Ameloblastic carcinoma of the maxilla.

The maxilla is an unusual site for an ameloblastoma, and certainly for an ameloblastic carcinoma. Ameloblastomas are considered as benign, yet locally aggressive neoplasms in the vast majority of cases. However, very rarely, these tumors demonstrate a clinical course of malignancy. Recently, a classification system was published differentiating between malignant odontogenic carcinoma variants. The two such forms include malignant ameloblastoma, and ameloblastic carcinoma. In the differential diagnosis, the designation of malignant ameloblastoma is reserved for lesions that, despite their benign histology, metastasize as well-differentiated cells. The diagnosis of ameloblastic carcinoma is reserved for tumors that demonstrate a malignant morphologic appearance, regardless of whether metastasis is a proven fact at the time of discovery and treatment. We discuss the presentation, pathology, and treatment of the 18th case of a maxillary ameloblastic carcinoma in the literature.