Differentiation of Small, Solid Renal Masses: A Pattern Recognition Approach.

The incidence of small renal masses (SRMs) has shown significant increase owing to more widespread use of cross-sectional imaging. These SRMs include various subtypes of renal cell carcinomas (RCCs) and several types of benign tumors including angiomyolipomas. Differentiation between RCC and benign SRMs is crucial for a patient to receive optimal management. Therefore, it is important for the radiologist to recognize imaging patterns that are characteristic of or diffferentiate between RCCs and benign SRMs, when confronting a SRM. This article describes several well-known imaging patterns of SRMs reported in the literature.