PERIPHERAL DESMOPLASTIC AMELOBLASTOMA IN THE MANDIBLE

The peripheral ameloblastoma, desmoplastic histologic type, is a rare, benign tumor among the odontogenic tumors. Both the mandible and maxilla can be affected; it is characterized by slow growth, and usually is asymptomatic. A 58-year-old male patient was referred presenting with a painless nodule in the gingiva. Intraoral examination revealed an extraosseous submucosal nodule with 10 × 10 mm located at the mucus-gingival junction on the right side of the mandible. An excisional biopsy was performed. Microscopy showed a desmoplastic stroma that compressed the tumor epithelial cells within islands and a myxoid stroma surrounding the tumoral nests. Cytokeratin AE1, cytokeratin AE3, and p63 were positive, Ki-67 was low (