How to name it: a rare case of odontogenic cyst

Orthokeratinized odontogenic cyst: A large series and comprehensive literature review with emphasis on synchronous multiple occurrence and neoplastic transformation

OBJECTIVES

The objective of this study was to demonstrate the clinical, radiologic, and histologic features of orthokeratinized odontogenic cyst (OOC); determine the characteristics of multiple OOCs; and present rare but significant manifestations of OOC.

STUDY DESIGN

A clinical, radiologic, and histopathologic study of 65 primary and 2 recurrent OOC cases was performed retrospectively along with a comprehensive literature review.

RESULTS

OOCs shared similar radiologic findings with odontogenic keratocyst, yet some showed features that have not been previously described: root resorption and radiopaque foci. Histologic review revealed a unique histiocytic lining and some findings suggestive of the multipotentiality of the odontogenic epithelium. The analysis of patients with multiple OOCs demonstrated that multiple OOCs occurred synchronously with a marked predilection for young male adults. Two unusual cases were also identified: an OOC combined with a BRAF^V600E ameloblastoma and a recurrent OOC with malignant transformation.

CONCLUSIONS

This largest series presents previously unreported radiographic and histopathologic features that can be seen in OOC. Multiple OOCs have clinical characteristics distinct from those of solitary cases. The first reported OOC associated with ameloblastoma suggests the involvement of oncogenic mutations in odontogenic tumorigenesis. Although OOC shows a low recurrence rate, the possibility of malignant transformation of recurrent OOCs should be emphasized.

Glandular odontogenic cyst associated with ameloblastoma: Case report and review of the literature

Glandular odontogenic cyst (GOC) associated with ameloblastoma is an exceedingly rare histologic presentation with no known clinical significance or treatment applications. Four cases have been reported, three in the mandible and one in the maxilla. The age range is 14-65 and with male predilection. All four presented with swellings and two with pain. We add one more case to the literature of a 58-year old male presenting with an expansile multilocular radiolucency between teeth #19-23. The ameloblastomatous changes in this case are consistent with those of a unicystic ameloblastoma-mural subtype. Although the histologic changes are those of a unicystic ameloblastoma, the clinical and radiographic findings are not. This case therefore presents a clinical challenge with regards to treatment planning for recurrence and prognosis. We conclude that treatment for GOC therefore be based on individual clinical presentation.

Key words:Glandular odontogenic cyst, GOC, ameloblastoma, unicystic ameloblastoma, mural unicystic ameloblastoma.

Report of Two Cases of Combined Odontogenic Tumors: Ameloblastoma with Odontogenic Keratocyst and Ameloblastic Fibroma with Calcifying Odontogenic Cyst

Combined odontogenic neoplasms have rarely been documented. Such tumors have also been described by other researchers as "hybrid" lesions. The histologic features are often identical to other individually well-established odontogenic neoplasms such as ameloblastoma, adenomatoid odontogenic tumor, ameloblastic fibroma (AF), and ameloblastic fibro-odontoma. Their clinical presentation is variable, ranging from cysts to neoplasms showing varying degrees of aggressive behavior. Most combined tumors contain features of one of the odontogenic tumors in combination with either a calcifying odontogenic cyst (COC) or a calcifying epithelial odontogenic tumor. We present two new cases of combined odontogenic tumors: an ameloblastoma with an odontogenic keratocyst and an AF with COC. Predicting clinical outcome is challenging when a combination tumor is encountered due to the paucity of such lesions. One must understand salient features of these entities and differentiate them from the more common conventional neoplasms to expand classification and provide prognostic criteria.