Histological-subtypes and anatomical location correlated in meningeal brain tumors (meningiomas)

Hyperostosis in meningioma: a retrospective exploration of histological correlates

PURPOSE

Meningiomas are the most common type of primary brain tumour. Hyperostosis is commonly associated but remains incompletely understood. This study aimed to evaluate the relationship between meningioma-associated hyperostosis and other tumour variables.

MATERIALS AND METHODS

We retrospectively analysed 245 patients with 263 cranial meningiomas (202 CNS WHO grade 1, 53 grade 2, and 8 grade 3) who underwent surgery over a three-year period. Meningiomas adjacent to the skull were included. Demographic, radiological, and tumour characteristics were analysed using standard statistical methods.

RESULTS

Hyperostosis was evident in 99 (38%) of meningiomas. The most common subtypes were meningothelial, transitional, fibrous, atypical, and anaplastic. There were no statistically significant relationships between hyperostosis and bone invasion, and CNS WHO grade and histological subtype. Hyperostosis was more common in skull base meningiomas than in convexity meningiomas (p = 0.001). Ki-67 index was significantly related to CNS WHO grade but not histological subtype when grade was considered. Mean Ki-67 index was higher in meningiomas without hyperostosis (p = 0.03). There was no such relationship with bone invasion (p = 0.29). Univariate and multivariate analysis revealed that Ki-67 index was negatively correlated with hyperostosis (p = 0.03), while bone invasion (p < 0.001) and skull base location (p = 0.03) were positively correlated with hyperostosis.

CONCLUSIONS

Hyperostosis did not appear to be related to CNS WHO grade or histological subtype. Proliferative activity appeared to be higher in meningiomas without hyperostosis and hyperostosis was associated with evidence of bone invasion and skull base location.

Clear cell meningiomas-case presentation, review of radiographic identifiers, and treatment approaches

Spinal clear cell meningiomas (CCMs) are a rare histological subtype of meningiomas that pose preoperative diagnostic challenges due to their radiographic similarities with other lesions. They are also more aggressive, exhibiting higher rates of recurrence, particularly in pediatric patients. Overcoming diagnostic challenges of these tumors can improve patient outcomes. In this report, we describe a case of a pediatric patient presenting with a lumbar CCM in whom we were able to obtain gross total resection. Our report reviews previously identified predictors of CCM recurrence, including the Ki-67 proliferation index, number of spinal segments involved, and hormonal influences related to age and sex. We describe the characteristic radiographic features that differentiate spinal CCMs from other tumors to improve pre-operative diagnosis. Furthermore, we provide our rationale for adjuvant therapy for pediatric patients to refine treatment protocols for these rare tumors.

Intracranial meningiomas at a tertiary hospital: Spectrum of MRI findings with histopathologic correlation

Background

Intracranial meningiomas consist of a heterogenous group of histological subtypes, some of which are rare. Data that may play an important role in neurosurgical decision-making regarding the incidence and MRI features of these histological subtypes in the South African population groups, are lacking.

Objectives

This study aimed to assess the spectrum of MRI findings and histological subtypes of meningiomas in the South African context, with the goal of improving the paucity of literature on the topic.

Method

A retrospective review of the MRI features of 41 cases of histologically confirmed intracranial meningiomas was performed at a tertiary hospital level. Imaging features were audited and correlated with histological subtypes during statistical analysis.

Results

Eleven different histological subtypes of meningioma were encountered. World Health Organization (WHO) Grade I meningothelial meningiomas were the most common histological subgroup. Overall, meningiomas were found to be predominantly isointense to grey matter on T1-weighted imaging, irrespective of the histological subtype, with greater signal variability on T2-weighted imaging. Morphologies of specific subtypes are in keeping with the literature.

Conclusion

Analysis of this series of intracranial meningiomas did not demonstrate statistically significant differences in MRI features between histological subtypes to allow for accurate preoperative prediction of meningioma subtype or WHO grade. This highlights the importance of definitive histopathological diagnosis rather than over-reliance on presumed benign imaging features.

Contribution

This original research article discusses the impact of histological subtype on the MRI appearance of intracranial meningiomas, with the aim to improve the paucity of literature on the subject in the context of the South African population.

Liquid biopsy evaluation of circulating tumor DNA, miRNAs, and cytokines in meningioma patients

Introduction

Liquid biopsy is a non-invasive method used to detect cancer and monitor treatment responses by analyzing blood or other bodily fluids for cancer biomarkers. Meningiomas are the most common primary central nervous system tumors, and biomarkers play a crucial role in their diagnosis, prognosis, and treatment monitoring. The World Health Organization (WHO) classifies meningiomas based on tumor grades and molecular alterations in genes such as in NF2, AKT1, TRAF7, SMO, PIK3CA, KLF4, SMARCE1, BAP1, H3K27me3, TERT promoter, and CDKN2A/B. Liquid biopsy, specifically cell-free DNA (cfDNA) analysis, has shown potential for monitoring meningiomas as it can detect ctDNA release in the blood, unaffected by the blood-brain barrier. MicroRNAs (miRNAs) have also been found to be deregulated in various cancers, including meningiomas, presenting potential as diagnostic biomarkers. Additionally, studying cytokines in the tumor microenvironment may aid in establishing prognostic or diagnostic panels for meningiomas.

