Intradural extramedullary xanthoma of the spine: a rare lesion arising from the dura mater of the spine: case report.

OBJECTIVE AND IMPORTANCE: Xanthomatous tumors of the central nervous system are occasionally found in several unrelated diseases such as Hand-Schüller-Christian disease, Weber-Christian disease, histiocytosis X, malignant fibrous histiocytoma, and a complication of metabolic or storage diseases. However, a solitary xanthoma without systemic disease is rare. We present an unusual case of a solitary and benign xanthoma arising in the spinal leptomeninges without systemic diseases or metabolic abnormality, including a lipid profile.

CLINICAL PRESENTATION: A 16-month-old male patient was admitted with a complaint of spastic paraparesis. His magnetic resonance images revealed an intradural extramedullary tumor that showed isosignal intensity on T1-weighted images and high signal intensity on T2-weighted images with homogenous gadolinium enhancement.

INTERVENTION: The tumor arising from the spinal meninges was totally removed. Histological findings and immunochemical studies positive for CD68 and lysozyme stain showed abundant histiocytic cells with foamy cytoplasm. Negative S-100 protein in the immunohistochemical study and the absence of Birbeck granules on an electromicroscopic study excluded the possibility of Langerhan's histiocytosis. These findings corresponded to xanthoma. The patient had no abnormality of lipid metabolism or familial history of xanthoma.

CONCLUSION: The patient improved enough to walk by himself 3 months after the operation.