Granular cell tumor and congenital epulis of the newborn : immunohistochemical and ultrastructural observations relating to histogenesis

ABSTRACT

Granular cell tumor and congenital epulis of the newborn are two lesions rarely round in the oral cavity whose histogenetic origin is highly controversial despite their uniform morphologic appearance. This study was performed in attempt to determine their histogenesis using immunohistochem-ical techniques with different antibodies for several markers such as neurone-specific enolase [NSE], S100, Vimentin and CD68. All of the granular cell tumor cases were positive for all studied markers. On the other hand, congenital epulis cases were only positive for Vimentin and CD6H. These results suggested a neural and/or neuroectodermal origin for granular cell tumor cases hut not for congenital epulis cases. The positivity for CD68 in all studied cases suggested a phagocytic origin of the granular cells in the two lesions investigated in this study as proven ultrastructurally by the p jsence of numerous phagolysosomes and autophagic vacuoles