Evaluation of shearwave elastography for the characterisation of focal liver lesions on ultrasound

Objectives: To determine the elasticity characteristics of focal liver lesions (FLLs) by shearwave elastography (SWE). Methods: We used SWE in 108 patients with 161 FLLs and in the adjacent liver for quantitative and qualitative FLLs stiffness assessment. The Mann-Whitney test was used to assess the difference between the groups of lesions where a P value less than 0.05 was considered significant. Results: SWE acquisitions failed in 22 nodules (14 %) in 13 patients. For the 139 lesions successfully evaluated, SWE values were (in kPa), for the 3 focal fatty sparings (FFS) 6.6 ± 0.3, for the 10 adenomas 9.4 ± 4.3, for the 22 haemangiomas 13.8 ± -5.5, for the 16 focal nodular hyperplasias (FNHs) 33 ± -14.7, for the 2 scars 53.7 ± 4.7, for the 26 HCCs 14.86 ± 10, for the 53 metastasis 28.8 ± 16, and for the 7 cholangiocarcinomas 56.9 ± 25.6. FNHs had significant differences in stiffness compared with adenomas (P = 0.0002). Fifty percent of the FNHs had a radial pattern of elevated elasticity. A significant difference was also found between HCCs and cholangiocarcinomas elasticity (P = 0.0004). Conclusions: SWE could be useful in differentiating FNHs and adenomas, or HCCs and cholangiocarcinomas by ultrasound. Key Points: • Elastography is becoming quite widely used as an adjunct to conventional ultrasound • Shearwave elastography (SWE) could help differentiate adenomas from fibrous nodular hyperplasia • SWE could also be helpful in distinguishing between hepatocellular carcinomas and cholangiocarcinomas • SWE could improve the identify hepatocellular carcinomas in cirrhotic livers