Meningioma: Diagnosis and Classification

A 62-year-old female presents with a slowly progressing neurological deficit. Imaging reveals an extra-axial mass attached to the dura mater. Histopathological analysis indicates a WHO Grade I meningioma. Considering the molecular pathogenesis of meningiomas, which chromosomal alteration is most likely to be the primary driver in this patient's tumor, assuming it is located at the cerebral convexity?

In the context of meningioma grading according to the 2021 WHO classification of CNS tumors, which of the following histological features, if present in a meningioma, would necessitate upgrading it from WHO Grade I to at least Grade II, irrespective of the specific morphological variant?

A researcher is investigating the diagnostic utility of immunohistochemical markers in differentiating between various spindle cell neoplasms of the CNS. Which of the following marker combinations would most definitively distinguish a fibrous meningioma from a solitary fibrous tumor (SFT) / hemangiopericytoma?

Consider a patient diagnosed with a secretory meningioma. Genetic analysis reveals a mutation profile characterized by combined KLF4 and TRAF7 mutations. Based on current understanding of meningioma pathogenesis, which of the following statements most accurately reflects the expected clinical behavior and location of this tumor?

A 45-year-old patient with a history of childhood radiation therapy for leukemia presents with a newly diagnosed meningioma. Considering the etiology of meningiomas, which molecular mechanism is most likely to be implicated in the tumorigenesis in this specific clinical context?

In the differential diagnosis of a spinal mass lesion, a psammomatous meningioma is considered. Which of the following immunohistochemical profiles would be most consistent with a psammomatous meningioma and help differentiate it from other spinal tumors?

Loss of H3K27 trimethylation (H3K27me3) has been identified as a prognostic marker in meningiomas. In which grades of meningioma has the loss of H3K27me3 by immunohistochemistry been shown to predict a poorer prognosis, and what is the proposed mechanism?

DNA methylation profiling is increasingly recognized as a superior prognostic tool in meningiomas compared to WHO histological grading alone. According to the methylation-based classification, which methylation class (MC) is associated with the most aggressive clinical behavior and poorest prognosis?

In the context of angiomatous meningiomas, which of the following statements regarding their genetic characteristics and differential diagnosis is most accurate?

A pathologist is examining a cytology crush preparation of a brain tumor. The smear shows epithelioid cells with round to oval nuclei, streaked cytoplasm, and cellular whorls. Which of the following cytological features is considered most pathognomonic for a meningioma in such preparations?

A patient presents with a meningioma located in the cerebellopontine angle. While fibrous meningioma is in the differential, schwannoma is also highly considered. Which of the following immunohistochemical markers would be most useful to definitively differentiate between these two entities in this location?

Microcystic meningiomas are known for their unique histological and immunohistochemical profile. Which of the following features is characteristically associated with microcystic meningiomas and distinguishes them from other meningioma variants?

In the management of meningiomas, observation is sometimes considered a viable option. Under which of the following clinical scenarios would observation be most appropriate as the primary management strategy for a newly diagnosed meningioma?

The gross description of a meningioma often includes its relationship to the dura and surrounding brain tissue. Which of the following macroscopic features is most characteristic of a meningioma's interaction with the brain parenchyma?

Clear cell meningiomas, a WHO Grade II variant, are genetically distinct and often present diagnostic challenges. Which of the following molecular alterations is most strongly associated with the pathogenesis of clear cell meningiomas?

Lymphoplasmacyte-rich meningiomas are a rare variant, representing less than 1% of all meningiomas. What is a notable clinical or pathological association that has been observed in some cases of lymphoplasmacyte-rich meningiomas?

Considering the ectopic presentation of meningiomas, which anatomical region is identified as the most common site for ectopic meningiomas outside of the central nervous system?

Dumbbell meningiomas represent a specific growth pattern, particularly in the spinal region. What anatomical characteristic defines a dumbbell meningioma in the spinal cord?

TERT promoter mutation has been investigated in the context of meningioma progression and grading. In which specific scenario is TERT promoter mutation most likely to be detected in meningiomas, according to current research?

In the differential diagnosis of chordoid meningioma, chordoma and chordoid glioma are considered. Which immunohistochemical marker is most critical in distinguishing chordoid meningioma from chordoma?

When comparing meningothelial meningioma with meningothelial hyperplasia, what is the most significant histological feature that distinguishes meningioma from hyperplasia?

Which of the following statements accurately describes the gender predilection in meningioma incidence across different anatomical locations within the CNS?

In the context of meningioma prognosis, recurrent losses of specific chromosomes have been identified as indicators of poor outcome. Which of the following sets of chromosomal losses is associated with a worse prognosis in meningiomas?

Which of the following WHO Grade 1 meningioma variants is most likely to be genetically characterized by combined KLF4 and TRAF7 mutations?

Extensive peritumoral edema is typically associated with brain invasion in meningiomas. However, certain WHO Grade I variants can also exhibit prominent peritumoral edema. Which of the following sets of Grade I variants are known to potentially present with significant peritumoral edema?

In the context of molecular classification of meningiomas, NF2 mutated meningiomas are predominantly associated with which morphological subtypes and anatomical locations?

Pediatric meningiomas are distinct from adult meningiomas in several aspects, including their genetic profile and association with underlying conditions. Which of the following statements most accurately reflects the characteristics of pediatric meningiomas?

The upcoming 2021 WHO CNS tumor classification update emphasizes a critical principle in grading meningiomas. What is this key principle regarding the application of grading criteria for atypical and anaplastic meningiomas?

In distinguishing between angiomatous and microcystic meningiomas from hemangioblastomas, which immunohistochemical marker is most valuable in favoring a diagnosis of hemangioblastoma?

For which of the following meningioma variants is the differential diagnosis of vascular malformations most pertinent, particularly in radiological and microscopic assessment?

Which of the following WHO Grade 1 meningioma variants is characterized by eosinophilic round secretions, often termed pseudopsammoma bodies, that are positive for CEA and PAS stains?

In the genetic landscape of meningiomas, non-NF2 meningiomas are enriched in mutations in several genes. Which of the following sets of genes is most characteristically mutated in non-NF2 meningiomas, particularly those located in the skull base?

What is the primary rationale for considering postoperative radiation therapy in the management of meningiomas after surgical resection?

Which of the following is NOT considered an 'atypical feature' in the context of grading meningiomas according to WHO criteria, specifically in distinguishing between Grade 1 and Grade 2 meningiomas?

In the context of intracranial myxoid neoplasms, which immunohistochemical marker profile is most consistent with a chordoid glioma?

Which of the following molecular alterations is characteristic of nearly 100% of secretory meningiomas and is mutually exclusive to NF2 mutations?

What is the typical mitotic index threshold used to differentiate between WHO Grade 1 and Grade 2 meningiomas, as per the WHO criteria?