Presentation
6 weeks of progressive ataxia, falls, 2 weeks of cognitive impairment.
Patient Data
Extensive deep white matter signal change demonstrated on both FLAIR and T2. The signal change extends to the subcortical region and also involves the splenium of the corpus callosum. The signal change appears more extensive posteriorly. No contrast enhancement of these areas or abnormal enhancement elsewhere. The posterior fossa appears uninvolved.
The time of flight and post contrast MRA (not shown) demonstrate normal anatomical variance with a foetal origin of the right PCA. There is no evidence of stenosis, or mural enhancement of the circle of Willis vasculature to suggest vasculitis.
CONCLUSION:
There is extensive bilateral white matter FLAIR signal change which is increased since the previous examination. The differential diagnosis includes demyelination (including ADEM) despite the patient's age. Other possibilities include vasculitis or intravascular lymphoma.
Case Discussion
The patient went on to have a brain biopsy (right frontal lobe)
Histology
MICROSCOPIC DESCRIPTION
The sections of cerebral white matter are mildly hypercellular, with focally prominent perivascular lymphocytic cuffing. There are diffusely increased astrocytes through the tissue, as well as a light scattering of macrophages and activation of microglial cells. The lymphocytes cuffing vessels are predominantly small CD3-positive T cells. Within some of these vessels are large atypical lymphoid cells with a high proliferative index on the Ki67 stain. Occasional single large atypical B-cells are present within perivascular parenchyma. The features are consistent with a diagnosis of intravascular large B cell lymphoma.
DIAGNOSIS
Right frontal white matter biopsies - large B-cell non-Hodgkin lymphoma, consistent with intravascular large B-cell lymphoma.