Clear cell variant of intraosseous calcifying epithelial odontogenic tumor: a case report and review of the literature.

CEOT is a rare benign, but locally aggressive odontogenic tumor, and some authors have claimed that the biologic behavior of the clear cell variant is even more aggressive, with greater propensity to recur. We report a rare case of clear cell calcifying epithelial odontogenic tumor (CEOT) and discuss its possibly aggressive behavior. A 40-year-old woman experienced an asymptomatic expansion of the left posterior mandible. After radiographic examination and biopsy, a block resection was performed. Histologic examination included analysis of Ki-67 reactivity as a marker of tumor growth activity. Ki-67 labeling was pronounced in the non-clear cell population in the tumor periphery but low in the central and clear cell portions. Clinical and radiographic follow-up 6 years after resection has not revealed any signs of recurrence. On the basis of a review of the literature and our own findings, there is no clear data to suggest that clear cell CEOT exhibits more aggressive behavior compared with conventional CEOT.