Solitary Fibrous Tumor of The Lumbar Spine: Case Report and Review of The Literature

Solitary fibrous tumor (SFT) is an uncommon spindle-cell neoplasm that typically arises in the pleural cavity. The lesion located in the spinal region is very uncommon. SFT resembles other spindle cell neoplasms of the spine and may be an unrecognized entity if not routinely considered in the differential diagnosis of spinal neoplasms. The authors report an unusual extradural location of lumbar SFT. A 63-year-old male presented with a six-month history of progressive weakness and numbness on the left lower extremity. On examination, weakness (Grade 4/5) of all muscle groups was demonstrated in the left lower extremity. Magnetic resonance imaging(MRI) of the lumbar spine revealed a 1.2-cm well-circumscribed extradural mass at lumbar-4. A lumbar 3–5 laminectomy was performed. The tumor was adherent to the nerve root and located in the left aspects of the spinal cord. Gross-total resection was attained. No residual or recurrent tumor was found on 30-month follow-up MRI. Findings in this case and a comprehensive review of the literature indicate that although SFTs of the spine are rare, they can originate from various spinal anatomical substrates. Immunohistochemistry should be used to differentiate SFT from other spinal spindle cell neoplasms. Although spinal SFTs have generally been described as slow growing, indolent, and nonaggressive tumors, they may recur even disseminate after a long period. Radical surgical excision seems to be a reliable prognosis factor. Some microscopic features probably also influence progression-free survival but must be further defined. SFT should be considered in the differential diagnosis of spinal lesions.