Methods

In the present study we analyzed the DNA coming from both the plasma and tumor samples, in addition to analyze miRNA-21 and cytokines in the plasma of 28 meningioma patients.

Discussion and Conclusion

Our findings indicate that the detection of ctDNA in the plasma of meningioma patients is feasible. However, it's important to note that certain challenges persist when comparing plasma DNA analysis to that of tumor tissues. In our study, we observed a paired identification of mutations in only one patient, highlighting the complexities involved. Furthermore, we successfully identified miR-21 and cytokines in the plasma samples. Notably, our analysis of Interleukin 6 (IL-6) unveiled higher expression in the clear cell subtype compared to the other types. Despite the ongoing research, the clinical implementation of liquid biopsy in meningiomas remains somewhat limited. Nevertheless, our promising results underscore the need for further investigation.

Intracranial intricacies: Comprehensive analysis of rare skull base meningiomas-A single-center case series

This study paper's main goal is to report rare cases of skull base meningiomas that exemplify the complexities of diagnosis, therapy, and postoperative care. By describing these rare cases, we hope to advance knowledge of the clinical signs, difficulties, and prognoses of skull base meningiomas in a challenging anatomical setting. In the posterior cranial fossa, our investigation reveals a unique example of skull base meningioma that involved numerous cranial nerves and complex vasculature. A variety of visual abnormalities were present in the patient's clinical presentations, highlighting the wide range of symptoms that these tumors might cause depending on their precise positions. These cases highlight the critical importance of preoperative imaging, including high-resolution MRI and angiography, as well as the diagnostic difficulties these tumors pertain. By reporting these instances, our research adds to the body of knowledge about skull base meningiomas and offers insightful information about the nuances of their therapies. Our findings highlight the importance of individualized treatment plans, interdisciplinary cooperation, and the demand for continued study to better comprehend these convoluted tumors. Such studies are essential for advancing our knowledge of these enigmatic tumors, guiding clinical judgment, and eventually improving patient outcomes. These findings are important because they can fill information gaps, improve treatment plans, and encourage additional research in neuro-oncology.

Abstract

This study presents a series of three rare cases of skull base meningiomas, emphasizing the complexities in diagnosis, treatment, and postoperative care. The patients' clinical presentations and imaging highlighted the diverse symptoms and challenges associated with these tumors, found in intricate anatomical locations. The cases underscore the crucial role of preoperative high-resolution imaging and angiography in diagnostic accuracy. Surgical intervention, guided by a multidisciplinary approach, is pivotal in managing these demanding cases. Histopathological examinations confirmed atypical meningiomas. The postoperative phases involved meticulous care to ensure optimal recovery and functional outcomes. Our findings contribute to the understanding of skull base meningiomas, emphasizing the need for personalized treatment plans and ongoing research to improve patient outcomes in neuro-oncology.

Variability in the Arterial Supply of Intracranial Meningiomas: An Anatomic Study

BACKGROUND AND OBJECTIVES

Intracranial meningiomas are a diverse group of tumors, which vary by grade, genetic composition, location, and vasculature. Expanding the understanding of the supply of skull base (SBMs) and non-skull base meningiomas (NSBMs) will serve to further inform resection strategies. We sought to delineate the vascular supply of a series of intracranial meningiomas by tumor location.

METHODS

A retrospective study of intracranial meningiomas that were studied using preoperative digital subtraction angiograms before surgical resection at a tertiary referral center was performed. Patient, tumor, radiologic, and treatment data were collected, and regression models were developed.

RESULTS

One hundred sixty-five patients met inclusion criteria. The mean age was 57.1 years (SD: 12.6). The mean tumor diameter was 4.9 cm (SD: 1.5). One hundred twenty-six were World Health Organization Grade I, 37 Grade II, and 2 Grade III. Arterial feeders were tabulated by Al-Mefty's anatomic designations. SBMs were more likely to derive arterial supply from the anterior circulation, whereas NSBMs were supplied by external carotid branches. NSBMs were larger (5.61 cm vs 4.45 cm, P = <.001), were more often presented with seizure (20% vs 8%, P = .03), were higher grade ( P = <.001) had more frequent peritumoral brain edema (84.6% vs 66%, P = .04), and had more bilateral feeders (47.7% vs 28%, P = .01) compared with SBMs. More arterial feeders were significantly associated with lower tumor grade ( P = .023, OR = 0.59). Higher tumor grade (Grade II/III) was associated with fewer arterial feeders ( P = .017, RR = 0.74).

CONCLUSION

Meningioma location is associated with specific vascular supply patterns, grade, and patient outcomes. This information suggests that grade I tumors, especially larger tumors, are more likely to have diverse vascular supply patterns, including internal carotid branches. This study may inform preoperative embolization and surgical considerations, particularly for large skull base tumors.

