Background: Mucoepidermoid carcinoma ex-pleomorphic adenoma (MECxPA) is an extremely rare salivary gland malignancy. With only nine prior reported cases, this entity represents a challenging histopathological diagnosis. Methods: We present a case of a 71-year-old male with an enlarging left neck mass over several months. CT showed both a parapharyngeal space mass and a separate level II neck mass. Results: The patient underwent resection of the left parapharyngeal mass and ipsilateral selective level II-IV lymphadenectomy. The final pathologic diagnosis was metastatic high-grade mucoepidermoid carcinoma ex-pleomorphic adenoma. Conclusions: We describe a novel presentation of high-grade mucoepidermoid carcinoma ex-pleomorphic adenoma as a metastatic parapharyngeal mass.
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