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

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.

Behavioral Improvements following Lesion Resection for Pediatric Epilepsy: Pediatric Psychosurgery?

INTRODUCTION

Resection of brain lesions associated with refractory epilepsy to achieve seizure control is well accepted. However, concurrent behavioral effects of these lesions such as changes in mood, personality, and cognition and the effects of surgery on behavior have not been well characterized. We describe 5 such children with epileptogenic lesions and significant behavioral abnormalities which improved after surgery.

CASE DESCRIPTIONS

Five children (ages 3-14 years) with major behavioral abnormalities and lesional epilepsy were identified and treated at our center. Behavioral problems included academic impairment, impulsivity, self-injurious behavior, and decreased social interaction with diagnoses of ADHD, oppositional defiant disorder, and autism. Pre-operative neuropsychiatric testing was performed in 4/5 patients and revealed low-average cognitive and intellectual abilities for their age, attentional difficulties, and poor memory. Lesions were located in the temporal (2 gangliogliomas, 1 JPA, 1 cavernoma) and parietal (1 DNET) lobes. Gross total resection was achieved in all cases. At mean 1-year follow-up, seizure freedom (Engel 1a in 3 patients, Engel 1c in 2 patients) and significant behavioral improvements (academic performance, attention, socialization, and aggression) were achieved in all. Two patients manifested violence pre-operatively; one had extreme behavior with violence toward teachers and peers despite low seizure burden. Since surgery, his behavior has normalized.

CONCLUSION

We identified 5 patients with severe behavioral disorders in the setting of lesional epilepsy, all of whom demonstrated improvement after surgery. The degree of behavioral abnormality was disproportionate to epilepsy severity, suggesting a more complicated mechanism by which lesional epilepsy impacts behavior. We propose a novel paradigm in which lesionectomy may offer behavioral benefit even when seizures are not refractory. Thus, behavioral improvement may be an important novel goal for neurosurgical resection in children with epileptic brain lesions.

Glioneuronal and Neuronal Tumors of the Central Nervous System

Glioneuronal and neuronal tumors (GNTs) are rare neoplasms composed of neural and glial elements frequently located in the temporal lobe. Epilepsy is the main symptom and diagnosis mostly occurs before adulthood. The great majority of GNTs are WHO grade I tumors, but anaplastic transformations and forms exist. Their common association with focal cortical dysplasia is well recognized and should be taken into consideration during neurophysiological presurgical and surgical planning since the aim of surgery should be the removal of the tumor and of the entire epileptogenic zone according to anatomo-electrophysiological findings. Surgery still remains the cornerstone of symptomatic GNT, while radiotherapy, chemotherapy, and new target therapies are generally reserved for anaplastic, unresectable, or evolving tumors. Furthermore, since many GNTs show overlapping clinical and neuroradiological features, the definition of specific histopathological, genetic, and molecular characteristics is crucial. Epileptological, oncological, neurosurgical, and pathological issues of these tumors make a multidisciplinary management mandatory.

Immunotherapy for Pediatric Brain and Spine Tumors: Current State and Future Directions

BACKGROUND

Brain tumors are the most common solid tumors and the leading cause of cancer-related deaths in children. Incidence in the USA has been on the rise for the last 2 decades. While therapeutic advances in diagnosis and treatment have improved survival and quality of life in many children, prognosis remains poor and current treatments have significant long-term sequelae.

SUMMARY

There is a substantial need for the development of new therapeutic approaches, and since the introduction of immunotherapy by immune checkpoint inhibitors, there has been an exponential increase in clinical trials to adopt these and other immunotherapy approaches in children with brain tumors. In this review, we summarize the current immunotherapy landscape for various pediatric brain tumor types including choroid plexus tumors, embryonal tumors (medulloblastoma, AT/RT, PNETs), ependymoma, germ cell tumors, gliomas, glioneuronal and neuronal tumors, and mesenchymal tumors. We discuss the latest clinical trials and noteworthy preclinical studies to treat these pediatric brain tumors using checkpoint inhibitors, cellular therapies (CAR-T, NK, T cell), oncolytic virotherapy, radioimmunotherapy, tumor vaccines, immunomodulators, and other targeted therapies.

