Focal nodular hyperplasia and hepatocellular adenoma: The value of shear wave elastography for differential diagnosis

Objective: This study assessed the clinical usefulness of shear wave elastography (SWE) during ultrasound for differentiating between focal nodular hyperplasias (FNHs) and hepatocellular adenomas (HAs). Materials and methods: SWE was performed on 56 patients presenting with 76 liver lesions (57 FNHs and 19HA5) that were confirmed by MRI and contrast-enhanced ultrasound (CEUS) (n = 55) or by histology (n = 21).A mean elasticity value was obtained for each lesion. The ratios of the elasticity of the lesions to the elasticity of the surrounding liver were determined. The optimal elasticity cut-off value for distinguishing between the two lesion types was determined using ROC analysis. All lesions that were classified as "undetermined" after CEUS were reclassified using the elasticity values. Results: The mean elasticity value was 46.99 +/- 31.15 kPa for FNHs and 12.08 +/- 10.68 kPa for HAs (p < 0.0001). The mean relative elasticity ratio values were 7.94 +/- 6.43 and 1.91 +/- 1.70, respectively (p <0.0001). The ROC analysis showed a maximal accuracy of 95% for identification with a cut-off of 18.8 kPa for lesion elasticity (accuracy of 96% with a cut-off of 1.98 for the relative elasticity ratio). A total of 68CEUS were performed, and 17 lesions (25%) were classified as "undetermined" after CEUS. With these cut-off values 16 lesions (94.1%) were correctly reclassified as FNHs. Conclusion: SWE is a useful adjunctive tool for differentiation between FNH and HA during ultrasound examination. (C) 2015 Elsevier Ireland Ltd. All rights reserved.