Page 639 - Concise Pathology for Exam Preparation ( PDFDrive )

624 SECTION II Diseases of Organ Systems

Whorls of
meningothelial
cells

Psammoma
body

FIGURE 23.2. Section from a meningioma shows polygonal cells with ill-defined cytoplasmic
margins arranged in sheets and tight groups with presence of whorling and psammoma bodies
(H&E; 2003).

3.
Presence of small cells
Prominent nucleoli
4.
5.
Necrosis
r
o
Features indicating/suggesting malignant change (Anaplastic grade III/IV meningioma):

• Infiltration of underlying brain by a tumour with the appearance of a high-grade sarcoma

with some diagnostic features of a meningioma.

• Abundant mitoses (.20 mitoses/10 HPF)
• Multifocal microscopic foci of necrosis

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