Meningeal tumors of childhood and infancy. An update and literature review

Juvenile Xanthogranuloma of the Head and Neck: Imaging Findings in 11 Cases

BACKGROUND

Juvenile Xanthogranuloma (JXG) is a non-Langerhans cell histiocytosis, occurring mainly in infancy. With an extracutaneous lesion, its diagnosis is difficult, because of a wide clinical spectrum. Here we demonstrate and characterize imaging features of 11 patients with JXG of the head and neck in various locations.

MATERIAL AND METHODS

We recorded clinical data and reviewed all imaging studies of 11 patients with JXG of the head and neck. Ultrasonography (US) alone was performed in 1 patient; MRI alone in 6 patients; US and MRI in 1 patient; and US, CT, and MRI in 3 patients. We evaluated the following characteristics in all studies: location and number of lesions, echogenicity and vascularization on US, density on CT, signal intensity on T 1 - and T 2 -weighted images, ADC and enhancement on MRI, and tumor boundaries and bone involvement.

RESULTS

Lesions were well-defined in 9 cases, and bone erosion was present in 2. On US, lesions were hypoechoic or hyperechoic and with or without vascularization. On CT, lesions were hyper-dense, with no calcification. On MRI, lesions were mildly hyper-intense or iso-intense on T 1 -weighted images in 8 of 9 patients, hypo-intense on T2-weighted images in 7 of 10, low ADC in 7 of 9, and enhancement in 7 of 7.

CONCLUSIONS

The diagnosis of extra cutaneous JXG may be proposed, with the following suggestive criteria: age < 1 year, well-defined lesion, mild hyper-intensity on T 1 -weighted images, hypo-intensity on T 2 -weighted images, low ADC, enhancement, and possible adjacent bone involvement.

Molecular classification and grading of meningioma

PURPOSE

Meningiomas are the most common primary intracranial tumor in older adults (Ostrom et al. in Neuro Oncol 21(Suppl 5):v1-v100, 2019). Treatment is largely driven by, in addition to patient characteristics and extent of resection/Simpson grade, the World Health Organization (WHO) grading of meningiomas. The current grading scheme, based predominantly on histologic features and only limited molecular characterization of these tumors (WHO Classification of Tumours Editorial Board, in: Central nervous system tumours, International Agency for Research on Cancer, Lyon, 2021), (Mirian et al. in J Neurol Neurosurg Psychiatry 91(4):379-387, 2020), does not consistently reflect the biologic behavior of meningiomas. This leads to both under-treatment and over-treatment of patients, and hence, suboptimal outcomes (Rogers et al. in Neuro Oncol 18(4):565-574). The goal of this review is to synthesize studies to date investigating molecular features of meningiomas as they relate to patient outcomes, in order to clarify best practices in assessing and, therefore, treating meningiomas.

METHODS

The available literature of genomic landscape and molecular features of in meningioma was screened using PubMed.

RESULTS

Greater understanding of meningiomas is reached by integrating histopathology, mutational analysis, DNA copy number changes, DNA methylation profiles, and potentially additional modalities to fully capture the clinical and biologic heterogeneity of these tumors.

CONCLUSION

Diagnosis and classification of meningioma is best accomplished using a combination of histopathology with genomic and epigenomic factors. Future classification schemes may benefit from such an integrated approach.

Extra-axial, dural-based atypical teratoid/rhabdoid tumor

Atypical teratoid/rhabdoid tumors (ATRTs) are malignant central nervous system tumors that affect early childhood (< 3 years), and mostly located in the infratentorial space. Owing to an infrequent occurrence, their radiological features have not been completely defined. Nevertheless, these are characteristically intra-axial except for few instances in the cerebellopontine angle region. We describe a case of a 10-year-old boy who harbored an extra-axial, dural-based ATRT in the right parietal region. The lesion was totally excised followed by adjuvant chemo-radiotherapy. At 10-month follow-up, he was well with no recurrence. The report intends to highlight an atypical imaging presentation of ATRT in an older child, and adds to the radiological spectrum. This uncommon pathology should be borne in mind, even in a supratentorial dural-based location.

Molecular profiling of pediatric meningiomas shows tumor characteristics distinct from adult meningiomas

In contrast to adults, meningiomas are uncommon tumors in childhood and adolescence. Whether adult and pediatric meningiomas differ on a molecular level is unclear. Here we report detailed genomic analyses of 37 pediatric meningiomas by sequencing and DNA methylation profiling. Histologically, the series was dominated by meningioma subtypes with aggressive behavior, with 70% of patients suffering from WHO grade II or III meningiomas. The most frequent cytogenetic aberrations were loss of chromosomes 22 (23/37 [62%]), 1 (9/37 [24%]), 18 (7/37 [19%]), and 14 (5/37 [14%]). Tumors with NF2 alterations exhibited overall increased chromosomal instability. Unsupervised clustering of DNA methylation profiles revealed separation into three groups: designated group 1 composed of clear cell and papillary meningiomas, whereas group 2A comprised predominantly atypical meningiomas and group 2B enriched for rare high-grade subtypes (rhabdoid, chordoid). Meningiomas from NF2 patients clustered exclusively within groups 1 and 2A. When compared with a dataset of 105 adult meningiomas, the pediatric meningiomas largely grouped separately. Targeted panel DNA sequencing of 34 tumors revealed frequent NF2 alterations, while other typical alterations found in adult non-NF2 tumors were absent. These data demonstrate that pediatric meningiomas are characterized by molecular features distinct from adult tumors.

Clinical features and long-term outcomes of pediatric meningiomas

OBJECTIVE

Pediatric meningiomas are relatively rare and have atypical clinical features compared to adults. The purpose of this work is to report our 15-year experience in the management of pediatric meningiomas and assess their clinical characteristics, pathological features, and prognostic factors.

METHODS

A total of 40 children (age ≤ 15 years) who were diagnosed as pediatric meningiomas were enrolled in this study. Patient information including clinical presentation, gender, age at time of diagnosis, histopathological features, tumor location, tumor volume, treatment methods, and follow-up data were extracted and analyzed.

