Intraventricular ganglioglioma: a short illustrated review

Nomograms Based on MRI Radiomics for Differential Diagnosis and Predicting BRAFV600E Expression in Pleomorphic Xanthoastrocytoma and Ganglioglioma

RATIONALE AND OBJECTIVES

This study was designed to investigate the value of nomograms based on MRI radiomics and clinical semantic features in identifying pleomorphic xanthoastrocytoma (PXA) and ganglioglioma (GG) as well as predicting BRAFV600E expression.

MATERIALS AND METHODS

This study included 265 patients histologically diagnosed with PXA (n = 113) and GG (n = 152). T1WI, T2WI, and CET1 sequences were utilized to extract radiomics features. Univariate analysis, Spearman correlation analysis, and the least absolute shrinkage and selection operator were used for dimensionality reduction and feature selection. Following this, logistic regression was utilized to establish the radiomics model. Univariate and multivariate analyses of clinical semantic features were applied, and clinical models were constructed. The nomograms were established by merging radiomics and clinical features. Furthermore, ROC curve analysis was used for examining the model performance, whereas the decision curve analysis (DCA) examined the clinical utility of the nomograms.

RESULTS

Nomograms achieved the best predictive efficacy compared to clinical and radiomics models alone. Concerning the differentiation between PXA and GG, the area under the curve (AUC) values of the nomogram were 0.879 (0.828-0.930) and 0.887 (0.805-0.969) for the training and testing cohorts, respectively. For predicting BRAFV600E expression, the AUC values of the nomogram were 0.873 (0.811-0.936) and 0.851 (0.740-0.963) for the training and testing cohorts, respectively. DCA confirmed the clinical utility of the nomograms.

CONCLUSION

Nomograms based on radiomics and clinical semantic features were noninvasive tools for differential diagnosis of PXA and GG and predicting BRAFV600E expression, which may be helpful for assessing patient prognosis and developing individualized treatment strategies.

Diagnosis and Therapeutic Management of Ventricular Gangliogliomas: An Illustrated Review

BACKGROUND

Gangliogliomas (GGs) are extremely rare benign neoplasms frequently located within the temporal lobe that usually present with seizures. GGs growing predominantly within the ventricular system (VGGs) are even more infrequent, so definite conclusions concerning their diagnosis and therapeutic management are lacking.

METHODS

A retrospective review of case reports of VGGs was performed from the introduction of modern imaging techniques, including 4 new illustrative cases treated in our department.

RESULTS

Thirty-four cases were collected. Ages ranged from 10 to 71 years (mean, 26.62 years), and 55.9% were male. Most patients developed symptoms related to high intracranial pressure. The lateral ventricles were predominantly involved (58.8%). Obstructive hydrocephalus was observed in 54.5% of patients. Cystic degeneration and calcification were frequently observed. Surgical treatment was carried out in all cases. Morbidity and mortality were 17.6% and 2.9%, respectively. Gross total tumor resection was achieved in 64.5% of patients. Four patients experienced tumor dissemination along the neural axis. More than 90% of patients maintained a good functional status at last follow-up.

CONCLUSIONS

Despite their low incidence, a diagnosis of VGGs should be considered in young male adults who progressively develop intracranial hypertension, caused by a ventricular mass showing signs of cystic degeneration and calcification. Maximal and safe surgical resection represents the gold standard for the treatment of symptomatic VGGs, although total removal is frequently precluded by difficulties in defining appropriate tumor boundaries. Adjuvant radiotherapy should be considered if an incomplete resection was carried out, especially in World Health Organization grade III neoplasms.

Glioneuronal Tumor With Features of Ganglioglioma and Neurocytoma Arising in the Fourth Ventricle: A Report of 2 Unusual Cases and a Review of Infratentorial Gangliogliomas

Infratentorial glioneuronal neoplasms are overall quite rare and are more commonly low-grade with surgical excision usually being curative. Multiple distinct histologic entities have been described including rosette-forming glioneuronal tumor, papillary glioneuronal tumor, neurocytoma, dysplastic gangliocytoma of the cerebellum (Lhermitte-Duclos disease), cerebellar liponeurocytoma, and ganglioglioma. While each of these entities has distinct findings, in some instances a tumor may demonstrate overlapping histologic features with mixed components. Herein, we report 2 unusual adult cases of a fourth ventricular glioneuronal tumor with features of ganglioglioma and neurocytoma, with one coming from a surgical resection and one found incidentally at autopsy. To the best of our knowledge, this specific histologic combination has not previously been described. As such, the clinical significance is unknown although in both cases the neoplasms were circumscribed and appeared to be low grade. The presence of the gangliogliomatous component was of particular interest since these are extremely rare occurrences in the fourth ventricle and we provide a comprehensive review of infratentorial gangliogliomas.

