Ameloblastic odontosarcoma (ameloblastic fibro-odontosarcoma) in the mandible.

A case of ameloblastic odontosarcoma (ameloblastic fibro-odontosarcoma) originating in the mandible is reported. The patient was a 23-year-old Japanese male with diffuse swelling of the mandible from the left premolar to the ramus region. A biopsy specimen showed the histopathological features of ameloblastic fibrosarcoma. Histologic examination of the surgical specimen revealed various amounts of dysplastic dentin and dentinal matrix which were closely associated with both mesenchymal and epithelial components throughout the lesion. In addition, a small amount of abortive enamel matrix, which was in close contact with ameloblastoid cells of epithelial nests, was found by extensive sampling of the resected specimen. Therefore the present case was diagnosed as ameloblastic odontosarcoma. After 2 years, the patient died of uncontrollable local recurrence and extension to the cranial base.