LHERMITTE-DUCLOS DISEASE (DYSPLASTIC GANGLIOCYTOMA)

WHO Grade I

Cell of Origin: Cerebellar neurons (hamartomatous?)

Synonyms: Ganglioneuroma, Purkinjioma, Granular cell hypertrophy of the cerebellum, Gangliocytoma dysplasticum, Hamartoma of the cerebellum

Common Locations: Cerebellar hemispheres

Demographics: Early adulthood

Clinical Presentation: Hydrocephalus; may also be found as an incidental lesion

Histology: Derangement of normal laminar cellular organization of cerebellum: 1) Thickening of outer molecular cell layer, 2) Loss of middle Purkinje cell layer, 3) Infiltration of inner granular cell layer with dysplastic ganglion cells

Special Stains: Synaptophysin positive

Progression: Good prognosis with surgical excision. Recurrence rare.

Radiology: Non-enhancing cerebellar hemisphere mass with characteristic striated MR appearance. Occasionally contains calcifications.

Comments: Association with Cowden's disease (mucosal neuromas and breast cancer)