Recurrent Meningothelial Meningioma With Multiple Extensions: A Complex Case Study

This case report presents a comprehensive analysis of a 67-year-old patient diagnosed in 2017 with meningothelial meningioma, focusing on the challenges of managing such tumors and their neurological implications. Meningiomas, being the most common benign intracranial neoplasms, have a notable research gap regarding their association with seizures and motor deficits. This patient, who had a history of depressive disorder, persistent cephalalgia syndrome, and ataxic gait, initially presented with symptoms including ataxic gait, confusion, and headache. Imaging revealed a large, hyperdense right frontal meningioma with a significant mass effect. Following surgical resection, the patient experienced notable neurological improvement. However, in 2023, the patient re-presented with bradypsychia, bradykinesia, and memory disorders, indicating a recurrent meningioma. This case exemplifies the recurrence and complex management of meningiomas, particularly in elderly patients, and highlights the importance of individualized treatment strategies. Surgical resection remains the primary treatment approach, supplemented by radiotherapy in cases of recurrence or incomplete resection. The case underscores the need for advancements in therapeutic approaches to mitigate recurrence risks and enhance patient outcomes in meningioma management. This is especially pertinent given the tumor's predilection for older females and its varied neurological manifestations, such as ataxic gait and seizures.

Robotic Stereotactic Radiotherapy for Intracranial Meningiomas-An Opportunity for Radiation Dose De-Escalation

OBJECTIVE

To evaluate the possibility of dose de-escalation, with consideration of the efficacy and safety of robotic stereotactic CyberKnife radiotherapy in patients diagnosed with intracranial meningiomas.

METHODS

The study group consisted of 172 patients (42 men and 130 women) treated in III Radiotherapy and Chemotherapy Clinic of Maria Sklodowska-Curie National Research Institute of Oncology in Gliwice between January 2011 and July 2018. The qualification for dose de-escalation was based on MRI (magnetic resonance imaging) features: largest tumor diameter less than 5 cm, well-defined tumor margins, no edema, and no brain infiltration. The age of patients was 21-79 years (median 59 years) at diagnosis and 24-80 years (median 62 years) at radiotherapy. Sixty-seven patients (Group A) were irradiated after initial surgery. Histopathological findings were meningioma grade WHO 1 in 51 and WHO 2 in 16 cases. Group B (105 patients) had no prior surgery and the diagnosis was based on the typical features of meningioma on MRI. All patients qualified for the robotic stereotactic CyberKnife radiotherapy, and the total dose received was 18 Gy in three fractions to reference isodose 78-92%.

RESULTS

Follow-up period was 18 to 124 months (median 67.5 months). Five- and eight-year progression free survival was 90.3% and 89.4%, respectively. Two patients died during the follow-up period. Progression of tumor after radiotherapy was registered in 16 cases. Four patients required surgery due to progressive disease, and three of them were progression free during further follow-up. Twelve patients received a second course of robotic radiotherapy, 11 of them had stable disease, and one patient showed further tumor growth but died of heart failure. Crude progression free survival after both primary and secondary treatment was 98.8%. Radiotherapy was well-tolerated: acute toxicity grade 1/2 (EORTC-RTOG scale) was seen in 10.5% of patients. We did not observe any late effects of radiotherapy.

CONCLUSION

Stereotactic CyberKnife radiotherapy with total dose of 18 Gy delivered in three fractions showed comparable efficacy to treatment schedules with higher doses. This could support the idea of dose de-escalation in the treatment of intracranial meningiomas.

Automated segmentation of meningioma from contrast-enhanced T1-weighted MRI images in a case series using a marker-controlled watershed segmentation and fuzzy C-means clustering machine learning algorithm

INTRODUCTION AND IMPORTANCE

Accurate segmentation of meningiomas from contrast-enhanced T1-weighted (CE T1-w) magnetic resonance imaging (MRI) is crucial for diagnosis and treatment planning. Manual segmentation is time-consuming and prone to variability. To evaluate an automated segmentation approach for meningiomas using marker-controlled watershed segmentation (MCWS) and fuzzy c-means (FCM) algorithms.

CASE PRESENTATION AND METHODS

CE T1-w MRI of 3 female patients (aged 59, 44, 67 years) with right frontal meningiomas were analyzed. Images were converted to grayscale and preprocessed with Otsu's thresholding and FCM clustering. MCWS segmentation was performed. Segmentation accuracy was assessed by comparing automated segmentations to manual delineations.

CLINICAL DISCUSSION

The approach successfully segmented meningiomas in all cases. Mean sensitivity was 0.8822, indicating accurate identification of tumors. Mean Dice similarity coefficient between Otsu's and FCM1 was 0.6599, suggesting good overlap between segmentation methods.

CONCLUSION

The MCWS and FCM approach enables accurate automated segmentation of meningiomas from CE T1-w MRI. With further validation on larger datasets, this could provide an efficient tool to assist in delineating meningioma boundaries for clinical management.

Atypical radiological aspect of meningioma: Web-like enhancement

Meningiomas are the most common extra-axial neoplasmof the central nervous system (CNS). There are a number of characteristic imaging features of meningiomas on magnetic resonance imaging (MRI) that allow an accurate diagnosis, however there are a number of atypical features that may be diagnostically challenging. Furthermore, a number of other neoplastic and non-neoplastic conditions may mimic meningiomas. This case highlights the importance of careful analysis of imaging findings and the need for consideration of all possible diagnoses, including rare or atypical presentations of common neoplasms such as meningiomas. Early detection and accurate diagnosis are crucial in determining the appropriate management and improving the outcomes for patients with intracranial tumors.

