[Diffuse hyperplastic oncocytosis of the parotid gland]

An intracellular metabolic disturbance associated with mitochondriopathy, due to an age dependent metabolic defect, is suggested to cause metaplasia of salivary gland cells into oncocytes. The WHO classification of salivary gland diseases considers 3 oncocytic lesions: oncocytosis, oncocytoma and oncocytic carcinoma. In case of diffuse hyperplastic oncocytosis of the parotid gland, extensive metaplasia of acinic and ductal cells leads to transformation of nearly all cells of the gland into oncocytes, which is clinically characterised by swelling of the parotid gland, and is an extremely rare condition. A 82-year-old man (the eldest of all reported) presented with a 2-month history of increasing diffuse swelling of the left parotid gland, 6 cm in diameter. The mass was soft, painless to palpation and grew in the superficial lobe of the parotid gland. The patient underwent surgical removal of the lesion with wide margins of healthy tissue. Histopathological examination of the operative specimen disclosed oncocytosis of the salivary gland. The patient has been followed-up for 6 months. He is doing well without recurrence. Surgical removal of the diffuse hyperplastic oncocytosis of the parotid gland, with indications and extent of the resection like in benign tumors, was effective in the presented patient.