Clear cell myoepithelial carcinoma ex pleomorphic adenoma of parotid gland: Case report and review of literature

Abstract Myoepithelial carcinoma (MC), also known as malignant myoepithelioma, shows an infiltrative and destructive growth [1]. Myoepithelial neoplasms account for about 1.5% of all salivary tumors, and MC is even more rare, representing about 10% of myoepitheliomas [1–3] with a reported incidence of 0.2% of all salivary gland tumors. In this case, the cytological diagnosis (pleomorphic adenoma) and negative lymph nodes, addressed the surgeon for a parotidectomy, following guidelines and literature [27]. The best treatment for huge, relapsing tumors, notwithstanding cytological diagnosis, is not only parotidectomy, as lymphadenectomy should be performed too, given myoepithelial carcinoma's high-grade potential and unpredictable biologic behavior. Careful patient follow-up and staging, is therefore essential for better characterization and understanding of this tumor's behavior in the future. We also considered a more conservative treatment following guidelines, as this case was lacking metastases and lymphatic involvement, considering that application of guidelines, surgical and clinical expertise and appropriate technology can contain potential medicolegal implications [28].