BCL6 and infarction: MRI brain: hemorrhagic infarct in left frontal lobe with focal bilateral parietal lobe infarct; EEG: potential epileptogenic activity in left frontal region; MRI/CT head after 2 weeks: new infarcts, mass effect in right ventricles and MLS to left; brain biopsy: diffuse proliferation of malignant lymphocytes within the lumina of both large and small vessels with luminal obstruction; immunophenotyping: +CD20, -CD5, +BCL-2, +MUM-1, -CD10, -BCL-6