The histopathological and immunohistochemical features were also assessed. On MR imaging, the 14 typical cases of CNCs showed relatively round, lobulated tumor masses in the body of the right lateral ventricle (5 cases), left lateral ventricle (4 cases), third ventricles (2 cases), and midline (3 cases). These typical CNCs masses contained clusters of cysts of varying sizes and "soap bubble" appearance on T2WI; they showed mild to moderate heterogeneously enhancement on T1WI. The 4 atypical cases of CNCs showed as strongly contrast enhancement of the tumors with the attachment or infiltrate of the wall of the ventricle than the typical benign cases. These atypical CNCs were in the right lateral ventricle (2 cases), left lateral ventricle (1 case), and third ventricle (1 case). Microscopically, the typical CNCs were well-differentiated tumors with benign histological features. The typical and atypical CNCs were composed of uniform, small to medium-sized cells with rounded nuclei and scant cytoplasm. Immunohistochemically, the typical CNCs were strong in Syn immunopositive (14/14) and neuron-specific enolase (12/14). The atypical CNC tumor cells showed malignant behavior and more positive expression of Ki67 than the benign cases. Surgery is the first choice of treatment, and radiotherapy may be beneficial to postoperative patients.

Central, Extraventricular and Atypical Neurocytomas: a Clinicopathologic Study of 35 Cases from Pakistan Plus a Detailed Review of the Published Literature

BACKGROUND

Central neurocytomas are rare neuronal neoplasms with a favorable prognosis. They are typically located in the lateral ventricles of the brain and mostly histologically correspond to WHO grade II with a Mib 1 labelling index of <2%. Similar tumors located in the cerebral hemispheres and spinal cord, for example, are called "extraventricular neurocytomas". A few tumors histologically show atypia, mitoses, vascular proliferation and/or necrosis and a Mib 1 index >2 % and are designated as "atypical neurocytomas.

AIM

The aim of our study was to describe the common as well as unusual morphologic features and the role of various immunohistochemical stains in the diagnosis of these rare tumors.

MATERIALS AND METHODS

We retrieved and reviewed 35 cases diagnosed between 2001 and 2015.

RESULTS

Sixty percent of patients were males, and the mean age was 26 years. 31 cases (88.6%) were intraventricular and 4(11.4%) were extraventricular. Histologically, 6 cases (17.1%) were compatible with "atypical neurocytomas". All cases showed the classic morphology comprising nests and sheets of uniform, round cells with uniform round to oval nuclei with finely speckled chromatin and perinuclear cytoplasmic clearing (halos). All cases also showed delicate, fibrillary, neuropil-like matrices. Other common histologic features included capillary-sized blood vessels in a branching pattern in 57.1%, foci of calcification in 34.3% and perivascular pseudorosettes in 20%. Rare findings included Homer- Wright or true rosettes in 8.6% and ganglioid cells in 2.9%. Synaptophysin was the most consistent and valuable marker, being positive in almost all cases. GFAP positivity in tumor cells was seen in 25.7% of cases. Follow up was available in 13 patients. Of these 9 had histologically typical and 4 had atypical tumors. Only 1 (with an atypical neurocytoma) died, probably due to complications of surgery within one month, while 12 (including 3 with atypical neurocytomas) remained alive. Recurrence developed in 1 of these 12 patients (histologically consistent with typical morphology) almost 9 years after surgery. Only 4 patients, including 2 with atypical tumors, received postoperative radiotherapy, all with surgery in 2010 or later. Overall, prognosis was excellent with prolonged, recurrence free survival and most patients, even without receiving radiation therapy, were alive and well for many years, even a decade or more after surgery, without developing any recurrence, indicating the benign nature of these neoplasms.

Clinical manifestations of central neurocytoma

Central neurocytomas (CNs) are rare central nervous system tumors that occur in the lateral ventricles. They are prevalent in young adults and are typically benign with excellent prognosis following surgical resection. Because of the rarity of the disease and its similar features with more common tumors, misdiagnosis becomes an issue. Optimal treatment is achieved only when the correct tumor types are distinguished. Typical clinical manifestations include symptoms of increased intracranial pressure, although no clinical feature is pathognomonic to CN. Radiologic imaging, histology, magnetic resonance spectroscopy, and immunohistochemistry must be used to elucidate tumor characteristics and properly diagnose CN.

