Sarcomatous overgrowth in recurrent ameloblastic fibrosarcoma.

A case of recurrent ameloblastic fibrosarcoma (AFS) in the mandibular molar region of a 22-year-old male is reported. The tumor was first diagnosed as a sarcoma of undetermined origin, because the benign epithelial component of AFS had disappeared after repeated surgical procedures. The lesion grew rapidly in the time from hospital admission until operation, suggesting progression from low to high malignancy. The correlation between the benign epithelial component and malignancy is discussed.