Primary extracranial meningioma of maxilla- A case report

Meningiomas represent one of the commonest benign neural tissue neoplasms, but it is an extremely rare finding in the oral cavity. It tends to arise from the arachnoid cap cells pertaining to dura matter of the Meninges, the choroid plexus, or the brain stem. Herein, we report the case of a 36-year-old male patient, who visited our Department with the chief complaint of facial swelling associated with asymmetry. Based on thorough clinical, radiological, histopathological and immunohistochemical analyses, a diagnosis of Primary Extracranial Meningioma (PEM) of the Maxilla was made. Later, the tumor was surgically removed, and on follow up, the patient is doing well. Our presented case is extremely unique-it represents a PEM involving the oral cavity.

Review of meningioma diagnosis and management

Meningiomas are the most common intracranial tumors in adult patients. Although the majority of meningiomas are diagnosed as benign, approximately 20% of cases are high-grade tumors that require significant clinical treatment. The gold standard for grading central nervous system tumors comes from the World Health Organization Classification of Tumors of the central nervous system. Treatment options also depend on the location, imaging, and histopathological features of the tumor. This review will cover diagnostic strategies for meningiomas, including 2021 updates to the World Health Organization's grading of meningiomas. Meningioma treatment plans are variable and highly dependent on tumor grading. This review will also update the reader on developments in the treatment of meningiomas, including surgery, radiation therapy and monoclonal antibody treatment.

Preoperative Apparent Diffusion Coefficient Values for Differentiation between Low and High Grade Meningiomas: An Updated Systematic Review and Meta-Analysis

The meta-analysis aimed to compare the preoperative apparent diffusion coefficient (ADC) values between low-grade meningiomas (LGMs) and high-grade meningiomas (HGMs). Medline, Cochrane, Scopus, and Embase databases were screened up to January 2022 for studies investigating the ADC values of meningiomas. The study endpoint was the reported ADC values for LGMs and HGMs. Further subgroup analyses between 1.5T and 3T MRI scanners, ADC threshold values, ADC in different histological LGMs, and correlation coefficients (r) between ADC and Ki-67 were also performed. The quality of studies was evaluated by the quality assessment of diagnostic accuracy studies (QUADAS-2). A χ2-based test of homogeneity was performed using Cochran’s Q statistic and inconsistency index (I2). Twenty-five studies with a total of 1552 meningiomas (1102 LGMs and 450 HGMs) were included. The mean ADC values (×10−3 mm2/s) were 0.92 and 0.79 for LGMs and HGMs, respectively. Compared with LGMs, significantly lower mean ADC values for HGMs were observed with a pooled difference of 0.13 (p < 0.00001). The results were consistent in both 1.5T and 3T MRI scanners. For ADC threshold values, pooled sensitivity of 69%, specificity of 82%, and AUC of 0.84 are obtained for differentiation between LGMs and HGMs. The mean ADC (×10−3 mm2/s) in different histological LGMs ranged from 0.87 to 1.22. Correlation coefficients (r) of mean ADC and Ki-67 ranged from −0.29 to −0.61. Preoperative ADC values are a useful tool for differentiating between LGMs and HGMs. Results of this study provide valuable information for planning treatments in meningiomas.

Case Report: Creeping Growth in Lymphoplasmacyte-Rich Meningioma-A Radiologic Variant

Lymphoplasmacyte-rich meningioma (LRM) is a rare histologic subtype of meningioma. Creeping-growth pattern is uncommon in meningioma, and the mechanism is unclear. Here, we report a 44-year-old man presented with extremities weakness for 2 months and incontinence for 2 weeks. Head and neck MRI revealed diffuse creeping-growth nodular meningeal masses with skull base, tentorium, sella area, and C1-6 vertebral plane involvement. An operation was carried out, cervical and lower clivus part of the lesion was resected, but gross total resection could not be achieved due to the widespread lesions. Pathologic examination revealed the diagnosis of LRM. The patient is free from progression clinically 3 months postoperatively. We also conducted a systematic literature review about LRM with creeping-growth pattern. A total of only nine cases (including the present case) of creeping-growth LRMs were included and analyzed in terms of clinical manifestations, radiological features, treatment, and outcome. LRMs show a higher rate (7.5%) of creeping-growth pattern than other types of meningiomas. The average creeping length of all creeping-growth LRMs was 11.4 ± 10.9 cm (range, 3–30 cm). Most cases (66.7%) had obvious peritumoral edema. Total removal rate is low (33.3%), and two of them (22.2%) received biopsy, followed by steroids treatment (or further immunosuppressive drugs therapy) and radiotherapy. The recurrence rate is higher than conventional LRMs (22.2 vs. 11.3%), and one patient (11.1%) died 11 months after treatment. Creeping-growth pattern in LRM may be considered as a general radiologic variant. The recurrence rate is higher compared with LRM with round/swelling pattern. We speculated that the pathogenesis of creeping growth in LRM may be associated with damage of lymphatic systems of the central nervous system.

Intraosseous metaplastic meningioma: A case report

Metaplastic meningioma is a rare World Health Organization Grade I meningioma subtype, accounting for 0.2%-1.6% of all meningiomas. Primary extradural meningiomas represent less than 2% of all meningiomas, with intraosseous meningioma as a subtype of primary extradural meningiomas. Herein, we report the case of a 65-year-old male presenting with headache. His computed tomography scans showed an osteolytic left parietal bone mass, and magnetic resonance imaging revealed hyperintense dots in the mass on T1-weighted images. The mass was then resected and diagnosed on histopathological examination as an intraosseous metaplastic meningioma.

