Granular-cell tumours: an immunohistochemical study.

The granular cell tumour (myoblastoma, Abrikosoff's tumour) and the congenital epulis in newborns (Neumann tumour) are two lesions rarely found in the oral cavity, whose histogenetic origin is highly controversial. This work analyses using immunohistochemical techniques 15 cases of myoblastomas and two of congenital epulis with different mono- and poly-clonal antibodies. Positive immunostaining was found for S-100 protein and neuron-specific enolase in all the cases of myoblastoma, and for vimentin and carcinoembryonic antigen in some cases. No immunoreactivity was observed for any of the other 13 antibodies used in congenital epulis.