Angiotropic lymphoma (malignant angioendotheliomatosis) presenting with rapidly progressive dementia.

An 87-year-old male presented with rapidly progressive dementia, disorder of consciousness and myoclonus, suggesting Creutzfeldt-Jakob disease, but with nonspecific EEG and negative CT findings. Autopsy revealed a malignant angiotropic lymphoma with accumulation of tumor cells within small vessels of the brain and visceral organs. Immunohistochemistry disclosed a large cell lymphoma of B cell type.