Relationship between tumor location, size, and WHO grade in meningioma

Acute subdural hematoma caused by hemorrhagic falx meningioma: A case report and review of the literature

We herein report a case of acute subdural hematoma caused by hemorrhagic falx meningioma. The patient was a 64-year-old woman with no significant medical history or prior history of trauma. She experienced a sudden onset of headache and weakness in her extremities. Computed tomography (CT) scan and magnetic resonance imaging (MRI) showed a mass lesion with intratumoral hemorrhage or faint calcification along the left side of the fronto-parietal cerebral falx. There was also a linear lesion at the left side of the falx, suggesting acute subdural hematoma. MRI was performed again on the eleventh day. On precontrast T1-weighted images, intratumoral hemorrhage and widespread left subdural hematoma were shown as high intensity. On postcontrast T1-weighted images, the tumor showed heterogeneous enhancement with a dural tail sign on the falx, indicative of a falx meningioma. She underwent surgical resection, and the histological subtype was transitional meningioma. Nine cases of hemorrhagic falx meningioma associated with acute subdural hematoma have been reported. If not limited to the site of occurrence, there have been 59 reported cases overall. In our investigation, the incidence of hemorrhage is higher in the convexity and lower in the skull base. It is higher for fibrous, angiomatous, and metaplastic subtypes and lower for meningothelial subtype. The location and histological subtype might be risk factors for meningioma associated with subdural hematoma. Further accumulation of cases will be necessary to establish the cause of bleeding.

A comprehensive correlation of the KI-67 proliferation index to patient´s, imaging and tumor features and its value in predicting long-term course of patients with newly diagnosed intracranial meningiomas

To analyze the correlation of KI-67-Proliferation Index (KI-67-PI) with preoperative patients and MRI characteristics, WHO grading, histological subtype and long-term-course of patients with newly diagnosed intracranial meningiomas (IM). In this single-center retrospective study, all consecutive patients with IM were analyzed from January 2007 to August 2019. Patient´s demographics (age, sex), imaging parameters (location, volume, edema, necrosis), and tumor features (WHO grade, histology) were assessed and correlated with KI-67-PI. Long-term data were retrieved from patient's last follow-up visits. This study included 463 IM in 457 surgically treated patients. Males exhibited a higher KI-67-PI than females (7.31 ± 0.22 vs. 5.37 ± 0.53; p < 0.01, Mann-Whitney U Test). Age positively correlated with KI-67-PI in both sexes (p < 0.01, Spearman), with older patients having a higher KI-67-PI. KI-67-PI was significantly higher in convexity IM compared to frontobasal IM (7.15 ± 5.56 vs. 4.66 ± 2.94; p < 0.05, ANOVA, Tukey´s HSD), while no difference in KI-67-PI expression was found when other locations were compared to each other (Tukey´s HSD). Higher KI-67-PI was significantly correlated with larger tumor volume (p < 0.01, Spearman), larger tumor necrosis and larger peritumoral edema (p < 0.01, Kruskal-Wallis). Patients with recurrent IM had a significantly higher KI-67-PI than patients without recurrence (8.24 ± 5.88 vs. 5.14 ± 3.53; p < 0.01, ANOVA, Tukey´s HSD) during a mean follow-up period of 80.92 ± 38.1 months. Atypical and anaplastic IM exhibited significantly higher KI-67-PI compared to all other WHO grade 1 histological subtypes (12.09 ± 0.73 vs. 4.51 ± 0.13; p < 0.01, Kruskal-Wallis test) and KI-67-PI was significantly higher in anaplastic IM compared to atypical meningioma (19.67 ± 1.41 vs. 11.01 ± 0.38; p < 0.01, ANOVA). Higher KI-67-PI is not only associated with atypical and anaplastic subtypes of IM, but is also significantly higher in males, positively correlates with patients age, larger tumor volume, lager peritumoral edema and necrosis on preoperative MRI and predicts tumor recurrence. Therefore, KI-67-PI may serve as a decision indicator for adjuvant treatment in patients with IM.

The Evolving Classification of Meningiomas: Integration of Molecular Discoveries to Inform Patient Care

Meningioma classification and treatment have evolved over the past eight decades. Since Bailey, Cushing, and Eisenhart's description of meningiomas in the 1920s and 1930s, there have been continual advances in clinical stratification by histopathology, radiography and, most recently, molecular profiling, to improve prognostication and predict response to therapy. Precise and accurate classification is essential to optimizing management for patients with meningioma, which involves surveillance imaging, surgery, primary or adjuvant radiotherapy, and consideration for clinical trials. Currently, the World Health Organization (WHO) grade, extent of resection (EOR), and patient characteristics are used to guide management. While these have demonstrated reliability, a substantial number of seemingly benign lesions recur, suggesting opportunities for improvement of risk stratification. Furthermore, the role of adjuvant radiotherapy for grade 1 and 2 meningioma remains controversial. Over the last decade, numerous studies investigating the molecular drivers of clinical aggressiveness have been reported, with the identification of molecular markers that carry clinical implications as well as biomarkers of radiotherapy response. Here, we review the historical context of current practices, highlight recent molecular discoveries, and discuss the challenges of translating these findings into clinical practice.

Single versus multiple reoperations for recurrent intracranial meningiomas

PURPOSE

To identify the risk factors and management of the multiple recurrences and reoperations for intracranial meningiomas.

METHODS

Data of a neurosurgical series of 35 patients reoperated on for recurrent intracranial meningiomas were reviewed. Analyzed factors include patient age and sex, tumor location, extent of resection, WHO grade, Ki67-MIB1 and PR expression at initial diagnosis, time to recurrence; pattern of regrowth, extent of resection, WHO grade and Ki67-MIB1 at first recurrence were also analyzed. All these factors were stratified into two groups based on single (Group A) and multiple reoperations (Group B).

RESULTS

Twenty-four patients (69%) belonged to group A and 11 (31%) to group B. The age < 65 years, male sex, incomplete resection at both initial surgery and first reoperation, and multicentric-diffuse pattern of regrowth at first recurrence are risk factors for multiple recurrences and reoperations. In group B, the WHO grade and Ki67-MIB1 increased in further recurrences in 54% and 64%, respectively. The time to recurrence was short in 7 cases (64%), whereas 4 patients (36%) further recurred after many years. Eight patients (73%) are still alive after 7 to 22 years and 2 to 4 reoperations.

CONCLUSION

The extent of resection and the multicentric-diffuse pattern of regrowth at first recurrence are the main risk factors for multiple recurrences and reoperations. Repeated reoperations might be considered even in patients with extensive recurrent tumors before the anaplastic transformation occurs. In such cases, even partial tumor resections followed by radiation therapy may allow long survival in good clinical conditions.

Recurrence and Mortality Rate in a 42 Patient Cohort of Giant Meningiomas

BACKGROUND

Giant meningiomas may show special features in terms of biological behavior and management. We aimed to research recurrence and mortality of giant meningiomas.

METHODS

Medical files of patients with meningioma with at least 1 dimension of ≥5 cm in any plane in radiological investigations between December 2012 and January 2022 were retrospectively reviewed. Tumor dimensions were measured on magnetic resonance images except 1. All patients except two underwent clinical follow-up at a mean of 27.19 ± 29.87 (range, 4-112) months.

RESULTS

There were 42 patients, 26 (61.9%) women and 16 (38.1%) men who ranged in age from 31 to 85 (mean, 60.31 ± 14.86) years. Headache (57.1%) was the most common symptom. The mean tumor size was 70.14 ± 19.03 (range, 50-152) mm. Tumors were most located at the frontal convexity (40.5%). Simpson grade I resection was achieved in 19% of the cases. The tumors were World Health Organization grade 1 in 74% and grade 2 in 26% of the cases. Major complications developed in 26.1% of the patients. Recurrence happened in 5 (11.9%) cases. The number of World Health Organization grade 2 tumors (P = 0.013; P < 0.05) and tumor size (P = 0.006; P < 0.01) were significantly higher in the recurrent cases. Mortality was % 11.9 and statistically significantly higher in the recurrence group (P = 0.025; P < 0.05).

