Parotid gland myoepithelioma with remarkable cystic formation: A case report

Myoepithelioma is a rare tumor, accounting for less than 1.5% of all salivary gland tumors. Generally, this tumor exhibits painless solid mass. We here report an extremely rare case of myoepithelioma with remarkable cystic formation in the parotid gland in an 80-year-old female. In this case, a malignant tumor with cystic formation of the parotid gland was clinically suspected following preoperative imaging examinations. Standard superficial parotidectomy was thus performed under general anesthesia. Histopathologic findings revealed that the tumor consisted of spindle cells, plasmacytoid cells, and epithelioid cells, and remarkable cystic formation was observed. Immunohistochemically, the neoplastic cells were positive for S-100, cytokeratin, vimentin, and calponin. The final histopathologic diagnosis was myoepithelioma. Four years have past after the surgery without recurrence of the tumor.