The Calcifying Epithelial Odontogenic Tumor (CEOT)is a rare benign odontogenic tumor that was first described by Pindborg.
Clinical features:
(1) slow-growing single gingival mass of the maxilla or mandible
(1a) intraosseous CEOT is more common in the premolar and molar regions of the mandible
(1b) extraosseous CEOT is usually seen in the anterior gingiva
(2) painless and hard on palpation
On X-rays the lesion shows well-defined radiolucency with scattered radiopacities within. Sometimes an unerupted tooth may be associated with the tumor.
Histologic triad:
(1) sheets and nests of polyhedral epithelial cells with prominent interceullular bridges and with variable pleomorphic nuclei
(2) amyloid-like (Congo red positive) material separating epithelial cell sheets
(3) concentric calcifications in the form of Liesegang rings
Other findings:
(1) rarely pigmented
(2) scattered giant cells
(3) prominent nucleoli
(4) rare mitoses
Very rarely malignant transformation may occur.
