Update on Odontogenic Tumors: Proceedings of the North American Head and Neck Pathology Society

Abstract

Odontogenic tumors are rare entities, often derived from the epithelial remnants in the gnathic bones following odontogenesis. This brief manuscript will seek to address recent developments pertaining to odontogenic tumors as well as particularly uncommon odontogenic tumors and the difficulties in their diagnosis.

Keywords: Adenoid ameloblastoma; Adenomatoid odontogenic tumor; Ameloblastoma; Calcifying epithelial odontogenic tumor; Next generation sequencing; Odontogenic tumors.

Fig. 1

A schematic of signaling pathways implicated in the pathogenesis of odontogenic tumors

Fig. 2

a Hematoxylin and eosin of a recurrent follicular ameloblastoma previously treated with curettage. b BRAF V600E immunohistochemical staining exhibits positivity

Fig. 3

Hematoxylin and eosin of an adenomatoid odontogenic tumor presenting in an 18 year-old female around the crown of an impacted canine. Spindled epithelial cells are arranged in sheets with whorls and focal rosette formation. Amyloid deposition is present with displacement of calcified massed leading to sectioning artifact

Fig. 4

a Hematoxylin and eosin of a calcifying odontogenic cyst/calcifying cystic odontogenic tumor exhibiting abundant ghost cells as well as ameloblastic epithelium bβ-catenin exhibits nuclear positivity in tumoral cells c LEF-1 exhibits nuclear positivity in tumor cells as well as pre-B and T lymphocytes

Fig. 5

a Hematoxylin and eosin of adenoid ameloblastoma demonstrating at low power a cribriform architecture, with subtle palisading of the cells at the periphery of the tumor nests. Amorphous, anucleate areas representing ghost cell keratinization (solid arrow) are present, as well as more basophilic areas of cellular condensation or morules (open arrow). b In other more solid areas, cellar clearing is noted with masses of dentinoid

Fig. 6

a Calcifying epithelial odontogenic tumor exhibiting sheets of polygonal epithelial cells with interspersed amyloid and concentric calcifications. b A focal area of calcifying epithelial odontogenic tumor-like change in the wall of a hyperplastic dental follicle surrounding an impacted mandibular molar in a 14 year-old male. c A focal calcifying epithelial odontogenic tumor-like area occurring in an adenomatoid odontogenic tumor in a 21 year-old female in the anterior maxilla. d Hematoxylin and eosin of amyloid rich variant of central odontogenic fibroma. Abundant amyloid is present with small islands of odontogenic epithelium