Histopathological Correlation (World Health Organization Classification) of Meningiomas and Their Anatomical Localization: A Multicenter Epidemiological Study in Mexico

OBJECTIVE

To determine the epidemiology of the localization and histological type of meningiomas in the Mexican population and the distribution of the different histological patterns and their relationship to tumor localization and patient demographics.

METHODS

A retrospective analysis was performed in 5 hospitals in Mexico from 2009 to 2019. For qualitative variables, mean values were compared using Pearson χ² test for the correlation between location and histological pattern as well as the clinical presentation and the patient's sex. Student t test was performed for age and its correlation with location and histology.

RESULTS

Analysis of 179 patients revealed significant differences in histopathological pattern, patient sex, and tumor location. No significant differences were found for age or clinical presentation in association with any specific histological pattern.

CONCLUSIONS

There was a correlation between the histology of the 15 histopathological varieties of meningiomas and the predilection site of appearance as well as certain demographic aspects, such as sex. This study lays the foundation for future studies in Mexico on the differentiation and typing of meningiomas regardless of the histological grade to which they belong, as the exact behavior of these tumors, including grade I tumors, remains unknown to date.

Texture Analysis in Brain Tumor MR Imaging

Texture analysis, as well as its broader category radiomics, describes a variety of techniques for image analysis that quantify the variation in surface intensity or patterns, including some that are imperceptible to the human visual system. Cerebral gliomas have been most rigorously studied in brain tumors using MR-based texture analysis (MRTA) to determine the correlation of various clinical measures with MRTA features. Promising results in cerebral gliomas have been shown in the previous MRTA studies in terms of the correlation with the World Health Organization grades, risk stratification in gliomas, and the differentiation of gliomas from other brain tumors. Multiple MRTA studies in gliomas have repeatedly shown high performance of entropy, a measure of the randomness in image intensity values, of either histogram- or gray-level co-occurrence matrix parameters. Similarly, researchers have applied MRTA to other brain tumors, including meningiomas and pediatric posterior fossa tumors.

However, the value of MRTA in the clinical use remains undetermined, probably because previous studies have shown only limited reproducibility of the result in the real world. The low-to-modest generalizability may be attributed to variations in MRTA methods, sampling bias that originates from single-institution studies, and overfitting problems to a limited number of samples.

To enhance the reliability and reproducibility of MRTA studies, researchers have realized the importance of standardizing methods in the field of radiomics. Another advancement is the recent development of a comprehensive assessment system to ensure the quality of a radiomics study. These two-way approaches will secure the validity of upcoming MRTA studies. The clinical use of texture analysis in brain MRI will be accelerated by these continuous efforts.

Clinical Outcome and Recurrence After Meningioma Surgery: An Experience from a Developing Country, Nepal

BACKGROUND

Meningioma is the most common primary brain tumor, constituting more than half of all benign central nervous system tumors. This study aims to analyze the clinical outcome and recurrence after surgery of intracranial meningioma in Nepal.

METHODS

This is a retrospective study of newly diagnosed intracranial meningioma patients operated at Nepal Mediciti Hospital between 2007 and 2019. Demographics; clinical, radiologic, and perioperative details; histopathology; and clinical outcome variables were reviewed. Association of independent variables with primary outcome variables: modified Rankin Scale (favorable [≤ 3] vs. unfavorable [>3]) and recurrence was analyzed. Logistic regression model was designed to calculate adjusted odds ratio with 95% confidence interval (CI).

RESULTS

Of 233 patients, mean age was 47 years, female individuals were affected twice as much as male individuals. Location was supratentorial in 83.3%, 83.7% had tumor greater than 5 cm in size. Gross total resection (SM 0-III) was achieved in 85.4%. A total of 98.7% had grade I meningioma. Favorable outcome was found in 94.8%. Recurrence rate was 6.9%. Tumor size less than 3 cm (adjusted odds ratio [AOR] 0.024 95% CI 0.001-0.416, P = 0.010), gross total resection (AOR 19.737, 95% CI 4.69-83.063, P < 0.001), and comorbidity (AOR 0.202, 95% CI 0.052-0.785, P = 0.021) were significantly associated with favorable outcome whereas age (AOR 3.491, 95% CI 1.029-11.850, P = 0.045) and WHO grade (AOR 0.024, 95% CI 0.002-0.344, P = 0.006) were independently associated with recurrence. The complication and surgical mortality rates were 30% and 1.72%, respectively.

CONCLUSIONS

Tumor size, extent of resection, age, tumor grade, and medical comorbidities were significantly associated with postoperative outcome. We recommend a prospective study with standardized follow up protocol to assess the long-term outcome.