Ganglioglioma Arising from the Septum Pellucidum: Case Report and Review of the Literature

BACKGROUND

Gangliogliomas are low-grade neoplasms that typically affect patients under the age of 30 and present with epilepsy and symptoms of mass effect. Here, we report a case of an intraventricular ganglioglioma involving the septum pellucidum in a pediatric patient with history of optic glioma. Only one other pediatric intraventricular ganglioglioma arising from the septum pellucidum has been reported previously.

CASE REPORT

The patient initially presented at 9 months of age with a pilocytic astrocytoma centered on the optic chiasm, treated with chemotherapy and radiation at 3 years of age. Routine follow-up imaging at 13 years of age revealed the development of a mass in the septum pellucidum, which was subtotally resected endoscopically because of its proximity to the fornices. Pathology confirmed a ganglioglioma positive for the BRAF V600E mutation. The tumor residual progressed and was treated with stereotactic radiosurgery. The patient was asymptomatic at her 6-month follow-up visit and the size of the nodule remained stable.

LITERATURE REVIEW

Our review of the 25 previously reported intraventricular gangliogliomas found that their pre-surgical diagnoses were often incorrect, reflecting the difficulty of making the diagnosis with signs, symptoms, and imaging alone. Patients can be reassured that the prognosis is generally favorable following uncomplicated neurosurgical resection.

Natural course and prognosis of anaplastic gangliogliomas: a multicenter retrospective study of 43 cases from the French Brain Tumor Database

Background

Anaplastic gangliogliomas (GGGs) are rare tumors whose natural history is poorly documented. We aimed to define their clinical and imaging features and to identify prognostic factors.

Methods

Consecutive cases of anaplastic GGGs in adults prospectively entered into the French Brain Tumor Database between March 2004 and April 2014 were screened. After diagnosis was confirmed by pathological review, clinical, imaging, therapeutic, and outcome data were collected retrospectively.

Results

Forty-three patients with anaplastic GGG (median age, 49.4 y) from 18 centers were included. Presenting symptoms were neurological deficit (37.2%), epileptic seizure (37.2%), or increased intracranial pressure (25.6%). Typical imaging findings were unifocal location (94.7%), contrast enhancement (88.1%), central necrosis (43.2%), and mass effect (47.6%). Therapeutic strategy included surgical resection (95.3%), adjuvant radiochemotherapy (48.8%), or radiotherapy alone (27.9%). Median progression-free survival (PFS) and overall survival (OS) were 8.0 and 24.7 months, respectively. Three- and 5-year tumor recurrence rates were 69% and 100%, respectively. The 5-year survival rate was 24.9%. Considering unadjusted significant prognostic factors, tumor midline crossing and frontal location were associated with shorter OS. Temporal and parietal locations were associated with longer and shorter PFS, respectively. None of these factors remained statistically significant in multivariate analysis.

Conclusions

We report a large series providing clinical, imaging, therapeutic, and prognostic features of adult patients treated for an intracerebral anaplastic GGG. Our results show that pathological diagnosis is difficult, that survivals are only slightly better than for glioblastomas, and that complete surgical resection followed with adjuvant chemoradiotherapy offers longer survival.

Ganglioglioma in the Third Ventricle: A Case Report and Literature Review

Gangliogliomas typically arise in the cerebral hemispheres, but may occur rarely in the ventricles. Herein, we report a 38-year-old woman who was treated for hydrocephalus caused by a ganglioglioma of the third ventricle. Magnetic resonance imaging (MRI) revealed a heterogeneously enhanced tumor occupying the anterior part of the third ventricle. A left trans-lateral ventricular trans-foramen of Monroi approach was effective in achieving subtotal resection of the tumor, which had arisen from the medial part of left thalamus to the hypothalamus. Follow-up MRI showed no recurrence of the tumor 5-years after surgery. On pathological examination, the tumor was composed of a glial component that presented features mimicking pilocytic astrocytoma with proliferations of large gangliocytic cells that stained positive for neuronal markers. A review of six similar cases in the literature, including our own, revealed hydrocephalus to be the main symptom of gangliogliomas, with pituitary insufficiencies and visual disturbances having also been reported. In conclusion, we highlight the importance of gangliogliomas in the differential diagnosis of third ventricular tumors presenting with hydrocephalus.

