Endodermal cyst of the cervical spinal cord with associated partial fusion of the vertebrae.

A case of a 43-year-old woman with an intradural endodermal cyst at the C4 spinal cord level is presented. The lesion manifested with progressive neck pain and weakness of lower extremities. The presumptive diagnosis of extramedullary benign cystic lesion was established after MRI examination. Coexisting partial fusion of the C5-C6 vertebral bodies was found on X-ray films. The patient was cured by resection of the cyst wall, performed by laminectomy. Pathological examination revealed a cyst wall lined with ciliated cuboidal cells, resembling the respiratory epithelium. Immunohistochemistry demonstrated cytokeratin and epithelial membrane antigen expression in the lining of the cyst. Endodermal cyst should be considered in the differential diagnosis of intraspinal cystic lesions, especially those associated with vertebral anomalies.