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.

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.

Rare pediatric central neurocytomas.

Central neurocytoma is extremely rare in pediatrics. In a single institute's record, it represents about 0.2% of brain tumors in children. The treatment of central neurocytoma in children is not different from that for adult patients. Surgical resection is the mainstay of treatment. After complete resection, the long-term prognosis is excellent. Adjuvant radiation therapy or radiosurgery may be applied to residual or recurrent tumors. However, the exact indication for each modality should be refined by accumulation of clinical data for this rare disease in children.

Secondary normal pressure hydrocephalus in a patient with isolated frontal dilatation--an insight into pathophysiology?

Current theories of the pathophysiology of normal pressure hydrocephalus suggest the classical symptoms are a consequence of disruption of normal frontal function. We present the case of a 70-year-old patient with an isolated, frontal dilatation of his lateral ventricles in the presence of a complete triad as supportive of these theories.

Emotion and cognitive function assessment of patients with central neurocytoma resection through transcortical frontal approach: a 5-year postoperative follow-up study.

BACKGROUND: Central neurocytoma accounts for 0.1% of primary brain tumor that often occurs in young adults. Surgery is the main treatment for central neurocytoma and the rate of 5-year survival reaches up to over 90%. This study aimed to assess the effect of transcortical frontal approach to surgical resection of central neurocytoma on emotion and cognitive function 5 years after surgery. METHODS: Telephone following-up visits were used in this study. By means of neuropsychological testing, assayed emotion, memory and abstract thinking ability of 18 patients undergoing central neurocytoma resection by transcortical frontal approach for 5 years or more, with another 21 normal cases as control group were enrolled. The data were analyzed statistically by paired t test with SPSS11.5. RESULTS: Patients whose central neurocytoma was removed by transcortical frontal approach were not affected on calculating ability 5 years after operation while ability of memory declined sharply (P = 0.000), the older, the more sharply (P = 0.036). Ability of abstract thinking was significantly reduced (P = 0.000), the older, the more significantly as well (P = 0.012); additionally, anxiety and depression occurred in patients rather more than those of control group (P = 0.000), especially cognitive impairment. CONCLUSIONS: Transcortical frontal approach for surgical resection of central neurocytoma has certain long-term influence on patients' life quality, vulnerable to anxiety, depression and cognitive impairment, the severity of which was correlated to age. Therefore, improving surgical approach will be of value for better long-term life quality of patients.

Gamma knife radiosurgery for central neurocytomas.

The long-term outcome of gamma knife radiosurgery (GKS) for central neurocytomas remains unclear. In the present study, we retrospectively reviewed the medical records of 7 patients with 8 central neurocytomas who underwent GKS between March 1997 and April 2007. They were 3 men and 4 women age ranging 9 to 53 years old (mean 32.5 years old). The tumor volume at the time of GKS was 0.34-6.10 cm(3) (mean 3.86 cm(3)). All patients had undergone 1 to 3 incomplete surgical resections (mean 1.75) before GKS, the surgical specimen being evaluated histologically and immunohistochemically. The follow-up period after GKS was 15 to 136 months (mean 63.6 months). The tumors were treated with a marginal dose of 12-18 Gy (mean 13.9 Gy). Only one of the seven patients died of tumor recurrence and intracranial hemorrhage 40 months after GKS. The other tumors remained progression-free. The control rate of the tumor growth was 7/8. Although histological malignant transformation is rare, the postoperative course of this tumor is not always good, showing tumor progression, intracranial hemorrhage, or craniospinal dissemination. Therefore, we recommend GKS for residual or recurrent tumors especially at early detection before tumor progression.

Neurocytoma of the spinal cord: report of three cases and review of the literature.

The spinal cord is a very rare location for extra-ventricular neurocytomas. Composed of small round cells with neuronal differentiation, neurocytoma has a particularly favourable prognosis. Long disease-free intervals have been observed in patients who received sub-total removal and radiotherapy. A careful intra-operative frozen section examination is helpful in avoiding excessive surgical tissue disturbance and to identify the best treatment option. To date, eight cases of neurocytoma of the spinal cord have been described. We report three more patients; one with very long survival, and review the published literature for this condition.

Coincidence of central neurocytoma and multiple glioblastomas: a rare case report.