CONCLUSIONS

Giant intracranial meningiomas are challenging because of surgical experience, tumor size, peritumoral edema, blood supply, anatomical changes, and limited visibility. They have a high risk of recurrence and mortality.

Multi-parametric MRI-based machine learning model for prediction of WHO grading in patients with meningiomas

OBJECTIVE

The purpose of this study was to develop and validate a nomogram combined multiparametric MRI and clinical indicators for identifying the WHO grade of meningioma.

MATERIALS AND METHODS

Five hundred and sixty-eight patients were included in this study, who were diagnosed pathologically as having meningiomas. Firstly, radiomics features were extracted from CE-T1, T2, and 1-cm-thick tumor-to-brain interface (BTI) images. Then, difference analysis and the least absolute shrinkage and selection operator were orderly used to select the most representative features. Next, the support vector machine algorithm was conducted to predict the WHO grade of meningioma. Furthermore, a nomogram incorporated radiomics features and valuable clinical indicators was constructed by logistic regression. The performance of the nomogram was assessed by calibration and clinical effectiveness, as well as internal validation.

RESULTS

Peritumoral edema volume and gender are independent risk factors for predicting meningioma grade. The multiparametric MRI features incorporating CE-T1, T2, and BTI features showed the higher performance for prediction of meningioma grade with a pooled AUC = 0.885 (95% CI, 0.821-0.946) and 0.860 (95% CI, 0.788-0.923) in the training and test groups, respectively. Then, a nomogram with a pooled AUC = 0.912 (95% CI, 0.876-0.961), combined radiomics score, peritumoral edema volume, and gender improved diagnostic performance compared to radiomics model or clinical model and showed good calibration as the true results. Moreover, decision curve analysis demonstrated satisfactory clinical effectiveness of the proposed nomogram.

CONCLUSIONS

A novel nomogram is simple yet effective in differentiating WHO grades of meningioma and thus can be used in patients with meningiomas.

CLINICAL RELEVANCE STATEMENT

We proposed a nomogram that included clinical indicators and multi-parameter radiomics features, which can accurately, objectively, and non-invasively differentiate WHO grading of meningioma and thus can be used in clinical work.

KEY POINTS

• The study combined radiomics features and clinical indicators for objectively predicting the meningioma grade. • The model with CE-T1 + T2 + brain-to-tumor interface features demonstrated the best predictive performance by investigating seven different radiomics models. • The nomogram potentially has clinical applications in distinguishing high-grade and low-grade meningiomas.

Patterns of failure after radiosurgery for WHO grade 1 or imaging defined meningiomas: Long-term outcomes and implications for management

BACKGROUND

We analyzed long-term control and patterns of failure in patients with World Health Organization Grade 1 meningiomas treated with definitive or postoperative stereotactic radiosurgery at the authors' affiliated institution.

METHODS

96 patients were treated between 2004 and 2019 with definitive (n = 57) or postoperative (n = 39) stereotactic radiosurgery. Of the postoperative patients, 17 were treated adjuvantly following subtotal resection and 22 were treated as salvage at time of progression. Patients were treated to the gross tumor alone without margin or coverage of the dural tail to a median dose of 15 Gy. Median follow up was 7.4 years (inter-quartile range 4.8-11.3). Local control, marginal control, regional control, and progression-free survival were analyzed.

RESULTS

Local control at 5 and 10 years was 97 % and 95 %. PFS at 5 and 10 years was 94 % and 90 % with no failures reported after 6 years. Definitive and postoperative local control were similar at 5 (95 % [82-99 %] vs. 100 %) and 10 years (92 % [82-99 %] vs. 100 %). Patients treated with postoperative SRS did not have an increased marginal failure rate (p = 0.83) and only 2/39 (5 %) experienced recurrence elsewhere in the cavity.

CONCLUSIONS

Stereotactic radiosurgery targeting the gross tumor alone provides excellent local control and progression free survival in patients treated definitively and postoperatively. As in the definitive setting, patients treated postoperatively can be treated to gross tumor alone without need for additional margin or dural tail coverage.

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.

A machine learning-based integrated clinical model for predicting prognosis in atypical meningioma patients

PURPOSE

Atypical meningioma (AM) recurs in up to half of patients after surgical resection and may require adjuvant therapy to improve patient prognosis. Various clinicopathological features have been shown to have prognostic implications in AM, but an integrated prediction model is lacking. Thus, in this study, we aimed to develop and validate an integrated prognostic model for AM.

METHODS

A retrospective cohort of 528 adult AM patients surgically treated at our institution were randomly assigned to a training or validation group in a 7:3 ratio. Sixteen baseline demographic, clinical, and pathological parameters, progression-free survival (PFS), and overall survival (OS) were analysed. Sixty-five combinations of machine learning (ML) algorithms were used for model training and validation to predict tumour recurrence and patient mortality.

RESULTS

The random survival forest (RSF) model was the best model for predicting recurrence and death. Primary or secondary tumour, Ki-67 index, extent of resection, tumour size, brain involvement, tumour necrosis, and age contributed significantly to the model. The C-index value of the RSF recurrence prediction model reached 0.8080. The AUCs for 1-, 3-, and 5-year PFS were 0.83, 0.82, and 0.86, respectively. The C-index value of the RSF death prediction model reached 0.8890. The AUCs for 3-year and 5-year OS were 0.88 and 0.89, respectively.

CONCLUSION

A high-performing integrated RSF predictive model for AM recurrence and patient mortality was proposed that may guide therapeutic decision-making and long-term monitoring.

Metastatic meningioma: a case series and systematic review

BACKGROUND

Meningiomas are the most common primary intracranial tumor. While the majority of meningiomas are benign, rarely they can metastasize extracranially. There is a need for a more comprehensive review of these patients to improve our understanding of this rare phenomenon and its prevalence globally. Here we describe our institution's experience of patients presenting with metastatic meningiomas. We further perform a systematic review of the existing literature to explore common features of this rare manifestation of meningioma and review the efficacy of current treatments.

METHODS

We performed a retrospective clinical review of all adult patients with metastatic meningioma managed at our institution over the past 20 years, identifying 6 patients. We then performed a systematic review of cases of metastatic meningioma in the literature ranging from the years 1886 to 2022. A descriptive analysis was then conducted on the available data from 1979 onward, focusing on the grade and location of the primary tumor as well as the latency period to, and location of, the metastasis.

RESULTS

In total, we analyzed 155 cases. Fifty-four percent of patients initially presented with a primary meningioma located in the convexity. The most common site of metastasis was the lung. Risk factors associated with a shorter time to metastasis were male sex and a high initial grade of the tumor. Regarding treatment, the addition of chemotherapy was the most common adjunct to the standard management of surgery and radiotherapy. Despite an exhaustive review we were unable to identify effective treatments. The majority of published cases came from centers situated in high-income countries (84%) while only 16% came from lower- and middle-income countries.

CONCLUSIONS

Metastatic meningiomas pose a pertinent, and likely underestimated, clinical challenge within modern neurosurgery. To optimize management, timely identification of these patients is important. More research is needed to explore the mechanisms underlying these tumors to better guide the development of effective screening and management protocols. However, screening of each meningioma patient is not feasible, and at the heart of this challenge is the inability to control the primary disease. Ultimately, a consensus is needed as to how to correctly screen for and manage these patients; genomic and epigenomic approaches could hold the answer to finding druggable targets.

