A rare case of low-grade mucoepidermoid carcinoma of the retromolar trigone

Mucoepidermoid carcinoma is a malignant salivary gland tumor that very rarely involves the retromolar trigone. We report the case of a 31-year-old woman who referred to the emergency department of our university hospital with a 12-month history of a slow-growing parapharyngeal mass and recent onset of dyspnea in the supine position and dysphagia for solids. CT showed a hyperdense formation of about 4 x 2.5 cm involving the right mandibular region up to the palatine tonsil and the superior constrictor muscle of the right pharynx, with obliteration of the right portion of the nasopharynx and oropharynx. Based on clinical evaluation and radiological evidence, the patient underwent surgical excision of the mass, performing a right radical tonsillectomy extended to the ipsilateral retromolar area, with unerupted right third molar extraction. In this case, we describe a rare condition in a rare localization with unusual symptoms and should be always considered in the differential diagnosis with other similar conditions. However, the prompt diagnosis and treatment allowed a conservative surgical management of the case with good long-term prognosis.