RNaseH2A is involved in human gliomagenesis through the regulation of cell proliferation and apoptosis

Mutations in the RNaseH2A gene are involved in Aicardi‑Goutieres syndrome, an autosomal recessive neurological dysfunction; however, studies assessing RNaseH2A in relation to glioma are scarce. This study aimed to assess the role of RNaseH2A in glioma and to unveil the underlying mechanisms. RNaseH2A was silenced in glioblastoma cell lines U87 and U251. Gene expression was assessed in the cells transfected with RNaseH2A shRNA or scramble shRNA by microarrays, validated by quantitative real time PCR. Protein expression was evaluated by western blot analysis. Cell proliferation was assessed by the MTT assay; cell cycle distribution and apoptosis were analyzed by flow cytometry. Finally, the effects of RNaseH2A on colony formation and tumorigenicity were assessed in vitro and in a mouse xenograft model, respectively. RNaseH2A was successively knocked down in U87 and U251 cells. Notably, RNaseH2A silencing resulted in impaired cell proliferation, with 70.7 and 57.8% reduction in the U87 and U251 cells, respectively, with the cell cycle being blocked in the G0/G1 phase in vitro. Meanwhile, clone formation was significantly reduced by RNaseH2A knockdown, which also increased cell apoptosis by approximately 4.5-fold. In nude mice, tumor size was significantly decreased after RNaseH2A knockdown: 219.29±246.43 vs. 1160.26±222.61 mm3 for the control group; similar findings were obtained for tumor weight (0.261±0.245 and 1.127±0.232 g) in the shRNA and control groups, respectively). In the microarray data, RNaseH2A was shown to modulate several signaling pathways responsible for cell proliferation and apoptosis, such as IL-6 and FAS pathways. RNaseH2A may be involved in human gliomagenesis, likely by regulating signaling pathways responsible for cell proliferation and apoptosis.

Hemifacial Spasm in a Child Treated With Microvascular Decompression of the Facial Nerve

BACKGROUND

Hemifacial spasm is a rare condition in children that is characterized by involuntary contractions of muscles innervated by the ipsilateral facial nerve.

PATIENT DESCRIPTION

We describe a 6-year-old girl who presented with intermittent involuntary spasms of the right face. Magnetic resonance imaging demostrated a loop of the anterior inferior cerebral artery contacting and elevating the cisternal segment of the right facial nerve; this finding was confirmed at surgery where microvascular decompression of the facial nerve was performed without complication. Following surgery she had immediate remission of symptoms, but the hemifacial spasms slowly recurred within 8 months of surgery only to resolve by age 11 years.

CONCLUSION

This is the youngest patient reported with hemifacial spasms related to a vascular etiology, which initially responded to surgical treatment. The authors review this syndrome in children and discuss possible etiologies and management options.

Intraventricular ganglioglioma prognosis and hydrocephalus: the largest case series and systematic literature review

BACKGROUND

Ganglioglioma is mostly found in cerebral parenchymal, and it is rarely located in the ventricular system. To date, ganglioglioma within the ventricular system has been reported in only 10 cases. Its prognosis and relationship with complicating hydrocephalus are unclear.

METHODS

A total of 7 cases with intraventricular ganglioglioma diagnosed by the surgical pathology examination from June 2004 to April 2011 in our center were retrospectively analyzed. The clinical data were collected from the clinical medical records, and the tumor site, size and basement of tumor were analyzed. Follow up was performed to obtain the clinical outcomes.

RESULTS

The 7 cases included 5 males and 2 females, with disease onset at 23.6 ± 14.9 years old. Epilepsy as the initial symptom was observed in 1 case. Reduced hearing, dizziness and weakness of both lower limbs were found in 1 case. Intracranial hypertension were detected in 5 cases, including 1 case complicating by decreased visual acuity. Tumors were located in the lateral ventricle in 5 cases, while 2 cases in the third ventricle. Hydrocephalus was observed in 5 cases, including 2 cases with severe hydrocephalus, and both underwent ventriculoperitoneal shunting. Total resection of tumors was performed in 5 cases, and 2 cases underwent gross total resection. The mean duration of follow-up was 28.7 months (8-90 months). Intracranial hypertension in all cases disappeared. Even radiotherapy post-surgery, one case with GTR relapsed 1 year later. However, the other 6 cases didn't relapse.

CONCLUSIONS

Ganglioglioma in ventricular system is extremely rare, mainly with the symptoms of intracranial hypertension or seizure. The degree of hydrocephalus is closely related to the site of tumor's basement. The prognosis is good after total resection. The patients with GTR should be followed-up.

Gangliogliomas: recent advances in classification and treatment

Gangliogliomas are uncommon neoplasms of the CNS and, as a consequence, few randomized, clinical trials have been performed, thereby limiting treatment guidelines. The best management of newly diagnosed gangliogliomas entails a complete resection, corroborated by postoperative contrast-enhanced MRI. If an incomplete resection is documented, a second attempt at gross total resection should be considered, given the prognostic significance of complete resection. Small-volume residual disease is best managed with involved-field radiotherapy. The role of chemotherapy is uncertain and, in general, would be reserved for patients having previously failed surgery and radiotherapy. This article summarizes the most important available up-to-date information on clinical, prognostic, radiological, pathological and therapeutic findings for gangliogliomas in order to provide valuable guidance for the diagnosis and management of such uncommon tumors. This information may be considered as possible background for future studies designed to clarify the complex management of these tumors.