Case 096

History/Physical

History/Physical:

33-year-old right-handed female.

Mild gait ataxia over the past year.

Mild left dysmetria.

Small T2-hyperintense intra-axial lesion in the inferior left cerebellum (*).

The lesion has low signal on T1 (*). Mass effect is minimal.

Diagnosis: Pleomorphic xanthoastrocytoma

Lymphocytic infiltrates (*) and tumour cells displaying xanthomatous (vacuolated) cytoplasm (arrow).

Pleomorphic cells, fibrillary background and scattered eosinophilic granular bodies (arrow).

Marked pleomorphism (*) in cells of ambiguous lineage (neuronal vs. glial).

Reticulin stains reveal basement membrane around individual tumour cells (*).