Renal oncocytoma on 1-¹¹C acetate positron emission tomography: Case report and literature review

Renal oncocytomas are uncommon tumors of the renal collecting duct. Although generally benign, these tumors pose a diagnostic and therapeutic dilemma in that they can not be differentiated noninvasively from renal cell carcinomas. We report a 67-year-old man who underwent a clinical 1-¹¹C acetate positron emission tomography (PET) scan for evaluation of possible metastatic prostate carcinoma. The study demonstrated a nodule at the inferior pole of the right kidney with more uptake than the remainder of the kidney. Correlation was made with MRI, which demonstrated that the nodule was solid, and enhanced after contrast agent administration. Upon resection, this nodule was determined to be an oncocytoma. To our knowledge, this marks the first report of the 1-¹¹C acetate PET scan appearance of a renal oncocytoma Possible mechanisms for increased uptake include dysfunctional, but up-regulated oxidative phosphorylation or uptake through lipid biosynthesis pathways.