Ameloblastomatous calcifying odontogenic cyst: a rare histologic variant

Abstract

Calcifying odontogenic cyst (COC) is an uncommon developmental odontogenic cyst first described by Gorlin in 1962. It is considered as extremely rare and accounts for only 1% of jaw cysts reported. Because of its diverse histopathology, there has always been confusion about its nature as a cyst, neoplasm or hamartoma. Several subclassifications have been proposed. Here, we present a case of calcifying odontogenic cyst with ameloblastic proliferation - an extremely rare histologic variant. The classical histologic features of the lining epithelium in the form of cords and presence of characteristic ghost cells were seen along with ameloblastomatous proliferations. Ameloblastomatous COC microscopically resembles unicystic ameloblastoma except for the ghost cells and calcifications within the proliferative epithelium. The nature of the COC is controversial. The case is presented here for its rarity, and difference between ameloblastomatous COC and ameloblastoma ex COC has been emphasized.

Ameloblastomatous Calcifying Odontogenic Cyst: A Rare Lesion

“…It presents with a painless slowly growing lesion affecting young adults in the second decade of life without gender predilection (4). Kamboj, Aithal, and Ide et al reported cases of ameloblastomatous COC with swelling of mandible, which is inconsistent with our study (1,3,10). In the present study, ameloblastomatous COC occurred in a man in fourth decade of life.…”

“…In the present study, ameloblastomatous COC occurred in a man in fourth decade of life. Aithal and Singh presented female cases in the third decade of life and Menal reported a case of in a man in the third decade (3,8). COC is generally a unilocular radiolucent lesion; some of them are well-defined and others may be ill-defined or poorly defined in radiology (1, 2).…”

“…Some of them have cystic features but others show characteristics of a solid neoplasm (3,5). Therefore, there are some classifications of COC.…”

“…COC is a developmental odontogenic cyst. It is considered as a rare lesion and accounts for 1% of jaw cysts (3). There are heterogeneous groups of COC that demonstrate variable clinical and histopathological features.…”

Ameloblastomatous Gorlin's cyst

“…According to the new WHO classification of histological typing of odontogenic tumors, the COC constitutes a benign cystic neoplasia that presents an epithelium similar to an ameloblastoma, with ghost cells that may display calcifications (9). COC is an uncommon lesion accounting for 1% of jaw cysts (9,10); the ameloblastomatous COC is even less common. Of 43,500 cases diagnosed by the Oral Pathology diagnostic service at the Indiana University School of Dentistry, only 34 cases of COC were reported.…”