Adenomatoid odontogenic tumor: a report of a rare case with recurrence.

Adenomatoid odontogenic tumor (AOT) is an uncommon tumor of odontogenic origin, composed of odontogenic epithelium in a variety of histoarchitectural patterns, and characterized by slow but progressive growth. Generally, recurrences seldom, if ever, occur after surgical curettage, while here we report an extremely rare case of AOT with recurrence. The patient was a 36-year-old Chinese man who presented with a palpable bony-hard swelling in the anterior maxillary region initially at the age of 16 and the lesion recurred twice over a 20-year period. The tumor was diagnosed as AOT with well-defined unilocular radiolucency shown in X-ray graphs and solid nodule of cuboidal or columnar cells of odontogenic epithelium forming typical nests or rosette-like structures as well as characteristic duct-like spaces in histologic findings.