Malignant schwannoma: report of a case mimicking lumbar disk disease.

Primary neurogenic retroperitoneal tumors in the adult are rare. This case presentation reviews an unusual history of a patient who presented with pain and neurologic deficits suggesting lumbar disk disease but who was unrelieved by laminectomy and disk removal. Later he was found to have a malignant schwannoma arising from the right L nerve root. Experience such as this reminds physicians that when the result of treatment is not as expected the original diagnosis must be questioned.