Sebaceous Epithelial-Myoepithelial Carcinoma With Aggressive Behavior and Evidence of Preexisting Pleomorphic Adenoma.

Epithelial-myoepithelial carcinoma (EMCA) is a rare low-grade carcinoma of the salivary glands with multiple morphological variants. One such variant, sebaceous EMCA (SEMCA), has been reported in the literature. Distinguishing it from other tumors such as sebaceous carcinoma is crucial, as SEMCA typically behaves more indolently. We present a case of a SEMCA in the right parotid of a 71-year-old man that shows features of aggressive behavior such as facial nerve invasion and extraparenchymal extension. Also, we report evidence of preexisting pleomorphic adenoma within this tumor.