Large calcifying epithelial odontogenic tumor with extension into the maxillary sinus: a case report.

Calcifying epithelial odontogenic tumor (CEOT) is a rare, locally invasive neoplasm characterized by the presence of amyloid material that can become calcified. It often is found in the posterior region of the mandible. Such tumors in the maxilla and those that invade the maxillary sinus are extremely rare. This article presents the sixth reported clinical case of a CEOT that invaded the maxillary sinus and extended to the interior of the nasal cavity. The tumor had grown toward the sinus roof, but there was no association with an impacted tooth. Histopathologically, the tumor was composed of plates of polyhedral epithelial cells with highly eosinoplilic cytoplasm, nuclear polymorphism, clear-cell contours, and intercellular bridges in fibrous conjunctive tissue. Amorphous eosinophilic material and diverse calcifications permeated the epithelial cells.