External Auditory Canal Pleomorphic Adenoma: A Rare Case Presentation

Pleomorphic adenoma originating from the external auditory canal is extremely rare, benign tumor. Ceruminal glands are modified sweat glands of the skin, present in the external auditory canal that may give rise to (a) benign tumors such as ceruminous adenoma, pleomorphic adenoma, and syringocystadenoma papilliferum, or (b) malignant tumors such as ceruminous adenocarcinoma, adenoid cystic carcinoma, and mucoepidermoid carcinoma. We report a case where a 25-year-old woman presented with right aural swelling and otalgia since 1 year. A canal-filling aural mass was noted on clinical examination. Computed tomography imaging showed no intracranial extension or any association with the adjacent parotid gland. Subsequent excision biopsy and histologic examination revealed features suggestive of pleomorphic adenoma. Similar to the pleomorphic adenoma of salivary glands, recurrence or malignant degeneration with cellular atypia and metastasis can occur on rare occasions. Care must be taken to distinguish this from adenoid cystic carcinomas, ceruminous adenocarcinomas, and mucoepidermoid carcinomas.