Primary Intradural Extramedullary Melanoma of the Cervical Spinal Cord

Abstract

Case report. We report a case of primary intradural extramedullary melanoma of the cervical spinal cord in a nonwhite patient. Melanoma occurs most commonly in white populations and is rare in Asian populations. Primary malignant melanoma of the spinal cord is a rare disease entity that predominately affects the middle or lower thoracic spine. A 39-year-old man presented with a tingling sensation in the upper extremities accompanied by motor weakness of the lower extremities. Preoperative magnetic resonance imaging (MRI) of the cervical spine suggested a multiloculated subdural hematoma in the subacute stage that spread from the level of C1 to the level of C6. A standard posterior midline approach was used under the impression that the subacute subdural hematoma was caused by a hidden vascular anomaly or a rare, intradural, pigmented tumor. A dark black-colored, hard, intradural mass was found, and gross total removal was performed. Histopathological investigation confirmed malignant melanoma. No hypermetabolic lesions were noted on whole-body FDG-PET. Additional dermatologic and ophthalmologic examinations did not reveal any other foci of primary melanoma. The patient was discharged with improvement of motor weakness. Subsequent radiotherapy and chemotherapy were administered. Unlike most cases of primary intradural melanoma, this patient presented with unusual radiologic findings in the cervical spinal cord. The case described in the present study illustrates that primary spinal cord melanoma is rare and must be diagnosed with caution due to its variable clinical and radiologic presentation.