Adenomatoid Dentinoma: Case Report and Review of a Rare Odontogenic Lesion

Odontogenic Carcinoma With Dentinoid in Long-Term Follow-up With 2 Recurrences

Dentinoid has been mentioned as a frequent component in several types of benign odontogenic tumors; however, there are some other very rare dentinoid-producing odontogenic tumors that have been described, which are not recognized in the current World Health Organization Histological Classification of Odontogenic Tumours. In this context, we report an unusual malignant odontogenic tumor containing dentinoid located in the left maxilla of a 41-year-old man. The lesion was initially diagnosed and treated as a cemento-ossifying fibroma. After 7 years, a tumor was noted at the same location and was diagnosed as pleomorphic adenoma. The patient developed a new lesion 2 years later. Histological features included an epithelial proliferation of basaloid and clear cells, some with peripheral palisading, which were scattered both in a fibrous stroma and within an amorphous eosinophilic dentinoid product. Because of doubts about the first 2 diagnoses and the current situation, all histopathological slides were reviewed in our service as a consultation case, and the findings were consistent with the diagnosis of an odontogenic carcinoma with dentinoid. Immunohistochemical analysis was performed and an ultrastructural study by scanning electronic microscopy and energy-dispersive X-ray microanalysis was made to characterize dentinoid material. After 1 year of follow-up, the patient is alive and free of the disease. This case highlights the wide variability regarding cytological evidence of malignancy, and adds a new case of odontogenic carcinoma with dentinoid, which represents a distinct entity with locally aggressive behavior and should be considered be included in a future World Health Organization Histological Classification of Tumours.

A rare case report of an adenomatoid odontogenic tumor associated with odontoma in the maxilla

INTRODUCTION

The adenomatoid odontogenic tumor (AOT) associated with odontoma has been described as a new entity with overlapping features of adenomatoid-like structures and odontoma. Presentation of the case: We report the second case of AOT associated with odontoma in the posterior maxillary region. A 22-year-old patient presented expansion of the vestibular and palatine cortical wall of maxilla. Radiographic examination and computed tomography confirmed erosion of maxillary walls, root resorption, displacement of a neighboring tooth and radiopacities within the lesion. Histopathological analysis showed a cystic cavity lined by odontogenic epithelium, organized as duct like structures and tubular dentin. The diagnosis established was AOT associated with odontoma.

DISCUSSION

As fewer cases have been described, the aim of this study is to report clinical behavior and evolution of adenomatoid odontogenic tumor associated with odontoma, as it have not yet been described and its origin is not completely established. The hamartomatous or neoplastic origin of this tumor is under debate.

CONCLUSIONS

Therefore, it is necessary similar cases to be published to increase the knowledge about the clinical behavior and evolution of this tumor, to enable such lesions to be more clearly defined in the next classification of odontogenic tumors.

Odontogenic carcinoma with dentinoid: a new odontogenic carcinoma

Dentinoid is an integral part of some odontogenic tumors. This article describes the clinico-pathological features of three cases of odontogenic carcinomas with dentinoid (OCD). A comparison of these with previously reported cases of dentinoid-producing epithelial odontogenic tumors allowed us to identify another six cases that may be considered as examples of OCD. Six cases occurred in the mandible and three in the maxilla, all developing behind the canines. There was no sex predilection (five men and four women; age range 14-61 years, mean 38.1). Pain or discomfort was mentioned in five cases, four of which showed tooth resorption. All cases appeared initially as well-defined radiolucencies, five of which showed variable amounts of calcified material. Recurrences were recorded in three instances, but no evidence of metastasis has been found. Seven cases were composed predominantly or entirely of clear cells, usually with minimal cellular atypia and variable mitotic activity; however, in all cases there was evidence of tumor infiltration into adjacent tissues, including the presence of perineural invasion in two tumors. Those cases in which no reference was made to the presence of clear cells exhibited evident mitotic activity and cellular pleomorphism. The epithelium in OCD does not produce buds or enamel organ-like structures such as those found in ameloblastic fibro-dentinoma and this tumor does not contain a mesenchyme-like connective tissue resembling dental papilla as observed in several mixed odontogenic tumors. Based on the existing data and the present series of cases, OCD appears to represent a distinct entity.

Adenomatoid odontogenic tumor associated with odontoma: a case report and critical review of the literature

We describe a case of adenomatoid odontogenic tumor (AOT) associated with odontoma occurring in the posterior mandible of a 32-year-old man. Although calcifications are commonly found in the AOT, the presence of rudimentary dental structures is a very rare phenomenon. Cases with similar aspects have been described as ameloblastic dentinoma, ameloblastic odontoma, adenoameloblastic odontoma and AOT associated with odontoma. After a careful analysis of the literature we describe the clinical aspects of this tumor. Further case reports and surveys of odontogenic tumors are necessary to define whether AOT associated with odontoma is a variant of AOT or a distinct clinicopathologic condition.