Differentiating Renal Neoplasms From Simple Cysts on Contrast-Enhanced CT on the Basis of Attenuation and Homogeneity

Abstract

Homogeneous simple renal cysts can have mean attenuation values of up to 30 HU, as determined by contrast-enhanced CT, whereas homogeneous RCCs have mean attenuation values as low as 42 HU, with no overlap occurring between the two groups. These data suggest that further evaluation of a homogeneous renal mass with a mean attenuation value of 30 HU or less on a contrast-enhanced CT scan likely is unwarranted.