Posterior cranial fossa gangliogliomas

Infratentorial ganglioglioma mimicking a cerebellar metastasis

We report a case of an infratentorial ganglioglioma in a 56-year-old male, who underwent magnetic resonance imaging (MRI) during the diagnostic workup for a suspected lung cancer. The MRI scan revealed a space-occupying lesion of the left lobulus semilunaris superior cerebelli, which was assumed being a metastasis. The asymptomatic lesion was resected to establish the diagnosis. Histologic and immunohistochemical studies showed a ganglioglioma with World Health Organization grade I characteristics. Although ganglioglioma typically exhibits a supratentorial predilection, it should be included in the differential diagnosis of lesions occurring in the cerebellum.

A Rare Case of Posterior Fossa Tumor and Central Precocious Puberty: Case Presentation and Review of the Literature

Central precocious puberty (CPP) is a condition that causes early gonadotropin-dependent sexual development; CPP is idiopathic in girls in most cases, whereas more than 50% of boys have an identifiable etiology. We conducted a qualitative systematic review following the ENTREQ (enhancing transparency in reporting the synthesis of qualitative research) framework. A search was made in MEDLINE/Pubmed and MeSH Database using the terms "precocious puberty" AND "brain tumor" OR "posterior fossa tumor" OR "cerebellar tumor" OR "infratentorial tumor", identifying five cases of pediatric patients with infratentorial tumors and CPP and a case of cerebellar ganglioglioma without hypothalamic-pituitary-gonadal axis involvement and/or intracranial hypertension. Our work highlights the importance of a multidisciplinary approach and extensive central nervous system imaging for patients presenting with CPP in order to detect possible tumor association. Moreover, we believe that this manuscript could contribute to stimulate other research because the exact mechanism of CPP in infratentorial brain lesions has not been understood yet.

Giant Cerebellar Ganglioglioma Mimicking a Pilocytic Astrocytoma

A benign brain tumor, called a ganglioglioma (GG), can sometimes be found in the cerebrum. We describe an unusual pediatric case of GG in the cerebellum in this article. An 11-year-old male patient had a headache and epilepsy disorder. The head magnetic resonance imaging results revealed a giant cyst with an enhancing mural nodule in the right cerebellar hemisphere that flattened the fourth ventricle. Pilocytic astrocytoma was the provisional diagnosis based on clinical and imaging details. After radical mass eradication, a GG was demonstrated through histopathological analysis. Even though GG is an uncommon tumor, it should be included in the differential diagnosis for a cerebellar mass with both cystic and solid components in children.

Novel TLE4-NTRK2 fusion in a ganglioglioma identified by array-CGH and confirmed by NGS: Potential for a gene targeted therapy

Gangliogliomas are rare neoplasms of the central nervous system that mostly originate in the temporal lobe and are associated with seizures. Literature mentions that BRAF mutations are most commonly associated with gangliogliomas. We discuss a unique case of ganglioglioma originating in the posterior fossa that showed multiple losses and a unique interstitial deletion at 9q21 by an array-comparative genome hybridization (array-CGH). The deletion led to a novel molecular fusion (TLE4-NTRK2) which was confirmed by next generation sequencing and provides a potential for a gene-targeted therapy.

Relative ADC and Location Differ between Posterior Fossa Pilocytic Astrocytomas with and without Gangliocytic Differentiation

BACKGROUND AND PURPOSE

Pilocytic astrocytomas, the most common posterior fossa tumors in children, are characterized by KIAA1549-BRAF fusions and shows excellent 5-year survival rates. Pilocytic astrocytoma with gangliocytic differentiation, a recently defined pilocytic astrocytoma variant that includes glial and neuronal elements similar to a ganglioglioma, may be distinguished from a classic ganglioglioma by molecular, radiologic, and histopathologic features. This study investigated whether imaging could distinguish posterior fossa pilocytic astrocytoma with and without gangliocytic differentiation.

MATERIALS AND METHODS

Preoperative MRIs (± CTs) of 41 children (age range, 7 months to 15 years; mean age, 7.3 ± 3.7 years; 58.5% male) with pilocytic astrocytoma with gangliocytic differentiation (n = 7) or pilocytic astrocytoma (n = 34) were evaluated; differences in tumor location, morphology, and minimum relative ADC between tumor types were compared (Wilcoxon rank sum test, Fisher exact test). Histopathology and BRAF fusion/mutation status were reviewed. Associations of progression-free survival with diagnosis, imaging features, and BRAF status were examined by Cox proportional hazards models.

RESULTS

Pilocytic astrocytoma with gangliocytic differentiation appeared similar to pilocytic astrocytoma but had lower minimum relative ADC (mean, 1.01 ± 0.17 compared with 2.01 ± 0.38 for pilocytic astrocytoma; P = .0005) and was more commonly located within midline structures (P = .0034). BRAF status was similar for both groups. Non-total resection (hazard ratio, 52.64; P = .0002), pilocytic astrocytoma with gangliocytic differentiation diagnosis (hazard ratio, 4.66; P = .0104), and midline involvement (hazard ratio, 3.32; P = .0433) were associated with shorter progression-free survival.

CONCLUSIONS

Minimum relative ADC and tumor location may be useful adjuncts to histopathology in differentiating pilocytic astrocytoma with gangliocytic differentiation from pilocytic astrocytoma. Shorter progression-free survival in pilocytic astrocytoma with gangliocytic differentiation is likely due to a propensity for involvement of midline structures and poor resectability.

