Chordoid meningioma of the foramen magnum in a child: a case report and review of the literature.

We report a 3-year-6-month-old boy with chordoid meningioma in the foramen magnum. Chordoid meningioma represents between 0.5 and 1.0% of all meningiomas, and it is frequently located in the supratentorial region. The patient started with an episode of instability, falls, and headache; after which, he developed cuadriparesis, cervical pain, and neck stiffness, which slightly improved after medical treatment, so he was referred to our hospital. Physical examination revealed left hemiparesis and cervical muscle spasm with left torticollis. Magnetic resonance imaging (MRI) demonstrated an intradural-extramedullary well-circumscribed, homogeneous enhancing mass, in the anterior part of the foramen magnum with cervical extension. The operative technique was the extreme-lateral craniocervical retrocondylar approach with total removal and dural coagulation. Histopathological examination demonstrated a chordoid meningioma, with meningotelial basophilic mucoid chordoma-like component in 80% of the tissue. The immunohistochemical stains were positive to epithelial membrane antigen, vimentin, and S-100 protein. At 10 months follow-up, the patient showed improvement in his neurological deficit with physical rehabilitation, and motor response in his extremities are now normal; neck stiffness with cervical spasm disappeared postoperatively. MRI showed no residual tumor. To our knowledge, this is the first report of a chordoid meningioma on the foramen magnum in a child.