Bilateral renal oncocytoma: case report and implications in renal tumour management

Renal oncocytomas are uncommon benign tumours that have recently been recognized as a unique pathological entity. These lesions may attain considerable size; however, most present as an asymptomatic incidental finding. Although usually solitary, these tumours are occasionally multicentric or bilateral at presentation. Retrospective studies suggest that oncocytoma may account for up to 5% of tumours previously classified as well-differentiated renal cell carcinoma. At present, conservative management is hampered by difficulty in establishing a confident pre-operative or intra-operative diagnosis. A case of bilateral asymptomatic renal oncocytoma is presented, and the implications of this lesion for the management of renal tumours is discussed.