Differential diagnosis of atypical and anaplastic meningiomas based on conventional MRI features and ADC histogram parameters using a logistic regression model nomogram

The purpose of the study was to determine the value of a logistic regression model nomogram based on conventional magnetic resonance imaging (MRI) features and apparent diffusion coefficient (ADC) histogram parameters in differentiating atypical meningioma (AtM) from anaplastic meningioma (AnM). Clinical and imaging data of 34 AtM and 21 AnM diagnosed by histopathology were retrospectively analyzed. The whole tumor delineation along the tumor edge on ADC images and ADC histogram parameters were automatically generated and comparisons between the two groups using the independent samples t test or Mann-Whitney U test. Univariate and multivariate logistic regression analyses were used to construct the nomogram of the AtM and AnM prediction model, and the model's predictive efficacy was evaluated using calibration and decision curves. Significant differences in the mean, enhancement, perc.01%, and edema were noted between the AtM and AnM groups (P < 0.05). Age, sex, location, necrosis, shape, max-D, variance, skewness, kurtosis, perc.10%, perc.50%, perc.90%, and perc.99% exhibited no significant differences (P > 0.05). The mean and enhancement were independent risk factors for distinguishing AtM from AnM. The area under the curve, accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of the nomogram were 0.871 (0.753-0.946), 80.0%, 81.0%, 79.4%, 70.8%, and 87.1%, respectively. The calibration curve demonstrated that the model's probability to predict AtM and AnM was in favorable agreement with the actual probability, and the decision curve revealed that the prediction model possessed satisfactory clinical availability. A logistic regression model nomogram based on conventional MRI features and ADC histogram parameters is potentially useful as an auxiliary tool for the preoperative differential diagnosis of AtM and AnM.

A Nomogram Model for Stratifying the Risk of Recurrence in Patients with Meningioma After Surgery

BACKGROUND

Here, we aimed to investigate the clinical parameters affecting the recurrence of meningiomas, and to construct a predictive nomogram model, so as to predict the recurrence-free survival (RFS) of meningiomas more accurately.

METHODS

The Clinical, imaging, and pathological data of 155 primary meningioma patients treated surgically from January 2014 to March 2021 were retrospectively analyzed. Independent prognostic factors affecting postoperative recurrence of meningioma were identified by univariate and multivariate Cox regression analyses. A predictive nomogram was established based on independent influence parameters. Subsequently, time-dependent receiver operating characteristic curve, calibration curve, and Kaplan-Meier method were utilized to evaluate the predictive ability of the model.

RESULTS

The multivariate Cox regression analysis showed that tumor size, Ki-67 index, and resection extent had independent prognostic significance, and these parameters were subsequently used to construct a predictive nomogram. Receiver operating characteristic curves indicated that the model was more accurate in predicting RFS than independent factors. Calibration curves suggested that the predicted RFS were similar to the actual observed RFS. In the Kaplan-Meier analysis, the RFS of high-risk cases was obviously shorter than that of low-risk cases.

CONCLUSIONS

The tumor size, Ki-67 index, and extent of resection were independent factors affecting the RFS of meningioma. The predictive nomogram based on these factors can be used as an effective method to stratify the recurrence risk of meningioma and provide a reference for patients to choose personalized treatment.

Conditional Recurrence-Free Survival After Surgical Resection of Meningioma

BACKGROUND

Recurrence after meningioma resection warrants serial surveillance imaging, but little evidence guides the optimal time interval between imaging studies/surveillance duration.

OBJECTIVE

To describe recurrence-free survival (RFS) after meningioma resection, conditioned to short-term RFS.

METHODS

A retrospective cohort study for adults presenting for meningioma resection from 2000 to 2018 was conducted. The primary outcome was postoperative follow-up RFS. Conditional RFS Kaplan-Meier analysis was performed at 1, 2, 3, 5, and 10 years, conditioned to 6-month and 12-month RFS. RFS probabilities conditioned to 6-month RFS were estimated in subgroups, stratified by World Health Organization grade, extent of resection, and need for postoperative radiation.

RESULTS

In total, 723 patients were included. Median age at surgery was 57.4 years (IQR = 47.2-67.2). Median follow-up was 23.5 months (IQR = 12.3-47.8). Recurrence was observed in 90 patients (12%), with median time to recurrence of 14.4 months (IQR = 10.3-37.1). Conditioned to 6-month postoperative RFS, patients had 90.3% probability of remaining recurrence-free at 2 years and 69.4% at 10 years. Subgroup analysis conditioned to 6-month RFS demonstrated grade 1 meningiomas undergoing gross total resection (GTR) had 96.0% probability of RFS at 1 year and 82.8% at 5 years, whereas those undergoing non-GTR had 94.5% and 79.9% probability, respectively. RFS probability was 78.8% at 5 years for non-grade 1 meningiomas undergoing GTR, compared with 69.7% for non-grade 1 meningiomas undergoing non-GTR. Patients with non-grade 1 meningiomas undergoing upfront radiation had a 1-year RFS of 90.1% and 5-year RFS of 51.7%.

CONCLUSION

Recurrence risk after meningioma resection after an initial recurrence-free period is reported, with high-risk subgroups identified. These results can inform objective shared decision-making for optimal follow-up.

Advanced Meningioma Imaging

Noninvasive imaging methods are used to accurately diagnose meningiomas and track their growth and location. These techniques, including computed tomography, MRI, and nuclear medicine, are also being used to gather more information about the biology of the tumors and potentially predict their grade and impact on prognosis. In this article, we will discuss the current and developing uses of these imaging techniques including additional analysis using radiomics in the diagnosis and treatment of meningiomas, including treatment planning and prediction of tumor behavior.

Staged Strategies to Deal with Complex, Giant, Multi-Fossa Skull Base Tumors

Given the complex and multifaceted nature of resecting giant tumors in the anterior, middle, and, to a lesser extent, the posterior fossa, we present two example strategies for navigating the intricacies of such tumors. The foundational premise of these two approaches is based on a two-stage method that aims to improve the visualization and excision of the tumor. In the first case, we utilized a combined endoscopic endonasal approach and a staged modified pterional, pretemporal, with extradural clinoidectomy, and transcavernous approach to successfully remove a giant pituitary adenoma. In the second case, we performed a modified right-sided pterional approach with pretemporal access and extradural clinoidectomy. This was followed by a transcortical, transventricular approach to excise a giant anterior clinoid meningioma. These cases demonstrate the importance of performing staged operations to address the challenges posed by these giant tumors.

Different clinical and cytogenetic features of primary skull base meningiomas and non-skull base meningiomas

PURPOSE

To investigate the different clinical and cytogenetic features of skull base meningiomas (SBMs) and non-SBMs (NSBMs).

METHODS

We conducted a retrospective study on a series of 316 patients with primary intracranial meningiomas. The t-test and the Chi-square test were used to analyze the differences between 194 SBMs and 122 NSBMs. The Cox analysis was used to determine prognostic factors for tumor recurrence.

RESULTS

Compared with NSBMs, on average, the age of patients with SBMs was about 2.88 years younger (p = 0.024); the duration of operation of SBMs was 2.73 h longer (p < 0.001); the duration of hospital stays of patients with SBMs was about 6.76 days longer (p < 0.001); the tumor volume was 7.69 cm³ smaller (p = 0.025); the intraoperative blood loss was 147.61ml more (p = 0.039); the total cost of SBMs was 1.39 times more (p < 0.001); the preoperative KPS, postoperative KPS, and follow-up KPS of patients with SBMs were all respectively lower (p < 0.001); Gross total resection was less achieved (p < 0.001). SBMs (average of 20.80 per sample) had a smaller total number of copy number variations (CNVs) than NSBMs (29.98 per sample) (p = 0.009). Extremely large CNVs (> 5 Mb) were more likely to present in NSBMs (p < 0.001). Cox analysis showed that subtotal resection (p = 0.002) and the total number of CNVs (p = 0.015) were independent risk factors for tumor recurrence.

CONCLUSIONS

The clinical and cytogenetic features of SBMs were different from NSBMs. Moreover, the degree of resection and the total number of whole-genome CNVs were independent prognostic factors for tumor recurrence.

