Correlations between surface marker patterns in meningiomas, prognosis and location.

Background: Meningiomas exhibit considerable phenotypic variation within each WHO grade, thus additional markers are needed to identify prognostically relevant subgroups and optimize long-term management. Among biomarkers, genetic signatures correlate with prognoses. High Ki-67 proliferation indices and TERT promotor mutations and loss of CDKNA are known prognostic markers.

The concept, intention, and evaluation of the term treatment-refractory meningioma.

Background: Treatment-refractory meningioma is a widely used term but lacks standardized criteria, impairing research comparability and treatment evaluation. The aim of this study was to assess the heterogeneity of patient populations labeled as treatment-refractory and to explore recommendations for better consistency.

Methods: We systematically reviewed 69 studies published before 2024 and analyzed individual participant data from 15 cohorts (n = 211) that included treatment-refractory patients who underwent experimental therapy with somatostatin receptor (SSTR)-targeted therapies.

Diabetes is associated with a decreased risk of meningiomas: a mendelian randomization study.

Background: Meningiomas are the commonest primary intracranial tumors, but the risk factors are complex and not fully understood. Type 1 and 2 diabetes mellitus (T1DM and T2DM) are frequently occurring endocrine diseases, but their relationship with meningiomas is debated. Obesity and elevated body mass index (BMI) are known risk factors for meningiomas but often confound with diabetes.

Sinonasal DLBCL: molecular profiling identifies subtypes with distinctive prognosis and targetable genetic features.

Primary sinonasal diffuse large B-cell lymphoma (PSDLBCL) is a rare lymphoma with a variable prognosis and a unique relapse/dissemination pattern involving the central nervous system and skin. The underlying molecular mechanisms leading to this heterogeneity and progression pattern remain uncharted, hampering patient-tailored treatment. To investigate associated mechanisms, we analyzed clinical data and used immunohistochemistry, gene-expression profiling, cytogenetics, and next-generation sequencing in a cohort of 117 patients with PSDLBCL.

Translocator protein (TSPO) expression in neoplastic cells and tumor-associated macrophages in meningiomas.

Meningiomas are the most common primary intracranial tumors and show extensive infiltration of macrophages. The mitochondrial membrane protein translocator protein (TSPO) has been used as an in vivo marker of microglia and macrophage activation to visualize neuroinflammation. However, it is unknown which cell types express TSPO in meningiomas.

The experience of living with malignant meningioma.

Objectives: Meningiomas are the most common, primary intracranial tumor and most are benign. Little is known of the rare patient group living with a malignant meningioma, comprising 1-3% of all meningiomas. Our aim was to explore how patients perceived quality of daily life after a malignant meningioma diagnosis.

DNA methylation profile of human dura and leptomeninges.

Healthy meninges are used as control tissue in meningioma studies usually without specification of the exact meningeal layer or macroanatomical origin but the DNA methylation profile of human meninges has not been investigated on a macroanatomical level. We undertook a proof-of-principle analysis to determine whether (1) meningeal tissues show sufficiently homogenous DNA methylation profiles to function as normal control tissue without further specification and (2) if previously described location-specific molecular signatures of meningiomas correspond to region-specific DNA methylation patterns. Dura mater and arachnoid membrane specimens were dissected from 5 anatomical locations in 2 fresh human cadavers and analyzed with the Illumina Infinium MethylationEPIC array.

Gene expression analysis during progression of malignant meningioma compared to benign meningioma.

Objective: Meningioma is the most common primary intracranial neoplasm. Only 1%-3% of meningiomas are malignant according to the 2016 WHO criteria (WHO grade III). High-grade meningiomas present specific gene expression signatures indicating aggressive growth or recurrence.

Somatostatin analogues in treatment-refractory meningioma: a systematic review with meta-analysis of individual patient data.

Treatment-refractory meningiomas have a dismal prognosis and limited treatment options. Meningiomas express high-densities of somatostatin receptors (SSTR), thus potentially susceptible to antitumorigenic effects of somatostatin analogues (SSA). Evidence for SSA in meningiomas is scarce, and it is unclear if published literature would either (1) support wider use of SSA, if (2) more evidence is desirable, or if (3) available evidence is sufficient to discard SSA.

Loss of H3K27me3 in WHO grade 3 meningioma.

Immunohistochemical quantification of H3K27me3 was reported to distinguish meningioma patients with an unfavorable prognosis but is not yet established as a prognostic biomarker within WHO grade 3 meningiomas. We studied H3K27me3 loss in a series of biopsies from primary and secondary malignant meningioma to validate its prognostic performance and describe if loss of H3K27me3 occurs during malignant transformation. Two observers quantified H3K27me3 status as "complete loss", < 50% and > 50% stained cells in 110 tumor samples from a population-based consecutive cohort of 40 WHO grade 3 meningioma patients.

