Pediatric primary anaplastic ganglioglioma: a case report and review of the literature

Imaging of pediatric glioneuronal and neuronal tumors

Glioneuronal tumors (GNTs) are an expanding group of primary CNS neoplasms, commonly affecting children, adolescents and young adults. Most GNTs are relatively indolent, low-grade, WHO grade I lesions. In the pediatric age group, GNTs have their epicenter in the cerebral cortex and present with seizures. Alterations in the mitogen-activated protein kinase (MAPK) pathway, which regulates cell growth, are implicated in tumorigenesis. Imaging not only plays a key role in the characterization and pre-surgical evaluation of GNTs but is also crucial role in follow-up, especially with the increasing use of targeted inhibitors and immunotherapies. In this chapter, we review the clinical and imaging perspectives of common pediatric GNTs.

High-Grade Temporal Ganglioglioma in an Older Adult Woman

Ganglioglioma (GG) is a WHO-grade 1 glioneuronal neoplasm. It is well differentiated with a slow-growing pattern and is composed of a combination of neoplastic ganglion and glial cells. Anaplastic ganglioglioma (AGG) is an extremely rare malignant variant of ganglioglioma, which is not included in the new WHO classification; however, the term is used to talk about gangliogliomas with data of malignancy. AGGs usually occur in children and young adults and are associated with high recurrence and mortality. The authors describe the case of a 62-year-old woman with AGG. She presented with cacosmia, vertigo, nausea, and focal-onset seizures with secondary generalization. Magnetic resonance imaging (MRI) revealed an intra-axial lesion in the left temporal lobe. She underwent microsurgical resection guided by electrocorticography (ECoG), and a diagnosis of AGG based on microscopic morphology and immunohistochemical analysis was obtained. She was discharged a few days after surgery with subtotal resection of the lesion, no additional neurological deficit, and adequate seizure control. AGG is a very rare and poorly studied entity. It is currently a controversial term used to refer to gangliogliomas with signs of malignancy. It occurs mainly in children and young adults with temporal lobe epilepsy. Total resection is the best prognostic factor, given the unknown efficacy of radiotherapy and chemotherapy. In our case, the patient was an adult woman with a subtotal resection followed by concomitant radiotherapy and chemotherapy, obtaining a mean survival similar to that reported in the literature, so it can be thought that there is a benefit obtained with chemotherapy and radiotherapy despite having performed a subtotal resection of the lesion. Further studies are needed to establish clear diagnostic criteria for AGG, and a multicenter database of AGGs is necessary for a better understanding of the pathology and to offer the best treatment and prognosis.

Impact of surgery, adjuvant treatment, and other prognostic factors in the management of anaplastic ganglioglioma

BACKGROUND/PURPOSE

Anaplastic ganglioglioma (AGG) is a rare tumor with both glial and neuronal component accounting for less than 1% of all CNS tumors with limited information about the optimum treatment and outcome of these tumors.

METHOD AND MATERIALS

We did a thorough search of the PubMed with the following MesH terms: "Ganglioglioma; Anaplastic ganglioglioma; Ganglioglioma AND treatment; and Anaplastic ganglioglioma AND survival" to find all possible publications related to AGG to perform an individual patient data analysis and derive the survival outcome and optimum treatment of these tumors.

RESULTS

A total of 56 articles were retrieved pertaining to AGG with 88 patients. However, a total of 40 publications found eligible with 69 patients for individual patient data analysis. Median age for the entire cohort was 16 years (range 0.2-77 years). Surgical details were available for 64 patients. A gross total or near total resection was reported in 21 cases (32.8%), subtotal resection or debulking was reported in 25 cases (39.1%). Surgical details were available for 64 patients. A gross total or near total resection was reported in 21 cases (32.8%), and subtotal resection or debulking was reported in 25 cases (39.1%). Median overall survival (OS) was 29 months [95% CI 15.8-42.2 months] with 2- and 5-year OS 61 and 39.4% respectively.

CONCLUSION

AGG is associated with a dismal. Pediatric age and a gross total resection of tumor confer a better progression-free survival and OS. Hence, surgery should remain the cornerstone of therapy. However, because of modest survival, there is enough opportunity to improve survival with addition of adjuvant radiation and chemotherapy. A whole genome sequencing and molecular characterization would help to derive the best treatment option.

Pediatric intracranial primary anaplastic ganglioglioma

BACKGROUND

Primary intracranial anaplastic gangliogliomas are rare tumors in the pediatric patient group. Most of them present with symptoms of elevated pressure or symptomatic epilepsy. Extraaxial location is far more common than axial location. On MRI examination, they mimic pilocytic astrocytomas. The outcome after surgery depends mainly on the possible amount of surgical resection, and oncological therapy is necessary to prevent recurrence of the disease.

CASE REPORT

An 11-year-old boy presented with headache and double vision due to obstructive hydrocephalus. MRI of the brain revealed an axial partially contrast enhancing lesion in the quadrigeminal plate extending from the cerebellum to the pineal gland and causing hydrocephalus. Subtotal removal of the lesion was performed, and the diagnosis of an anaplastic ganglioglioma was established and confirmed by the reference center. At the latest follow up (3 months), the boy is without any neurological symptoms and scheduled for radiation therapy as well as chemotherapy.