RESULTS

The mean age at diagnosis was 10.78 ± 3.50 years (range 2-15 years) in 40 patients with a male to female ratio of 1:1.11. Headache, epilepsy, visual disturbance, and limb weakness are common clinical manifestations. Two patients had multiple intracranial meningiomas. Fourteen (33.3%) of pediatric meningiomas were high grade meningiomas. Seven patients (17.5%) were treated with STR, while GTR was achieved in 33 patients (82.5%). The mean follow-up period was 82.1 months (range 9-173 months). Recurrence occurred in 9 patients (22.5%), and 5 patients (12.5%) passed away.

CONCLUSION

The incidence of pediatric meningiomas increases with advancing age. In pediatric patients, the percentage of high-grade tumors is higher than adults. Younger children were more likely to have high-grade meningiomas, while patients with tumors located in skull base or parasagittal/falx tend to have low-grade meningiomas. The WHO grade III meningiomas were significantly correlated with poor prognosis. Adjuvant radiotherapy after surgery can improve prognosis and may be a potential treatment strategy in children with malignant meningiomas.

Giant chondrosarcoma of the falx in an adolescent: A case report

Background:

Intracranial chondrosarcomas are slowly growing malignant cartilaginous tumors that are especially rare in adolescents.

Case Description:

A 19-year-old woman with no medical history presented with symptoms of intermittent facial twitching and progressive generalized weakness for 6 months. The patient’s physical examination was unremarkable. Imaging revealed a large bifrontal mass arising from the falx cerebri, with significant compression of both cerebral hemispheres and downward displacement of the corpus callosum. The patient underwent a bifrontal craniotomy for gross total resection of tumor. Neuropathologic examination revealed a bland cartilaginous lesion most consistent with low-grade chondrosarcoma. Her postoperative course was uneventful, and she was discharged to home on postoperative day 3.

Conclusion:

This is an unusual case of an extra-axial, non-skull base, low-grade chondrosarcoma presenting as facial spasm in an adolescent patient.

How Important Is to Know the Psychosocial Performance in an Operated Child of Meningioma? Devil Is in the Details

Background:

Meningioma constitutes only 0.4%–4.1% of all the pediatric tumors. This article aims to find the impact of the pediatric meningioma surgery on the developmental and scholastic performance among these children over long-term follow-up.

Materials and Methods:

This study is a retrospective analysis of all the histopathological proven pediatric meningioma and a cross-sectional analysis to study the functional outcome, using Malin’s Intelligence Scale for Indian children (MISIC); scholastic performance was assessed from behavioral checklist for screening the learning disabled (BCSLD) and subjective self-filled questionnaire to know parent satisfaction.

Results:

Twenty-eight patients (mean age 14.52 ± 0.722 years) (M:F = 16:12) were analyzed (6 [21.4%] were grade-schooler and 22 [78.5%] were teenage), with most common symptom being headache (n = 20, 71.4%) and mean duration of symptoms was 11.19 ± 16.25 days. The mean intelligent quotient (IQ) of grade-schooler was 83.4 ± 9.072 compared to 75.69 ± 9.903 among teenage group. The BCSLD analyses showed that the postoperative score was poorer. Similarly, an average change in BCSLD was observed among the patients with complications (10) compared to the patients without complication (8).

Conclusion:

The discontinuation in schooling or lack of alternative education may lead to poor MISIC scores, wrongly categorizing the children in poor IQ group. In pediatric benign disease such as meningioma, the holistic approach should be opted from the time of first visit to neurological care team.

Meningioma: A Pathology Perspective

Meningiomas are dural-based neoplasms that account for ∼37% of all intracranial tumors in the adult population. They can occur anywhere within the central nervous system and have a predilection for females. The World Health Organization classifies meningiomas into 3 grades based on increased risk of recurrence and associated mortality in grade III tumors. Although most tumors are categorized as low-grade, up to ∼15%-20% demonstrate more aggressive behavior. With the long-recognized association with neurofibromatosis type 2 gene mutation, putative driver mutations can be attributed to ∼80% of tumors. Several germline mutations have also been identified in some cases of familial meningiomatosis such as SMARCE1, SUFU, PTEN, and BAP1. Finally, in addition to genetic data, epigenetic alterations, specifically deoxyribonucleic acid methylation, are being increasingly recognized for their prognostic value, potentially adding objectivity to a currently subjective grading scheme.

A Treatise on Pediatric Meningiomas: Single-center Retrospective Cohort Experience and Review of Literature

Background

Pediatric meningiomas are infrequently encountered in clinical practice. In comparison to adults, they have a distinct pathophysiology and clinical presentation. They are benign but locally aggressive tumors. Radical excision often culminates in good outcome.

Aim

The aim of this study was to study the demographic profile, clinico-radiological features, pathophysiology, and surgical outcome of childhood meningiomas.

Materials and Methods

The case records of patients <18 years of age operated for meningiomas in our institute from 1985 to 2015 were retrieved. The demographic profile, clinical and radiological features, surgical approach, extension of resection, and surgical outcome were recorded and subsequently analyzed.

Results

Among 37 patients, 20 were males and 17 were females. The mean age was 13 years. Predisposing etiologies such as neurofibromatosis and radiation exposure were identified in 20% of the study population. There were 31 intracranial and 6 spinal meningiomas. Headache associated with vomiting was the most common presenting complaint. Majority were supratentorial tumors. A safe maximal excision was attempted in each case. Recurrence was noted in five patients. Average follow-up was approximately 24 months. Two patients succumbed to the illness. Approximately, 30% of patients were rendered morbid.

Conclusion

Although rare, pediatric meningiomas are biologically different from their adult counterparts. They have a male predominance, common in intraventricular region and cystic in nature. Radical excision is associated with good prognosis. Although benign, they are aggressive in nature and have a tendency to recur. The response to adjuvant therapy is modest. Further molecular research and genetic studies are necessary to understand the biology of pediatric meningiomas, which will help in the identification of targeted molecular therapy.

Pediatric meningiomas: 10-year experience with 39 patients

OBJECTIVE

The purpose of this article was to study the characteristics of pediatric meningiomas, including the clinical symptom, anatomic location, radiological finding, treatment approaches, and long-term surgical outcome as well as the possible influence factors of the prognosis.

