Immunohistochemical study in two cases of dysplastic gangliocytoma of cerebellum (Lhermitte-Duclos disease).

We report here immunohistochemical study of two cases of dysplastic gangliocytoma of cerebellum (Lhermitte-Duclos disease) a rare entity which is recently classified as a tumor but which hamartomatous nature is also considered. Dysplastic cells of our cases expressed neuronal markers (synaptophysin and NFP), thus their origin from neurons or neuronal precursor is clearly demonstrated. The exact progenitor cell is, however, unknown. The glial involvement was not easily judged based on our histochemical study. While a few GFAP-immunopositive astrocytes were seen in all specimens, including the recurrence of the first case, they appeared of normal size and non hypertrophic in the second case. Furthermore, they did not much increased in number in the recurrent tumor. Thus, it seems that they are not the primary target for the pathogenetic process, whatever it is, of Lhermitte-Duclos disease.