Multimodality evaluation of bilateral parotid oncocytomas: A rare case report and literature review

Abstract

Oncocytoma of the parotid gland is a rare benign salivary gland neoplasm, accounting for less than 2% of all salivary tumors. Bilateral parotid oncocytoma is an exceedingly rare entity that can mimic other salivary gland neoplasms on imaging. We report the case of a 72-year-old woman who underwent 18F-fluorodeoxyglucose positron emission tomography–computed tomography (FDG PET-CT) for evaluation of unexplained weight loss and altered bowel habits. Imaging revealed incidentally detected, well-defined, FDG-avid masses within the deep lobes of both parotid glands. A CT-guided core needle biopsy was performed and immunohistochemistry confirmed the diagnosis of oncocytoma. This case highlights the diagnostic challenge posed by bilateral parotid oncocytomas due to their rarity and imaging overlap with other salivary gland tumors. A multimodality imaging approach, combined with histopathological confirmation, is essential for accurate diagnosis and appropriate management.