Primary intraosseous carcinoma of the mandible: A case report with literature review

Primary intraosseous carcinoma (PIOC) is a rare tumor that has been infrequently reported. Some diagnostic criteria have been proposed to consider a lesion as PIOC: (1) absence of ulcer in the oral mucosa overlying the tumor, (2) absence of another primary tumor at the time of diagnosis and for at least 6 months during the follow-up, and (3) histological evidence of squamous cell carcinoma. The etiology is not clear, although odontogenic embryonic origin has been reported. Probably, PIOC derives from the remnants of odontogenic tissue, either the epithelial rests of Malassez or the remnants of the dental lamina.