Myoepithelial cell carcinoma of the oral cavity: A case report and review of literature.

Myoepithelial carcinoma (MC) is a malignant salivary gland neoplasm whose tumor cells demonstrate cytologic differentiation toward myoepithelial cells and lack ductal or acinar differentiation. It is a relatively rare tumor and many a times remains undiagnosed because of histopathological heterogeneity. It represents about 0.4-0.6% of all salivary gland tumors and 1.2-1.5% of carcinomas. It occurs predominantly in the parotid gland with a mean age of presentation being 55 years (range 14-86) with no sex predilection. MC appears to be a low grade malignancy when arising in a pleomorphic adenoma, but tends to be more aggressive and has a higher metastatic potential when arising de novo. The clinical behavior of MC is variable and there are no pathologic features that correlate with patients' outcome. Most tumors that display marked cytologic atypia, high mitotic activity and necrosis tend to behave aggressively. The current case is of a 42-year-old male with recurrent tumor mass in the mandibular right posterior region. The purpose of this article was to describe the clinicopathological and immunohistochemical features of intraoral MC and to discuss review of literature of this rare tumor.