Ghost cell odontogenic carcinoma arising from calcifying cystic odontogenic tumor: a case report

Abstract

Ghost cell odontogenic carcinoma (GCOC) is an exceptionally rare and malignant odontogenic tumor with aggressive growth characteristics. We describe a case of GCOC which was considerably derived from a previously resected calcifying cystic odontogenic tumor (CCOT). Cellular atypia, mitotic activity, Ki-67 labeling index and matrix metalloprotease-9 positive expression rate were all increased in the currently resected specimen compared to the initial one. This is a rare case of malignant transformation of CCOT to GCOC with respect to its histopathological and immunohistochemical findings.

Keywords: Calcifying cystic odontogenic tumor; Ghost cell odontogenic carcinoma.

Fig. 1

Calcifying cystic odontogenic tumor. (A) Histopathologic examination shows the epithelial lining is composed of columnar or cubical cells, and the nuclei of which are barrier-ranged. Sporadic or conglobate ghost cells are seen in the lining epithelium. (B) Immunohistochemistry shows the Ki-67 is sparsely expressed in tumor cells but negatively in ghost cells, and (C) matrix metalloprotease-9 (MMP-9) is sparsely expressed in tumor cells and interstitium but negatively in ghost cells (Ki-67 and MMP-9 marker).

Fig. 2

Panoramic X-ray film shows a nonopaque lesion located between the right upper lateral incisor and second premolar. The absorption of the root apex could be detected in the involved teeth.

Fig. 3

Ghost cell odontogenic carcinoma. (A) Histopathologic examination shows epithelial cell nests in tumor tissue. (B) Tumor cells are admixed with anucleate ghost cells. Inset: Several tumor cells show atypical mitoses. (C) The tumor cells invade the surrounding vessel. The tumor cells infiltrate into the adjacent fibro-vascular tissue. The clusters of ghost cells are diffusely distributed in the tumor nests. (D) Immunohistochemistry shows the Ki-67 is strongly expressed in the tumor cells but negatively in ghost cells, and (E) matrix metalloprotease-9 (MMP-9) is strongly expressed in interstitium, weakly in the tumor cells but sparsely in ghost cells (Ki-67 and MMP-9 marker).