KEY MESSAGES

The current landscape for immunotherapy in pediatric brain tumors is still emerging, but results in certain tumors have been promising. In the age of targeted therapy, genetic tumor profiling, and many ongoing clinical trials, immunotherapy will likely become an increasingly effective tool in the neuro-oncologist armamentarium.

Larotrectinib in NTRK Fusion-Positive High-Grade Glioneuronal Tumor: A Case Report

Glioneuronal tumors are rare central nervous system tumors with heterogeneous histological and molecular features. While the majority are low grade, a small percentage can behave aggressively. Due to the rarity of these tumors, there is no consensus on how to treat high-grade glioneuronal tumors, and they are often managed similarly to glial tumors. With the advent of molecular profiling, management decisions are increasingly determined by molecular alterations in the tumor rather than the tumor type, which can be a useful approach for tumor types that do not have robust supportive clinical trial data due to low prevalence. We present a case of an 18-year-old patient with a high-grade glioneuronal neoplasm initially treated with craniospinal irradiation, vincristine, and cyclophosphamide. He presented eight years later with a recurrent tumor and was found to be positive for MEF2D-NTRK1 fusion. He was treated with surgical resection and postoperative intensity-modulated radiation therapy (IMRT; 55.8 Gy) with concurrent temozolomide, followed by the NTRK inhibitor larotrectinib. He achieved a radiographic response, with a decrease in residual enhancement and radiographic improvement over the course of treatment. He remained in clinical and radiographic remission for six months. This demonstrates the successful treatment of a high-grade glioneuronal NTRK fusion-positive tumor with larotrectinib, which has only been previously reported once in the literature.

Anaplastic ganglioglioma - a diagnosis comprising several distinct tumour types

Anaplastic ganglioglioma is a rare tumour and diagnosis has been based on histological criteria. The 5^th edition of the World Health Organization Classification of Tumours of the Central Nervous System (CNS WHO) does not list anaplastic ganglioglioma as a distinct diagnosis due to lack of molecular data in previous publications AIM: We retrospectively compiled a cohort of 54 histologically diagnosed anaplastic gangliogliomas to explore whether the molecular profiles of these tumours represent a separate type or resolve into other entities METHODS: Samples were subjected to histological review, DNA methylation profiling and next generation sequencing. Morphologic and molecular data were summarised to an integrated diagnosis RESULTS: The majority of histologically diagnosed anaplastic gangliogliomas resolved into CNS WHO diagnoses of glial tumours, most commonly pleomorphic xanthoastrocytoma (16/54), glioblastoma, IDH wildtype and diffuse paediatric-type high-grade glioma, H3 wildtype and IDH wildtype (11 and 2/54) followed by low-grade glial or glioneuronal tumours including pilocytic astrocytoma, dysembryoplastic neuroepithelial tumour and diffuse leptomeningeal glioneuronal tumour (5/54), IDH mutant astrocytoma (4/54) and others (6/54). A subset of tumours (10/54) was not assignable to a CNS WHO diagnosis and common molecular profiles pointing to a separate entity were not evident CONCLUSION: In summary, we show that tumours histologically diagnosed as anaplastic ganglioglioma comprise a wide spectrum of CNS WHO tumour types with different prognostic and therapeutic implications. We therefore suggest assigning this designation with caution and recommend comprehensive molecular workup.

Diffusion histology imaging differentiates distinct pediatric brain tumor histology

High-grade pediatric brain tumors exhibit the highest cancer mortality rates in children. While conventional MRI has been widely adopted for examining pediatric high-grade brain tumors clinically, accurate neuroimaging detection and differentiation of tumor histopathology for improved diagnosis, surgical planning, and treatment evaluation, remains an unmet need in their clinical management. We employed a novel Diffusion Histology Imaging (DHI) approach employing diffusion basis spectrum imaging (DBSI) derived metrics as the input classifiers for deep neural network analysis. DHI aims to detect, differentiate, and quantify heterogeneous areas in pediatric high-grade brain tumors, which include normal white matter (WM), densely cellular tumor, less densely cellular tumor, infiltrating edge, necrosis, and hemorrhage. Distinct diffusion metric combination would thus indicate the unique distributions of each distinct tumor histology features. DHI, by incorporating DBSI metrics and the deep neural network algorithm, classified pediatric tumor histology with an overall accuracy of 85.8%. Receiver operating analysis (ROC) analysis suggested DHI’s great capability in distinguishing individual tumor histology with AUC values (95% CI) of 0.984 (0.982–0.986), 0.960 (0.956–0.963), 0.991 (0.990–0.993), 0.950 (0.944–0.956), 0.977 (0.973–0.981) and 0.976 (0.972–0.979) for normal WM, densely cellular tumor, less densely cellular tumor, infiltrating edge, necrosis and hemorrhage, respectively. Our results suggest that DBSI-DNN, or DHI, accurately characterized and classified multiple tumor histologic features in pediatric high-grade brain tumors. If these results could be further validated in patients, the novel DHI might emerge as a favorable alternative to the current neuroimaging techniques to better guide biopsy and resection as well as monitor therapeutic response in patients with high-grade brain tumors.

