Isolated large demyelinated plaque with clinical and radiologic appearance suggestive of cervical intramedullary tumor diagnosed after surgery

Isolated spinal demyelinating lesions are rare and often associated with multiple sclerosis. While initial radiological findings may suggest a tumor, a definitive diagnosis requires a histological diagnosis. A 45-year-old woman presented with progressive spastic tetraparesis for 1 week. She had no prior history of neurological or systemic illness. Brain and thoracic magnetic resonance imaging (MRI) were normal, but cervical MRI revealed an intramedullary tumor extending from C3 to C4. Surgery was performed. Histopathological examination revealed an inflammatory demyelinating plaque, not a tumor. The patient experienced significant improvement in her clinical condition postsurgery and remains under neurological follow-up. We discuss this case alongside a review of similar cases reported in the literature, focusing on clinical presentation, laboratory findings, MRI features, and follow-up of patients with tumor-like inflammatory demyelinating diseases of the spinal cord initially diagnosed as intramedullary tumors.