Assessment of renal cell carcinoma after cryoablation using contrast-enhanced gray-scale ultrasound

We performed contrast-enhanced gray-scale harmonic ultrasound (CUS) in three patients with renal cell carcinoma after cryoablation. CUS showed the decreased enhancement similar to the findings of CT or MRI. It identified feeding vessels more distinctly and found a larger number compared with CT or MRI. A persistent feeder in one case was related to recurrence. CUS may potentially be an alternative to CT and MRI and a useful method in the prediction of recurrent and residual tumors.