METHODS

We retrospectively reviewed the medical records and follow-up data of 39 pediatric patients who were treated by operation for intracranial meningiomas in West-China Hospital between 2009-2019.

RESULTS

The incidence of pediatric meningioma was 0.74%. The mean age at surgery was 12.2 years and the ratio of male to female was 1.3. Three cases (7.7%) were related to neurofibromas. WHO grade I was found in 26 patients (66.7%) and higher grades was seen in 13 (33.3%). The most common location sites were convexity (35.9%). Gross total excision was achieved in 28 patients (71.8%). The mean follow-up period was 54.4 months. The recurrence rate was 41.9%. By survival analysis, only gross total resection (p = 0.028) was associated with favorable outcome.

CONCLUSION

Meningiomas in children are very rare and have a slight male predominance. Pediatric meningiomas are more commonly located in intraventricular and have higher incidence rate of high-grade than that in adults. Although being challenging, the gross total excision should be underdone to achieve a better prognosis.

Calvarial Melanotic Neuroectodermal Tumor of Infancy with Rhabdomyosarcomatous differentiation-A Rare Case

BACKGROUND

Malignant neuroectodermal tumor of infancy is a rare neural crest cell-derived neoplasm of infants. Histologically, melanotic neuroectodermal tumor of infancy usually consists of 2 types of cells: neuroblast-like and melanocyte-like cells. Here we present a rare case of melanotic neuroectodermal tumor of infancy containing a third type of cell population, that is, rhabdomyoblasts in addition to the above two.

CASE DESCRIPTION

We report a case of a 10-month-old female child who was brought to us with complaints of swelling over the right forehead for the last 9 months, which started increasing in size rapidly 3 months before presenting to us. Noncontrast computed tomography scan showed a large well-defined extra-axial lesion in the right frontotemporal region. The child underwent an open biopsy under general anesthesia. Histopathological sections showed a malignant small round cell tumor consisting of hyperchromatic cells lying in sheets and lobules separated by fibrous septae. The patient underwent 7 cycles of neoadjuvant chemotherapy over a period of 2 months. The patient underwent right frontotemporal craniotomy and gross total excision of the lesion as a definitive surgery. Postoperatively, the patient was stable, and there was no new deficit. Histopathology revealed neuroblast-like and melanocyte-like cells with rhabdomyosarcomatous differentiation. The patient received chemotherapy in the postoperative period. The patient had recurrence of the tumor and died 8 months after the surgery.

CONCLUSIONS

Calvarial malignant neuroectodermal tumor of infancy with rhabdomyosarcomatous differentiation is a rare entity with no cases being reported before. Neoadjuvant chemotherapy with surgical excision can be a promising modality of treatment.

Pediatric meningioma: a clinicopathologic and molecular study with potential grading implications

Meningiomas are common in adults (~35% of brain tumors) but rare in children, where they exhibit unique clinical, pathological and molecular features compared to adult counterparts. Thus, data generated from adult cohorts may be imperfectly suited to guiding diagnostic, prognostic and treatment decisions for children. We studied 50 meningioma patients ≤18 years with available clinical and pathological data to address the need for data obtained in the pediatric setting. As previously described, we noted a slight bias toward male patients and a higher proportion of spinal tumors compared to adults. Thirty-eight of 50 specimens were further analyzed by next generation sequencing. Loss-of-function mutations in NF2 and chromosome 22 losses were common, but pathogenic variants in other genes (SMARCB1, FUBP1, BRAF, TERT promoter, CHEK2, SMAD and GATA3) were identified in a minority of cases. Copy number variants outside of chromosomes 22 and 1 were infrequent. H3K27 hypomethylation, a useful biomarker in adult tumors, was not found in our cohort. In exploring the correlation between mitotic count and recurrence-free survival, we found a threshold of six mitoses per 10 high powered fields as the optimal cutoff in predicting recurrence-free survival. If independently validated in larger studies, adjusted grading thresholds could enhance the clinical management of pediatric meningiomas.

Meningioma with rhabdoid features combined with meningioangiomatosis in infancy: a novel combination

Meningioangiomatosis is a rare histologically distinct abnormality that is occasionally associated with intracranial meningioma. The rhabdoid variant of meningioma is also uncommon and is classified as a World Health Organization Grade III tumour. We report a case of meningioangiomatosis in conjunction with a meningioma with prominent rhabdoid features, in an infant male who underwent complete surgical resection of the lesion. The patient has been followed up for 6 years with no disease recurrence. To our knowledge, this is the first report in the literature describing meningioangiomatosis combined with a meningioma with rhabdoid features.

Meningiomas in children

Meningiomas in children are poorly understood because they are rare. Recent reports have provided a more complete description of their incidence, genetics, imaging features, and outcome. In general, meningiomas in children are more likely to be higher grade, present in atypical locations, and have a higher risk of recurrence. The challenges encountered in children with respect to surgical and postoperative management are unique. Improved understanding of pediatric meningiomas, as well as the availability of new surgical, medical, and radiation therapies, creates opportunities to improve outcomes in this unique population.

Management of pediatric CNS meningiomas: CCHE-57357 experience in 39 cases

PURPOSE

Our aim is to present our experience in the management of pediatric meningiomas in the largest referral center in Egypt for pediatric tumors focusing on variables including clinical picture, anatomic location, histopathology, treatment strategies, and outcome together with their possible correlation to prognosis.

METHODS

We retrospectively reviewed the medical records of 39 pediatric patients who were treated for CNS meningiomas in Children's Cancer Hospital-Egypt (CCHE-57357) 2007-2017.

RESULTS

The prevalence of pediatric meningioma was 1.42%. Four cases had type 2 neurofibromatosis (NFII). The mean age was 8.19 years. The presence of NFII was associated with challenging multiple lesions, older age of presentation and poorer prognosis and functional outcome. Convexity was the commonest location. Gross total resection (GTR) was achieved in 28 cases, subtotal resection (STR) in 8 cases, and biopsy was decided in 3 patients. Histopathological examination revealed WHO grade I in 16 patients and higher grades in 23 patients (59%). The 5-year overall survival (OS) rate was 87.8% while the 5-years event-free survival (EFS) rate was 85.6%. Tumor location, histopathology, and clinical presentation were not statistically correlated to prognosis.

