ORAL
and maxillofacial pathology diagnosis and management—from page 280
Calcifying Epithelial Odontogenic Tumor, Multifocal Discussion The calcifying epithelial odontogenic tumor (CEOT) (or “Pindborg tumor”) represents a rare, benign odontogenic neoplasm. Its exact histogenesis is uncertain, although an origin from the stratum intermedium or dental lamina has been proposed.1 The tumor exhibits a predilection for the posterior mandible, with a peak age at diagnosis in the 4th decade and no significant gender predilection.2,3 Most patients exhibit a painless, slowly enlarging swelling. The majority of cases are intraosseous, although peripheral (i.e., gingival soft tissue) lesions also are possible. Radiographic examination shows a unilocular to occasionally multilocular radiolucency, often with associated opacification. Other possible findings include cortical bone resorption or perforation
322
and tooth displacement.2 Many examples develop in association with an impacted tooth, especially a mandibular molar.1 The differential diagnosis for a mixed radiopaqueradiolucent lesion associated with the crown of impacted tooth may include other odontogenic tumors that produce calcification, including calcifying odontogenic cyst, ameloblastic fibro-odontoma, and adenomatoid odontogenic tumor. Ameloblastic fibroodontoma and adenomatoid odontogenic tumor tend to occur in somewhat younger patients compared to CEOT. Both CEOT and ameloblastic fibro-odontoma exhibit a predilection for the posterior mandible. In contrast, adenomatoid odontogenic tumor most often occurs in the anterior maxilla, and the calcifying odontogenic cyst exhibits an approximately even distribution between the maxilla and mandible. In
Texas Dental Journal | Vol 139 | No. 6
addition, depending on the amount of calcification, some CEOTs may appear entirely radiolucent. In the present case, the lesion in the mesiolateral root area of the mandibular second premolar appeared entirely radiolucent, and the radiographic differential diagnosis included primarily a lateral periodontal cyst or odontogenic keratocyst. As exemplified by the current case, typical microscopic findings of CEOT include a proliferation of eosinophilic epithelial cells with associated pools of an amyloid protein. This material exhibits applegreen birefringence with Congo red staining and may form basophilic, lamellar calcifications (Liesegang ring calcifications). Investigators have identified odontogenic ameloblast-associated protein (ODAM) within the amyloid deposits of CEOT; this protein has been implicated in