High HMGA2 expression without gene rearrangement in meningiomas

High mobility group AT-hook 2 (HMGA2) is a non-histone transcriptional regulator protein. Aberrant expression of the HMGA2 gene (HMGA2) and structural rearrangement at the chromosomal region 12q14 with HMGA2 involvement have been reported in several mesenchymal tumors. We analyzed truncated and full-length HMGA2 expression in 55 cases of meningioma, the most common brain tumor of mesenchymal origin. Fluorescence in situ hybridization and 3'-rapid amplification of cDNA ends were used to investigate the possibility of gene rearrangements. Moreover, the relationship between HMGA2 expression and clinicopathological features was assessed. Compared with normal brain tissues, 95% of the meningioma tissues exhibited increased HMGA2 expression. In 14 cases, the expression of truncated HMGA2 was more than two-fold higher than that of paired full-length HMGA2. Chromosomal translocation involving the chromosomal region 12q14 was undetectable. No significant correlation was found between the Ki-67 labeling index and HMGA2 expression and between the HMGA2 expression and the clinicopathological features. The majority of the meningioma cases displayed increased HMGA2 expression, which was not attributed to the chromosomal rearrangement at the corresponding region. Similar to that in the other mesenchymal tumors, increased HMGA2 expression was not associated with tumor cell proliferation in meningiomas.

Recurrence/Regrowth in Grade I Meningioma: How to Predict?

The HLA-G and HLA-E molecules, Ki67, progesterone (PR), estrogen (ER) and androgen receptors (AR), p53, COX-2, and HER2 were studied to assess whether the biological behavior of grade I meningiomas is related to their expression. Tissue samples from 96 patients with grade I intracranial meningiomas were analyzed by immunohistochemistry on tissue microarray blocks (TMA) using antibodies specific for HLA-G, HLA-E, Ki67, PR, ER, AR, p53, COX-2, and HER2. Meningiomas were classified as small (≤2 cm, 1.0%), medium (>2 and ≤4 cm, 32.3%), and large (>4 cm, 66.7%). Tumor size was not related to recurrence/regrowth (p = 0.486), but was significantly correlated with peritumoral edema (p = 0.031) and intratumoral calcifications (p = 0.018). Recurrent meningiomas were observed in 14.6% of cases. Immunostaining for each marker was: HLA-G 100%; HLA-E 95.6%; PR 62%; ER 2.1%; AR 6.5%; p53 92.6%; COX-2 100%; HER2 0%; Ki67, mean 2.61 ± 2.29%, median 2.1%. Primary and recurrent meningiomas showed no significant relation with HLA-E and hormone receptors (p > 0.05), except for Ki67, where a higher median was observed in recurrent tumors than in primary (p = 0.014). The larger the tumor, the more severe the peritumoral edema, and the greater the presence of calcifications. Ki67 appears to be a good biomarker of recurrence/regrowth in grade I meningiomas.

Imaging spectrum of meningiomas: a review of uncommon imaging appearances and their histopathological and prognostic significance

Meningiomas are the most common primary non-glial intracranial neoplasms. In most cases, meningiomas have typical imaging appearances and locations, enabling a straightforward radiological diagnosis. However, a myriad of unusual appearances potentially complicate the imaging picture. Furthermore, certain imaging features can also predict the specific histopathological nature and WHO grade of the meningioma. 'Typical' meningiomas include meningothelial, fibrous, and transitional variants and have the characteristic imaging features described for meningiomas. Several 'atypical' variants exist, which, although less common, also generally have a less favourable prognosis and necessitate early diagnosis. In addition, meningiomas can occur in a variety of unusual intracranial and even extra-cranial locations and need to be distinguished from the more common tumours of these regions on imaging. Any associated oedema or haemorrhagic changes may alter the prognosis and have to be carefully assessed and reported. Cystic changes in meningiomas have been divided into five subtypes, and accurate characterisation is essential to predict the prognosis. An extensive review of the several possible variations in imaging appearances of meningiomas including the differential features of common and uncommon variants would facilitate informative radiological reporting of meningiomas. This would be expected to improve pre-operative planning prior to surgical biopsy and thereby improve disease prognosis and patient outcomes.

Evaluation of Epidemiologic Factors, Radiographic Features, and Pathologic Findings for Predicting Peritumoral Brain Edema in Meningiomas

BACKGROUND

Despite several treatment options that are available for meningiomas, surgery is the only method currently practiced. Peritumoral brain edema (PTBE) in meningiomas causes difficulty marginalizing the dissection in an intraoperative setting.

PURPOSE

To evaluate whether the epidemiological variables, imaging characteristics, and pathologic parameters are correlated with the presence of PTBE in meningiomas.

STUDY TYPE

Retrospective study from 2015 to 2018.

SUBJECTS

In all, 550 patients with histopathologically confirmed meningioma were included. After exclusion of patients with extradural, spinal, and intraventricular meningiomas and those with image artifacts, a total of 441 patients were included in the final analysis.

FIELD STRENGTH/SEQUENCE

Images were performed with 3T MR scanners and axial/sagittal T₁ WI, axial/coronal T₂ WI and axial/sagittal/coronal contrast-enhanced T₁ WI after administration of 0.1 mmol/kg of body weight of Gd-DTPA.

ASSESSMENT

Fourteen variables were patients' age, sex, skull changes, calcification, density, location, margin, volume, cerebrospinal fluid (CSF) cleft, signal intensity (SI) on T₂ WI, degree and pattern of contrast enhancement, WHO histological classification, and Ki-67 labeling index.

STATISTICAL TESTS

The relationship between each factor and the formation of PTBE was examined by multivariate logistic regression analysis.

