[Bilateral renal oncocytoma]

Renal oncocytoma, a benign tumour, is made up exclusively of oncocytes. These are large epithelial cells with granular eosinophilic cytoplasm extremely rich in mitochondria. Oncocytomas are very often mistaken for renal carcinomas, but due to their characteristic histological and ultrastructural features they are now diagnosed more frequently. We report a case of an unusual bilateral renal oncocytoma and describe briefly its clinical, radiological and pathological features.