《Slide 165.》Meningioma, Meninges

A. Brief Descriptions：

1. Arising from the meningothelial cell of the arachnoid.

2. Histologic pattern: syncytial, fibroblastic, transitional, psammomatous, angiomatous, etc.

B. Gross Findings：

1. Encapsulated，round masses with a well-defined dura base and easily seperated.

2. Firm to fibrous and lack of hemorrhage and necrosis.

3. Hyperostotic reaction in the overlying bone.

C. Micro Findings：

1. Sheets and whorls of polygonal cells, with large, pale spheroid, central nuclei and abundant cytoplasm supported by collagen stroma.

2. Psammoma bodies can also be found.

D. Others:

1. Meningioma起源於subarachnoid的meningothelial cells，所以在腦的表面和腦室內，甚至沿著spinal cord都可以發生meningioma。常見於parasagittal aspect of the convexity，dura over the lateral convexity，the wing of the sphenoid，olfactory groove，sella turcica，foramen magnum.

2. Slow growing and expressing progesterone receptors.

3. 在染色體第22對上的long arm缺失。

4. 特殊染色: EMA positive and CEA positive.

E. Reference：

1. Robbins Pathologic Basis of Disease, 6^th ed.  P.1350-1351.

　

 

 

【 Fig. 165-1 (LP)】The tumor in section is whorled and lobulated.

 

 

【 Fig. 165-2 (LP)】

　

　

  

【 Fig. 165-3 (LP)】Meningotheliomatous cells with polygonal to spindle shape and whorl appearance, and sycytoplasmic cells in the center of whorl.

　

 

【 Fig. 165-4 (LP)】Mineralized psammoma body.