Adenoid Ameloblastoma: The Newly Recognized Odontogenic Tumor - A Case Report

Abstract

Adenoid ameloblastoma is a newly recognized epithelial odontogenic tumor. Herein, we present the case of a 24-year-old male patient who exhibited swelling in the anterior region and right hemi-mandible. Computed tomography demonstrated the presence of a hypodense osteolytic lesion associated with an impacted tooth. Based on the clinical hypotheses of the dentigerous cyst, odontogenic keratocyst, and ameloblastoma, an incisional biopsy was performed, and the diagnosis of ameloblastoma was rendered. A surgical resection of the tumor was performed. Histopathological examination of the specimen revealed typical areas of ameloblastoma associated with ductiform structures and cell proliferation in a solid storiform pattern, features resembling those found in adenomatoid odontogenic tumor. Based on these findings, the diagnosis of adenoid ameloblastoma was rendered. The accurate diagnosis of this locally infiltrative tumor is essential due to its similarity to other odontogenic neoplasms.

Keywords: Adenomatoid Odontogenic Tumor; Ameloblastoma; Odontogenic Tumor.

Fig. 1

Clinical aspects of the adenoid ameloblastoma. (A and B) Extraoral clinical appearance revealed swelling in the anterior region and right hemi-mandible, which caused the facial asymmetry. (C and D) Computed tomography images demonstrate the presence of a hypodense osteolytic lesion associated with an impacted tooth, which caused bulging, thinning, and destruction of cortical bone, as well as root resorption and tooth displacement

Fig. 2

Histopathological features of the incisional specimen of ameloblastoma (Hematoxylin and Eosin). (A) Proliferation of odontogenic epithelial cells and connective tissue stroma (Magnification: ×100). (B) Epithelial cords show peripheral columnar and cuboidal cells in a palisade arrangement and exhibit hyperchromatic nuclei and inverted polarity. The odontogenic epithelial cells in the central area were loosely arranged (Magnification: ×400)

Fig. 3

Histopathological features of the excisional specimen of adenoid ameloblastoma (Hematoxylin and Eosin). (A) Odontogenic epithelium with a plexiform pattern (Magnification: ×100). (B) Solid pattern of odontogenic epithelial cells exhibiting whorled areas and scant fibrous stroma (Magnification: ×100). (C) Island of odontogenic epithelium with spindle-shaped cells at the periphery and clear cells in the center. The island was surrounded by odontogenic epithelium with a plexiform pattern (Magnification: ×100). (D) Odontogenic epithelial cells in a cribriform pattern (Magnification: ×100). (E) Cords and solid areas formed by odontogenic clear cells (Magnification: ×400) (F) Odontogenic epithelial cells forming duct-like structures (Magnification: ×400). (G) Rosette-like structures with the central space containing variable amounts of amorphous material and cells exhibiting anisocytosis and nuclear hyperchromatism (Magnification: ×400). (H) Anastomosing cords of odontogenic epithelium bounded by cuboidal odontogenic clear cells and hyalinization adjacent to the epithelial cords (Magnification: ×400)