Intramedullary amputation neuromas associated with spinal ependymomas

A large intramedullary neurofibroma in the thoracic spinal cord: case report

Neurofibromas are occasionally present in spinal roots; however, an intramedullary neurofibroma is especially rare. Although a few cases of intramedullary neurofibromas in cervical spinal cord have been reported, to the best of our knowledge, there are no reports of intramedullary neurofibromas in thoracic spinal cord, and moreover, no reports have clearly reported immunohistochemical findings. We report a rare case of a large intramedullary neurofibroma in the thoracic spinal cord and show immunohistochemical examination of the tumor. A 52-year-old man presented with a 2-year history of progressive gait disturbance. Neurological examinations demonstrated complete motor and sensory deficit of his legs. Magnetic resonance imaging of the thoracic spine demonstrated an intramedullary enhancing mass within the spinal cord between T4 and T5 levels. The patient underwent T3–T6 laminectomy surgery. The dura mater was opened to reveal fusiform dilatation of the spinal cord and a midline myelotomy was performed. An intramedullary mass was revealed and could be resected totally. Histopathological examination revealed that the tumor cells exhibited spindle-shaped and wavy nuclei with abundant collagen, which resembled schwannoma or fibrous meningioma. By immunohistochemical examination, some tumor cells were positive for S-100 proteins; however, most tumor cells were strongly positive for CD34. From these pathological findings and immunohistochemical reactions, we diagnosed the intramedullary tumor as a neurofibroma.

Intraoperative and pathological findings of intramedullary amputation neuroma associated with spinal ependymoma

Amputation neuromas typically arise in injured peripheral nerves; rarely, however, they arise in the spinal cord. We report a rare case of intramedullary amputation neuroma associated with ependymoma in the cervical spinal cord. A 73-year-old woman presented with a 5-year history of progressive gait disturbance. Neurological examination revealed complete motor deficit of her hands and legs. Magnetic resonance imaging of the cervical spine revealed an enhancing mass within the spinal cord at the C6/7 level. The patient underwent C5–C7 laminectomy surgery. During resection of the spinal tumor, we found a whitish string resembling an aberrant nerve root or schwannoma with adhesion to the tumor on the ventral side of the spinal cord. After resecting the tumor, the surgical specimen was cut and separated into a soft greyish tumor (spinal tumor) and the tough whitish string. Histopathological and immunohistochemical examination revealed the former was a spinal ependymoma and the latter was a neuroma. An intramedullary amputation neuroma associated with a spinal ependymoma is rare, and this is the first known case in which intraoprerative findings were clearly shown. Neurosurgeons should be aware that spinal ependymomas might coexist with neuromas.