RESULTS

After multivariate logistic regression, the absence of CSF cleft (odds ratio [OR]: 63.43, 95% confidence interval [CI]: 27.24-121.42, P = 1.2 × 10^-8 ), non-skull base location (OR: 15.32, 95% CI: 5.81-28.23, P = 0.0008), high SI on T₂ WI (OR: 5.05, 95% CI: 2.27-14.88, P = 0.01), and G I uncommon subtypes (OR: 4.75, 95% CI: 1.42-15.94, P = 0.01) were found to be significant independent factors associated with the occurrence of PTBE in meningiomas. In patients with PTBE-positive meningiomas, there was no significant correlation between the volume of PTBE and the volume of the tumor (r = 0.17, P = 0.60).

DATA CONCLUSION

These factors may be suggestive of anticipating the formation of PTBE.

LEVEL OF EVIDENCE

3 Technical Efficacy Stage: 3 J. Magn. Reson. Imaging 2020;52:174-182.

WHO grade, proliferation index, and progesterone receptor expression are different according to the location of meningioma

BACKGROUND

Meningiomas may show a different WHO grade and variable biological and clinical behaviors. The aim of the present study is to assess whether WHO grade, proliferation index, progesterone receptor (PR) expression, histological subtype, neuroradiological features, and the recurrence rate differ depending on the tumor location.

METHODS

Three hundred meningiomas operated on from 2006 to 2016 were reviewed. The WHO grade (2007 classification), Ki67-MIB1, progesterone receptor expression, and histological subtype were reexamined and correlated to the meningioma location, classified as medial skull base, lateral skull base, non-skull base, and spinal.

RESULTS

Non-skull base and lateral skull base meningiomas showed significantly higher rates of atypical WHO II forms (34% and 25.5% respectively) than medial skull base (12.5%) and spinal ones (7%) (p = 0.0003) and also higher rates of tumors with Ki67-Li > 4% (42% and 38% vs 22% and 14%) (p = 0.0031). The rate of meningiomas with PR expression ≤ 50% was significantly lower in medial skull base (25%) than in non-skull base (48%) (p = 0.009). Meningothelial and transitional meningiomas were more frequent at the skull base (68.5% and 54.5%, respectively), the fibroblastic subtype at the non-skull base (48.5%), and the psammomatous at the spinal canal (50%) (p < 0.00001). Medial skull base and spinal meningiomas showed significantly lower size (p < 0.00001), lower rates of cases with lost arachnoid interface (p = 0.0022), and significantly lower recurrence rates (p = 0.0035) than lateral skull base and non-skull base meningiomas.

CONCLUSION

Medial skull base meningiomas show lower size, lower rate of atypical forms, lower Ki67-Li values, and significantly higher PR expression than those at the lateral skull base and non-skull base. This corresponds to lesser aggressiveness and lower recurrence rates.

Petroclival meningiomas: radiological features essential for surgeons

Petroclival meningiomas (PCMs) have always been a challenge for surgeons because of their difficult anatomical location. The role of radiology in providing precise indications regarding the tumour site and aggressiveness plays a major part in guiding the subsequent therapeutic process. The purpose of this review is to provide a set of the main radiological features helpful in the management of PCMs towards the most correct therapeutic approach.

We aim to offer a radiological overview to allow the patient to be directed to surgery with the least possible risk of complications.

Neurosurgical treatment and outcome patterns of meningioma in Sweden: a nationwide registry-based study

Background

Surgery is the main treatment modality for intracranial meningiomas, but data on short-term surgical outcome are limited. The aim of this Swedish nationwide registry-based study was to benchmark the 30-day complication rate in a cohort of meningioma patients using data from the Swedish brain tumor registry (SBTR). Furthermore, we investigated outcomes for asymptomatic patients.

Methods

Data were collected from the SBTR for all adults with histopathologically verified intracranial meningioma between 2009 and 2015. Patient symptoms, tumor characteristics, and complications within 30 days postoperatively were analyzed.

Results

In total, 2324 patients, with a mean age of 58.7 years (SD 13.5), underwent surgery for intracranial meningioma and 14.1% of the patients were asymptomatic before the intervention. The most common symptom prior to treatment was focal deficit, which occurred in 1450 patients (62.4%). Moreover, within 30 days after surgery, 344 patients (14.8%) developed new neurological deficits and new-onset seizures occurred in 105 patients (4.5%), while 8.3% of asymptomatic patients developed neurological deficit and 3.7% new-onset seizures. Due to complications, reoperations were performed in 120 patients (5.2%). The postoperative 30-day mortality in the whole cohort was 1.5%.

Conclusion

This study benchmarks the 30-day complication rate after meningioma surgery and provides outcome data in the highly relevant group of asymptomatic patients using data from the Swedish brain tumor registry. Since surgical decision-making is a careful consideration of short-term risk versus long-term benefit, this information may be useful for both caregivers and patients.