Adjuvant radiotherapy and stereotactic radiosurgery in grade 3 meningiomas - a systematic review and meta-analysis.

Malignant meningioma is a rare, aggressive form of meningioma. Radiation is commonly included in treatment guidelines either as adjuvant radiotherapy (RT) or stereotactic radiosurgery (SRS). Nevertheless, the treatment recommendations are not supported by prospective comparative trials and systematical, critical evaluation of supportive evidence is lacking.

Granular clinical history and outcome in 51 patients with primary and secondary malignant meningioma.

Objective: WHO grade III meningiomas, also known as malignant meningiomas (MMs), are rare, and the heterogenous clinical course in patients with MM is not well described. To characterize the clinical course of patients with MM, granular clinical data were gathered from 51 patients treated at the Department of Neurosurgery and Radiation Oncology, Rigshospitalet, in Copenhagen, Denmark, between 2000 and 2020.

Methods: The authors investigated outcome and timing in terms of 1) tumor progression and grade transformation in patients previously diagnosed with WHO grade I or II meningiomas (patients with a secondary MM [sMM]); 2) performance status and complications following surgery; and 3) transition to noncurative treatment and ultimately death.

Implementation of TERT promoter mutations improve prognostication of the WHO classification in meningioma.

TERT promoter mutations have been associated with increased risk of recurrence in meningioma cohorts, thus a potential biomarker for aggressive phenotypes. A main purpose of refining tumour classification is better predictions on the patient level. We compiled data from previous published cohorts to investigate patient-level predictions of recurrence based on TERTp-mut status.

Proposal of a new grading system for meningioma resection: the Copenhagen Protocol.

Introduction: The extent of meningioma resection is the most fundamental risk factor for recurrence, and exact knowledge of extent of resection is necessary for prognostication and for planning of adjuvant treatment. Currently used classifications are the EANO-grading and the Simpson grading. The former comprises radiological imaging with contrast-enhanced MRI and differentiation between "gross total removal" and "subtotal removal," while the latter comprises a five-tiered differentiation of the surgeon's impression of the extent of resection.

Meningioma-Brain Crosstalk: A Scoping Review.

: In recent years, it has become evident that the tumoral microenvironment (TME) plays a key role in the pathogenesis of various cancers. In meningiomas, however, the TME is poorly understood, and it is unknown if glia cells contribute to meningioma growth and behaviour. : This scoping review investigates if the literature describes and substantiates tumour-brain crosstalk in meningiomas and summarises the current evidence regarding the role of the brain parenchyma in the pathogenesis of meningiomas.

Pathologic Characteristics of Pregnancy-Related Meningiomas.

Meningiomas are the most common intracranial tumor. During pregnancy, explosive growth of a known meningioma occasionally occurs, but the underlying reasons remain unknown. Prolactin has been suggested as a possible key contributor to pregnancy-related meningioma growth.

Expression of the stem cell marker CD133 in malignant meningioma.

The stem cell marker CD133 has been sporadically investigated in meningioma, but because of the rarity of malignant meningioma (WHO grade III), only 7 malignant meningioma specimens have been included in previous studies. We investigated CD133 expression using the AC133 antibody clone in a consecutive cohort of 38 malignant meningiomas. Our results showed few, small CD133-positive hot spots with a pattern dominated by membranous staining and capping of the proteins without any nuclear CD133 staining in 30 of the 38 tumors.

TERT promoter mutations in primary and secondary WHO grade III meningioma.

Purpose: TERT promoter mutation (TERTp ) has a strong association to recurrence and has been suggested to act as a driver mutation for malignant transformation of WHO grade I and II meningiomas. TERTp has been investigated in selected high-grade meningioma samples. The existence of TERTp across recurrent tumors in a population-based cohort needs to be investigated in order to identify when TERTp emerges across recurrent samples and to validate prognostic impact among WHO grade III tumors.

Poor prognosis associated with TERT gene alterations in meningioma is independent of the WHO classification: an individual patient data meta-analysis.

Background: gene alterations (-alt) have been linked to increased risk of recurrence in meningiomas, whereas the association to mortality largely remain incompletely investigated. As incongruence between clinical course and WHO grade exists, reliable biomarkers have been sought.

Methods: We applied the Preferred Reporting Items for Systematic Review and Meta-Analyses of individual participant data Statement.

Clinical and histopathological predictors of outcome in malignant meningioma.

We investigated possible clinical and histopathological prognostic factors in a malignant meningioma cohort with comprehensive long-term population-based follow-up data. Twenty-four consecutive patients treated surgically for malignant meningioma at the Department of Neurosurgery and the Department of Pathology, Rigshospitalet, Copenhagen, Denmark, from December 2000 to March 2014 were retrospectively evaluated regarding progression-free survival (PFS) and overall survival (OS). Clinical parameters were recorded.