The role of contrast-enhanced ultrasound in the classification of CT-indeterminate renal lesions

AbstractObjective: Focal renal lesions are common incidental findings on computed tomography (CT). For lesions with a cystic appearance, the Bosniak classification system has enabled an important separation of benign and (potentially) malignant cysts, giving a practical guide for management. The purpose of this study was to evaluate contrast-enhanced ultrasound (CEUS) as a problem-solving modality for classification of indeterminate renal lesions detected with CT.Materials and methods: In total, 140 consecutive patients with 148 indeterminate renal lesions were examined with ultrasound combined with CEUS (81 men and 59 women with mean age 63.8 years).Results: Altogether, 146 lesions were classified by CEUS in categories according to the Bosniak classification system, or as solid lesions. Mean lesion diameter was 30 mm (range 5–166 mm). Nine lesions were classified as category I, 32 as category II and 59 as category IIF (“non-surgical lesions”). 48 IIF cysts were followed for a minimum of 2 years (mean 4 y...