Primary malignant peripheral nerve sheath tumor of the spine with acute hydrocephalus: a rare clinical entity.

Primary malignant peripheral nerve sheath tumors (MPNSTs) are extremely rare in patients without a history of neurofibromatosis; only 18 cases have been reported in the English-language literature to this point. The authors report their experience with 1 new case of a primary MPNST. A 33-year-old woman presented with low-back pain radiating to the right calf that progressed over 1 year. Magnetic resonance imaging of the spine revealed an intradural extramedullary lesion at the T12-L1 level. The patient was diagnosed with primary MPNST, underwent two surgical excisions and radiation therapy, and developed leptomeningeal metastases as well as brain metastases. The patient revisited the emergency room with sudden loss of consciousness. A brain CT scan displayed bilateral lateral ventricle enlargement, for which a ventriculoperitoneal shunt was inserted. These symptoms have not been described in any previous report. Primary spinal MPNST is an exceedingly rare entity, and the overall prognosis is very poor. To the authors' knowledge, no standard of care for primary spinal MPNSTs has yet been established. All 19 cases of primary spinal MPNSTs are reviewed, and the authors discuss their clinical, radiological, and therapeutic features and outcomes.