Sclerosing odontogenic carcinoma in the maxilla: a rare primary intraosseous carcinoma.

Sclerosing Odontogenic Carcinoma (SOC) was first described by Koutlas et al. in 2008. SOC is a low-grade odontogenic carcinoma, which presents as an expansile radiolucency that causes tooth displacement and root resorption. It is locally aggressive but reports suggest a very low probability of regional or distant metastasis. SOC contains small nests and thin cords of small cuboidal or polygonal epithelial cells with cytoplasmic clearing. Pleomorphism and mitoses are not prominent. Skeletal muscle and perineural infiltration with stromal sclerosis is characteristic. Immunohistochemically, SOC stains for cytokeratins (CK) 5/6 and 19, and e-cadherin. Nuclear staining with p63 is also positive. CK20, carcinoembryonic antigen and CAM 5.2 are negative. We report a rare entity of primary intraosseous carcinoma of the maxilla which has the clinical and histological markers of SOC. Occurrence in the maxilla has been reported only once before in the literature.