Validation trial to diagnose liver tumors by LI-RADS criteria

Abstract

Background and Aims LI-RADS® was created to standardize the reporting and data collection of CT and MR imaging for hepatocellular carcinoma (HCC). Recently, LI-RADS was gained attention because LI-RADS are consistent with and integrated into the American Association for the Study of Liver Diseases (AASLD) 2018 hepatocellular carcinoma (HCC) clinical practice guidance. However, there are few reports that have been verified LI-RADS. We aimed to assess diagnose with LI-RADS from image findings and examine whether the diagnosis made is appropriate. Methods The number of cases was 159 nodules in 159 cases in 3 facilities. There were 81 cases (50.9%) of the high risk group (HBV carrier or cirrhosis case) in LI-RADS. In addition, we examined cases other than the high risk group in LI-RADS in this study. We categorized into US-1 (Negative), US-2 (Subthreshold), US-3 (Positive) with ultrasound (US) LI-RADS. Furthermore, we analyzed cases diagnosed as malignant tumors by CT/MRI but no malignant findings (LR-4 or 5) in US LI-RADS. Conversely, the proportion of cases with benign tumors diagnosed as malignant in US LI-RADS was calculated. Results There were no cases equivalent to US-1 in this study. There were 4 cases of US-2, of which 2 non-malignant tumors, 1 hepatocellular carcinoma (highly differentiated) and 1 metastatic liver tumor were included. Both hepatocellular carcinoma and metastatic liver tumor were LR-3 on the basis of CT/MRI, and the diagnosis was different from that of US diagnosis (1.3%). Conversely, two non-malignant tumors were CT/MRI findings of LR-5 (1.3%), malignant tumors could not be denied and one case had hepatectomy. The cases of US-3 were 121 cases of hepatocellular carcinoma, 19 cases of intrahepatic bile duct cancer, 2 cases of mixed type liver cancer, 10 cases of metastatic liver tumor, and 3 cases of other malignant tumors. 10 cases of hepatocellular carcinoma (6.3%) and 4 cases of metastatic liver tumors (2.5%) were judged as LR-3 by CT/MRI, and diagnosis was different between US and CT/MRI. Conclusion Except for a few cases, US LI - RADS generally performed adequate diagnosis. Further upgrading to contrast enhanced US LI-RADS which corresponds to perflubutane will further improve diagnostic accuracy.