A case report of synchronous bilateral multifocal nodular oncocytic hyperplasia in parotid gland

Multifocal nodular oncocytic hyperplasia (MNOH), alternatively known as Benign Nodular Oncocytosis, was first identified by Schwartz and Feldman in Cancer in 1969. It manifests as numerous nodular growths of oncocytic cells scattered within the salivary gland tissue; Bilateral and multifocal lesions in the parotid gland are rare occurrences. Among these, bilateral multifocal oncocytic lesions are even less common. We report a case of 59-year-old woman with no prior medical or surgical history who presented to our ENT department due to a gradual, painless enlargement of both parotid glands that had been ongoing for four months. She underwent bilateral parotidectomy. Histologic exam confirmed the diagnosis of bilateral multifocal nodular oncocytic hyperplasia with a histological variant of clear cells. The postoperative course was unremarkable. Diagnosis presents challenges due to the rarity of this condition. Precise diagnosis relies on imaging techniques such CT scans and MRI features. There is no consensus on the therapeutic management. Our case report adds to the scarce literature concerning this condition, emphasizing the importance of careful clinical evaluation, precise diagnosis, and proper management.