Voluminous Incidental Oncocytic Neoplasm of the Adrenal Gland With Uncertain Malignant Potential.

A 74-year-old man presented with right flank pain and a palpable mass in the left flank. Blood pressure was normal. Contrastenhanced computed tomography (CT) showed a 17 × 16 × 12 cm retroperitoneal mass over the left kidney, solid and heterogeneous. There were also 3 retro aortic lymph nodes and bilateral renal lithiasis. Twenty four-hour urinary metanephrines and normetanephrines were normal. The patient underwent a resection of the mass with left adrenalectomy by a lumbar incision. Histological findings revealed an adrenal oncocytic neoplasm (AON) with uncertain malignant potential. Six months after surgery, CT control showed neither local nor distant recurrence.