Primary Anaplastic Ganglioglioma of the Temporal Lobe With Brainstem Involvement: A Case Report and Literature Review

Anaplastic ganglioglioma (AGG) is a rare and aggressive counterpart of the more benign and frequently encountered glioma. Herein, we present a 21-year-old female who presented with episodes of total amnesia and complex partial seizures, which led to the diagnosis of AGG localized to the medial temporal lobe. She subsequently underwent surgical cytoreduction of the tumor three times with adjuvant chemoradiotherapy. The extent of resection throughout the surgeries was hindered by the extension of the tumor to critical neurovascular structures; during the last surgery, invasion into the pons was noted, which posed a significant clinical challenge.

Low-grade gangliogliomas in adults: A population-based study

BACKGROUND

Low-grade gangliogliomas (GGs) are rare tumors of the central nervous system in adults. This study aims to define their characteristics, prognostic factors, and the impact of different treatment patterns on survival.

METHODS

The Surveillance, Epidemiology, and End Results (SEER) database was used to investigate the potential clinicopathological factors of low-grade GGs in adult patients (age ≥18 years). Kaplan-Meier method and Cox regression model were utilized to evaluate the associations between variables and overall survival (OS).

RESULTS

A total of 703 adult patients diagnosed with low-grade GGs were identified between 2004 and 2016, with a median follow-up period of 60.0 months. The median age at diagnosis was 32.0 years, with 50.1% of patients being male, 84.2% white people, and 40.2% of married status. The predominant tumor site was located in temporal lobe (38.8%). The median OS time for the whole cohort was not reached. The 5- and 10-year OS rates for patients underwent gross total resection (GTR) were 92.5% and 87.2%, respectively. Univariate and multivariate analysis showed age, gender, tumor site, and treatment pattern were significant factors for OS. The employment of adjuvant radiotherapy (RT) and/or chemotherapy would significantly shorten OS time.

CONCLUSIONS

This is the largest retrospective study of adult low-grade GGs up to date. Younger age, female gender, temporal lobe location, and GTR indicated better survival. Adjuvant RT and/or chemotherapy should not be considered after whatever surgery in adult patients with low-grade GGs, unless the malignant transformation has been confirmed.

Clinicopathologic Features of Diencephalic Neuronal and Glioneuronal Tumors

Neuronal/mixed glioneuronal tumors are central nervous system neoplasms composed of neoplastic neuronal cell components or a mixture of glial and neuronal elements. They occur in cerebral hemispheres, posterior fossa, and spinal cord. Compared with other tumors at these locations, diencephalic neuronal/glioneuronal tumors are very rare and therefore not well characterized. We hereby performed clinicopathologic evaluation on 10 neuronal/glioneuronal tumors arising from the diencephalic region. Morphologically, these tumors resemble their histologic counterparts in other locations, except that lymphocytic infiltrates and microcalcifications are more common than Rosenthal fibers or eosinophilic granular bodies. The BRAFV600 mutation rate is 75%. Given the high percentage of samples being small biopsy specimens, the subtle histologic features and molecular findings greatly aided in establishing the pathologic diagnosis in several cases. At a median follow-up of 42 months, 71% of the tumors demonstrated radiological recurrence or progression, with median progression-free survival of 18 months. Recurrence/progression is observed in tumors across different histologic subtypes, necessitating additional therapies in 56% of the cases. Despite their bland histology, diencephalic neuronal/glioneuronal tumors are not clinically indolent. Their frequent recurrences warrant a close follow-up, and the prevalent BRAF mutation makes MAPK pathway inhibition a plausible treatment option when conventional therapies fail.

