Solitary fibrous tumor of the thoracic spine. Case report and review of the literature.

Solitary fibrous tumor (SFT) is a neoplasm first described as a tumor of mesenchymal origin involving soft tissues. The authors provide a review of the literature with detailed pathological analysis and radiological description of SFTs involving the central nervous system. The authors report a rare case of a SFT of the thoracic spine in an adult man presenting with myelopathy. Magnetic resonance imaging revealed a well-circumscribed, intradural, extramedullary mass at the T2-3 level. Histological examination demonstrated a proliferation of predominantly spindle-shaped cells with a collagen-matrix background. Immunohistochemical staining was positive for vimentin and CD34 and negative for S-100 and epithelial membrane antigen with an MIB-1 labeling index of 2.6%. Review of the literature revealed 10 cases in which this tumor, frequently found in the pleura, was involved in the central nervous system. Although rare and their clinical significance as yet unknown, SFTs may be considered in the differential diagnosis of intradural spinal cord lesions. The natural history is also unknown, but these tumors appear to be biologically benign.