The eosinophilic material in adenomatoid odontogenic tumor associated with amyloid protein component

Objective: To investigate the relation betweeneosinophilic materials and amyloid P (AP) component inadenomatoid odontogenic tumor (AOT). Methods: Theexpression of amyloid proteins and basement membraneproteins, including type tV collagen, laminin andheparin sulfate proteoglycan (BSPG), in AOT wereanalyzed by immunohistochemical method. Results:Most eosinophilic droplets among tumor cells and someepithelial cells showed positive stain for AP component.The immunoreactiolls of type tV collagen and lamininwere only found in blood vessels of this tumor. Thetumor calls and eosinophilic materials in duct-likestructures were constantly unstained for both amylbidand basement membrane proteins. Present resultssuggest that the nature and composition of eosinophilicdroplets may differ from the eosinophilic layer in ductlike structures. This study first demonstrated that theamyloid-like deposition in AOT is associated with APcomponent by immunohistochemical method. It supported that AP component may be epithelial origin sincethe AP immunolocalization was found in tumor cells.