Calretinin expression in ameloblastomas

Abstract

The biological significance of calretinin expression in ameloblastomas is not known and its use as a distinctive, specific immunohistochemical marker for ameloblastic tissues remains to be confirmed. However, the results of this study raise the possibility that calretinin may be an important diagnostic aid in the differential diagnosis of cystic and solid ameloblastic tumours.

Adenomatoid Odontogenic Tumor (AOT) Originating in a Unicystic Ameloblastoma: A Case Report

“…The histology although not diagnostic, was consistent with this diagnosis. Confirmation of the diagnosis of ameloblastoma was provided by the calretinin immunohistochemistry, which showed a characteristic pattern of positive staining of the cyst lining [20,21]. Previous unpublished work in our department has shown that AOTs do not stain with calretinin neither in the solid areas nor in the cyst linings [22].…”

Primordial Odontogenic Cyst with Induction Phenomenon (Zonal Fibroblastic Hypercellularity) and Dentinoid Material Versus Archegonous Cystic Odontoma: You Choose!

“…The following diagnostic interpretations were provided: Odontogenic cyst not otherwise specified (NOS) (1), true POC (1), mandibular cyst with ameloblastic changes (1), and unicystic ameloblastoma (2). The senior author of this paper felt uncomfortable with the diagnosis of ameloblastoma, therefore the diagnosis of odontogenic cyst NOS was rendered with the comment that it may represent an example of true POC with areas of stromal induction and dentinoid formation.…”

“…Interestingly, calretinin appears to be a specific immunohistochemical marker for neoplastic ameloblastic epithelium since it has been identified in 93.5 % of multicystic and 81.5 % of unicystic ameloblastomas [2] but not in odontogenic cysts [3]. In the study by DeVilliers et al [4] comparing the calretinin immunohistochemical profile of ameloblastomas and OKCs (KCOTs), it was concluded that all (19/19) ameloblastomas were positive in contrast to 0/17 of the OKCs (KCOTs).…”

“…Multiple sections were evaluated and the epithelial features were consistent in all sections. Be that as it may, to further investigate the possibility of ameloblastoma, multiple sections were immunohistochemically assessed for calretinin which can be identified in ameloblastomas but not in odontogenic cysts [2][3][4][5]. Besides calretinin, and in order to erase any doubt regarding the fibroblastic origin of spindle cells in the subepithelial induction-like zone, immunohistochemical staining for S100 protein and smooth muscle actin (SMA) were performed.…”

The Diagnostic Usefulness of Immunohistochemistry for Odontogenic Lesions

“…CD56 (or NCAM) is expressed in the peripheral cells of the tumor islands in all types of ameloblastoma ( Fig. 1e) [19,20], while calretinin is reciprocally expressed in the stellate reticulum-like cells [21,22], including in most unicystic ameloblastoma (although less frequent than in solid ameloblastoma [21,23]). However, both markers are expressed, to a much lesser extent, in odontogenic keratocyst/KCOT, thus using markers in isolation to distinguish a cystic ameloblastoma from odontogenic keratocyst (OKC)/keratocystic odontogenic tumor (KCOT) may still result in diagnostic uncertainty [20,24].…”