CONCLUSIONS

Pediatric CNS meningiomas are uncommon pediatric tumors but of an aggressive clinical and pathological behaviors as compared to adult meningiomas. The presence of NFII is associated with a poorer prognosis and functional outcomes. Although being challenging, the maximum and safe surgical excision should be exercised even in recurrent cases in order to achieve the best outcome. Adjuvant radiotherapy provides good tumor control for inoperable residual atypical or anaplastic meningiomas.

Pediatric meningiomas: 65-year experience at a single institution

OBJECTIVE Meningiomas are relatively common, typically benign neoplasms in adults; however, they are relatively rare in the pediatric population. Pediatric meningiomas behave very differently from their adult counterparts, tending to have more malignant histological subtypes and recur more frequently. The authors of this paper investigate the risk factors, pathological subtypes, and recurrence rates of pediatric meningiomas. METHODS A retrospective chart review was conducted at the University of Iowa to identify patients 20 years old and younger with meningiomas in the period from 1948 to 2015. RESULTS Sixty-seven meningiomas in 39 patients were identified. Eight patients had neurofibromatosis, 2 had a family history of meningioma, and 3 had prior radiation exposure. Twelve (31%) of the 39 patients had WHO Grade II or III lesions, and 15 (38%) had recurrent lesions after resection. CONCLUSIONS Pediatric meningiomas should be considered for early treatment and diligent follow-up.

Evaluation of NF2 Gene Deletion in Pediatric Meningiomas Using Chromogenic In Situ Hybridization

Meningiomas are uncommon childhood tumors. They could be of significant size at presentation, which has been associated with difficult surgical excision, high recurrence rate, and possibly aggressive clinical behavior. Monosomy 22 is a common molecular event in this neoplasm. Additionally, losses on chromosomes 1,7,10, and 14 have been identified in clinically aggressive meningiomas. Using chromogenic in situ hybridization, we studied a group of pediatric meningiomas, including neurofibromatosis type II—associated, sporadic, and radiation-induced cases. We found NF2 gene deletion in about 72% of the cases, with corresponding absent or minimal merlin protein expression by immunohistochemistry. Our findings confirm that the NF2 gene plays a role in the tumorigenesis of pediatric meningiomas and that chromogenic in situ hybridization is an efficient, economic, and reliable method for routinely assessing NF2 gene deletion in formalin-fixed, paraffin-embedded tissues.

NRAS(Q61K) mutated primary leptomeningeal melanoma in a child: case presentation and discussion on clinical and diagnostic implications

Background

Primary melanocytic neoplasms are rare in the pediatric age. Among them, the pattern of neoplastic meningitis represents a peculiar diagnostic challenge since neuroradiological features may be subtle and cerebrospinal fluid analysis may not be informative. Clinical misdiagnosis of neoplastic meningitis with tuberculous meningitis has been described in few pediatric cases, leading to a significant delay in appropriate management of patients. We describe the case of a child with primary leptomeningeal melanoma (LMM) that was initially misdiagnosed with tuberculous meningitis. We review the clinical and molecular aspects of LMM and discuss on clinical and diagnostic implications.

Case presentation

A 27-month-old girl with a 1-week history of vomiting with mild intermittent strabismus underwent Magnetic Resonance Imaging, showing diffuse brainstem and spinal leptomeningeal enhancement. Cerebrospinal fluid analysis was unremarkable. Antitubercular treatment was started without any improvement. A spinal intradural biopsy was suggestive for primary leptomeningeal melanomatosis. Chemotherapy was started, but general clinical conditions progressively worsened and patient died 11 months after diagnosis. Molecular investigations were performed post-mortem on tumor tissue and revealed absence of BRAF^V600E, GNAQ^Q209 and GNA11^Q209 mutations but the presence of a NRAS^Q61K mutation.

Conclusions

Our case adds some information to the limited experience of the literature, confirming the presence of the NRAS^Q61K mutation in children with melanomatosis. To our knowledge, this is the first case of leptomeningeal melanocytic neoplasms (LMN) without associated skin lesions to harbor this mutation. Isolated LMN presentation might be insidious, mimicking tuberculous meningitis, and should be suspected if no definite diagnosis is possible or if antitubercular treatment does not result in dramatic clinical improvement. Leptomeningeal biopsy should be considered, not only to confirm diagnosis of LMN but also to study molecular profile. Further molecular profiling and preclinical models will be pivotal in testing combination of target therapy to treat this challenging disease.

A giant hyperostotic parasagittal meningioma in a child with neurofibromatosis type II (a case report and literature review)

Large parasagittal meningiomas, in particular hyperostotic ones, in children are rare and problematic in the differential diagnosis. The literature reports only single clinical cases related to this issue; opinions about the indications, surgical treatment options, and prognosis are contradictory. This paper presents a clinical case of a hyperostotic parasagittal meningioma with intra-extracranial growth in a 10-year-old boy with neurofibromatosis type II significantly worsening the prognosis. We discuss the epidemiological and clinical features of childhood meningiomas and issues of their diagnosis, treatment, and prognosis.

Pediatric Intraparenchymal Meningioma: Case Report and Comparative Review

Intra-axial (intraparenchymal) meningiomas are an extremely rare pathology with only dozens of cases reported. In children, the unusual characteristics of intraparenchymal meningiomas can easily create an atypical preoperative differential. The authors present the case of an otherwise healthy 14-year-old girl presenting with new-onset seizures and an intracranial lesion upon investigation. CT and MRI revealed a lesion both cystic and calcified in nature, residing completely within the brain parenchyma. Upon operative examination, the mass was found to be completely surrounded by cortex and to be of two disparate consistencies. Pathological analysis revealed the mass to be a meningioma. Despite the rarity in children, meningiomas must be kept on the differential for cystic, calcified lesions. The differential diagnosis based on imaging as well as the operative strategy taken are further discussed. In addition, the authors review the current understanding of pediatric meningiomas as compared with adult meningiomas.

