Giant renal oncocytoma: a case report and review of the literature

Abstract

Abstract Introduction Renal oncocytomas are benign neoplasms derived from cells of the distal renal tubule, and comprise 5% to 7% of primary renal neoplasms. Oncocytomas are mostly asymptomatic, and the majority of tumors are discovered incidentally. In this case report, we present a case of a patient with a giant oncocytoma arising from her left kidney. Case presentation We describe a 25-year-old Turkish woman who was admitted to our hospital with abdominal pain and a 3-year palpable abdominal mass, which was found present since her second pregnancy. Examination revealed a 15 × 20-cm mass in her abdominal cavity. Computed tomography revealed a mass with regular outlines, measuring 18 × 11 × 12 cm, associated with the left kidney, and causing marked hydroureteronephrosis. We excised the mass and performed a left nephrectomy on our patient. The immunohistopathology of the mass was consistent with renal oncocytoma. No local or distant metastasis was seen at 6 months postoperatively. Conclusion To the best of our knowledge, this is the second largest renal oncocytoma described in the English language literature. This is also the first reported giant oncocytoma that presented during pregnancy.