AMELOBLASTIC fiBRO-ODONTOMA: A DISTINCT ENTITY

Abstract

Background Ameloblastic fibro-odontoma (AFO) is a benign odontogenic tumor first described by Hooker in 1967. Its etiology and behavior have long been debated, as some investigators have proposed that AFO may represent a stage in development of an odontoma. For this reason, AFO was eliminated from the most recent Odontogenic and Maxillofacial Bone Tumor section of the World Health Organization (WHO) Head and Neck classification system. Occasional AFOs, however, have been found in patients older than the proposed age for odontoma completion (22 years) or present as large radiolucent lesions consisting mainly of the ameloblastic fibroma (AF) pattern with only foci of mineralized product formation. Herein, we present seven cases of AFO, all of which demonstrate particularly aggressive radiographic and/or histopathologic features and do not support the contention that all AFOs represent maturing odontomas. Materials and Methods An IRB-approved retrospective search of the oral pathology biopsy services at the Universities of Kentucky and Florida between January 1, 1975 and January 1, 2018 was completed. Cases with appropriate histopathological and radiographic documentation were selected. Results Seven patient cases were identified with ages 8, 8, 12, 16, 17, 27, and 29 years. Six cases were from the posterior mandible, and one was located in the posterior maxilla extending into the maxillary sinus close to the floor of the orbit. Only two of the cases have follow-up information, both of which demonstrate no evidence of tumor following conservative treatment. Conclusion Although the majority of cases diagnosed as AFO likely represent developing odontomas, we present seven cases in which the clinical, histopathologic, and/or radiographic features suggest that AFO should exist as a distinct entity and be treated similarly to an AF.