Imaging of Renal Tumors

Renal tumors are increasing in incidence, at least partly on the basis of incidental detection during the routine use of abdominal imaging for non-genitourinary indications. Conventional imaging with anatomic modalities such as computed tomography, magnetic resonance imaging, and ultrasound constitute not only the most common method by which renal tumors are identified but also form the backbone for characterizing certain aspects of renal masses. Characterization with conventional imaging generally focuses on determining the solid or cystic nature of a mass, defining the size of the mass, local tumor staging, and evaluation for the presence of metastases. For many renal masses, conventional imaging fails to provide accurate assessment of the tumor’s histologic type, and for this reason molecular imaging techniques are being actively investigated as means to noninvasively risk-stratify patients and appropriately triage those patients who harbor benign or indolent renal masses to active surveillance. In this chapter, we will summarize modern anatomic and molecular methods of imaging renal tumors.