Neurocytoma of the spinal cord

This article presents an overview of spinal neurocytomas. A rare manifestation of an uncommon tumor, extraventricular neurocytomas (EVNs) should be included in the differential for spinal intradural and intramedullary tumors. Spinal EVNs are generally benign with an indolent pathologic course but may display a variety of acute or chronic clinical behaviors, depending on their anatomic location. Only a handful of spinal EVNs have been described in the literature, often in the form of individual case reports or small case series. Discussion includes a review of the literature and an overview of the clinical, pathologic, and radiologic features of this rare tumor type, as well as the differential diagnosis, treatment options, and general prognosis.

Neurocytoma of the pituitary gland: A case report and literature review

Extraventricular neurocytomas (EVN) are rare central nervous system tumors, often located within the cerebral hemisphere. The present study reports a case of a 56-year-old male patient with bitemporal hemianopsia. Computed tomography and magnetic resonance imaging revealed a tumor in the sellar region. The tumor was totally excised. Postoperative histological examination of the tumor demonstrated that synaptophysin, chromogranin-A and neuron-specific enolase were positive, while luteinizing hormone, follicle-stimulating hormone, growth hormone, prolactin, adrenocorticotropic hormone, thyroid-stimulating hormone, glial fibrillary acidic protein, S-100, nestin and epithelial membrane antigen were negative, which were the main pathological features of neurocytomas. This is the fourth case of EVN located in the sellar region reported. The associated studies are also reviewed.

Treatment strategies for huge central neurocytomas

Central neurocytomas (CNs), initially asymptomatic, sometimes become huge before detection. We described and analyzed the clinical, radiological, operational and outcome data of 13 cases of huge intraventricular CNs, and discussed the treatment strategies in this study. All huge CNs (n=13) in our study were located in bilateral lateral ventricle with diameter ≥5.0 cm and had a broad-based attachment to at least one side of the ventricle wall. All patients received craniotomy to remove the tumor through transcallosal or transcortical approach and CNs were of typical histologic and immunohistochemical features. Adjuvant therapies including conventional radiation therapy (RT) or gamma knife radiosurgery (GKRS) were also performed postoperatively. Transcallosal and transcortical approaches were used in 8 and 5 patients, respectively. Two patients died within one month after operation and 3 patients with gross total resection (GTR) were additionally given a decompressive craniectomy (DC) and/or ventriculoperitoneal shunt (VPS) as the salvage therapy. Six patients received GTR(+RT) and 7 patients received subtotal resection (STR)(+GKRS). Eight patients suffered serious complications such as hydrocephalus, paralysis and seizure after operation, and patients who underwent GTR showed worse functional outcome [less Karnofsky performance scale (KPS) scores] than those having STR(+GKRS) during the follow-up period. The clinical outcome of huge CNs seemed not to be favorable as that described in previous reports. Surgical resection for huge CNs should be meticulously considered to guarantee the maximum safety. Better results were achieved in STR(+GKRS) compared with GTR(+RT) for huge CNs, suggesting that STR(+GKRS) may be a better treatment choice. The recurrent or residual tumor can be treated with GKRS effectively.

Intramedullary neurocytomas in the craniocervical spinal cord: A report of two cases and a literature review

Central neurocytoma is a relatively rare tumor of the central nervous system. Young adults are most commonly affected, with a similar incidence in males and females. The tumor is predominantly occurs in the ventricular system of the brain. The tumor is benign and exhibits a good response to surgical resection and radiation therapy. The typical central neurocytoma occurs in the supratentorial ventricular system in young adults. Extraventricular neurocytomas are rare in the spinal cord. In the present study, two cases of craniocervical neurocytomas and the clinical presentation, magnetic resonance imaging observations, pathological features and two-year follow-up results are reported. The first case presents a 26 year old male with an intramedullary mass extending from the medualla oblongata to the T4 segement of the spine. The second case presents the case of a 48 year old female with an intramedullary mass extending from the oblongata to the T2 segement of the spine. The two patients underwent subtotal resection of the masses and post-operative radiotherapy was administered for three months. Post-operative magentic resoance imaging revealed no tumor recurrence in the two cases, two years after resection. The relevant literature is also discussed.

Central neurocytoma: establishment of the disease entity

The establishment and identification of central neurocytoma as a distinct disease entity are invaluable in catalyzing investigations of neuronal differentiation in central nervous system tumors. The discovery of neuronal differentiation in neuroepithelial tumors has been extended to extraventricular tumors and potentially to various glial tumors undergoing neuronal differentiation. Understanding the disease spectrum of neuronal and mixed neuronal-glial tumors is important for deciphering the mechanism of gliomagenesis.