Fibrous meningioma

Fibrillary MXPE may be confused with fibrous meningioma and schwannoma. The epithelial and papillary variants may resemble carcinoma or meningioma. A positive GFAP stain response differentiates the MXPE from GFAP-negative carcinoma and meningioma. MXPE lacks type FV collagen and fibronectin-positive basement membranes around each cell, which is a feature of schwannoma (Fig. 20.24A). 

Fibrous meningiomas are firm tumors composed of spindle cells (see Table 20.5). They resemble schwannomas, solitary fibrous tumors, fibrillary astrocytomas, and pilocytic astrocytomas. Fibrous meningiomas contain parenchymal collagen, often in large, pink bundles on H E staining that distinguish them from astrocytomas. ... 

AC. The immunophenotypic spectrum of meningeal hemangiopericytoma A comparison with fibrous meningioma and solitary fibrous tumor of meninges. Am j Surg Pathol. 1997 21 1354-1360. 

The solitary fibrous tumor (SET) is a soft tissue tumor (see Chapter 4). It resembles fibrous meningioma but has a different immunohistochemical profile (see Figs. 

Carneiro SS, Scheithauer BW, Nascimento AG, et al. Solitary fibrous tumor of the meninges A lesion distinct from fibrous meningioma A clinicopathologic and immunohistochemical study. Am J Clin Pathol. 1996 106 217-224. 

Renshaw AA. 013 (CD99) in spindle cell tumors Reactivity with hemangiopericytoma, solitary fibrous tumor, synovial sarcoma, and meningioma, but rarely with sarcomatoid mesothelioma. Appl Immunohistochem. 1995 3 250-256. 

A cyst that is located in the posterior or lateral epidural space in the spinal canal and that is lined only by fibrous tissue resembling dura and lacking arachnoid membrane is a meningeal cyst or diverticulum (see Table 20.12). A subdural or subarachnoid cyst that has a thinner wall than the epidural cyst and that protrudes toward brain or spinal cord is an arachnoid cyst. Reactivity for vimen-tin, progesterone receptors, and EMA is common. This inununoreactivity resembles that of arachnoid granulations and meningiomas. Other cysts have variable thickness and are more difficult to categorize. 

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