Computed Tomography of Renal Masses in Adults.

Renal masses are a common incidental finding in abdominal imaging. They typically are benign cysts but sometimes are kidney cancers-most frequently renal cell carcinoma (RCC) in adults. Alongside noncontrast computed tomography images, multiphase contrast-enhanced computed tomography (CECT) supports rapid, accurate differentiation of renal cysts from potential kidney cancers and can help with lesion characterization, staging, and surgical planning. CECT also can help physicians assess RCC histology or tumor subtype. This article discusses the biology, genetics, diagnostic imaging, classification, and staging of renal masses, with an emphasis on CECT kidney imaging, renal cysts, and RCC.