H3F3A-G34R mutant high grade neuroepithelial neoplasms with glial and dysplastic ganglion cell components

The recently described malignant neuro-epithelial tumors with histone H3F3A point mutations at G34 (NET-H3-G34) occur most often in cerebral hemispheres of teenagers and young adults, and have a generally adverse prognosis. These tumors have been histologically classified as glioblastoma or primitive neuroectodermal tumor (PNET) in the past, and have not been defined as a separate entity in the revised WHO classification of tumors of the CNS 2016. Here, we report two cases of NET-H3-G34 with glial and dysplastic ganglion cell components affecting teenagers. Patients were treated with surgery and radiochemotherapy with temozolomide. One patient underwent partial resection and deceased 21 months after diagnosis, while the other patient is alive without evidence of disease 15 months after total resection. So far, a dysplastic ganglion cell component has not been described in NET-H-G34, and its presence raises a possible relation to (anaplastic) gangliogliomas. Genome-wide copy number analysis did not provide unequivocal evidence that these tumors represent anaplastic variants of gangliogliomas, as opposed to NET-H3-G34. Our observations expand the morphologic spectrum of NET-H3-G34. Further cases of NET-H3-G34 with dysplastic ganglion cells should be clinically followed to find differences or similarities in their biological behavior, as compared to NET-H3-G34 and anaplastic gangliogliomas.

Pathologic and molecular aspects of anaplasia in circumscribed gliomas and glioneuronal tumors

Many breakthroughs have been made in the past decade regarding our knowledge of the biological basis of the diffuse gliomas, the most common primary central nervous system (CNS) tumors. These tumors as a group are aggressive, associated with high mortality, and have a predilection for adults. However, a subset of CNS glial and glioneuronal tumors are characterized by a more circumscribed pattern of growth and occur more commonly in children and young adults. They tend to be indolent, but our understanding of anaplastic changes in these tumors continues to improve as diagnostic classifications evolve in the era of molecular pathology and more integrated and easily accessible clinical databases. The presence of anaplasia in pleomorphic xanthoastrocytomas and gangliogliomas is assigned a WHO grade III under the current classification, while the significance of anaplasia in pilocytic astrocytomas remains controversial. Recent data highlight the association of the latter with aggressive clinical behavior, as well as the presence of molecular genetic features of both pilocytic and diffuse gliomas, with the recognition that the precise terminology remains to be defined. We review the current concepts and advances regarding histopathology and molecular understanding of pilocytic astrocytomas, pleomorphic xanthoastrocytomas, and gangliogliomas, with a focus on their anaplastic counterparts.

Association of patterns of care, prognostic factors, and use of radiotherapy-temozolomide therapy with survival in patients with newly diagnosed glioblastoma: a French national population-based study

Background

Glioblastoma is the most frequent primary malignant brain tumor. In daily practice and at whole country level, oncological care management for glioblastoma patients is not completely known.

Objectives

To describe oncological patterns of care, prognostic factors, and survival for all patients in France with newly-diagnosed and histologically confirmed glioblastoma, and evaluate the impact of extended temozolomide use at the population level.

Methods

Nationwide population-based cohort study including all patients with newly-diagnosed and histologically confirmed glioblastoma in France in 2008 and followed until 2015.

Results

Data from 2053 glioblastoma patients were analyzed (male/female ratio 1.5, median age 64 years). Median overall survival (OS) was 11.2 [95% confidence interval (CI) 10.7–11.9] months. The first-line therapy and corresponding median survival (MS, in months) were: 13% did not receive any oncological treatment (biopsy only) (MS = 1.8, 95% CI 1.6–2.1), 27% received treatment without the combination of radiotherapy (RT)–temozolomide (MS = 5.9, 95% CI 5.5–6.6), 60% received treatment including the initiation of the concomitant phase of RT–temozolomide (MS = 16.4, 95% CI 15.2–17.4) whom 44% of patients initiated the temozolomide adjuvant phase (MS = 18.9, 95% CI 18.0–19.8). Only 22% patients received 6 cycles or more of adjuvant temozolomide (MS = 25.5, 95% CI 24.0–28.3). The multivariate analysis showed that the risk of mortality was significantly higher for the non-progressive patients who stopped at 6 cycles (standard protocol) than those who continued the treatment, hazard ratio = 1.5 (95% CI 1.2–1.9).

