Diagnostic accuracy of contrast-enhanced ultrasound in differentiating benign and malignant focal liver lesions: A retrospective study

Purpose: The purpose of this study was to assess the diagnostic accuracy of our early experience with contrast-enhanced ultrasound (CEUS) in the characterisation of focal liver lesions (FLLs) using histopathology, contrast-enhanced computed tomography (CT), magnetic resonance imaging (MRI) or other imaging follow-up as the standard of reference. Materials and Methods: Seventy-three patients with 82 FLLs who underwent liver CEUS from January 2006 to December 2008 were retrospectively reviewed. CEUS was performed with up to 4.8 mL of SonoVue® (Bracco, Milan, Italy) using a low mechanical index mode. The CEUS findings were compared with histopathology, or where histopathology was not available, clinical and imaging follow-up over at least 12 months was used as the standard of reference. Results: Of the 82 FLLs, 50 were malignant and 32 were benign at final diagnosis. CEUS correctly identified 43 malignant FLLs, with final diagnosis confirmed by histopathology in 13 lesions and clinico-radiological follow-up in 30 lesions. Twenty-nine lesions were correctly identified as benign on CEUS, with all these lesions confirmed on clinico-radiological follow-up. CEUS demonstrated a sensitivity of 86.0% and a specificity of 90.6% in the characterisation of liver lesions as malignant, with an overall accuracy of 87.8% (P