Facial spasms, but not hemifacial spasm: a case report and review of literature

INTRODUCTION

Facial spasms represent a complicated array of neurological motor disorders with unique diagnostic and treatment algorithms. Due to the rarity of many of these disorders in the pediatric population, special care must be taken in identifying subtle differences in presentation of these disorders.

METHODS

We present a case of a 3-year-old boy diagnosed with a brainstem ganglioglioma, Chiari 1 malformation, and a 2-year history of left-sided facial spasms. Stereotyped facial contractions and subtle eye deviation occurred every 10 s, with downward movement rather than upward elevation of the eyebrow.

RESULTS

MRI revealed absence of a clear compressive vessel of the centrally-myelinized portion of the facial nerve, and EMG of the left facial nerve demonstrated no abnormal motor response or evidence of "lateral spread." Given these findings, a diagnosis of hemifacial seizures was made. Microvascular decompression was not recommended, and botulinum toxin injection was not pursued; however, the patient has remained refractory to antiepileptic drugs, possibly due to biochemical alteration by his ganglioglioma. He may eventually require surgical debulking should his symptoms progress.

CONCLUSION

Hemifacial spasm is a well-recognized disorder, but similar conditions can, at times, imitate its appearance. While our patient presented with facial spasms, his clinical history, examination, and radiographic and electrophysiological findings were more consistent with hemifacial seizures secondary to a brainstem lesion, rather than hemifacial spasms. It is important to distinguish the two entities, as misdiagnosis and inappropriate diagnostic or therapeutic measures may be taken inadvertently.

Rare glial tumors

This chapter describes the epidemiology, pathology, molecular characteristics, clinical and neuroimaging features, treatment, outcome, and prognostic factors of the rare glial tumors. This category includes subependymal giant cell astrocytoma, pleomorphic xanthoastrocytoma, astroblastoma, chordoid glioma of the third ventricle, angiocentric glioma, ganglioglioma, desmoplastic infantile astrocytoma and ganglioma, dysembryoplastic neuroepithelial tumor, papillary glioneuronal tumor, and rosette-forming glioneuronal tumor of the fourth ventricle. Many of these tumors, in particular glioneuronal tumors, prevail in children and young adults, are characterized by pharmacoresistant seizures, and have an indolent course, and long survival following surgical resection. Radiotherapy and chemotherapy are reserved for recurrent and/or aggressive forms. New molecular alterations are increasingly recognized.

Anaplastic ganglioglioma: a report of three cases and review of the literature

Gangliogliomas are rare tumors of the central nervous system that are thought to arise from a glioneuronal precursor and consist of both neuronal and glial elements. Grade III, or anaplastic ganglioglioma (AGG), most commonly affects children and young adults, generally arises in a supratentorial location, is highly epileptogenic, and often results in diffuse local and distant failure within the craniospinal axis. Pathologically, these tumors are graded by the degree of malignancy in their glial portion and radiologic diagnosis is difficult due to the wide variation in its degree of solid and cystic components, contrast uptake, and calcification patterns. This report presents three cases of AGG, with initial treatment including subtotal resection followed by conformal radiotherapy. In the case where the AGG developed in the setting of an existent low-grade astrocytoma, the patient received no chemotherapy. Both of the other de novo cases were managed with adjuvant chemoradiotherapy with temozolomide. Recurrence occurred at 6, 16, and 20 months following therapy. Two of the three patients experienced symptomatic decline at recurrence, but experienced Karnofsky performance status (KPS) improvement after salvage therapy, including the reduction of cranial neuropathy and balance. All patients had a significant reduction in presenting symptoms following salvage therapy. Patients died at 23, 20, and 22 months following initial surgical management, respectively. A review of anaplastic and malignant gangliogliomas is presented in the context of these three cases.

Mutant BRAF V600E protein in ganglioglioma is predominantly expressed by neuronal tumor cells

Ganglioglioma is a rare CNS tumor with a benign biological behavior. Recently, the BRAF V600E mutation was identified in approximately 20 % of gangliogliomas. Here, we analyzed a total of 71 gangliogliomas for BRAF V600E mutational status by VE1 immunohistochemistry and direct DNA sequencing. The BRAF V600E mutation was detected in 41/71 (58 %) gangliogliomas by immunohistochemistry. DNA sequencing was concordant in 60 of 62 analyzed cases. BRAF status was compared with clinical, histological and immunohistochemical data. Presence of the BRAF V600E mutation was associated with expression of synaptophysin in the tumor (p = 0.0008), presence of dysplastic neurons (p = 0.011) and lymphocytic cuffs (p = 0.018), and with younger age (p = 0.0054). Extensive hemosiderin deposition within the tumor was significantly associated with BRAF wild-type status (p = 0.042). No significant association was found with proliferation (p = 0.053), presence of phospho ERK (p = 0.1) or senescence marker p16(INK4a) (p = 0.22). Using VE1, we localized the BRAF V600E-mutated protein predominantly to the neuronal compartment, indicating that BRAF mutations occur in cells that have the capacity to differentiate into ganglionic cells. In many cases mutant BRAF is additionally expressed by the glial compartment, indicating that in these cases the cell targeted by BRAF mutation was likely capable of differentiating along both the ganglionic and glial lineages. No cases with an exclusive expression of BRAF V600E in the glial compartment were observed. Thus, using VE1 we identified the neuronal compartment as an essential part of this mixed glioneuronal tumor.