Meningioma

CNS tumor

Meningeal tumors

Meningioma

Authors: Jesse L. Kresak, M.D., Anthony T. Yachnis, M.D.

Topic Completed: 1 December 2014

Minor changes: 12 December 2019

Copyright: 2002-2019, PathologyOutlines.com, Inc.

PubMed Search: Meningioma [title] CNS

Page views in 2019: 57,095

Page views in 2020 to date: 37,814

Table of Contents

Cite this page: Kresak JL, Yachnis AT. Meningioma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/cnstumormeningiomageneral.html. Accessed August 12th, 2020.

Definition / general

Most common primary brain tumor (20 - 30% of brain tumors, 6 per 100K annually)
Derive from arachnoid cap cells (associated with dura mater, choroid plexus)
Grow along external surface of brain or within ventricular system
Slow growing (may grow rapidly during pregnancy), symptoms vague or related to brain compression
Usually adults
Female predominance: 2/3 of cerebral meningiomas occur in women, 90% of spinal cord meningiomas occur in women
Usually solitary; multiple tumors (seen in 1 - 6%) are occasionally associated with neurofibromatosis 2
Three grades exist based on WHO criteria
- Most are WHO grade I (benign)
- ~6% are WHO grade II (increased likelihood of recurrence)
- Rarely are WHO grade III (malignant with metastatic potential)
Many variants of meningiomas exist
Grade I variants
- Angiomatous:
  - 2% of all meningiomas
  - Vascular component should exceed 50% of total tumor area
  - Meningothelial cells are wrapped around small blood vessels
  - Also has large vessels
  - Mean Ki67 index is 2%
  - Do not recur if entirely resected (Am J Surg Pathol 2004;28:390)
  - Differential diagnosis includes hemangioblastoma, which stains positive with inhibin and NSE
- Fibroblastic:
  - Firm tumors composed of spindle cells with indistinct cell boundaries
  - Sheet-like architecture, may not contain lobules or classic meningothelial whorls
  - Resemble schwannoma or solitary fibrous tumor but are focally EMA+, often have thick bundles of collagen
- Lymphocyte rich
  - May be associated with Castleman disease or other hematopoietic neoplasm
- Meningothelial:
  - Most common variant
  - Syncytial and epithelial cells, indistinct cell borders and classic whorls
  - May have sparse psammoma bodies
- Metaplastic:
  - May contain foci of bone, cartilage or fat
- Microcystic:
  - Rare to have extensive microcystic formation
  - Cells have elongated processes and loose myxoid background
  - Overall resembles microcysts
  - Has focal "classic" features
  - Variable pleomorphism
  - No cords or trabeculae, no inflammatory infiltrate
  - EM shows extracellular microcysts
- Psammomatous:
  - Found in spinal region
  - Numerous psammoma bodies
- Secretory:
  - Eosinophilic secretions
  - May have cytologic atypia
  - May secrete CEA
- Transitional:
  - Meningothelial and fibroblastic features
  - Usually prominent whorls, psammoma bodies and clusters of syncytial cells
Grade II variants
Grade III variants

Radiology description

Strong and homogenous enhancement on MRI with contrast
Usually display a "dural tail"
Usually isodense with the gray matter on T1 weighted MRI
May show a so called "CSF crest" around the tumor indicating its extra-axial location

Case reports

11 year old boy with pediatric microcystic meningioma (Childs Nerv Syst 2013;29:361)
22 year old man with microcystic meningioma, WHO grade I (Case of the Week #104)
37 year old woman with dural based intracranial masses (Arch Pathol Lab Med 2005;129:e173)
61 year old man with left brain mass (Case of the Week #373)
Angiomatous meningioma of orbit mimicking as malignant neoplasm (Orbit 2011;30:183)
Breast carcinoma metastatic to meningioma (J Clin Neurosci 2015;22:268)
Dumbbell meningioma of the upper cervical spinal cord (J Orthop Sci 2013;18:1042)
Leukemic infiltrate within a meningioma (Am J Surg Pathol 2001;25:127)

Treatment

Observation - if asymptomatic
Gross total resection is usually curative
Postoperative radiation if incompletely excised or WHO grade II or III

Gross description

Rounded and well circumscribed
Attached to dura
Tumor separates readily from brain
May grow en plaque (along dural surface) and cause reactive (hyperostotic) bone changes

Gross images

Images hosted on other servers:

Tumor displaces brain without invading

Compression of underlying cortex

Resected tumor

Adherent to falx cerebri

Microscopic (histologic) description

Arachnoid plane exists between meningioma and CNS parenchyma
Lobulated architecture, often contain "meningothelial" whorls
Syncytial cells with indistinct cell membranes
Eosinophilic cytoplasm
Round uniform nuclei, intranuclear pseudoinclusions common
May contain psammoma bodies
Xanthomatous degeneration, moderate nuclear pleomorphism and metaplasia may be seen but have no prognostic significance
Rarely necrosis or extensive hemorrhage

Microscopic (histologic) images

Scroll to see all images:

Case of the Week #373 (angiomatous)

Smears:

Additional smears:

Frozen section:

H&E images:

Additional H&E images:

Immunostains were obtained:

CD34

EMA

MUC1

Ki67

S100

BCL2

p63

PASD

Contributed by Fisnik Kurshumliu, M.D., Ph.D.

Calcified and hyalinized blood vessels

Images hosted on other servers:

Angiomatous (trichrome stains)

Fibroblastic variant

Lipomatous variant

Lymphoplasmacytic rich variant is CD45+

Meningothelial variant

Meningothelial - intraosseous hyperostotic occipital

Meningothelial variant

Microcystic variant:

Lace-like pattern of fibrillary stellate cells

Pleomorphic cells

Pseudo-astrocytic appearance

ProgR+ and EMA+

Psammomatous

Xanthomatous variant

Xanthomatous with cholesterol clefts and pleomorphic cells

Cytology description

Small to medium sized cells with moderate well defined cytoplasm and short processes
Some nuclei have grooves
Cells form focal whorls
Variable psammoma bodies

Cytology images

Case of the Week #104