Surgical management of peripheral variant of adenomatoid odontogenic tumor: A rare case report with review

Adenomatoid Odontogenic Tumor Mimicking a Dentigerous Cyst in Maxilla

Aim

To present a case of adenomatoid odontogenic tumor (AOT) associated with impacted maxillary lateral incisor in a 12-year-old female that mimicked dentigerous cyst.

Background

Adenomatoid odontogenic tumor (AOT) was first mentioned by Steensland in 1905, which is a rare tumor of odontogenic origin. Dreibladt in 1907 coined the term pseudo ameloblastoma. In 1948, Stafne considered it a distinct pathological entity.

Case description

A 12-year-old female reported to the Department of Oral and Maxillofacial Surgery with the chief complaint of progressive swelling on the left maxillary anterior region for 6 months. The clinical and radiographical findings of the case represented a dentigerous cyst or unicystic ameloblastoma, but the histopathological interpretation was interpreted as AOT.

Conclusion

The AOT is an unusual entity that is commonly misdiagnosed as a dentigerous or odontogenic cyst. Histopathology plays a vital role in diagnosis and further management.

Clinical significance

The interest and relevance of the present case are the difficulties in diagnosing accurately based on the radiograph and histopathology. Both dentigerous cysts and AOT are entirely benign and encapsulated lesions, and enucleation poses no major difficulties. The case report highlights the importance of early diagnosis of neoplasm arising in odontogenic tissues. The fact that in cases of unilocular lesions surrounding the impacted tooth in the anterior maxillary region, AOT should also be considered as a differential diagnosis.

How to cite this article

Pawar SR, Kshirsagar RA, Purkayastha RS, et al. Adenomatoid Odontogenic Tumor Mimicking a Dentigerous Cyst in Maxilla. Int J Clin Pediatr Dent 2022;15(6):770-773.

Peripheral adenomatoid odontogenic tumor in a cloak of an epulis: report of a rare case

Background

Adenomatoid odontogenic tumor constitutes an uncommon benign odontogenic tumor which is well-known as “two-thirds tumor” (two-thirds of adenomatoid tumors occur in the maxilla, two-thirds occur in young females, two-thirds of the cases are associated with un-erupted teeth and two-thirds of the affected teeth are canines). Larger part of these present as intra - osseous tumors while peripheral counterparts are extremely rare. Peripheral adenomatoid odontogenic tumor is a unique entity which generally presents as a slow growing gingival swelling with minimal bone involvement. This often leads to its erroneous diagnosis as a simple gingival lesion and the real diagnosis is only revealed after its microscopic evaluation. It exhibits a marked predilection for maxillary gingiva of incisor region and most commonly affects the younger females.

Case presentation

We report a case of 25 years old female patient of African ethnicity who presented with a 2 × 2 cm mass attached to the left mandibular gingiva in cuspid- bicuspid region which is an unusual site for AOT. It was accompanied by slight bone loss. With the differential diagnosis of gingival epulis and peripheral ossifying fibroma; surgical excision was performed. The light microscopic examination of the specimen aided the final diagnosis of Adenomatoid odontogenic tumor with the histopathological features identical to its intra osseous counterpart.

Conclusion

In this case, the tumor is present on the mandibular gingiva in a 25 years old patient which is an atypical location and age for this tumor; also, the only individual case reported in an African patient. Only, a meager number of peripheral adenomatoid odontogenic tumor cases have been logged so far with majority of them occurring in maxillary gingiva. Furthermore, an ambiguity still prevails regarding its true origin and possible biological course. Hence, reporting of similar cases should be encouraged to facilitate the better understanding of its varied epidemiological details and clinical presentation.

Adenomatoid odontogenic tumor: Case series of 14 with wide range of clinical presentation

Background

To present 14 cases of adenomatoid odontogenic tumor (AOT), highlighting their clinical, radiographic, and histologic characteristics.

Material and Methods

Fourteen cases of AOT were retrieved from the archives of the Oral Pathology Biopsy Service (OPBS). Clinical, radiologic, and histologic findings are described.

Results

Fourteen AOT cases were reviewed, of which 12 were intraosseous and two were peripheral (gingiva). The cases came from eight females and six males with an age range of 11–30. Of the 12 intraosseous cases, nine were follicular (associated with impacted teeth), while three were extra-follicular (present between teeth). Six of the 12 cases were in the maxilla, and the other six were in the mandible. The two peripheral cases presented as nodules on the buccal gingiva of the anterior maxillary teeth. Radiographically, all 12 follicular and extra-follicular cases were unilocular radiolucencies; of those, only one had specks of radiopacity. Histologically, all specimens were similar in morphology, demonstrating a varied degree of duct-like structures, epithelial spheres, spindle-shaped epithelial cells, calcifications, and a thick capsule. The two peripheral cases had no capsule.

Conclusions

AOT usually affects patients under 20 years of age, with a female to male ratio close to 2:1. Presentation in the anterior maxilla is almost twice as common as in the anterior mandible. Radiographically, AOT presents as a unilocular radiolucency more commonly associated with impacted teeth, simulating a dentigerous cyst. We present 14 new cases of AOT (nine follicular, three extra-follicular, and two peripheral) with discussions of their clinical, radiographic, and histological features.

Key words:Adenomatoid, odontogenic, tumor.

The adenomatoid odontogenic tumour: an update of selected issues

The aim of this update was to present the recent notable progress within remaining questions relating to the adenomatoid odontogenic tumour (AOT). Selected issues that were studied included the following: (i) AOT history and terminology, (ii) the so-called peripheral AOT, (iii) AOT and the gubernaculum dentis and (iv) the so-called adenomatoid odontogenic cyst (AOC). The earliest irrefutable European case of AOT was described in 1915 by Harbitz as 'cystic adamantoma'. Recently, Ide et al. have traced two Japanese cases with irrefutable proof described by Nakayama in 1903. The so-called peripheral (gingival) variant of AOT seems to cover a dual pathogenesis, both an 'erupted intraosseous' and an 'extraosseous' (gingival) one. In 1992, we theorized that the generally unnoticed gubernaculum dentis (cord and canal) seems to be involved in the development of AOT. Ide et al. have concluded that the dental lamina in the gubernacular cord seems to be an embryonic source of the vast majority of AOTs. The suggestion by Marx and Stern to change the nomenclature of AOT to adenomatoid odontogenic cyst (AOC) is critically discussed. The present authors agree on the background of the work of several groups of researchers and WHO/IARC classifications that the biology of the follicular variant of AOT is already fully explained and does not make room for any change in diagnostic terms. Further, there is no reason to change terminology in this case where improvements or conditions to better clinical management are not an issue.