Meningeal tumors of infancy and childhood.

Seventeen meningeal tumors were examined for pathology with electron microscopy and immunohistochemistry including glial fibrillary acidic protein (GFAP), S-100 protein, muramidase, and factor VIII. These tumors included seven meningiomas, one hemangiopericytoma, three meningeal sarcomas (1 pleomorphic-cell type and 2 myxofibrosarcomas), two fibrous histiocytomas, and four malignant melanomas. Two of seven children with meningioma had a poor outcome despite the benign histological features of the tumor. S-100 protein was present in the two tumors. All three children with meningeal sarcoma had a rapid downhill clinical course, although the myxofibrosarcoma initially had a relatively benign histological appearance. The two children with fibrous histiocytoma did well despite the aggressive histological features. Muramidase was a good marker of such tumors. Because of the morphological difficulties associated with childhood meningeal tumors, both electron microscopy and immunohistochemistry can be of diagnostic benefit.