[The role of contrast-enhanced pulse inversion harmonic imaging (CEUS) and contrast-enhanced computed tomography (CECT) in the preoperative diagnosis of renal lesions]. / Die Rolle von kontrastmittelverstärktem "pulse inversion harmonic imaging" (CEUS) und kontrastmittelverstärkter Computertomographie (CECT) bei der präoperativen Diagnose von renalen Raumforderungen.

ABSTRACT

OBJECTIVE: The preoperative assessment of structural and functional changes in renal tumors using contrast-enhanced pulse inversion harmonic imaging (CEUS) and contrast-enhanced computed tomography (CECT). MATERIALS AND METHODS: All consecutive patients referred to two tertiary hospitals for surgery on suspicion of a malignant renal lesion, who had been examined under the predefined study protocol using CEUS and CECT, were prospectively included in the study. All renal lesions suspected of being malignant were subjected to histopathological examination. Lesions expected to be benign were followed up according to the study protocol. The accuracy of CEUS and CECT with the final histology or follow-up results and the statistically significant difference between the two imaging techniques was calculated. RESULTS: Over a period of 3 years (2008-2011), 68 of 93 patients examined met the study criteria. The prevalence of malignant tumors in the study was 72%. Fifty four (79%) patients underwent surgery and had a histologically confirmed renal tumor (clear cell carcinoma 45, urothelial papillocarcinoma 4, angiomyolipoma 1, oncytoma 3, xanthogranulomatous pyelonephritis 1) and 14 (21%) patients underwent regular follow-up. Specificity, sensitivity and area under the curve (AUC) reached 57.9%, 98% and 0.779 for CEUS and 52.6%, 98% and 0.753 for CECT. CONCLUSION: The results show that both imaging methods can reliably rule out malignant disease due to absence of enhancement. Taking into consideration that CEUS can be carried out without severe risk or discomfort, it is time to reconsider CEUS as the method of choice for diagnosis, while CECT should be reserved for staging.