[Dysplastic gangliocytoma of the cerebellum (Lhermitte-Duclos)].

In a surgical specimen from a 33-year old woman with features of expansive cerebellar symptomatology, dysplastic gangliocytoma of the cerebellum (Lhermitte-Duclos) was diagnosed by histology. The lesion was characterized by typical proliferation of dysplastic neuronal elements in the cortical granular and Purkinje cell layers. Immunohistology showed focal positivity of synaptophysin in some cells, thus confirming their neuronal origin. In electron microscopy, peculiar features of ER in some of dysplastic cells was also noted. Genetic examination proved familiar incidence of Cowden's disease in several members. Chromosomal examination of the patient (karyotype 46, XX) was without abnormalities.