Contrast-enhanced Ultrasound for Diagnosis of Renal Cystic Mass

Abstract

Background: Cystic Renal Cell Carcinoma (CRCC) is often difficult to differentiate from complex cysts with sonographic manifestations of renal carcinoma. Contrast-Enhanced Ultrasound (CEUS) is a new technology, and its clinical utility in the diagnosis of renal cystic mass has not been established.

Objective: The objective of this study is to analyze the characteristics of CEUS of renal cystic masses and to explore the clinical significance and value of CEUS in the diagnosis of CRCC.

Methods: This study was a retrospective study. A total of 32 cystic masses from January 2018 to December 2019 were selected. The images of conventional Ultrasound (US) and CEUS were confirmed via surgical pathology. Routine US was used to observe the location, shape, size, boundary, cyst wall, internal echo, and blood supply of each cystic mass. CEUS observed contrast enhancement of the cyst wall, cystic septa, and solid nodules of cystic masses.

Results: There were 26 cases of CRCC, 5 cases of renal cysts, and 1 case of renal tuberculosis. The enhancement pattern, degree of enhancement, and pseudocapsular sign by CEUS in benign and malignant masses had statistically significant differences (P<.05). In the diagnosis of CRCC, the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were 92.3%, 83.3%, 90.6%, 96.0%, and 71.4% for CEUS; 57.6%, 66.7%, 59.3%, 88.2%, and 26.7% for conventional US, respectively. CEUS had a higher sensitivity and accuracy than the conventional US (P<.05), although the diagnostic specificity, positive predictive value and negative predictive value of the two methods were not significantly different (P>.05).

Conclusion: CEUS is more accurate in the diagnosis of renal cystic masses, and it can be used as an effective imaging method.

Keywords: Contrast-enhanced ultrasound; MRI; conventional ultrasound; cystic masses; renal cell carcinoma; renal cystic masses.