Oncocytoma: A Mystifying Parotid Gland Tumour

Abstract

Oncocytoma is a rare salivary gland tumor consisting of oncocytes with many hyperplastic mitochondria. It usually occurs in the parotid gland. Very few cases of parotid oncocytoma have been reported in literature. Because of its rarity (<1-2% of salivary gland tumors) and clinical presentation of the tumor. Clinical diagnosis is often challenging due to the likeness of oncocytoma to other benign and low-grade malignant salivary gland tumors there is a tendency among the clinicians to misdiagnose it as pleomorphic adenoma, hemangioma, or other forms of oncocytosis. Previously published articles had all agreed on the reality of this lesion occurring over the parotid gland. The paper aims to review previously published cases of oncoytoma to provide a better insight regarding demographic, clinicopathological, radiological and histological features of this rare tumor of parotid gland. A systemic review of English literature was performed after using a sensitive search strategy involving two different databases: google scholar and PubMed. A total number of 9 cases were included. The tumour is mostly presented in old age as a slowly growing tumour (mean duration 3.17 years) and showed a  slightly higher female predominance (Female:Male=1.25:1). They were mostly located over superficial lobe,100%. Conventional histological variant has only been reported. Complete surgical excision was performed for all the cases without any reports of recurrence or malignant transformation. Imaging studies diagnosed the lesion as a benign tumor. Only histopathological examination can confirm it. Definitive histology examination concludes to oncocytoma. Furthermore, our aim is to bring to the forefront how these lesions require a comprehensive workup and how to choose the best treatment strategy.

Mugda Med Coll J. 2023; 6(1): 30-36