Epidemiology of Intracranial Meningiomas in Mexico: Cohort of the National Institute of Neurology and Neurosurgery During the Last Decade

Introduction Meningiomas have been described as slow-growing neoplasms with benign behavior derived from the connective tissue surrounding the brain and spinal cord. Meningiomas represent one-third of primary central nervous system (CNS) tumors. The World Health Organization (WHO) initially classified them into three groups based on their histopathological characteristics, recently incorporating molecular patterns. Small cohorts have been reported in Latin America compared to the international literature. Ignoring the epidemiology of meningiomas in this region and considering this limitation, we aim to study the epidemiology of meningiomas in our country, Mexico. Material and methods A historical cohort was carried out on 916 patients diagnosed with intracranial meningiomas from January 2008 to January 2021, considering sociodemographic, topographic, and histopathological characteristics. Results In this study, 69.4% (n=636) of patients were women with a mean overall age of 47.53 (SD=14.85) years; 79.6% (n=729) of the lesions were supratentorial with convexity meningiomas being the most prevalent at 32.6% (n=299). Histopathologically, transitional (45.7%) (n=419), meningothelial (22.1%) (n=202), and fibroblastic (16.7%) (n=153) meningiomas were the most frequent. We found significant differences between men and women in age (p=0.01), infra or supratentorial presentation (p<0.001), location of the lesion (p<0.001), and histopathological characteristics (p<0.001). Conclusions Our results are consistent with what has been reported; however, until now, it appears as the largest series reported in our country and Latin America.

SMARCE1-related meningiomas: A clear example of cancer predisposing syndrome

We report the case of a 16-year-old girl presenting with spinal clear-cell multiple meningiomas (CCMs). In view of this presentation, we sequenced a bioinformatic panel of genes associated with susceptibility to meningioma, identifying a germline heterozygous variant inSMARCE1. Somatic DNA investigations in the CCM demonstrated the deletion of the wild-type allele (loss of heterozygosity, LOH), supporting the causative role of this variant. Family segregation study detected the SMARCE1 variant in the asymptomatic father and in the asymptomatic sister who, nevertheless, presents 2 spinal lesions. Germline heterozygous loss-of-function (LoF) variants in SMARCE1, encoding a protein of the chromatin-remodeling complex SWI/SNF, have been described in few familial cases of susceptibility to meningioma, in particular the CCM subtype. Our case confirms the role of NGS in investigating predisposing genes for meningiomas (multiple or recurrent), with specific regard to SMARCE1 in case of pediatric CCM. In addition to the age of onset, the presence of familial clustering or the coexistence of multiple synchronous meningiomas also supports the role of a genetic predisposition that deserves a molecular assessment. Additionally, given the incomplete penetrance, it is of great importance to follow a specific screening or follow-up program for symptomatic and asymptomatic carriers of pathogenic variants in SMARCE1.

De Novo Skull Base Atypical Meningioma: Incidence and Outcome

Objective  Atypical meningiomas are uncommon in skull base practice and present a management challenge. We aimed to review all de novo atypical skull base meningioma cases within a single unit to analyze presentation and outcome. Methods  A retrospective review of all patients undergoing surgery for intracranial meningioma identified consecutive cases of de novo atypical skull base meningioma. Electronic case records were analyzed for patient demographics, tumor location and size, extent of resection, and outcome. Tumor grading is based on the 2016 WHO criteria. Results  Eighteen patients with de novo atypical skull base meningiomas were identified. The most common tumor location was the sphenoid wing in 10 patients (56%). Gross total resection (GTR) was achieved in 13 patients (72%) and subtotal resection (STR) in 5 patients (28%). There was no tumor recurrence recorded in patients who had undergone GTR. Patients with tumors >6 cm were more likely to undergo a STR as opposed to a GTR ( p  < 0.01). Patients who had undergone a STR were more likely to have postoperative tumor progression and be referred for radiotherapy ( p  = 0.02 and <0.01, respectively). On multiple regression analysis, tumor size is the only significant factor correlating with overall survival ( p  = 0.048). Conclusion  The incidence of de novo atypical skull base meningioma is higher in our series than currently published data. Tumor size was a significant indicator for patient outcome and extent of resection. Those undergoing a STR were more likely to have tumor recurrence. Multicenter studies of skull base meningiomas with associated molecular genetics are needed to guide management.

Advances in Boron Neutron Capture Therapy (BNCT) for Recurrent Intracranial Meningioma

Meningiomas are the most frequently diagnosed primary intracranial tumors in adults. Surgical resection is preferred if the meningioma is accessible; for those that are not suitable for surgical resection, radiotherapy should be considered to improve local tumor control. However, recurrent meningiomas are challenging to treat, as the recurrent tumor might be located in the previously irradiated area. Boron Neutron Capture Therapy (BNCT) is a highly selective radiotherapy modality in which the cytotoxic effect focuses mainly on cells with increased uptake of boron-containing drugs. In this article, we describe four patients with recurrent meningiomas treated with BNCT in Taiwan. The mean boron-containing drug tumor-to-normal tissue uptake ratio was 4.125, and the tumor mean dose was 29.414 GyE, received via BNCT. The treatment response showed two stable diseases, one partial response, and one complete response. We also introduce and support the effectiveness and safety of BNCT as an alternative salvage treatment for recurrent meningiomas.

A Case of Giant Cutaneous Lopez Type III Meningioma of the Scalp

Meningiomas are the most common central nervous system (CNS) tumors. Extracranial meningiomas are rare, constituting 2% of all meningiomas. We describe a case of Lopez type III meningioma of the scalp in a 72-year-old gentleman who had a long-standing giant scalp mass and presented with recent mild left-sided limb weakness and numbness. Magnetic resonance imaging (MRI) of the skull demonstrated a right frontoparietal tumor extending through the skull into the scalp. Tumor excision revealed World Health Organization (WHO) grade 1 meningioma. Clinicians should correlate a cutaneous skull mass and new onset of neurological symptoms. Cutaneous meningioma is an important differential diagnosis.

Clinical Management of Supratentorial Non-Skull Base Meningiomas

Supratentorial non-skull base meningiomas are the most common primary central nervous system tumor subtype. An understanding of their pathophysiology, imaging characteristics, and clinical management options will prove of substantial value to the multi-disciplinary team which may be involved in their care. Extensive review of the broad literature on the topic is conducted. Narrowing the scope to meningiomas located in the supratentorial non-skull base anatomic location highlights nuances specific to this tumor subtype. Advances in our understanding of the natural history of the disease and how findings from both molecular pathology and neuroimaging have impacted our understanding are discussed. Clinical management and the rationale underlying specific approaches including observation, surgery, radiation, and investigational systemic therapies is covered in detail. Future directions for probable advances in the near and intermediate term are reviewed.

High-resolution cortical parcellation based on conserved brain landmarks for localization of multimodal data to the nearest centimeter

Precise cortical brain localization presents an important challenge in the literature. Brain atlases provide data-guided parcellation based on functional and structural brain metrics, and each atlas has its own unique benefits for localization. We offer a parcellation guided by intracranial electroencephalography, a technique which has historically provided pioneering advances in our understanding of brain structure-function relationships. We used a consensus boundary mapping approach combining anatomical designations in Duvernoy's Atlas of the Human Brain, a widely recognized textbook of human brain anatomy, with the anatomy of the MNI152 template and the magnetic resonance imaging scans of an epilepsy surgery cohort. The Yale Brain Atlas consists of 690 one-square centimeter parcels based around conserved anatomical features and each with a unique identifier to communicate anatomically unambiguous localization. We report on the methodology we used to create the Atlas along with the findings of a neuroimaging study assessing the accuracy and clinical usefulness of cortical localization using the Atlas. We also share our vision for the Atlas as a tool in the clinical and research neurosciences, where it may facilitate precise localization of data on the cortex, accurate description of anatomical locations, and modern data science approaches using standardized brain regions.