Paediatric Primary Pachymeningeal Xanthogranuloma with Scattered Foci Displaying Reticulohistiocytoma-like Features

We report a unique case of a 4-year-old girl with an intriguing fibrohistiocytic tumour. Magnetic resonance imaging scans showed a dural mass of variegated intensity compressing the left occipital pole and apparently extending toward the superior sagittal sinus. Grossly, the cut surface of the surgical specimen was yellow, pale, and soft with reddish kernel-like crusts. Histologically, the yellow areas resembled cholesterol granulomas with widespread coagulative necrosis, cholesterol clefts, powdery calcification, foreign body-type giant cells, and foamy macrophages, while the scattered red spots contained numerous multinucleated giant cells of foreign-body and Touton types, the former with amphophilic to slightly eosinophilic cytoplasm. Immunoperoxidase reactions confirmed the expression of histiocytic markers and vimentin. As far as we know, no tumour displaying these peculiar morphological features has yet been described.

Meningiomas: knowledge base, treatment outcomes, and uncertainties. A RANO review

Evolving interest in meningioma, the most common primary brain tumor, has refined contemporary management of these tumors. Problematic, however, is the paucity of prospective clinical trials that provide an evidence-based algorithm for managing meningioma. This review summarizes the published literature regarding the treatment of newly diagnosed and recurrent meningioma, with an emphasis on outcomes stratified by WHO tumor grade. Specifically, this review focuses on patient outcomes following treatment (either adjuvant or at recurrence) with surgery or radiation therapy inclusive of radiosurgery and fractionated radiation therapy. Phase II trials for patients with meningioma have recently completed accrual within the Radiation Therapy Oncology Group and the European Organisation for Research and Treatment of Cancer consortia, and Phase III studies are being developed. However, at present, there are no completed prospective, randomized trials assessing the role of either surgery or radiation therapy. Successful completion of future studies will require a multidisciplinary effort, dissemination of the current knowledge base, improved implementation of WHO grading criteria, standardization of response criteria and other outcome end points, and concerted efforts to address weaknesses in present treatment paradigms, particularly for patients with progressive or recurrent low-grade meningioma or with high-grade meningioma. In parallel efforts, Response Assessment in Neuro-Oncology (RANO) subcommittees are developing a paper on systemic therapies for meningioma and a separate article proposing standardized end point and response criteria for meningioma.

Management of pediatric intracranial meningiomas: an analysis of 31 cases and review of literature

OBJECTIVE

The purpose of this study is to understand the epidemiology, clinical features, behavior, and the prognostic factors that influence the outcome of intracranial meningiomas in children.

METHODS

Thirty-one patients with age less than 18 years who underwent surgery for intracranial meningiomas during the period of at 1988-2012 at Voluntary Health Services Hospital, Chennai, India were studied. These formed 3.7 % of the total 831 cases of intracranial meningiomas operated at the institute.

RESULTS

The study group included 22 (71 %) males and 9 (29 %) females. The mean age of presentation was 15 years, with the youngest being 9 months old. Two (6 %) had evidence of neurofibromatosis type 2 (NF2). The most common symptoms at presentation were seizures in 11 (35.5 %), weakness of limbs in 11 (35.5 %), and raised intracranial pressure in 10 (32 %). Convexity meningiomas were seen in 16 (51 %) and skull base in 15(49 %). Multiple meningiomas was seen in two (6 %) of the patients and intraventricular location was found in one patient (3 %). Two (6 %) had evidence of NF2. Gross total excision was achieved in 26 (83 %) and subtotal excision in 5 (17 %). WHO grade I was found in 20 (64 %) and higher grade was seen in 11 (36 %). The mean follow-up was 46.2 months. Recurrence was seen in 20 patients (64 %). In patients with higher grade or with recurrence resurgery and radiotherapy was given. Three (9 %) had multiple recurrences. On a mean follow-up of 46.2 months, 25 patients (81 %) were neurologically intact, 5 (16 %) were having moderated disability, and 1 (3 %) patient died.

CONCLUSIONS

Childhood meningiomas are uncommon lesions with a slight male predominance. They can have a varied clinical presentation. Higher grade is found more frequently compared with adults. Gross total resection is the goal and in higher grade meningiomas radiotherapy helps as a good adjuvant. Though the rate of recurrence is high, resurgery and radiotherapy gives a good outcome.

Pediatric meningiomas: a single-center experience with 15 consecutive cases and review of the literature

OBJECTIVE

The goal of this study was to determine the epidemiology, clinical presentation, associated factors, pathological features, and treatment outcome of pediatric meningiomas in a single-center institution.

METHODS

Clinical data of 15 patients under 18 years of age operated on for meningiomas from January 1994 to December 2010 were reviewed.

RESULTS

The study group included nine males and six females (mean age of 13 years at surgery). The most common symptoms at presentation were headaches in 6 out of 15 (40 %), raised intracranial pressure in 3 out of 15 (20 %), and seizures in 3 out of 15 (20 %). Sole operated tumors were found in 12 out of 15 (80 %), whose location is as follows: parasagittal in 4 out of 12 (33.3 %), 2 in the convexity (16.6 %), 2 at the skull base (16.6 %), and 4 in other sites (33.3 %). Six children presented with radiation-induced (RT) meningiomas and five had evidence of neurofibromatosis type 2 (NF2). Three patients had multiple meningiomas (all of them had NF2). Simpson's grade I excision was achieved in 12 out of 15 (80 %). On histopathology, 11 out of 15 (73.3 %) were grade I and 4 out of 15 (26.6 %) were grade II (all of them atypical). Five tumors (33.3 %) recurred, four of which had RT or NF2. During the mean follow-up period of 5 years, 12 out of 15 (80 %) had a good outcome (GOS=5).

CONCLUSIONS

Childhood meningiomas are uncommon lesions with a slight male predominance. Absence of large series with long follow-up precludes any definite conclusions on the clinical course and outcome of these tumors. Associated factors (such as RT and NF2), location, and extent of excision appear to be more important than histopathological grade in predicting outcome.

