Intravascular lymphoma of the central nervous system: a rare subtype of a common disease

A 67-year-old man had a sudden onset of headache and aphasia, evolving to spontaneous improvement. A few months later, he developed dysarthria and left hemiparesis. Brain MRI showed several punctate lesions with perilesional edema, perivascular enhancement and restricted diffusion on DWI. PET-CT demonstrated mild uptake. Anatomopathological and immunohistochemical analysis were compatible with intravascular large B-cell lymphoma (IVL). Treatment with R-CHOP and intrathecal methotrexate was established, with favorable response due to high tumor sensitivity. Approximately half of IVL cases are diagnosed only after autopsy. The main differential diagnoses are vasculitis, neurosarcoidosis, and ischemic stroke.