Isocitrate dehydrogenase 1 R132H mutation is not detected in angiocentric glioma

Angiocentric glioma: A case report and review of the literature

BACKGROUND

Angiocentric glioma (AG) is a rare, low-grade glioma with slow growth. In 2007, AG was first classified as a solid tumor according to the WHO classification of the central nervous system (WHO class I). The outcome and prognosis of most of the cases are very good, but a few cases with tumor metastasis and disease progression, even death, have been reported. We report a case and systematically analyze previous literature to increase our understanding of the disease and determine the factors that may affect disease progression to make prognostic judgments.

CASE PRESENTATION

A young male patient complained of a 3-year history of epilepsy. Anti-epileptic drug treatment was ineffective. An imaging examination revealed a lesion in the left parietal cortex area. Thus, the lesion was completely resected. The pathological diagnosis was angiocentric glioma. During a follow-up of two years, the patient had epilepsy relief controlled by sodium valproate and a disease-free period.

CONCLUSION

AG is an epilepsy-related low-grade glioma that heals after complete resection in most reported cases. However, few reported cases have had disease progression and death. This result may be due to the pathological complexity of the diseased tissue. In addition, AG is usually found to have an MYB-QKI rearrangement on genetic analysis. Due to the small number of reported cases and studies, our understanding and knowledge of this disease are still lacking. The potential malignant changes and prognostic factors need to be verified in more than clinical cases and basic research in the future.

Molecular Immunohistochemical Profile of Angiocentric Glioma

Background and Purpose

Angiocentric glioma is a rare, World Health Organization grade I tumor that is seen predominantly in children and young adults and typically presents with seizures. Histologically, it shows features of both infiltrating glioma and ependymoma.

Methods

We examined molecular immunohistochemical markers which could help in distinguishing this entity from its differential diagnostic considerations.

Results

We retrospectively reviewed the clinicopathologic features of angiocentric gliomas and performed immunohistochemical staining for isocitrate dehydrogenase 1 (IDH-1) (R132H), p53, ATRX, BRAF V600E, Ki-67, and H3 K27M on formalin-fixed, paraffin-embedded tissue. Seven cases in total were found and included six excisional specimens and one biopsy. ATRX staining was retained in all cases. There was no evidence of staining with antibodies to IDH-1 (R132H), H3 K27M, or BRAF V600E. Five tumors showed no staining with antibody to p53 and two tumors showed less than 5% positivity. Ki-67 indices were less than 1% in five tumors, 4-5% in one tumor, and 9-10% in one tumor.

Conclusions

In conclusion, the immunohistochemical markers for ATRX, p53, IDH-1 (R132H), BRAF V600E, H3 K27M show wild-type staining, potentially aiding in avoiding misdiagnoses in cases morphologically similar to other low-grade gliomas. Ki-67 labeling indices are low in most tumors.

Clinical characteristics, treatment and prognosis of angiocentric glioma

Angiocentric glioma (AG) is a rare subtype of neuroepithelial tumor in children and young adults that commonly presents with seizures. To study the clinical characteristics, treatment and prognosis of patients with AG, the features of two cases of AG were described and 108 cases reported in the literature were assessed. The cases of the present study were two males aged 8 and 16 years, who mainly presented with seizures. MRI revealed superficial, non-enhanced lesions in the left temporal and right frontal lobe, respectively. The two patients underwent gross total resection (GTR) and remained seizure-free without neurological deficits after 3.5 and 2.5 years, respectively. Histopathological examination revealed that the tumors consisted of monomorphous cells that surrounded the blood vessels and neurons in the cerebral cortex, and formed concentric sleeves or pseudorosettes. Furthermore, immunostaining indicated that the diffuse infiltrative neoplastic cells were positive for glial fibrillary acidic protein and a dot-like pattern of epithelial membrane antigen was observed. AG mostly appeared similar to low-grade gliomas on MRI. GTR of the lesions was curative and radiation or chemotherapy were not required. AG typically has a favorable prognosis, with low mortality and incidence of disability.

Angiocentric glioma: Drop Metastases to the Spinal Cord

BACKGROUND

Angiocentric glioma (AG) is an epileptogenic low grade (World Health Organization grade I) glial tumor with astrocytic and ependymal differentiation, most commonly affecting the pediatric and adolescent population. Despite its infiltrating histological growth kinetics, it is widely accepted that AG has a low potential for aggressive behavior.

CASE DESCRIPTION

We present the case of a 42-year-old man who represents the first documented case of not only extracranial manifestation of AG, but also spinal metastatic dissemination. Our patient initially presented with a generalized tonic clonic seizure; following a biopsy, he was diagnosed with a low-grade supratentorial astrocytoma and subsequently received fractionated radiotherapy. He presented 10 months later with worsening dorsal column symptoms and was found to have a contrast-enhancing intradural extramedullary lesion that was surgically resected and histologically confirmed as an AG.

