There is a proliferation of cells with clear cytoplasm with no particular organization. This is due to glycogen accumulation, which can be emphasized with a PAS stain. This variant is usually not mixed with other types, but in some cases, there will be areas of more conventional meningioma architecture such as syncytial or fibrous pattern (Prayson).
There is a haphazard arrangement of cells with clear glycogenated cytoplasm. Bundles of collagen are dispersed between the tumor cells.
Previously referred to as the "glycogen-rich" type, clear cell meningiomas (along with atypical meningioma and chordoid variants) tend to exhibit more aggressive behavior compared to most meningioma variants.
This variant usually arises in slightly different locations such as cerebellopontine angle and cauda equina. It is more commonly seen in younger patients (Fletcher, Prayson).
More likely to recur than the conventional type and thus, is categorized as a WHO Grade II tumor.
Fletcher CDM, ed. Diagnostic Histopathology of Tumors. 3rd Ed. Philadelphia, PA: Elsevier; 2007: 1708-9.
Prayson R, Kleinschmidt-Demasters BK, Cohen ML. Brain Tumors. Consultant Pathology Series New York, NY: Demos Publishing: 2010: 195-7.