Development and Growth of Intracranial Meningiomas in Transgender Women Taking Cyproterone Acetate as Gender-Affirming Progestogen Therapy: A Systematic Review

Background

Gender-affirming hormone therapy is critical to the management of transgender persons. Cyproterone acetate (CPA) is a synthetic, progesterone-like compound commonly used in high doses as gender-affirming progestogen therapy in transgender women. An association between high-dose CPA and the development and growth of intracranial meningioma, including case reports in transgender women, has been described. This systematic review summarizes these cases at the patient level and discusses their management.

Methods

This systematic review was registered with PROSPERO (CRD42020191965). A detailed search of the PubMed, EMBASE, and Web of Science electronic bibliographic databases was performed (inception-December 20, 2020). Two review authors independently completed screening, data extraction, and risk of bias assessment in duplicate.

Results

Nine records were included describing (n=12) individual case reports and (n=35) intracranial meningiomas. The median age at presentation was 48 years (interquartile range [IQR], 43-55 years), most frequent daily CPA doses were 50 mg/day (n=5) and 100 mg/day (n=5), and the median duration of CPA use was 9.5 years (IQR, 6.5-17.5 years). Multiple meningiomas were common (n=7). For most cases (n=10), surgical resection was the initial preferred management strategy, but two were successfully managed by CPA cessation.

Conclusions

Transgender women receiving high doses of CPA may be at increased risk of intracranial meningioma development and/or growth, although this remains a rare disease. For presumed CPA-associated meningioma, drug cessation appears to be an appropriate management strategy when surgery is not imminently required to manage raised intracranial pressure or prevent neurological deterioration. Given the importance of gender-affirming hormone therapy to transgender persons, a suitable alternative hormone regimen should be offered, although the use of CPA in both high doses and for prolonged periods of time is now in decline.

Radiographic Differentiation of Secretory Meningiomas and WHO Grade 2 Meningiomas: When Atypical Features Are Not Always Predictive of Atypical Tumors

OBJECTIVE

Secretory meningioma (SM) is a rare subtype of World Health Organization (WHO) grade 1 meningioma, associated with significant peritumoral brain edema (PTBE). Because of this, SM may be mistaken preoperatively to be a WHO grade 2 meningioma (G2M). In this study, we identified radiographic features to differentiate these 2 tumor types preoperatively to help inform surgical decision-making.

METHODS

We performed a retrospective review of all patients with histologically confirmed intracranial SM and G2M at a single institution from 2000 to 2019. Relevant clinic, demographic and radiographic data were collected. We performed a stepwise multivariable logistic regression to identify independent predictors of SM.

RESULTS

A total of 43 SM and 140 G2M patients were included in this study. In multivariable analysis, severe PTBE, meaning edema size greater than tumor size (odds ratio [OR] 4.44, P = 0.01), tumor hyperintensity on fluid-attenuated inversion recovery (FLAIR) magnetic resonance imaging sequences (OR 7.80, P = 0.002), and higher normalized apparent diffusion coefficient (nADC) values (OR 1.54, P < 0.001) were strong predictors of SM. Conversely, larger tumor volume (OR 1.79 per 10 mL volume increase, P < 0.001) and cystic component (OR 12.50, P = 0.007) correlated with G2M.

CONCLUSIONS

In this study, we found that preoperative FLAIR hyperintensity, severe PTBE, and higher nADC values correlated with SM pathology, and larger size and cystic component were associated with G2M. Accurate identification of SM on preoperative imaging may provide surgeons useful information in decision-making.

Molecular determinants of outcomes in meningiomas

Meningiomas are the most common intracranial primary tumor in adults. Surgery is the predominant therapeutic modality for symptomatic meningiomas. Although the majority of meningiomas are benign, there exists a subset of meningiomas that are clinically aggressive. Recent advances in genetics and epigenetics have uncovered molecular alterations that drive tumor meningioma biology with prognostic and therapeutic implications. In this review, we will discuss the advances on molecular determinants of therapeutic response in meningiomas to date and discuss findings of targeted therapies in meningiomas.

Development of an Image-Based Methodology for the Evaluation of Histopathological Features in Human Meningioma

Meningioma is the most common intracranial tumor in adulthood. With a clear female predominance and a recurrence rate that reaches 20%, it is, despite being considered a benign tumor, a pathology that greatly compromises post-diagnosis quality of life. Its prone to recur or progress to a higher degree is difficult to predict in the absence of obvious histological criteria. This project aims to develop an automatic methodology to aid in the diagnosis of meningiomas that is objective and easily reproducible. The methodology is based on histopathological image analysis using artificial intelligence and machine learning algorithms. It includes a semi-automatic process of identification and cleaning of the scanned samples, an automatic detection of the nuclei of each image and, finally, the parameterization of the samples. The obtained data together with the clinical information will be analyzed using statistical methods in order to provide a methodology to support clinical diagnosis and decision-making in patient management. The result is the development of an effective methodology that generates a set of data associated with morphological parameters with different trends according to the pathological groups studied. A tool has been developed that allows an effective semiautomatic analysis of the images to evaluate these parameters in an objective and reproducible way, helping in clinical decision-making and facilitating to undertake projects with large sample series. Clinical Relevance- The main contribution of this project is in the field of neuropathology, for the diagnosis of meningiomas, the most common brain tumor. The present project provides an objective and quantifiable prognosis methodology for the meningiomas, offering a more precise monitoring of the treatment applied to the patient, resulting in a better prognosis and better quality of life.

Midline Skull Base Meningiomas: Transcranial and Endonasal Perspectives

Simple Summary

Skull base meningiomas have always represented a challenge for neurosurgeons. Despite their histological nature, they may be associated with unfavorable outcomes due to their deep-seated location and the surrounding neurovascular structures. Over time, several corridors have been proposed, each one carrying its own pros and cons. During the last decades, the endoscopic endonasal route has been asserted among the classic routes for a growing number of midline and paramedian lesions. Therefore, the aim of our paper is to present a comprehensive review of the indications and techniques for the management of skull base meningiomas, emphasizing the ambivalent and complementary role of the low and high routes.

Abstract

Skull base meningiomas have always represented a challenge for neurosurgeons. Despite their histological nature, they may be associated with unfavorable outcomes due to their deep-seated location and the surrounding neurovascular structures. The state of the art of skull base meningiomas accounts for both transcranial, or high, and endonasal, or low, routes. A comprehensive review of the pertinent literature was performed to address the surgical strategies and outcomes of skull base meningioma patients treated through a transcranial approach, an endoscopic endonasal approach (EEA), or both. Three databases (PubMed, Ovid Medline, and Ovid Embase) have been searched. The review of the literature provided 328 papers reporting the surgical, oncological, and clinical results of different approaches for the treatment of skull base meningiomas. The most suitable surgical corridors for olfactory groove, tuberculum sellae, clival and petroclival and cavernous sinus meningiomas have been analyzed. The EEA was proven to be associated with a lower extent of resection rates and better clinical outcomes compared with transcranial corridors, offering the possibility of achieving the so-called maximal safe resection.

Numerical analysis of the optical fluence rate at the scalp for noninvasive brain tumor detection

The present study provides a noninvasive, safe approach for brain tumor detection by numerically analyzing the optical fluence rate at the scalp. The proposed numerical investigation demonstrates the application of different laser wavelengths for identifying different types and volumes of brain tumors (glioma "grade II astrocytoma" and meningioma). The proposed method analyzes the spatial fluence rate distribution over the surface of the head after probing it with different infrared laser wavelengths (1000 and 1100 nm) to distinguish between normal and brain tumors. A multilayer head model is created with COMSOL Multiphysics 5.4 simulation software, where the Helmholtz equation is solved using a finite element method to visualize the optical fluence rate at the model's surface. The resultant fluence rate images show different features between normal brain and brain tumors, especially at 1000 nm.