Primary cerebellar histiocytic sarcoma in a 17-month-old girl

The authors report on a case of histiocytic sarcoma (HS) in a pediatric patient presenting with a solitary tumor in the cerebellum, with the aim of providing insight into primary HS in the CNS, which is especially rare. A 17-month-old Japanese girl presented with a 2-week history of progressive gait disturbance. Brain MRI revealed a 4.7 × 4.3 × 4.3-cm well-demarcated solitary mass in the right hemisphere of the cerebellum, initially suggestive of medulloblastoma, ependymoma, or anaplastic astrocytoma. On intraoperative inspection the cerebellar tumor showed intensive dural attachment and was subtotally removed. Histological and immunohistochemical findings were consistent with HS. The patient subsequently received chemotherapy, and her preoperative neurological symptoms improved. Primary HS in the CNS usually demonstrates an aggressive clinical course and is currently considered to have a poor prognosis. The possibility of this rare tumor should be included in the differential diagnosis of localized cerebellar tumors in the pediatric age group.

Neuroimaging of pediatric posterior fossa tumors including review of the literature

Conventional, anatomical MRI is an essential tool for diagnosis and evaluation of location, quality, and extent of posterior fossa tumors, but offers limited information regarding tumor grade and type. Advanced MRI techniques such as diffusion weighted imaging (DWI) and diffusion tensor imaging (DTI) may improve the specific diagnosis of brain tumors in the posterior fossa in children. In this review the conventional neuroimaging findings, as well as the DWI, and DTI characteristics of common pediatric posterior fossa tumors are discussed and summarized.

Meningiomas

OPINION STATEMENT

Meningiomas are extra-axial dural-based tumors. They are the most common intracranial tumors, occur in mid to late life, and have a female predilection. Symptoms are a function of location. Meningiomas are usually benign, but atypical and malignant forms exist. Treatment is indicated for symptomatic lesions or when neurologic symptoms may shortly occur. Surgical resection can be curative; however, because of their location, some lesions are amenable only to partial resection. Radiation therapy is used for incompletely removed symptomatic lesions, lesions that are not surgically accessible, and small symptomatic lesions. For higher grade meningiomas, radiation is used after surgery. For lesions that recur or grow despite surgery and radiation, systemic chemotherapy can be tried. There is no optimal agent, but hydroxyurea is used most often with very modest success; hormonal approaches have not been successful. Targeting somatostatin receptors or receptor tyrosine kinases using novel agents appears to have some activity and is an area of clinical research.

Intracranial meningiomas of atypical (WHO grade II) histology

Atypical (WHO grade II) meningiomas occupy an intermediate risk group between benign (WHO grade I) and anaplastic (WHO grade III) meningiomas. Although grade II meningiomas have traditionally been recognized in only about 5% of cases, after changes in diagnostic criteria with the current 2007 WHO standards, they now comprise approximately 20-35% of all meningiomas. Given the magnitude of this change, much work is now needed to solidify the adoption of these standards, to render inter-observer and inter-institutional comparisons more uniform, and to more carefully define the incidence of grade II histology. However, it is clear that they carry a several-fold increased risk of recurrence, as well as an increased rate of mortality. We will discuss the definition, diagnosis, and treatment of patients with atypical meningioma; review the current phase II cooperative trials; and draw attention to some questions timely for pre-clinical and clinical research.

Meningiomas in children: A study of 18 cases

BACKGROUND

Intracranial meningiomas are rare tumors in children accounting for 0.4-4.6% of all primary brain tumors in the age group of 0-18 years.

OBJECTIVE

To retrospectively analyze the epidemiological profile, clinical features, radiological findings, type of excision, histopathological findings, and overall management profile of these patients.

MATERIALS AND METHODS

Eighteen consecutive cases of meningioma in patients under 18 years of age admitted and operated at our institute between the years 1974-2005 were included in this study.

RESULTS

The mean age of patient at presentation to our hospital was 12.81 years. The male to female ratio was 1.57:1. The median preoperative duration of symptoms was 1.2 years. An increased incidence was seen in patients with neurofibromatosis. Intraventricular and skull base locations were common. Total tumor excision was achieved in all cases.

CONCLUSION

A higher incidence of atypical and aggressive meningiomas is seen in children. Children with complete resection and a typical benign histology have a good prognosis.

Childhood and adolescent meningiomas: a report of 38 cases and review of literature

BACKGROUND

The aim is to study the clinical, radiological and pathological features of childhood and adolescent meningiomas and analyse outcome prognosticators.

METHOD

A retrospective analysis of the case records of patients less than 20 years of age operated for a meningioma in our institute since 1982 was performed. The variables analysed included age, sex, presentation, associated neurofibromatosis (NF), imaging characteristics, extent of resection and histopathology.

RESULTS

The study group included 20 males and 18 females with a mean age of 15.53 years. Eleven children (28.9%) had evidence of NF of whom three had NF2 with bilateral vestibular schwannomas. The common presenting symptoms were seizures (76.3%), raised intracranial tension (71%), and focal neurological deficits (39.4%). The location of the operated tumours were as follows: ten skull base (24.4%), ten falx/parasagittal (24.4%), eight spinal (19.5%), five convexity (12.2%), three posterior fossa (7.3%), three intraventricular (7.3%) and two optic nerve sheath (4.9%). Two children (4.9%) had cystic meningiomas. Grade I excision was achieved only in twenty tumours (48.8%). On histopathology, thirty (73.2%) were grade I, nine (21.9%) were grade II and two (4.9%) were grade III meningiomas. Seven tumours recurred of which six were located at the skull base. During the mean follow up period of 4.74 years, the majority, 32 (84.2%) had a good outcome and five (13.2%) had a poor outcome. One child (2.6%) expired due to post-operative sepsis.

CONCLUSION

Childhood meningiomas are uncommon but not rare lesions with a marginal male predominance. Absence of large series with long follow up precludes any definite conclusions on the clinical course and outcome. Uniform observations made in different series including ours, include a higher incidence of the skull base location and tumours with atypical histopathology. Favourable prognostic factors include younger age (< than 10 years), superficial location, total excision and absence of neurofibromatosis. Location and extent of excision appear to be more important than histopathology grade in predicting outcome.