Coincidence of parenchymal primary brain tumors of different histogenesis is extremely rare. To the best of our knowledge, the present case of simultaneous appearance of a central neurocytoma and multiple glioblastomas is the first to be reported. Multiple intraaxial brain neoplasms were disclosed in a 39-year-old man and were surgically resected. Histological diagnosis of the tumor located in the right lateral ventricle was central neurocytoma whereas two tumors of the left temporal lobe were glioblastomas. The latter were located in close proximity to the subarachnoid space, had atypical radiological appearance, and were slightly positive for synaptophysin and neurofilament protein. It can be speculated that both malignant neoplasms were, in fact, dedifferentiated central neurocytoma, which developed from distant tumor deposits. This case seems to be in agreement with the hypothesis that central neurocytoma arises from the progenitor cells with potential for both neuronal and glial differentiation. Better understanding of histogenesis of this tumor is definitely needed.

Short communication: conformal therapy for peri-ventricular brain tumors: is target volume deformation an issue?

Physiologic variations in ventricular volumes could have important implications for treating patients with peri-ventricular brain tumors, yet no data exist in the literature addressing this issue. Daily megavoltage computed tomography (CT) scans in a patient with neurocytoma receiving fractionated radiation revealed minimal changes, suggesting that margins accounting for ventricular deformation are not necessary.

A case of extraventricular neurocytoma of the spinal cord.

Central neurocytoma is a rare neuroectodermal tumor generally found in young adults. It mainly originates from lateral ventricles. Extraventricular location of this kind of tumor, especially spinal cord involvement, is extremely rare. This article is the ninth case of central neurocytoma derived from the spinal region, and includes a review of the literature. The patient in this case is a 49-year-old woman presenting with C3-C5 spinal mass with typical histopathologic findings and low MIB-1 index.

Central neurocytoma: a clinico-pathological study of eight cases.

Central neurocytomas are benign neuronal tumours generally found in the lateral or third ventricles. They are rare, comprising < 1% of all brain tumours. It is frequently confused with other tumours of the central nervous system particularly oligodendroglioma. The present study was done to analyse the histopathological features including immunohistochemical profile of these rare tumours. Eight cases were taken up for the study. Seven of the cases had an intraventricular location and one was located outside the ventricles. Increased intracranial pressure was the most common presenting symptom. Microscopically all tumours were composed of small uniform cells with perinuclear halos and regular round nuclei. The tumour in extraventricular location showed atypical features. Immunohistochemistry showed positivity for neuronal markers. The present series highlights the characteristic clinical and pathological findings of this rare brain tumour. Immunostaining for neuronal markers are essential for distinguishing them from other small round cell tumours of the brain.

Mixed glioneuronal tumour of the fourth ventricle with prominent rosette formation.

We describe three unusual tumours characterized by a mixture of glial and neuronal differentiation, involvement of the posterior fossa and formation of rosettes. Mixed glial-neuronal tumours of the posterior fossa are rare and poorly described neoplasms. However, several distinctive entities have appeared in the literature over recent years under a variety of different names. Our cases demonstrate the morphological features of the 'rosette-forming glioneuronal tumour of the fourth ventricle', a recently identified tumour characterised by its unique location, neurocytic pseudo-rosette formation and the presence of a low grade astrocytoma component. The long term prognosis of these tumours remains unclear. However, the clinical data available including the cases presented here, along with the histological features, suggest that these are low grade tumours with a good prognosis after surgical resection.

Extraventricular neurocytoma presenting with intratumoral hemorrhage.

A case of extraventricular neurocytoma with spontaneous intratumoral hemorrhage is reported. A 47-year-old man presented with sudden left-sided hemiparesis. Magnetic resonance imaging revealed a right parietal subcortical mass with intratumoral hemorrhagic transformation and without contact to the ventricular system. After complete microsurgical removal, the tumor was histologically diagnosed as neurocytoma. Usually, the term "central neurocytoma" is restricted to neurocytic neoplasms arising within the cerebral ventricles. In the majority of the cases, these slow-growing, generally circumscribed lesions become symptomatic by obstructive hydrocephalus. Hemorrhagic onset is sporadically reported in the literature. In contrast to central neurocytomas, neurocytic lesions located within the brain parenchyma, so-called "extraventricular neurocytomas" are very uncommon. To the knowledge of the authors, this is the first case of an extraventricular neurocytoma with histological classic features presenting with intratumoral hemorrhage in adults.

Cerebral neurocytoma without ganglion cell differentiation.

Neurocytomas are rare neuronal tumours, and are defined as tumours comprising cells with neuronal differentiation; they commonly arise in the ventricles. We report a case of a cerebral neurocytoma in a young man who presented with hemiparesis. The tumour was a radiologically a well-circumscribed large cyst with solid mass; the histopathology showed a well-differentiated lesion comprising uniform, round cells with perinuclear halos in a neuropil background, and immunohistochemically positive for neuronal markers (synaptophysin, neuron-specific enolase and neurofilaments). We suggest that cerebral neurocytomas should be considered among the uncommon causes of a large intra-axial cystic mass with a solid component in young adults.