YouTube as a Source of Patient Information for Meningiomas: A Content Quality and Audience Engagement Analysis

YouTube (YT) has become a popular health information reservoir. In this study, we aimed to evaluate the content and quality of YT videos as a source of patient information for meningiomas. A YT search was conducted for the following terms: “meningioma”, “meningiomas”, “meningeal tumor”, and “psammoma”. A total of 119 videos were examined by five independent raters, using validated quality criteria, including the Quality Criteria for Consumer Health Information (DISCERN), the Journal of the American Medical Association instrument (JAMA), and the Global Quality Score (GQS). The mean DISCERN score was 35.6 points, while the mean GQS and JAMA scores were 2.4 and 1.8, respectively. The majority of the videos were produced in the United States (37.82%). Moreover, 47.9% of the evaluated videos were graded as “poor” and only 9.24% were “good”. Statistically higher scores in all three scoring systems were associated with the following information: tumor localization, clinical manifestations, indications for surgery, treatment options, risks, adjuvant therapies, results, follow up, diagrams, and those that featured a doctor as the speaker. Misleading information was presented in 35 productions. Our findings show that the overall quality of YT on the topic of meningiomas is defective, and requires further improvement and evaluation.

A systematic review and meta-analysis of the association between cyproterone acetate and intracranial meningiomas

The influence of exposure to hormonal treatments, particularly cyproterone acetate (CPA), has been posited to contribute to the growth of meningiomas. Given the widespread use of CPA, this systematic review and meta-analysis attempted to assess real-world evidence of the association between CPA and the occurrence of intracranial meningiomas. Systematic searches of Ovid MEDLINE, Embase and Cochrane Controlled Register of Controlled Trials, were performed from database inception to 18th December 2021. Four retrospective observational studies reporting 8,132,348 patients were included in the meta-analysis. There was a total of 165,988 subjects with usage of CPA. The age of patients at meningioma diagnosis was generally above 45 years in all studies. The dosage of CPA taken by the exposed group (n = 165,988) was specified in three of the four included studies. All studies that analyzed high versus low dose CPA found a significant association between high dose CPA usage and increased risk of meningioma. When high and low dose patients were grouped together, there was no statistically significant increase in risk of meningioma associated with use of CPA (RR = 3.78 [95% CI 0.31–46.39], p = 0.190). Usage of CPA is associated with increased risk of meningioma at high doses but not when low doses are also included. Routine screening and meningioma surveillance by brain MRI offered to patients prescribed with CPA is likely a reasonable clinical consideration if given at high doses for long periods of time. Our findings highlight the need for further research on this topic.

Retrospective Analysis and Comparison of 48 Intracranial Meningioma Cases As Two Groups According to Their Size

Objective

This study aims to examine the possible demographic, clinical, and surgical differences between giant and smaller meningiomas.

Materials and Methods

Forty-eight meningioma patients who were operated on in our clinic between 2016-2020 were included in our study. Fourteen meningiomas larger than 5 cm in diameter were defined as giant meningiomas and placed in group 1. Thirty-four remaining meningiomas, with sizes less than 5 cm, were placed in group 2. These patients were evaluated regarding age, sex, localization, symptoms and neurological findings, surgical results, histopathology, and postoperative results.

Results

The most common localization in group 1 was falcine-parasagittal, whereas in group 2 it was convexity. Simpson’s grade I resection rate in group 1 was 35.71%, while in group 2 this rate was 67.65%. In histopathological examination, transitional type meningiomas (35.71%) were the most common in group 1, whereas fibrous type meningiomas (32.35%) were seen the most in group 2. Group 1 Karnofsky Performance Scale score average was 75.71 preoperatively and 85.71 postoperatively. In group 2, the preoperative and postoperative average was 97.35 and 96.76, respectively. The comparative statistical analysis reflects that: A) Resection rates were significantly lower in the giant meningioma group. B) Similarly, Karnofsky Performance Scale scores were also lower than group 2. C) When statistical comparisons were made according to sex, age, localization, histopathological results, postoperative complications, and recurrence rates, no significant differences were observed.

Conclusion

The term “Giant Meningioma” is a type of distinction that is frequently made in the literature. However, the single major difference we see in our study was the surgical results. The general condition of patients before and after surgery may be more critical than others in giant meningiomas. Although surgical resection is the main form of treatment in giant meningiomas, the risks arising from the size of the tumor should be taken into account, and necessary plans should be made for a successful surgical intervention.

Consensus core clinical data elements for meningiomas

BACKGROUND

With increasing molecular analyses of meningiomas, there is a need to harmonize language used to capture clinical data across centers to ensure that molecular alterations are appropriately linked to clinical variables of interest. Here the International Consortium on Meningiomas presents a set of core and supplemental meningioma-specific Common Data Elements (CDEs) to facilitate comparative and pooled analyses.

METHODS

The generation of CDEs followed the four-phase process similar to other National Institute of Neurological Disorders and Stroke (NINDS) CDE projects: discovery, internal validation, external validation, and distribution.

RESULTS

The CDEs were organized into patient- and tumor-level modules. In total, 17 core CDEs (10 patient-level and 7-tumour-level) as well as 14 supplemental CDEs (7 patient-level and 7 tumour-level) were defined and described. These CDEs are now made publicly available for dissemination and adoption.

CONCLUSIONS

CDEs provide a framework for discussion in the neuro-oncology community that will facilitate data sharing for collaborative research projects and aid in developing a common language for comparative and pooled analyses. The meningioma-specific CDEs presented here are intended to be dynamic parameters that evolve with time and The Consortium welcomes international feedback for further refinement and implementation of these CDEs.

Are there predilection sites for intracranial meningioma? A population-based atlas

Meningioma is the most common benign intracranial tumor and is believed to arise from arachnoid cap cells of arachnoid granulations. We sought to develop a population-based atlas from pre-treatment MRIs to explore the distribution of intracranial meningiomas and to explore risk factors for development of intracranial meningiomas in different locations. All adults (≥ 18 years old) diagnosed with intracranial meningiomas and referred to the department of neurosurgery from a defined catchment region between 2006 and 2015 were eligible for inclusion. Pre-treatment T1 contrast-enhanced MRI-weighted brain scans were used for semi-automated tumor segmentation to develop the meningioma atlas. Patient variables used in the statistical analyses included age, gender, tumor locations, WHO grade and tumor volume. A total of 602 patients with intracranial meningiomas were identified for the development of the brain tumor atlas from a wide and defined catchment region. The spatial distribution of meningioma within the brain is not uniform, and there were more tumors in the frontal region, especially parasagittally, along the anterior part of the falx, and on the skull base of the frontal and middle cranial fossa. More than 2/3 meningioma patients were females (p < 0.001) who also were more likely to have multiple meningiomas (p < 0.01), while men more often have supratentorial meningiomas (p < 0.01). Tumor location was not associated with age or WHO grade. The distribution of meningioma exhibits an anterior to posterior gradient in the brain. Distribution of meningiomas in the general population is not dependent on histopathological WHO grade, but may be gender-related.

Hypofractionated Stereotactic Radiotherapy for the Treatment of Benign Intracranial Meningiomas: Long-Term Safety and Efficacy

Introduction: Hypofractionated stereotactic radiotherapy (hSRT) has emerged as an alternative to single-fraction stereotactic radiosurgery (SRS) and conventionally fractionated radiotherapy for the treatment of intracranial meningiomas (ICMs). However, there is a need for data showing long-term efficacy and complication rates, particularly for larger tumors in sensitive locations. Methods: A retrospective review was conducted on adult patients with ICMs seen at a tertiary care center. Eligible patients were treated with the CyberKnife platform and had a planned treatment course of 3–5 fractions from 2011–2020. The local control was assessed based on radiographic stability and the late toxicity/radionecrosis rates were recorded. Radiographic progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan–Meier method. Results: In total, 62 patients (age 26–87) with 67 treated tumors were included in this study with a median follow-up of 64.7 months. RT was delivered as the primary treatment in 62.7% of cases and for recurrence in 37.3%. The most common tumor locations were the convexity of the brain and the base of the skull. The tumor sizes ranged from 0.1–51.8 cc and the median planning target volume was 4.9 cc. The most common treatment schedule was 18 Gy in 3 fractions. The five-year PFS and OS were 85.2% and 91.0%, respectively. The late grade III/IV toxicity rate was 3.2% and the radionecrosis rate was 4.8%. Conclusions: Based on our data, hSRT remains an effective modality to treat low-grade ICMs with acceptable long-term toxicity and radionecrosis rates. hSRT should be offered to patients who are not ideal candidates for SRS while preserving the benefits of hypofractionation.

