99mTc-Sestamibi SPECT/CT Evaluation of Renal Oncocytomas

Abstract We present 2 cases of the benign renal neoplasm, oncocytoma, evaluated with 99m Tc-sestamibi single-photon emission computed tomography/computed tomography (SPECT/CT) imaging. Oncocytoma is a benign, solid enhancing renal mass that resembles the much more common renal cell carcinoma on standard imaging studies. Differentiation can be difficult due to shared imaging and histological characteristics; therefore, diagnosis historically primarily relied on resection. However, in a subset of patients who are poor candidates for surgical excision or percutaneous biopsy, a possible option for planning follow-up management is 99m Tc-sestamibi SPECT/CT imaging. These cases highlight the role of 99m Tc-sestamibi SPECT/CT imaging in differentiating benign oncocytomas from malignant renal cell carcinomas.