A comparative study of contrast-enhanced ultrasound and contrast-enhanced CT for the detection and characterization of renal masses

This study aims to compare the value of contrast-enhanced ultrasound (CEUS) and contrast-enhanced CT (CECT) in the differential diagnosis of benign and malignant renal masses. Included in this retrospective study were 143 renal masses in 141 patients using histopathological findings as the gold standard. A comparison was made of the two modalities in image characteristics for their accuracy in the differential diagnosis of renal masses. CEUS and CECT were both used for 39 masses in 37 patients, with 31 (79.5%) being malignant and 8 (20.5%) benign. The differences between the benign and malignant groups in perfusion intensity, perfusion uniformity and entry and exit of the contrast agent were not statistically significant (P > 0.05). However, CEUS could better display the circular perfusion of renal cell carcinoma than CECT (P < 0.05). CECT alone detected 109 masses in 107 patients, with 93 (85.3%) being malignant and 16 (14.7%) benign. CEUS detected 73 masses in 71 patients, with 56 (76.7%) being malignant and 17 (23.3%) benign. No statistically significant differences were observed between CEUS and CECT in the diagnosis of renal cell carcinoma (92.8% vs. 90.3%), with a specificity of 52.9% vs. 31.2%, an accuracy of 83.5% vs. 81.6%, and a positive predictive value of 86.7% vs. 88.4% or a negative predictive value of 69.2% vs. 35.7% (P > 0.05 for all). These results suggested both CEUS and CECT are highly valuable in the differential diagnosis of renal masses, and CEUS can be used as an important supplement for CECT in diagnosis of renal cancer.