Glial choristoma in the oral cavity: histopathologic and immunohistochemical features.

This report describes the morphologic and immunohistochemical features of two cases of glial choristoma arising in the palate. The bulk of the lesions consisted of mature neuroglial tissue admixed with salivary glands, adipose tissue and lymphoid aggregates in case 1 and of cartilage, bone and foci of smooth muscle cells in case 2. In addition, case 2 showed choroid plexus and melanin-containing epithelium. Neuroglial tissue was intensely positive for CD57 as well as for glial fibrillary acidic protein, S-100 protein and vimentin. Neuron-specific enolase and neurofilament were focally or weakly positive. Proliferating cell nuclear antigen was negative in case 1 but sparsely positive in case 2. These features reflect the fact that glial choristoma is a developmental malformation of heterotopic central nervous tissue with limited growth potential.