CONCLUSION

Further research is required to examine the microenvironment and potential for malignant change in this tumor.

Brainstem angiocentric glioma: report of 2 cases

Angiocentric glioma is a rare tumor that was recognized by the WHO Classification of Tumours of the Central Nervous System as a distinct clinicopathological entity in 2007. Since this initial description, the vast majority of cases of angiocentric glioma reported in the literature have involved tumors of the cerebral hemispheres. To date, only 1 case of angiocentric glioma arising from the posterior midbrain has been reported. The authors present the cases of 2 pediatric patients who were found to have brainstem angiocentric gliomas. The clinical course, radiological and pathological features, treatment, and follow-up are described. The first case is one of a 5-year-old girl who presented with double vision, headache, and nausea and was found to have a midbrain lesion with pathological features consistent with angiocentric glioma. She was treated with resection and endoscopic third ventriculostomy (ETV), followed by close observation and serial neuroimaging. The second case is one of a 6-year-old boy who presented with progressive mouth drooping and problems with balance. He was found to have a pontine lesion with pathological features consistent with angiocentric glioma. This patient was treated with ETV, followed by close observation and serial neuroimaging. This report includes 6 and 1.5 years of follow-up of the patients, respectively. While there are limited data regarding the prognosis or long-term management of patients with brainstem angiocentric gliomas, the cases described in this report suggest an indolent course for this tumor, similar to the course of angiocentric gliomas located in the cerebral hemispheres.

Clinical attributes and surgical outcomes of angiocentric gliomas

Angiocentric gliomas (AG) are exceedingly rare low-grade neoplasms which often present in the form of intractable epilepsy within younger patients. The current study extensively reviews all reported cases which were pathologically verified as AG in the literature to analyze clinical attributes and surgical outcomes of this neoplasm. There were 88 patients with AG reported in the literature consisting mostly of pediatric cases. The sex distribution consisted of 45 males and 36 females with the remaining seven cases not documenting sex. The average age of initial diagnosis was 16years with almost half of all diagnosed patients being within the first decade of life. In cases where extent of resection was reported, gross total resection (GTR) was achieved in 54 patients, subtotal resection (STR) in 16, and biopsy only in three. Post-operative complications were transient and only occurred in three patients with no reports of death following surgery. Only five cases reported tumor recurrence on follow-up. Eight patients had seizure recurrence post-operatively and GTR offered improved rates of seizure control when compared to STR (p=0.0005). Nearly half of the cases of AG are diagnosed within the first decade of life and they usually manifest with intractable seizures. GTR appears to offer better seizure control in the post-operative period. Surgical resection is the mainstay therapy for AG as post-operative complications and tumor recurrence remain uncommon. Since the number of reported cases is limited, future studies with longer follow-up periods will help elaborate more long-term outcomes.

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.

"Unusual brain stone": heavily calcified primary neoplasm with some features suggestive of angiocentric glioma

This 40-year-old man presented with a 5-month history of progressive right-sided headache associated with visual blurring. He also had a history of epilepsy but had been seizure free with medication for the past 10 years. An initial CT scan of his brain performed 16 years previously had revealed a small area of calcification in the right parietal region. In the current presentation, he had a left-sided homonymous hemianopia but no other neurological deficits. A CT scan of his brain showed a much larger calcified, partly cystic lesion in the right parietal region. Because he was symptomatic, the lesion was excised and the cyst was drained. Histological examination of the excised tissue showed an unusual primary tumor that was difficult to classify but had some features of angiocentric glioma. The heavy calcification, mixed-density cell population, and regions with features of angiocentric glioma were most unusual. The patient remained asymptomatic 5 years after surgery, and follow-up scans did not show recurrence.

[A unusual brain cortical tumor: angiocentric glioma]

We report the case of an 11-year-old girl, who was admitted for surgery of an epilepsy-associated brain tumor. The radiological and clinical hypothesis was dysembryoplasic neuroepithelial tumor. Histopathological examination revealed a tumoral proliferation composed of spindle-shaped cells with palisade arrangements around vessels. Tumor cells have small, round and regular nuclei without atypia or mitosis. On immunohistochemistry, the neoplastic cells strongly expressed GFAP and showed a characteristic cytoplasmic dot-like staining with EMA (epithelial membrane antigen). Ki-67 labeling index was low. Molecular analysis failed to reveal the V600E mutation of BRAF gene. The patient was free of seizures after surgery. Angiocentric glioma is a rare brain tumor occuring preferably in children and young adults and is associated with seizures. The precise histogenesis remains debated. The treatment of choice is total resection. The prognosis is favorable if totally resected.

