Oncocytoma of the parotid gland: Dilemma for the cytopathologist

Abstract

Oncocytoma is a rare benign tumor of the salivary glands usually seen in elderly patients in the sixth to eighth decade. Microscopically, the hallmark of this lesion is the presence of oncocytes that comprise the entire tumor. These are large polygonal cells which have abundant eosinophilic granular cytoplasm, and from central to eccentric round nucleus. Several reactive as well as neoplastic lesions of salivary glands often have concurrent oncocytic changes. On fine-needle aspiration cytology, all of them have overlapping morphological features, thus making the diagnosis difficult by cytology alone. We report a case of oncocytoma of the right parotid gland in a 32-year-old Indian male. Although the tumor was initially suspected on cytology, confirmation was possible only after histopathological examination. The main purpose of this case report is to discuss the cytological differential diagnosis of oncocytic lesions of salivary glands and simultaneously emphasize the importance of histopathology for arriving at conclusive diagnosis in such cases.

Keywords

• Oncocytic cells, oncocytoma, parotid gland, salivary gland