Oncocytic lesion of parotid gland: A dilemma for cytopathologists

Abstract

Oncocytes are epithelial cells with abundant, granular, eosinophilic cytoplasm due to presence of numerous large mitochondria of varied sizes. The presence of oncocytes in salivary glands can occur in a variety of conditions. Here, we present a rare case of a 68 year old male patient who presented with a 6 cm diameter swelling in the right parotid region. A fine needle aspiration cytology done from the lesion showed a cellular oncocytic lesion. A possibility of oncocytoma was entertained. Histopathology of the mass showed a rare entity called diffuse hyperplastic oncocytosis. Originally believed to be a metaplastic process, oncocytes can occur in various lesions ranging from hyperplastic conditions to malignant neoplasms. However, diagnosis on cytological smears can be very challenging for the cytopathologist.

Oncocytoma Parotid Gland: A Case Report and Brief Review of Literature

“…4 Oncocytomas usually occur in the elderly and affect the parotid glands in 80%. 10 In our case, the FNAC was clearly suggestive of oncocytic features of the tumor and after histopathological examination oncocytoma was confi rmed. Pathogenesis is quite obscure, although mitochondrial functional defects are believed to mediate the progressive degeneration of the salivary epithelial cells.…”

A rare case of oncocytoma of the parotid gland with aggresssive features and malignant potential: a case report

“…Diagnosis by fine needle aspiration cytology (FNAC) may be very difficult and sensitivity in detection of oncocytic neoplasms is reported to be only 29%. 5,7,8 Even though FNAC has been used as a primary screening tool for salivary gland lesions with high levels of sensitivity and specificity, salivary glands do have the tendancy for having overlapping morphological features, therefore differentiating oncocytoma from oncocytic carcinoma can be difficult on cytology as the former can appear cytologically malignant looking, while the latter can look deceptively benign. Furthermore, differentiating oncocytosis from oncocytoma in cytology is difficult not to mention unattainable.…”

Extra-tongue oral granular cell tumor: Histological and immunohistochemical aspect

“…Oncocytic cells seen in endocrine and exocrine tissues such as salivary gland are epithelial cells characterized by an abundant eosinophilic and granular cytoplasm with a central pyknotic nucleus (26). The “swollen” appearance is due to the high amount of mitochondrias (27), which are altered in the salivary gland tumors.…”