99mTc-MIBI SPECT/CT Evaluation of a Renal Collision Tumor

Abstract

Preoperative differentiation of oncocytomas from renal cell carcinoma (RCC) is often challenging. ^99mTc-MIBI imaging could play a potential role in differentiating oncocytoma from RCC, which in turn could guide surgical decision-making. We present the use of ^99mTc-MIBI SPECT/CT to characterize a renal mass in a 66-year-old man with a complex medical history, including history of bilateral oncocytomas. ^99mTc-MIBI SPECT/CT showed features suspicious of a malignant tumor, which was confirmed postnephrectomy as a chromophobe and papillary RCC collision tumor. This case supports ^99mTc-MIBI imaging for preoperative differentiation of benign versus malignant renal tumors.