Adenomatoid odontogenic tumor: light and electron microscopic study

A case of adenomatoid odontogenic tumor involving the right upper cuspid region of a 17-year-old girl is described. In light microscopy, liminal structures and rosette-like structures were found in the parenchyma of the tumor. Electron microscopic observations revealed that the rosette-like structures were less organized than the luminal structures; the luminal structures are supposed to be associated with secretory activities including the formation of calcified material which show the apatite pattern by electron diffraction. The origin and differentiation of cells constituting the tumor are discussed.