Spinal Nerve Sheath Myxoma

Abstract

Nerve sheath myxoma (NSM) is a rare myxoid form of schwannoma, which is a benign tumor that usually grows in the same place. They usually arise from small cutaneous nerves in the head, neck, and extremities, but exceptionally, they have also been reported to develop in the spinal canal. Here we describe a case of spinal NSM. The patient was a 4-month-old male who presented with incomplete tetra paresis. Spine magnetic resonance imaging showed a well-demarcated small intradural extramedullary mass at the T10-L1 level. The tumor has typical histological features of myxoid type NSM with myxoid lobules that are separated by fibrous septa or bands of more compact cellular area. Nerve sheath myxomas should be included in the differential diagnosis of spinal canal tumors. Ultrastructural observation of tumor cefis with perineurial, fibroblast-like, and Schwann differentiation suggests an origin from nerve sheath precursor cefis.