Manca Garbajs1, Peter Popovic. 1. Clinical Institute of Radiology, University Medical Centre, Ljubljana, Slovenia.
Abstract
PURPOSE: The purpose of this study was to evaluate the efficacy of contrast-enhanced ultrasound (CEUS) in the assessment of therapeutic response, after percutaneous radiofrequency ablation (RFA) of small renal tumors. METHODS: Twenty patients (12 men, 8 women; median age, 77.4 years; median tumor size, 2.7 cm) were treated with RFA. All patients were examined by contrast-enhanced computed tomography (CECT), followed by CEUS one week later. Tumor enhancement characteristics and thickness of the enhancing area in viable lesions were evaluated. RESULTS: Median time from RFA to diagnostic imaging was 16.8 months. All 20 patients underwent CT. CEUS was finally performed in only 14 out of 20 patients (70%), since 2 out of 6 had contraindications for the application of a US contrast agent. Also, one patient refused the application and a further 3 had tumors that were impossible to differentiate adequately on the conventional B-mode US, in order to satisfactorily monitor the contrast enhancement. CEUS showed a complete response in 9 out of 14 (64.3%) patients, residual tumor in 4 (28.6%) and tumor progression in 1 patient (7.1%). Median thickness of the enhancing area on CECT and CEUS was 20 mm vs 17 mm, respectively, with no statistically significant difference in the thickness (t =-0.816, p=0.461) between both modalities. The concordance between CECT and CEUS in the assessment of tumor response and detection of residual vascular enhancement was 100%. CONCLUSIONS: CEUS is an effective and safe imaging modality in assessing the therapeutic response, after percutaneous radiofrequency ablation of small renal tumors. Disadvantages can be overcome with improved CEUS technology.
PURPOSE: The purpose of this study was to evaluate the efficacy of contrast-enhanced ultrasound (CEUS) in the assessment of therapeutic response, after percutaneous radiofrequency ablation (RFA) of small renal tumors. METHODS: Twenty patients (12 men, 8 women; median age, 77.4 years; median tumor size, 2.7 cm) were treated with RFA. All patients were examined by contrast-enhanced computed tomography (CECT), followed by CEUS one week later. Tumor enhancement characteristics and thickness of the enhancing area in viable lesions were evaluated. RESULTS: Median time from RFA to diagnostic imaging was 16.8 months. All 20 patients underwent CT. CEUS was finally performed in only 14 out of 20 patients (70%), since 2 out of 6 had contraindications for the application of a US contrast agent. Also, one patient refused the application and a further 3 had tumors that were impossible to differentiate adequately on the conventional B-mode US, in order to satisfactorily monitor the contrast enhancement. CEUS showed a complete response in 9 out of 14 (64.3%) patients, residual tumor in 4 (28.6%) and tumor progression in 1 patient (7.1%). Median thickness of the enhancing area on CECT and CEUS was 20 mm vs 17 mm, respectively, with no statistically significant difference in the thickness (t =-0.816, p=0.461) between both modalities. The concordance between CECT and CEUS in the assessment of tumor response and detection of residual vascular enhancement was 100%. CONCLUSIONS: CEUS is an effective and safe imaging modality in assessing the therapeutic response, after percutaneous radiofrequency ablation of small renal tumors. Disadvantages can be overcome with improved CEUS technology.
Authors: Akbar N Ashrafi; Nima Nassiri; Inderbir S Gill; Mittul Gulati; Daniel Park; Andre L de Castro Abreu Journal: Curr Urol Rep Date: 2018-08-28 Impact factor: 2.862