Treatment and outcomes for gangliogliomas: a single-center review of 16 patients

Background

Ganglioglioma is a rare and slowly growing benign tumor. We investigated the outcomes of patients who underwent different combination treatments.

Methods

Between 1998 and 2012, 16 patients, including 11 men and 5 women, with a median age of 12.5 years (range, 2.5-65 years) were treated for intracranial gangliogliomas at our institution. The median follow-up period was 5.7 years (range, 48 days-15.6 years). Fifteen cases were included in the outcome assessment because one patient was lost to follow-up. Complete resection was achieved in 8 (53%) patients. Six (40%) patients underwent incomplete resection with or without adjuvant radiotherapy, and one patient with a brainstem tumor underwent only stereotactic biopsy.

Results

Gangliogliomas predominantly affected young (87.5%), male patients and most frequently presented with seizures (64%). Of eight patients who underwent complete resection, seven did not show recurrence, whereas only three of six with incomplete resection showed no recurrence. Four patients with recurrence received salvage treatments (two repeat surgeries and two radiosurgeries). A tumor control rate of 93% (14/15) was achieved at the last follow-up. No recurrence or malignant changes were observed after a median follow-up of 12 and 4.5 years in four patients who received gamma knife (GK) radiosurgery as adjuvant and salvage treatment.

Conclusion

Complete resection produced the best outcomes and incomplete resection followed by adjuvant or salvage treatments showed favorable outcomes. In patients who are not eligible for complete resection because of tumor location or potential neurologic deficits following surgery, GK radiosurgery should be considered for the treatment of residual or recurrent tumors.

Posterior fossa and spinal gangliogliomas form two distinct clinicopathologic and molecular subgroups

Background

Gangliogliomas are low-grade glioneuronal tumors of the central nervous system and the commonest cause of chronic intractable epilepsy. Most gangliogliomas (>70%) arise in the temporal lobe, and infratentorial tumors account for less than 10%. Posterior fossa gangliogliomas can have the features of a classic supratentorial tumor or a pilocytic astrocytoma with focal gangliocytic differentiation, and this observation led to the hypothesis tested in this study - gangliogliomas of the posterior fossa and spinal cord consist of two morphologic types that can be distinguished by specific genetic alterations.

Results

Histological review of 27 pediatric gangliogliomas from the posterior fossa and spinal cord indicated that they could be readily placed into two groups: classic gangliogliomas (group I; n = 16) and tumors that appeared largely as a pilocytic astrocytoma, but with foci of gangliocytic differentiation (group II; n = 11). Detailed radiological review, which was blind to morphologic assignment, identified a triad of features, hemorrhage, midline location, and the presence of cysts or necrosis, that distinguished the two morphological groups with a sensitivity of 91% and specificity of 100%. Molecular genetic analysis revealed BRAF duplication and a KIAA1549-BRAF fusion gene in 82% of group II tumors, but in none of the group I tumors, and a BRAF:p.V600E mutation in 43% of group I tumors, but in none of the group II tumors.

Conclusions

Our study provides support for a classification that would divide infratentorial gangliogliomas into two categories, (classic) gangliogliomas and pilocytic astrocytomas with gangliocytic differentiation, which have distinct morphological, radiological, and molecular characteristics.

Brainstem gangliogliomas: a retrospective series

OBJECT

The authors retrospectively analyzed data on brainstem gangliogliomas treated in their department and reviewed the pertinent literature to foster understanding of the preoperative characteristics, management, and clinical outcomes of this disease.

METHODS

In 2006, the authors established a database of treated lesions of the posterior fossa. The epidemiology findings, clinical presentations, radiological investigations, pathological diagnoses, management, and prognosis for brainstem gangliogliomas were retrospectively analyzed.

RESULTS

Between 2006 and 2012, 7 patients suffering from brainstem ganglioglioma were treated at the West China Hospital of Sichuan University. The mean age of the patients, mean duration of symptoms prior to diagnosis, and mean duration of follow-up were 28.6 years, 19.4 months, and 38.1 months, respectively. The main presentations were progressive cranial nerve deficits and cerebellar signs. Subtotal resection was achieved in 2 patients, and partial resection in 5. All tumors were pathologically diagnosed as WHO Grade I or II ganglioglioma. Radiotherapy and adjuvant chemotherapy were not administered. After 21-69 months of follow-up, patient symptoms were resolved or stable without aggravation, and MRI showed that the size of residual lesions was unchanged without progression or recurrence.

CONCLUSIONS

The diagnosis of brainstem ganglioglioma is of great importance given its favorable prognosis. The authors recommend the maximal safe resection followed by close observation without adjuvant therapy as the optimal treatment for this disease.

Hemorrhagic ganglioglioma of the posterior fossa: case report

Gangliogliomas are rare tumors of the central nervous system that are usually found in the supratentorial compartment, although cases throughout the nervous system have been described. They are generally low-grade malignancies that are amenable to cure by surgical resection. Most manifest as seizures, though, based on location, they can present with focal neurological deficits. We present here a rare case of an infratentorial ganglioglioma presenting with hemorrhage. To our knowledge this is the only reported case of a hemorrhagic ganglioglioma and, as such, we examine its possible prognosis.

Cerebellar ganglioglioma

The cerebellar location of ganglioglioma (GG) is exceptional. We report one case of a 27-year-old man who underwent an intracranial hypertension syndrome and a static cerebellar syndrome. Brain magnetic resonance images revealed a cyst image in the vermis. Histological study after surgical removal, revealed a ganglioglioma tumor. Through this case and literature review, the authors discuss some epidemiological, histological, clinical, radiological and management features of this very rare tumor.