Radiographic and histopathologic features of Langerhans cell variant of CEOT. A. Radiographic examinations revealed unilocular, well defined, radiolucent areas from the right central incisor to the left first premolar. There were no radiopaque foci in the lesion. Resorption of the left central and lateral incisor was detected (case 1). B. A multilocular radiolucent lesion without a definite sclerotic border in part area from the left canine to the right second molar. No radiopaque foci were found and the roots of the right canine to the first molar were resorbed (case 2). C. The tumor was composed of small nests or strands of odontogenic epithelial cells and amorphous eosinophilic globules of amyloid-like materials in a loose fibrous connective tissue stroma. (HE, ×100) The small epithelial islands were composed of eosinophilic cytoplastic polyhedral tumor cells and a few clear cells. (insert, HE, ×400). D. The globular masses of homogeneous eosinophilic material is positive for Congo red staining (Congo red, ×200) and showed apple green birefringence when subjected to polarized light (insert, Congo red, ×200). E. Moderate chronic inflammatory cells in the fibrous connective tissue. (HE, ×200). F. Langerin-positive cells are seen in islands of epithelium, a higher Langerhans cells to epithelial tumor cells ratio can be seen (IHC, ×400).