Solitary Fibrous Tumor of the Spinal Nerve Rootlet Report of a Case Mimicking Schwannoma

Figure 1. A preoperative sagittal magnetic resonance image with gad-olinium of the lumbar region shows an irregularly enhancing mass at the L1-L2 level. c We report a case of solitary fibrous tumor involving the spinal nerve root at the L1-L2 level in a 67-year-old man. The patient presented with lumbar pain and weakness in his right lower extremity. Histologically, the tumor was composed of a proliferation of monomorphous spindle cells in an abundant collagenous stroma; neither necrosis nor mitoses were evident. These cells were strongly im-munoreactive with CD34, Bcl-2, CD99, and vimentin, but were negative with S100 protein, smooth muscle actin, and epithelial membrane antigen. Such an immunohistochem-ical profile was consistent with a solitary fibrous tumor of the spinal nerve rootlet and ruled out the main differentia