Conventional imaging studies such as ultrasound, computed tomography, and magnetic resonance imaging are increasingly detecting small renal masses, which are interpreted by radiologists as highly suspicious for renal cell cancer. However, up to 30% of these small solid tumors (<4 cm) are in fact found to be benign on surgical excision. This highlights a significant limitation in conventional radiologic imaging studies in sub-stratifying which patient require active treatment (i.e. surgery versus thermal ablation) versus surveillance. It also highlights a tremendous opportunity for investigations into how advanced imaging technologies could play a role in radically changing the current paradigm in the management of small renal tumors. New imaging technologies such as advanced cross-sectional imaging, molecular imaging and optical imaging show promise in improving pre-treatment risk categorization with the hopes of reducing unnecessary treatment. Together radiologists, urologists, and computer imaging experts amongst others have the opportunity to discover, develop and test new diagnostic imaging modalities to improve patient care.

Learning objectives:

1. Recognize the relatively high incidence of benign tumors found following renal tumor surgery for small renal masses.

2. Identify the limitations of conventional cross-sectional imaging in characterizing small renal masses.

3. Describe how new advanced imaging modalities may in the future help predict tumor phenotype and thus reduce the number of unnecessary treatments of benign or low risk renal tumors.