Conclusion

In non-progressive patients, prolonging the adjuvant temozolomide beyond 6 cycles may improve OS.

Electronic supplementary material

The online version of this article (10.1007/s11060-018-03065-z) contains supplementary material, which is available to authorized users.

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.

A case of adult anaplastic cerebellar ganglioglioma

Background:

Anaplastic posterior fossa ganglioglioma in adults is exceedingly rare. To date, only one case of adult anaplastic posterior fossa ganglioglioma has been reported in the English literature and none has been described at the cerebellum. To our knowledge, this report is the third case of malignant posterior fossa ganglioglioma in adults and the first at the cerebellum. In general, this entity can be misdiagnosed preoperatively as a primary posterior fossa neoplasm, and by reporting our clinical and radiographic observations we want to add to the existing literature on this rare entity.

Case Description:

A 40-year-old man presented with a history of headaches and dizziness and progressive gait disturbance and was diagnosed with anaplastic ganglioglioma in the posterior fossa.

Conclusions:

Although rare, our case demonstrates that anaplastic ganglioglioma should be considered in the differential diagnosis of infratentorial tumors in adult patients.

Co-occurrence of histone H3 K27M and BRAF V600E mutations in paediatric midline grade I ganglioglioma

Ganglioglioma (GG) is a grade I tumor characterized by alterations in the MAPK pathway, including BRAF V600E mutation. Recently, diffuse midline glioma with an H3 K27M mutation was added to the WHO 2016 classification as a new grade IV entity. As co-occurrence of H3 K27M and BRAF V600E mutations has been reported in midline tumors and anaplastic GG, we searched for BRAF V600E and H3 K27M mutations in a series of 54 paediatric midline grade I GG (midline GG) to determine the frequency of double mutations and its relevance for prognosis. Twenty-seven patients (50%) possessed the BRAF V600E mutation. The frequency of the co-occurrence of H3F3A/BRAF mutations at diagnosis was 9.3%. No H3 K27M mutation was detected in the absence of the BRAF V600E mutation. Double-immunostaining revealed that BRAF V600E and H3 K27M mutant proteins were present in both the glial and neuronal components. Immunopositivity for the BRAF V600E mutant protein correlated with BRAF mutation status as detected by massARRAY or digital droplet PCR. The median follow-up of patients with double mutation was 4 years. One patient died of progressive disease 8 years after diagnosis, whereas the four other patients were all alive with stable disease at the last clinical follow-up (at 9 months, 1 year and 7 years) without adjuvant therapy. We demonstrate in this first series of midline GGs that the H3 K27M mutation can occur in association with the BRAF V600E mutation in grade I glioneuronal tumors. Despite the presence of H3 K27M mutations, these cases should not be graded and treated as grade IV tumors because they have a better spontaneous outcome than classic diffuse midline H3 K27M-mutant glioma. These data suggest that H3 K27M cannot be considered a specific hallmark of grade IV diffuse gliomas and highlight the importance of integrated histomolecular diagnosis in paediatric brain tumors.

Clinical, Imaging, Histopathological and Molecular Characterization of Anaplastic Ganglioglioma

Anaplastic ganglioglioma (AGG) is a rare and malignant variant of ganglioglioma. According to the World Health Organization classification version 2016, their histopathological grading criteria are still ill-defined. The aim of the present study was to assess the clinical, imaging, histopathological, and molecular characteristics and outcomes of AGGs in a large consecutive and retrospective adult and pediatric case series. Eighteen patients with AGGs (13 adults and 5 children) were identified (14 de novo and 4 secondary) from a cohort of 222 gangliogliomas (GG) (8%) treated at our institution between 2000 and 2015. AGGs represented a very aggressive disease with poor outcome (median progression-free survival, 10 months; median overall survival, 27 months). They were located in the temporal lobe only in 22% and presented with seizures (44%) or increased intracranial pressure (44%) at diagnosis. Concerning histopathological and molecular data, they shared morphological characteristics and BRAF V600E mutation (39%) with their benign counterparts but also showed hTERT promoter mutation (61%), p53 accumulation (39%), ATRX loss (17%), or p.K27M H3F3A mutation (17%). AGGs are malignant neoplasms requiring aggressive oncological treatment. In the perspective of targeted therapies, AGGs should be screened for BRAF V600E, hTERT, ATRX, and mutations of histone genes.