Oncocytic mucoepidermoid carcinoma of the parotid gland.

Abstract

Oncocytic mucoepidermoid carcinoma of the salivary gland is rare. We describe a 60-year-old woman who presented with a slowly growing left parotid mass. The patient underwent a total parotidectomy, and her postoperative course was uneventful. The gland was enlarged and showed a partially cystic mass containing clear mucoid material. Microscopically, the entire mass showed variably sized cysts lined predominantly with oncocytes and a few mucous goblet cells. Histochemical stains for mitochondria, such as phosphotungstic acid-hematoxylin, confirmed the presence of oncocytes. The recognition of this variant is important, since most of the other primary oncocytic lesions of the salivary glands are benign. The tumor in this case is considered to be a low-grade carcinoma; therefore, complete surgical excision and long-term clinical follow-up are adequate management.