central nervous system mesenchymal non-meningothelial tumor
A benign or malignant mesenchymal neoplasm originating in the central nervous system or the meninges and showing fibrous, fibrohistiocytic, adipose, myoid, endothelial, chondroid or osseous, but not meningothelial differentiation. Depending on the histological features and clinical behavior of these neoplasms, their grade ranges from benign (WHO grade I) to highly malignant (WHO grade IV). (Adapted from WHO)