Radiographic and histopathologic features of conventional CEOT. A. A well-demarcated mixed radiolucent and radiopaque lesion is seen in the madible between the left canine and the first molar in close association with an unerupted premolar (case 5). B. The tumor was composed of masses of polyhedral epithelial cells with some eosinophilic amyloid-like surrounding material. Calcium salts were diffusely deposited. (HE, ×100). The tumor cells of conventional CEOT have distinct intercellular bridges and are irregular in shape with pleomorphic nuclei. (insert, HE, × 400). C. Eosinophilic amyloid-like surrounding material is positive for Congo red staining. Some amyloid-like material is undergoing calcification. (Congo red, ×200). D. Langerin positive cells scatter in the epithelial mass. (IHC, ×400).