Tumefactive and longitudinally extensive myelitis: A rare presentation of multiple sclerosis?

Cerebral tumefactive demyelinating lesions are well described in multiple sclerosis (MS). Yet few cases of MS-associated tumefactive spinal cord demyelination have been described. We report a patient with a clinical course typical of relapsing-remitting MS who presented with a relapse associated with a tumefactive and longitudinally extensive cervical spinal cord lesion. Despite extensive evaluation, and with two years of longitudinal follow up, no better explanation than MS could be identified. This case highlights the diagnostic and prognostic challenges associated with presumed tumefactive spinal cord demyelination in MS, and the unmet need for further cases to guide therapeutic decision-making.