Posterior fossa clear cell meningioma without dural attachment in a child

INTRODUCTION

Meningiomas are relatively uncommon in childhood. They represent 1% to 2% of all intracranial tumours of infancy and childhood and 1.5% to 1.8% of all intracranial meningiomas. Occasionally, meningiomas may develop without dural attachment. Clear cell meningioma is a histological distinctive uncommon variant of meningioma that may behave aggressively with local recurrence and progression as well as cerebrospinal fluid-borne metastasis. Meningiomas near the craniocervical junction represent challenging tumours, requiring special considerations because of the vicinity of the medulla oblongata, the lower cranial nerves and the vertebral artery.

CASE REPORT

In this study, the authors present a rare case of posterior fossa clear cell meningioma without dural attachment in a child with severe brainstem and cervical spinal cord displacement and discuss the clinical and radiological features as well as treatment considerations.

Meningioma with dural venous sinus invasion and jugular vein extension

Meningiomas represent the most common benign intracranial neoplasm in adults, with a considerably lower incidence in children. The authors present the case of an intracranial meningioma with invasion of, and intraluminal extension into, the transverse and sigmoid sinuses, jugular bulb, and internal jugular vein, resulting in venous occlusion in a 14-year-old girl. Computed tomography scanning, MR imaging, and conventional angiography were performed preoperatively. The patient underwent a 2-stage resection: the supratentorial component was resected first, and the infratentorial and venous sinus and jugular vein components were subsequently removed using a combined skull base approach. Gross-total resection was achieved by opening the lateral dural sinus and removing the meningioma from within the transverse and sigmoid sinuses, the jugular bulb, and the internal jugular vein. The patient remained neurologically intact after the staged tumor resections. Postoperative imaging confirmed the gross-total resection. This case illustrates the unusual property of an intracranial meningioma to invade the intrasinusoidal space and extend into the jugular vein without adherence to the underlying venous endothelium of the jugular vein.

Third ventricular chordoid meningioma in a child

Meningiomas are rare in children. Chordoid meningioma is a very rare variant, as only 16 cases in children have been reported. The authors report the first case of a chordoid meningioma in the third ventricle. A 12-year-old boy presented with headache, abnormal behaviors, and ataxia. Brain MR imaging revealed a 2-cm, well-enhanced mass in the third ventricle and hydrocephalus. Positron emission tomography with [18F]fluorodeoxyglucose showed that the mass was hypermetabolic. Gross-total removal of the mass was performed using a left frontal transcortical and transventricular approach. The mass originated from the left caudate head and was connected to the choroid plexus. A chordoid meningioma was diagnosed on the basis of the histological characteristics of the tumor, which was composed of cords and nests of eosinophilic vacuolated cells with an abundant myxoid matrix, similar to the features of a chordoma. A typical focal meningiomatous pattern was observed. The tumor cells were immunoreactive for vimentin and epithelial membrane antigen. The patient's headache and gait disturbance improved after the tumor was removed. The tumor showed no signs of recurrence during 12 months of follow-up.

Central lactic acidosis, hyperventilation, and respiratory alkalosis: leading clinical features in a 3-year-old boy with malignant meningeal melanoma

Meningeal tumors are extremely rare in children and are diagnostically as well as therapeutically challenging. Among the least common types of malignancies in childhood is malignant melanoma, counting for less than 1% of pediatric tumors. Due to the rarity and the wide spectrum of appearance, initial clinical features may be misleading. A 3-year-old boy was referred to our hospital with symptoms of hyperventilation, dyspnoea, tachycardia, respiratory alkalosis, inarticulate speech, and fatigue. Measurement of pH in cerebrospinal fluid (CSF) yielded central lactic acidosis despite alkalosis in peripheral blood. Diagnostic imaging procedures as well as histology and immunohistochemistry revealed the diagnosis of a malignant meningeal melanoma. We hypothesize that central lactate production of the tumor nests might have induced central acidification, thus inducing hyperventilation by stimulation of central chemoreceptors. This case is a model example of the key role of central pH as an inducer/suppressor of ventilation in humans and illustrates the critical importance of central pH for regulating both ventilation and acid-base homeostasis. Thus, pH of CSF should be measured whenever a malignant brain tumor is suspected.

Pediatric intracranial meningiomas--do they differ from their counterparts in adults?

AIM

Meningiomas are very rare in children comprising only 0.44.1% of pediatric age tumors and only 1.5-1.8% of all intracranial neoplasms. We analyzed the clinical, pathological and management profile of these rare tumors and elucidated their differences from meningiomas in adults.

METHODS

From 1990 to 2005, 33 patients belonging to the pediatric age group with intracranial meningiomas were treated in NIMHANS.

RESULTS

There were 19 male and 14 female children. The duration of symptoms ranged from 1 to 60 months. The study had a mean follow-up of 23.4 months. The commonest presenting symptoms were headache (90.9%) and visual disturbances (51.5%). Three patients had associated neurofibromatosis. Calcification was noticed in 22% of the tumors. Intraventricular meningiomas were the commonest (24.2%). Gross total or near total resection was possible in 22 out of 33 patients. Nine patients had reversible postoperative motor deficits. Fibrous meningioma was the commonest histological subtype (24.2%). Five patients had atypical or anaplastic subtypes. Adjuvant radiotherapy was administered in 4 patients. Six patients had recurrences and underwent surgery. Ten patients required either staged procedures or multiple surgeries for the recurrence/residual tumors.

CONCLUSION

Pediatric meningiomas are rare tumors and differ from those in adults by their male predominance, atypical locations, higher rates of malignant subtypes, recurrence and association with neurofibromatosis. Surgical management is challenging because of atypical location.

Meningiomas in children

OBJECTIVE

Pediatric meningioma is a rare diagnosis. This retrospective review seeks to elucidate pertinent characteristics of pediatric patients presenting with meningioma.

METHODS

The Seattle Children's Hospital and Regional Medical Center brain tumor database was surveyed from 1940 through 2004. Twenty patients were identified.

