Clinical presentation and histologic observations of a combined epithelial odontogenic tumor which contained foci diagnostic for both calcifying odontogenic cyst (COC) and adenomatoid odontogenic tumor (AOT) were reported.
Dreibladt, in 1907, first reported the adenomatoid odontogenic tumor (AOT) and Stafne separated it as a distinct of odontogenic tumor. The calcifying odontogenic cyst (COC) was presented as a distinct by Gorlin and his colleagues in 1962. These two different odontogenic lesions have not been reported previously as occurring simultaneously.
A 71-year-old man was admitted on Nov. 15, 1983 with progressive swelling of the maxilla. Radiographs showed radiolucent lesion, but did not present an impacted tooth in the area of the lesion. The tumor was removed by partial maxillectomy.
Histologic observations were revealed that the tumor consisted of four types of cells: odontogenic epithelial cells with ghost cells, low columner adenomatoid cells, proliferative odontogenic epithelial cells and spindle flattened cells. These findings strongly supported the hypothesis that COC and AOT may originate from odontogenic epithelia of the tooth bud.