Cytogical features of calcifying epithelial odontogenic tumor (Pindborg tumor) with abundant cementum-like material.

Calcifying epithelial odontogenic tumor (CEOT) is a rare tumor, most frequently occurring in the mandible and composed of large sheets of epithelial cells, sometimes showing nuclear pleomorphism. This paper was aimed at reporting of the cytological features of an unusual case of CEOT, affecting a 14-year-old female, with abundant deposition of intercellular calcified material. The cytological preparations were characterized by large clusters of scarcely cohesive, large polyhedral cells and abundant calcified material. The latter consisted of intensely basophilic substance either in large clusters or discrete concretions and, at high-power view, occasional tumor cells also contained calcified material. Histologically, the uncalcified stroma displayed focal Congo Red positivity with the typical birefringence under polarized light. The neoplastic cells were consistently immunoreactive for epithelial membrane antigen, vimentin and, to a lesser extent, for wide spectrum cytokeratins (AE1 AE3) and cytokeratins 8-18 and 19. The cytological features of CEOT are rather characteristic, and the detection of intra- and extracellular calcifications may help to differentiate this neoplasm from others that most commonly arise in this area.