The Liver Imaging Reporting and Data System (LI-RADS) is a comprehensive system for standardizing the terminology, technique, interpretation, reporting, and data collection of liver imaging. LI-RADS was created specifically for patients at risk for hepatocellular carcinoma by experts in liver imaging and supported by the American College of Radiology in the context of surveillance by ultrasonography (US); diagnosis by computed tomography (CT) or magnetic resonance imaging (MRI), or contrast material-enhanced US; and assessment of treatment response by CT or MRI. Additionally, the Li-RADS diagnostic algorithm is integrated into the latest guidelines of the American Association for the Study of Liver Diseases. This article provides 1) a broad overview of LI-RADS v2018, including its relationships to other imaging guidelines, composition, and aims; and 2) detailed description, issues, and future directions of CT/MRI diagnostic LI-RADS.

The United States is currently the leading country for the standardization of the diagnostic imaging reporting system on hepatic tumors. The US/CEUS Liver Imaging Reporting and Date System (LI-RADS), which is an ultrasound diagnostic system along with CT and MRI, is a diagnostic algorithm for hepatocellular carcinoma (HCC) proposed by the American College of Radiology (ACR), and it is also recommended by the American Institute of Ultrasound in Medicine (AIUM) and the American Association for the Study of Liver Diseases (AASLD). The reporting system in our country will be based on the US/CEUS LI-RADS in the near future. In this article, the US/CEUS LI-RADS and the Japanese version of Clinical Practice Guidelines for Hepatocellular Carcinoma including Sonazoid^® will be reviewed.

A 79-year-old male patient with hypertension, hyperlipidemia, and chronic alcoholic liver disease was referred to our hospital because an abdominal ultrasound had revealed multiple tumors in the liver.

Abdominal ultrasound revealed hypoechoic masses measuring 30 mm in diameter at S8 and 15 mm in diameter at S6. On contrast-enhanced computed tomography, both these tumors had a high density in the arterial phase, with the S8 tumor showing gradual washout from the portal phase and the S6 tumor showing a delay in the contrast effect up to the equilibrium phase. We performed a subsection of the liver S8 tumor and partial resection of the S6 tumor at our hospital. On histopathological examination, the S8 tumor was diagnosed as mid-differentiated hepatocellular carcinoma and the S6 tumor as cholangiocellular carcinoma. The combination of cholangiocellular carcinoma and hepatocellular carcinoma described in this case report is a rare finding worthy of documentation.

An 85-year-old woman underwent repeated transcatheter arterial chemoembolization (TACE) and stereotactic body radiation therapy (SBRT) for hepatocellular carcinoma (HCC) with cirrhosis C. She was treated with Daclatasvir/Asunaprevir for 24 weeks for HCV. HCV-RNA became negative at the end of administration, but relapsed 16 weeks later. After that, she was treated with Glecaprevir/Pibrentasvir. At the start of the administration, it was confirmed that it was Child-Pugh A and no HCC was observed on the image. On the 28^th day after the beginning of the administration, she developed jaundice and hepatic dysfunction, and she was hospitalized. However, she developed acute on chronic hepatic failure and hepatorenal syndrome and died on the 13^th day of hospitalization. Autopsy findings showed extensive liver fibrosis, tumor necrosis, and residual cancer cells. Even with compensated cirrhosis, if damage to the background liver is expected, such as having multiple HCC treatments, serious side effects should be taken into consideration when treating.

A woman in her 60s who had been diagnosed with chronic hepatitis B visited our hospital regularly. Abdominal contrast-enhanced computed tomography revealed a space-occupying lesion (SOL) with a size of 3 cm on the spleen, which was under observation. Six months later, a follow-up abdominal contrast-enhanced MRI showed new SOLs in liver S4 and S6. The splenic SOL did not increase in size. Both hepatic SOLs were concentrated in the arterial phase and washed out in the equilibrium phase, suggesting hepatocellular carcinoma, and hepatectomy was performed. Follicular lymphoma was diagnosed through a pathological evaluation of the surgical specimen, and FDG-PET showed an accumulation in the liver, spleen, and systemic lymph nodes, classified as Ann Arbor stage IV. After six courses of chemotherapy, she is still alive and without recurrence. We report a rare case of hepatic follicular lymphoma, whose imaging findings are suggestive of hepatocellular carcinoma.

A 38-year-old woman developed nausea and fatigue the day after eating a large amount of macadamia nuts. She was diagnosed with acute hepatitis at a nearby facility. After hospitalization, her liver function worsened. She tested negative for various viral markers and autoantibodies, and no organic abnormality was found on imaging. She was transferred to our hospital, where steroid pulse therapy was initiated. Due to the significantly increased prothrombin time and loss of consciousness, she was diagnosed with subacute fulminant hepatitis. Plasma exchange and continuous slow hemodiafiltration were performed, and the liver function normalized after six plasma exchange sessions. A liver biopsy was performed after her condition improved, and the pathology revealed nonspecific hepatitis. The result of a macadamia nut DLST was strongly positive. She continued to progress uneventfully after discontinuation of the treatment and was discharged on the 46^th day of hospitalization. We report a very rare case of fulminant hepatitis resulting from food poisoning.