RESULTS

The median age of the 20 patients was 13 years. Five patients had radiation-induced meningiomas. Five patients had neurofibromatosis type 2. Ten patients had spontaneously arising meningiomas, 2 of which were malignant.

CONCLUSION

Patients with spontaneously arising meningiomas were younger than those with identified risk factors. There was no recurrence in patients with radiation-induced meningiomas. The only death occurred in a patient with a malignant meningioma.

Primary intra-diploic meningioma in a child

BACKGROUND

Primary intra-diploic meningiomas are uncommon in childhood and, at the clinical onset, may be confused with other and more frequent bone tumours because they lack specific clinical and radiological characteristics. Surgery is indicated not only to remove the lesion but also to obtain an accurate histological diagnosis.

CASE REPORT

We report the case of a young girl who presented with a recently developed subcutaneous hard mass in the left pterional region. Neuroradiological investigations revealed an intra-osseous lytic mass with a sclerotic reaction. Diagnosis was possible only after the total removal of the tumour and its histological examination.

Role of radiation therapy in treating intracranial meningiomas

Surgery is the mainstay for many patients with meningiomas, and it remains the standard. In large single-institution series, gross-total resection has been reported to achieve 5-, 10-, and 15-year recurrence-free survival rates of approximately 90, 80, and 70%, respectively. There are a growing number of series of patients with prolonged follow-up in which authors have evaluated fractionated external-beam radiation therapy (EBRT) either as an adjuvant to surgery for subtotally resected, recurrent, or higher-grade meningiomas, or as an alternative to surgery. The primary focus of this review is EBRT, but to lend perspective, a comparative analysis of surgery and radiosurgery is also provided.

Meningioangiomatosis with meningioma: an uncommon association of a rare entity--report of a case and review of the literature

INTRODUCTION

Meningioangiomatosis (MA) is a rare lesion, probably of malformative origin, consisting of meningovascular proliferation and leptomeningeal calcification. Patients with MA usually present with seizures or persistent headaches. Neurofibromatosis may be associated in a variable proportion of patients, while in others it may be sporadic. Surgical treatment is usually recommended, and is gratifying in most cases. Rarely, MA has been described coexisting with meningiomas, arteriovenous malformations, encephaloceles, oligodendrogliomas, meningeal haemangiopericytomas and orbital erosion. Among these, meningiomatosis with meningioma is the most frequent combination.

CASE REPORT

We report a case of MA with meningioma in an 18-month-old girl, who presented with recurrent seizures.

DISCUSSION

In these situations, it is extremely important for the pathologist to be aware of this entity and to distinguish it from other lesions, like cortical invasion by a meningioma, intraparenchymal meningioma and intracerebral schwannoma, which it may mimic.

Clear cell meningioma: case report and review of the literature

Clear cell meningioma (CCM) is a rare variant of meningioma. Only 17 cases have been previously reported in children. Although it has bland cytologic features, it has a higher rate of recurrence than does conventional meningioma. This variant has been reported in sites such as spinal/intradural (lumbar and thoracic), cerebellopontine angle, and supratentorial. The differential diagnosis of CCM includes microcystic meningioma, hemangioblastoma, and clear cell ependymoma. The characteristic histology and immunohistochemistry leads to the diagnosis. We present a case of a 7-year-old boy with a CCM of the cauda equina and a review of pediatric CCM.

Insights into meningioangiomatosis with and without meningioma: a clinicopathologic and genetic series of 24 cases with review of the literature

Meningioangiomatosis (MA) is a rare seizure-associated lesion of presumed hamartomatous or developmental origin. It is occasionally combined with a neoplasm, most commonly meningioma (MA-M). In the current study, we examined 24 cases (14 pure MA, 10 MA-M) using immunohistochemistry for merlin, protein 4.1 B, progesterone receptor (PR), and MIB-1, as well as FISH for NF2 and 4.1B gene dosages. Nine cases of MA-M (90%) had gene deletions (NF2/4.7B), protein losses (merlin/protein 4.1B), and/or PR positivity, with a similar or identical phenotype in both components. No PR positivity or gene deletions were seen in pure MAs, though merlin and/or protein 4.1B were immunonegative in six cases. Our data suggest that in most MA-Ms, the MA component is neoplastic, likely representing an exuberant perivascular pattern of spread from the meningioma, rather than an underlying hamartoma. This pattern of spread may be facilitated by meningiomas that are predominantly leptomeningeal or intracerebral in origin. It remains important to distinguish this pattern from true brain invasion, given the more ominous prognostic significance of the latter. In contrast, most perivascular spindled cells of pure MA are genetically and immunohistochemically similar to non-neoplastic meningothelial cells, consistent with current histogenetic theories.

Molecular pathogenesis of meningiomas

Meningiomas are common central nervous system tumors that originate from the meningeal coverings of the brain and the spinal cord. Most meningiomas are slowly growing benign tumors that histologically correspond to World Health Organization (WHO) grade I. However, certain rare histological variants (clear cell, chordoid, papillary, and rhabdoid), as well as atypical (WHO grade II) and anaplastic (WHO grade III) meningiomas show a more aggressive biological behavior and are clinically associated with a high risk of local recurrence and a less favorable prognosis. This review summarizes the most important features of meningioma pathology and provides an up-to-date overview about the molecular mechanisms involved in meningioma initiation and progression. Current data indicate that meningioma initiation is closely linked to the inactivation of one or more members of the highly conserved protein 4.1 superfamily, including the neurofibromatosis type 2 gene product merlin/schwannomin, protein 4.IB (DAL-1) and protein 4.1R. The genetic alterations in atypical meningiomas are complex and involve losses on 1p, 6q, 10, 14q and 18q, as well as gains on multiple chromosomes. The relevant genes are still unknown. Anaplastic meningiomas show even more complex genetic alterations, including frequent alteration of the CDKN2A, p14ARF, and CDKN2B tumor suppressor genes at 9p21, as well as gene amplification on 17q23. A better understanding of the molecular mechanisms involved in meningioma pathogenesis may not only lead to the identification of novel diagnostic and prognostic marker but will also facilitate the development of new pathogenesis-based therapeutic strategies.