Simple Ways to Estimate Meningioma Volume: Can ABC- and SH-Derived Methods Be Used in Clinical Practice Reliably?

Background

There is a clinical demand for rapid estimation of meningioma volumes. Our objective was to assess the accuracy of three ABC-derived and three SH-derived formula methods on volume estimation of meningiomas.

Methods

The study group comprised 678 patients treated at our department for histopathologically proven intracranial meningiomas. For each patient, tumor volumes were independently measured using six formula methods as well as planimetry. Maximum tumor diameter and ellipsoidity were also recorded. Volumes were compared using descriptive statistics, correlation analysis, and consistency analysis.

Results

Among all methods assessed, 2/3SH and 1/2ABC outperformed the others. No significant differences were found between volumes obtained by the two methods and those of planimetry (p > 0.05). Spearman rank-correlation coefficients (r _s ) were 0.99 for both methods (p < 0.01), and ICC were 0.99 and 0.98, respectively. In Bland-Altman plot, most data points lay inside the limit of agreement. Overall, 2/3SH overestimated tumor volumes by 1.29%, and estimation errors in 93.66% cases were within 20%; 1/2ABC overestimated tumor volumes by 5.36%, and estimation errors in 93.51% cases were within 30%. The performance of 2/3SH and 1/2ABC in small-volume meningiomas was slightly worse, especially for 1/2ABC. Correlations between ellipsoidity and percentage errors of 2/3SH and 1/2ABC were weak (r _s  = -0.06 and -0.24, respectively). Despite a significant correlation between maximum tumor diameter and planimetric volume (r _s  = -0.96), volumes could vary significantly for a given diameter.

Conclusions

Formula methods 2/3SH and 1/2ABC can estimate meningioma volumes with decent accuracy. Compared with the 1/2ABC method, the 2/3SH method showed slightly better performance, especially in small-volume meningiomas. Ellipsoidity is not a suitable parameter to predict estimation error, and maximum tumor diameter is not a reliable surrogate for actual meningioma volume.

Diagnostic nomogram model for predicting preoperative pathological grade of meningioma

Background

Meningioma is the most common primary tumor of the central nervous system. Preoperative diagnosis of high-grade meningioma is helpful for the selection of treatment options. The aim of our study is to establish a diagnostic nomogram model for preoperative prediction of the pathological grade of meningioma.

Methods

The predictive model was established from a cohort of 215 clinicopathologically confirmed meningioma between January 2012 and December 2017. Radiomic features were collected from preoperative magnetic resonance imaging (MRI) and computed tomography of patients with meningioma. The least absolute shrinkage and selection operator (LASSO) regression model was used for data dimension reduction and feature selection. Multivariate logistic regression was used to build a predictive model and presented as a nomogram. The performance of the nomogram was assessed with respect to its calibration, discrimination, and clinical usefulness. Internal validation was evaluated using bootstrapping validation.

Results

High-grade meningioma was observed in 47 patients (22%). The predictors included in the nomogram were tumor-brain interface, bone invasion, and tumor location. The final diagnostic model exhibited good calibration and discrimination with a C-index of 0.874 (95% confidence interval: 0.818–0.929) and a higher C-index of 0.868 in internal validation. Decision curve analysis (DCA) indicated that the nomogram is very useful in clinical practice.

Conclusions

This study provides a nomogram model with tumor-brain interface, bone invasion, and tumor location that can effectively predict the preoperative pathological grading of patients with meningioma and thus help clinicians provide more reasonable treatment strategies for meningioma patients.

Stereotactic Radiosurgery for Olfactory Groove Meningiomas: An International, Multicenter Study

BACKGROUND

Stereotactic radiosurgery (SRS) is increasingly considered for selected olfactory groove meningiomas (OGMs).

OBJECTIVE

To investigate the safety and efficacy of SRS for OGMs.

METHODS

From 20 institutions participating in the International Radiosurgery Research Foundation, we pooled patients who underwent SRS for histologically confirmed or radiologically suspected WHO grade I OGMs and were followed for 6 mo or more after the SRS.

RESULTS

In total, 278 (median age 57 yr) patients underwent SRS for histologically confirmed (29%) or radiologically suspected (71%) WHO grade I OGMs Median treatment volume was 4.60 cm3 (range: 0.12-27.3 cm3), median prescription dose was 12 Gy, and median dose to the olfactory nerve was 11.20 Gy. During median post-SRS imaging follow-up of 39 mo (range: 6-240 mo), 43% of patients had partial or marginal response, 54% of patients had stable disease, and 3% of patients experienced progression. During median post-SRS clinical follow-up of 51 mo (range: 6-240 mo), 36 (13%) patients experienced clinical and/or radiological adverse radiation events (AREs). Elevated risk of AREs was associated with larger OGM volume (P = .009) and pre-SRS peritumoral T2/fluid-attenuated inversion-recovery signal abnormalities (P < .001). After the SRS, olfaction remained stable, improved, or deteriorated in 90%, 8%, and 2% of patients, respectively. Complete post-SRS anosmia was predicted by partial/complete anosmia before the SRS (odds ratio [OR] = 83.125; 95% CI [24.589-281.01], P < .001) and prior resection of OGM (OR = 3.919; 95% CI [1.713-8.970], P = .001).

CONCLUSION

SRS is associated with durable local control of the majority of OGM patients with acceptable safety profile. SRS allows preservation or improvement of olfactory function in the majority of OGM patients.

Lateral Ventricular Meningiomas: Clinical Features, Radiological Findings and Long-Term Outcomes

Purpose

Lateral ventricle meningioma (LVM) is a rare type of intracranial meningioma, which has been rarely studied. It has different clinical features, imaging features, and long-term results from other locations. This study investigated the epidemiology, clinical characteristics and prognosis of LVM and comprehensively describes its characteristics.

Methods

This article analyzes the LVMs that were diagnosed pathologically in West China hospital between January 1, 2009 and July 1 2020. Demographic information, imaging characteristics and prognostic factors are discussed. Data analysis was performed using SPSS 23.0 and R version 3.5.3.

Results

We collected 7202 meningiomas and 195 LVMs (136 females; median age, 46 years; range, 5–81 years) were included in this study. Gross total resection was completed in 189 patients. The OS rate was 93.8%, and the recurrence rate was 5.2%. Multivariate regression analysis showed that sex (P = 0.01) and tumor size (P = 0.018) were related to WHO grade. Postoperative KPS (P = 0.003) was associated with OS. WHO grade (P = 0.025), extent of tumor resection (P < 0.001), and hospital day (P=0.028) were associated with recurrence.

Conclusion

LVMs require long-term follow-up, individualized treatment, and follow-up strategies to be formulated according to the relevant risk factors.

[Meningiomas: A review of current knowledge]

Meningiomas are the most frequent among intracranial tumors, and represent more than 30% of primitive central nervous system neoplasms. Arising from the meninges, they are generally benign lesions and can be treated by either radio-clinical follow-up or surgical resection with excellent outcome. However, more than 20% of meningiomas harbor atypical or malignant features and represent challenges for both prognostic evaluation and therapeutic strategy. The discovery of the genetic and epigenetic landscapes of meningiomas enabled the identification of new prognostic markers and potential therapeutic targets for refractory meningiomas. This review summarizes current epidemiology, histological and molecular characteristics, diagnosis and treatments for meningiomas, and highlights the close relationship between the development of meningiomas and hormonal intake, as illustrated by recent recommendations of the "Agence Nationale de Securité du Medicament", the French national drug safety agency.

