Acinic cell carcinoma of the parotid gland presenting as an external auditory canal mass.

BACKGROUND The fissures of Santorini have long been known as a gateway for disease to pass from the external auditory canal to the periparotid and neck spaces. Although anatomically understandable, description of disease that originates in the parotid gland and extends through the fissures to the external auditory canal is rare. This is, in fact,the first presentation of such a patient at our institution in a previously untreated patient. METHODS A 43-year-old woman was seen with a mass in her right external auditory canal. Further evaluation found this to be the presenting finding of a parotid neoplasm. The patient also had a right marginal mandibular paresis. Biopsy of the external auditory canal mass provided a diagnosis of an acinic cell adenocarcinoma. She underwent a right lateral temporal bone resection, type III modified neck dissection, and radical parotidectomy with facial nerve sacrifice and rectus abdominus reconstruction with facial nerve grafting. RESULTS Pathologic examination of the specimen revealed an acinic cell carcinoma of the right parotid gland with focal dedifferentiation into a high-grade adenocarcinoma. CONCLUSIONS Care should be taken with auditory canal masses to remember the possibility that disease is extending from the parotid through the fissures of Santorini, and evaluation and management should proceed accordingly.