Malignant Oncocytoma of a Minor Salivary Gland: An Unusual Presentation at the Base of the Tongue

In contrast to malignant oncocytomas of the parotid gland, malignant oncocytomas arising from minor extraparotid glandular tissue are rare. The latter may display a locally aggressive behaviour as well as a variable tendency to develop secondary cervical lymph nodes. We report a new case of malignant oncocytoma in a 43-year-old man presenting with greatly enlarged cervical lymph nodes accompanied by a poorly defined swelling at the base of the tongue microscopically identified as a malignant oncocytoma. The diagnosis was strongly supported by the ultrastructural features of the cells almost completely filled with mitochondria. The cervical mass was excised, and the patient has suffered no recurrence for nearly 2 years after surgical treatment.