Biomarkers for differentiating grade II meningiomas from grade I: a systematic review

INTRODUCTION

There are a number of prognostic markers (methylation, CDKN2A/B) described to be useful for the stratification of meningiomas. However, there are currently no clinically validated biomarkers for the preoperative prediction of meningioma grade, which is determined by the histological analysis of tissue obtained from surgery. Accurate preoperative biomarkers would inform the pre-surgical assessment of these tumours, their grade and prognosis and refine the decision-making process for treatment. This review is focused on the more controversial grade II tumours, where debate still surrounds the need for adjuvant therapy, repeat surgery and frequency of follow up.

METHODS

We evaluated current literature for potential grade II meningioma clinical biomarkers, focusing on radiological, biochemical (blood assays) and immunohistochemical markers for diagnosis and prognosis, and how they can be used to differentiate them from grade I meningiomas using the post-2016 WHO classification. To do this, we conducted a PUBMED, SCOPUS, OVID SP, SciELO, and INFORMA search using the keywords; 'biomarker', 'diagnosis', 'atypical', 'meningioma', 'prognosis', 'grade I', 'grade 1', 'grade II' and 'grade 2'.

RESULTS

We identified 1779 papers, 20 of which were eligible for systematic review according to the defined inclusion and exclusion criteria. From the review, we identified radiological characteristics (irregular tumour shape, tumour growth rate faster than 3cm³/year, high peri-tumoural blood flow), blood markers (low serum TIMP1/2, high serum HER2, high plasma Fibulin-2) and histological markers (low H3K27me3, low SMARCE1, low AKAP12, high ARIDB4) that may aid in differentiating grade II from grade I meningiomas.

CONCLUSION

Being able to predict meningioma grade at presentation using the radiological and blood markers described may influence management as the likely grade II tumours will be followed up or treated more aggressively, while the histological markers may prognosticate progression or post-treatment recurrence. This to an extent offers a more personalised treatment approach for patients.

Quality of YouTube Videos on Meningioma Treatment Using the DISCERN Instrument

OBJECTIVE

To assess the quality of YouTube videos on meningioma treatment.

METHODS

A search was performed on YouTube using the keywords "meningioma treatment," "meningeal tumor treatment," "meningioma brain tumor treatment," "meningioma cure," and "meningioma therapy." Sixty-one videos were independently evaluated by 2 fifth-year medical students using the DISCERN scoring system for quality analysis. Quantitative data such as video length, source of upload, and popularity and their associations with DISCERN scores were also evaluated.

RESULTS

The mean total DISCERN score was 36.4. Approximately a third of YouTube videos were classified as very poor, 32.8% as poor, 11.5% as fair, 16.4% as good, and 4.9% as excellent. The question "Does the video refer to areas of uncertainty?" obtained the lowest score (2.0), and the question "Does the video describe how each treatment works?" obtained the highest score (3.0). Videos authored by a health information channel had the highest mean total DISCERN score (46.7, standard deviation = 14.6). Videos had significantly higher DISCERN scores if they included information about the symptoms of meningioma, risk factors during treatment, prognosis, or included animations and diagrams. DISCERN scores were moderately positively correlated with duration of videos and referrers and moderately negatively correlated with number of channel subscribers, video power index, and average daily views.

CONCLUSION

The information content on meningioma treatment in YouTube videos was generally poor. The impact of inaccurate YouTube videos on patients' understanding of meningioma treatment must be recognized by health care professionals.

Tumor volume and the dural tail sign enable the differentiation of intracranial solitary fibrous tumor/hemangiopericytoma from high-grade meningioma

OBJECTIVES

Intracranial solitary fibrous tumor/hemangiopericytoma (SFT/HPC) is a rare mesenchymal neoplasm with imaging features mimicking high-grade meningioma (HGM) and can easily be misdiagnosed. We sought to determine the value of routine preoperative data in differentiating these tumors.

PATIENTS AND METHODS

Patients with confirmed SFT/HPC or HGM between January 2012 and June 2020 were identified. A total of 28 preoperative variables (including age, sex, tumor location, tumor volume, 10 traditional MRI features, and 14 peripheral blood indices) were collected for each patient. The top features were selected sequentially based on the least absolute shrinkage and selection operator (LASSO) and support vector machines-recursive feature elimination (SVM-RFE) methods. Differentiation and calibration of the classifiers were assessed by receiver operating characteristic (ROC) curves and calibration curves, respectively. Nomograms were constructed based on multivariate analysis.

RESULTS

A total of 127 patients, including 29 with SFT/HPC and 98 with HGM, were analyzed. Three features were first selected using the LASSO and SVM-RFE methods, and corresponding models were developed. Although the area under the curve (AUC) of model 1 was the highest, a comprehensive analysis suggested the superiority of model 2, which consisted only of the features tumor volume (TV) and dural tail sign (DTS) (AUC: 0.942, sensitivity: 93.10%, p-value of H-L test: 0.734, Brier score: 0.07). A risk score formula and a nomogram were constructed.

CONCLUSIONS

TV can be used to effectively identify SFT/HPC and HGM, whereas adding DTS can improve the overall prediction accuracy. As these two variables are routinely available and are easy for clinicians to master, they can provide a powerful reference for clinical decision-making.

Meningiomas: A review of general, histopathological, clinical and molecular characteristics

OBJECTIVES

In this review, the main histological and molecular characteristics of meningiomas will be addressed, as well as the aspects most related to clinical conditions, treatment, and survival of patients, enabling a better understanding of these tumors behavior.

METHODS

This study was conducted with the search for published studies available on NCBI, PubMed, MEDLINE, Scielo and Google Scholar. Relevant documents have been identified and 50 articles were selected.

RESULTS

The main points about meningiomas were characterized, as well as the histological presence of spontaneous necrosis in grade I and brain invasion as diagnostic criteria, their molecular origin related to deletion of chromosome 22 and mutations in theNF2 and TERT genes, in addition to their clinical characteristics. The preferential treatment remains the total resection of the tumor.

CONCLUSION

The information about meningiomas is well known and necessary, but it is expected that more work will emerge related to the behavior of these tumors, and that the scientific community will obtain more clarity about the best ways to conduct the patients treatment.

Risk Factors for High-Grade Meningioma in Brain and Spine: Systematic Review and Meta-analysis

BACKGROUND

Histologic grade has important implications for the management in meningioma. It is important to understand the risk of high-grade meningioma (grades II and III). In this article, we systematically reviewed the histologic grade of meningioma depending on the location and sex and its relationship with recurrence.

METHODS

The PubMed and Embase databases were systematically searched until February 4, 2020. We included studies that were not restricted to specific anatomic locations, histologic grade, or the sizes of the tumors. The proportion of high-grade meningiomas depending on the location and sex and the odds ratio (OR) of recurrence were pooled using a random-effects model.

RESULTS

Outcome data were analyzed for 20,336 tumors from 34 studies. We found different proportions of high-grade meningiomas in the brain (12.8%) (95% confidence interval [CI], 10.5%-15.1%) versus the spine (2.4%) (95% CI, 1.0%-3.7%) (P < 0.01). Skull base meningiomas (8.7%) (95% CI, 5.8%-11.6%) had a lower proportion of high-grade meningiomas than non-skull base meningiomas (16.5%) (95% CI, 11.9%-21.1%) (P < 0.01). In addition, high-grade meningiomas were more likely to occur in male patients (18.0%) (95% CI, 10.1%-25.9%) than female patients (7.0%) (95% CI, 3.5%-10.6%) (P = 0.01). Higher rates of recurrence (OR = 13.83) were confirmed for high-grade meningiomas than grade I meningiomas (95% CI, 4.10-46.65) (P < 0.01).

CONCLUSIONS

This meta-analysis found that intracranial, nonskull base, and male sex are risk factors for high-grade meningioma, and high-grade meningioma had a much higher recurrence rate as compared with grade I 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.