Intraosseous malignant peripheral nerve sheath tumor (MPNST) of the thoracic spine: a rare cause of spinal cord compression.

OBJECTIVE

To describe the management of a patient presenting with intraosseous MPNST of the thoracic spine causing cord compression.

SUMMARY OF BACKGROUND DATA: Malignant peripheral nerve sheath tumors (MPNST) are uncommon tumors of cells of peripheral nerve sheath origin. MPNST typically present as an enlarging mass originating from a peripheral nerve root in the trunk, extremities, and head and neck region. METHODS.: A 59-year-old woman presented with midthoracic back pain, paraparesis, and a T4 sensory level. Magnetic resonance image scan revealed a large enhancing and destructive lesion at the T3 level with cord compression.

RESULTS

Decompressive laminectomies, tumor debulking, and instrumentation was performed from a posterior approach. At surgery, the lesion was noted to originate from the T3 vertebral body, and separate from the dura and spinal nerve roots. Surgical excision was incomplete and the spine was stabilized with a Ti frame. MPNST was confirmed histologically. Despite adjuvant radiotherapy, she developed metastatic deposits in the spine and femur.

CONCLUSIONS

Intraosseous MPNST causing spinal cord compression has not been described as yet and should be added to the differential diagnosis of primary bone tumors causing cord compression. Prognosis with MPNST can be poor, especially in patients with large tumors, undergoing subtotal surgical resection and in association with neurofibromatosis.