Intravascular lymphoma mimicking multiple sclerosis

Diagnosis of relapsing–remitting multiple sclerosis requires demonstration disseminated symptoms in time and space on the basis of neurological assessment or magnetic resonance imaging findings. In addition, the diagnosis is conditioned by ruling out other conditions that may explain the clinical symptoms.We describe the patient presenting in the initial stage of the disease neurological symptoms and magnetic resonance imaging lesions, that met criteria for relapsing–remitting multiple sclerosis diagnosis.The patient was administered immunomodulatory treatment. However, the subsequent course of the disease tended to verify the diagnosis. Finally, the patient was diagnosed with intravascular B-cell lymphoma.Intravascular lymphoma is a rare form of lymphoma characterized by the development of cancerous cells in the lumen of small and medium-sized blood vessels.Due to the lack of characteristic biomarkers in laboratory tests and neuroimaging, the diagnosis is based on histopathological examination of the sample of the affected organ taken by biopsy. It should be consider in all cases of central nervous system damage of unknown, undiagnosed etiology.