A neuropathology-based approach to epilepsy surgery in brain tumors and proposal for a new terminology use for long-term epilepsy-associated brain tumors

Every fourth patient submitted to epilepsy surgery suffers from a brain tumor. Microscopically, these neoplasms present with a wide-ranging spectrum of glial or glio-neuronal tumor subtypes. Gangliogliomas (GG) and dysembryoplastic neuroepithelial tumors (DNTs) are the most frequently recognized entities accounting for 65 % of 1,551 tumors collected at the European Epilepsy Brain Bank (n = 5,842 epilepsy surgery samples). These tumors often present with early seizure onset at a mean age of 16.5 years, with 77 % of neoplasms affecting the temporal lobe. Relapse and malignant progression are rare events in this particular group of brain tumors. Surgical resection should be regarded, therefore, also as important treatment strategy to prevent epilepsy progression as well as seizure- and medication-related comorbidities. The characteristic clinical presentation and broad histopathological spectrum of these highly epileptogenic brain tumors will herein be classified as “long-term epilepsy associated tumors—LEATs”. LEATs differ from most other brain tumors by early onset of spontaneous seizures, and conceptually are regarded as developmental tumors to explain their pleomorphic microscopic appearance and frequent association with Focal Cortical Dysplasia Type IIIb. However, the broad neuropathologic spectrum and lack of reliable histopathological signatures make these tumors difficult to classify using the WHO system of brain tumors. As another consequence from poor agreement in published LEAT series, molecular diagnostic data remain ambiguous. Availability of surgical tissue specimens from patients which have been well characterized during their presurgical evaluation should open the possibility to systematically address the origin and epileptogenicity of LEATs, and will be further discussed herein. As a conclusion, the authors propose a novel A–B–C terminology of epileptogenic brain tumors (“epileptomas”) which hopefully promote the discussion between neuropathologists, neurooncologists and epileptologists. It must be our future mission to achieve international consensus for the clinico-pathological classification of LEATs that would also involve World Health Organization (WHO) and the International League against Epilepsy (ILAE).

Characterizing invading glioma cells based on IDH1-R132H and Ki-67 immunofluorescence

Glioma, the most common primary brain tumor, is characterized by proliferative-invasive growth. However, the detailed biological characteristics of invading glioma cells remain to be elucidated. A monoclonal antibody (clone HMab-1) that specifically and sensitively recognizes the isocitrate dehydrogenase-1 (IDH1) protein carrying the R132H mutation can identify invading glioma cells by immunostaining. To investigate the degree of invasion in gliomas of distinct grades and the proliferative capacity of the invading cells, immunofluorescent staining was conducted using antibodies against IDH1-R132H and Ki-67 on 11 surgical and autopsy specimens of the tumor core and the invading area. Higher numbers of IDH1-R132H-positive cells in the invading area correlated with a higher tumor grade. Double staining for IDH1-R132H and Ki-67 demonstrated that most invading cells that expressed IDH1-R132H were not stained by the Ki-67 antibody, and the ratio of Ki-67-positive cells among IDH1-R132H-positive cells was significantly lower in the invasion area than in the tumor core in all grades of glioma. These data suggest that higher grade gliomas have a greater invasive potential and that invading cells possess low proliferative capacity.

Malignant glioma with angiocentric features

Angiocentric glioma is a recently recognized benign brain tumor with unknown histogenesis. Most of these tumors are mitotically low in activity in accord with their benign clinical course. However, increased mitotic activity has been noted in several cases, one of which had an ultimately fatal outcome. Here, the authors present a tumor showing angiocentric glioma and glioblastoma-like features, with recurrence of the lower-grade component after radiotherapy. A 15-year-old boy presented with a 3-month history of progressive left-sided weakness and headache. Magnetic resonance imaging showed a large heterogeneous mass in the right frontal lobe, with mild post-Gd enhancement. A gross-total resection was obtained. Histopathological examination of the resected tissue revealed a tumor with 2 distinct appearances: 1) a mildly to moderately cellular infiltrating tumor with angiocentric glioma characteristics, and 2) a markedly cellular glioblastoma-like tissue with necrosis and microvascular proliferation. The patient received a course of postoperative radiotherapy to 59.4 Gy in 33 fractions administered over the course of 6.5 weeks, but his tumor recurred 4 months after resection. A second resection was then performed. The recurrent tumor exhibited radiation-induced changes and persistent characteristics of angiocentric glioma, but it had fewer malignant features; the mitotic activity was lower, and there was no necrosis or microvascular proliferation. The findings in this case, along with those in several previously reported cases, suggest that angiocentric gliomas may have a malignant variant or malignant transformation. Angiocentric gliomas with malignant features tend to recur, for which surgical intervention followed by radiotherapy and chemotherapy should be offered as a therapeutic option.