Analysis of Minichromosome Maintenance-2 (MCM-2) and Cyclin D1 Expression in Meningioma

World Health Organization histopathological grading of meningioma is associated with recurrence and clinical outcome. Grade II meningioma can be difficult to distinguish with grade I especially in case in which mitosis is not easily identified. MCM-2 and Cyclin D1 play crucial role in cell cycle and have been reported overexpressed in many malignant tumors. The aim of this observational analytic study was to analyze the differences and correlation between MCM-2 and Cyclin D1 in various meningioma grading. Immunohistochemystry with MCM-2 and Cyclin D1 was performed on 25 paraffin blocks of grade I, II and III meningiomas at the Laboratory of Anatomical Pathology, Dr. Soetomo Hospital. The immunoexpression are evaluated using Labelling Index, then analyzed statistically. The results showed significant difference in expression of MCM-2 within various meningioma grading (p=0.000) and significant difference in expression of Cyclin D1 within grade I and II also within grade I and III (p<0.050), but not in grade II and III (p>0.050). There was also positive correlation between MCM-2 and Cyclin D1 expression in various meningioma grading (rs=0.683, p=0.000). MCM-2 may play role in distinguishing various meningioma grading. Cyclin D1 can distinguish grade I and II also grade I and III, but not grade II and III. Overexpression MCM-2 was along with Cyclin D1 in various meningioma gradings.

Tumour stem cells in meningioma: A review

Meningioma is a common intracranial and intraspinal neoplasm accounting for 25-30% of all primary neurological tumours. It is associated with high rates of recurrence especially in higher-grade tumours and lesions located at the skull base. Cancer stem cells are increasingly recognised as the origin of cancer and are attributed to loco-regional recurrence, metastasis and treatment resistance. This review presents the accumulating evidence of the presence of tumour stem cells within meningioma and the stem cell markers being used to characterise this putative primitive population within this common tumour.

Sellar and Parasellar Imaging

The skull base is a complex anatomical region that harbors many important neurovascular structures in a relatively confined space. The pathology that can develop at this site is varied, and many disease processes may present with similar clinical and neuroimaging findings. While computed tomography maintains a role in the evaluation of many entities and can, for instance, delineate osseous erosion with great detail and characterize calcified tumor matrices, magnetic resonance imaging (MRI) is the mainstay in the neuroimaging assessment of most pathology occurring at the skull base. Various MRI sequences have proven to be robust tools for tissue characterization and can provide information on the presence of lipids, paramagnetic and diamagnetic elements, and tumor cellularity, among others. In addition, currently available MRI techniques are able to generate high spatial resolution images that allow visualization of cranial nerves and their involvement by adjacent pathology. The information obtained from such examinations may aid in the distinction of these disease processes and in the accurate delineation of their extent prior to biopsy or treatment planning.

Somatic AKT1 mutations cause meningiomas colocalizing with a characteristic pattern of cranial hyperostosis

Somatic genetic mutations in meningiomas are associated with histologic subtypes, anatomical location, and grade. Concomitant hyperostosis occurs with some meningiomas and the pathogenesis is not well understood. Cranial hyperostosis and meningiomas are common in patients with Proteus syndrome, which is caused by a somatic activating mutation in AKT1 c.49G>A. This same mutation has also been found in 6-9% of sporadic non-syndromic meningiomas. Sixty-one patients with Proteus syndrome meeting clinical diagnostic criteria were evaluated at the NIH from 1997 to 2014. Of these 61, 52 had a somatic activating mutation (c.49G>A, p.Glu17Lys) in AKT1 confirmed from affected tissue samples. Photographs, physical examination and/or autopsy, X-rays, CT, and/or MRI scan of the head were reviewed in 29/52 patients. Of the 29 patients, the most common intracranial tumor was meningioma, all co-localizing with cranial hyperostosis, and diagnosed at younger ages than typical for isolated, non-syndromic meningiomas. These patients had progressive cranial overgrowth that consisted primarily of diploic space expansion, and was characterized by unilateral, parasagittal, and frontal bone involvement. We hypothesize that sporadic meningothelial and transitional subtype meningiomas are a forme fruste or microform of Proteus syndrome, and activation of the AKT/PI3K pathway drives hyperostosis in both non-syndromic, and Proteus-related meningiomas. © 2016 The Authors. American Journal of Medical Genetics Part A Published by Wiley Periodicals, Inc.

Variants of meningiomas: a review of imaging findings and clinical features

Meningiomas are common neoplasms that frequently occur in the brain and spine. Among the 15 histological subtypes of meningiomas in the WHO classification, the incidence of meningothelial meningiomas is the highest, followed by fibrous and transitional meningiomas. These three subtypes account for approximately 80 % of all meningiomas, and thus could be regarded as typical meningiomas. For this reason, other uncommon histological subtypes may be considered as imaging variants, and diagnosis is often challenging for radiologists solely based on imaging features of typical meningiomas. In addition to the histological subtypes, meningiomas arising in atypical locations could be easily mistaken for other lesions more commonly observed in those locations. The purpose of this article is to review characteristic clinical and imaging findings of uncommon meningiomas, including histological variants and meningiomas occurring in relatively rare locations.

Cavernous sinus syndrome: need for early diagnosis

Cavernous sinus syndrome (CSS) is a rare condition characterised by ophthalmoplegia, proptosis, ocular and conjunctival congestion, trigeminal sensory loss and Horner's syndrome. These signs and symptoms result from the involvement of the cranial nerves passing through the cavernous sinus. We report the case of a 53-year-old man with a history of daily stabbing headache associated with dizziness, progressive blurred vision, right ocular pain, ptosis and ophthalmoplegia. After working up the patient, a meningioma was identified as the cause of the CSS. Despite advances in neuroimaging techniques, in some cases, the aetiology of CSS remains difficult to determine. We highlight the clinical and radiological features of a meningioma, one of the causes of CSS. Early diagnosis and treatment of CSS play a key role in a better prognosis.