Diagnostic and therapeutic strategy for confounding radiation myelitis.

We report a case of confounding radiation myelitis to demonstrate the usefulness of surgical biopsy in ensuring the correct diagnosis and to avoid unnecessary treatment. The patient was a 40-year-old man with a history of epiglottis carcinoma and sarcoidosis. Six months after radiation therapy and chemotherapy for epiglottis carcinoma, he noticed paresthesia and dysesthesia in the left arm and leg. Two months after that, he complained of severe neck pain and rapidly progressing weakness in all extremities. MRI showed an enhanced intramedullary lesion with extensive edema in the cervical spinal cord. Radiation myelitis, intramedullary spinal tumor, and neurosarcoidosis were considered as differential diagnoses. Spinal cord biopsy with laminectomy was performed and radiation myelitis was diagnosed. After the surgery, the lesion was significantly decreased in size even though corticosteroid therapy was rapidly tapered. We emphasize that a spinal cord biopsy is indicated to obtain a pathological diagnosis and to make a clear treatment strategy for patients with associated diseases causing lesions of the spinal cord.