In Japan and Western countries, according to the guidelines for managing hepatocellular carcinoma, radical treatments, such as liver resection or radiofrequency ablation, are recommended for tumors within the Milan criteria (single tumors of ≤ 5 cm in size or three nodules of ≤ 3 cm in size). In Western countries, liver transplantation is a recommended treatment. However, there is a wide heterogeneity in the malignant potential of hepatocellular carcinoma even within the Milan criteria. Therefore, allocating appropriate treatments according to their malignant potential is desirable. Some risk factors for malignant potential could be estimated using pathological examinations only, but other risk factors could be predicted by examining clinical characteristics using imaging modalities. In this review, the methods for estimating the malignant potential of hepatocellular carcinoma were organized, and the differences in treatment strategies for hepatocellular carcinoma within the Milan criteria between Japan and Western countries were also evaluated.

Hepatitis virus tests are commonly performed, particularly for preoperative assessment. Although with a limited effect, alert systems in electronic medical records are a measure to promote the referral of hepatitis virus carriers to hepatology specialists. Additionally, our hospital has been conducting study sessions for nonspecialized clinical departments and individual recommendations through interprofessional collaboration, including clinical laboratory technicians. The response rate to patients positive for hepatitis virus in each nonspecialized clinical department increased after the study sessions. Furthermore, it increased dramatically to 92.1% after individual recommendations through interprofessional collaboration. Of all patients with internal referrals to hepatologists through recommending consultation, 20 patients with hepatitis B started nucleotide analogs, and 32 patients with hepatitis C started direct-acting antiviral (DAA) therapy. Moreover, the rate of internal referrals increased as a consultation opportunity for cases treated with DAAs. Study sessions in each clinical department and individual recommendations through interprofessional collaboration are useful for recommending intrahospital consultations.

An 81-year-old male with unresectable hepatocellular carcinoma (HCC) was treated with lenvatinib after split drug-eluting bead transarterial chemoembolization (DEB-TACE). He was referred to our department for the further examination of AST and ALT elevations. A 15-cm-diameter internal heterogeneous HCC occupied the left lobe of the liver. The tumor was unresectable and we initially performed split DEB-TACE to reduce the amount of tumor and to avoid adverse events including tumor lysis syndrome and postembolization syndrome. He was treated with DEB-TACE without any trouble except temporary elevations of both AST and ALT. After a series of DEB-TACE, CT images showed that residual HCC remained viable at the periphery of the tumor, and lenvatinib treatment was initiated. Three months after the initiation of lenvatinib treatment, a complete response was achieved, and serum AFP and PIVKA-2 levels declined to normal. Since then, CR has been maintained by continuing lenvatinib.

A 64-year-old man in whom benign hyperbilirubinemia had been identified was found to suffer from acute hepatitis E. Laboratory examination of the patient revealed high transaminase levels and hyperbilirubinemia, suggesting acute hepatitis, while the prothrombin time was within the normal range. The transaminase levels decreased and prothrombin time remained within the normal range; however, hyperbilirubinemia worsened to 39 mg/dl. The patient developed the complications of acute renal failure and sepsis, and eventually died. An autopsy was performed that showed no liver atrophy, liver fibrosis progression, or massive necrosis. The lung and kidney were revealed to be positive for fungal infection. The kidney was revealed to exhibit tubular congestion with bile. The present case offers information on the clinical course of acute hepatitis E in relatively elderly patients.

An 18-year-old man was admitted to our hospital due to sudden melena. Abdominal computed tomography showed splenomegaly, developed collateral vein, and gastroesophageal varices. Emergency upper endoscopy showed red plaque on gastric cardial varices without active bleeding. The injection of 67% NBCA (n-butyl-2-cyanoacrylate: Histacryl^®) was performed in the vicinity of the red plaque. Finally, we diagnosed the case as congenital porto-systemic shunt (CPS) by intravenous balloon occluded portography, abdominal angiography, and liver biopsy. The patient was discharged after two sessions of endoscopic injection therapy to the esophageal varices. To our knowledge, this is the first report of CPS diagnosed with ruptured gastric varices.

An 8-year-old boy was admitted to our hospital because of anorexia, jaundice, and liver dysfunction. Based on liver biopsy, the patient was initially diagnosed with noninfectious acute hepatitis. Treatment with prednisolone (PSL) improved hepatobiliary enzyme levels. The patient was readmitted due to liver dysfunction, which recurred following PSL dose tapering. Although the re-administration of PSL was partly effective, cyclosporine and azathioprine had to be added because the liver function data did not improve sufficiently. Finally, liver biopsy revealed noncaseous epithelioid granulomas in the portal tracts. On the histopathological findings, serum angiotensin-converting enzyme and soluble interleukin-2 receptor levels were elevated; thus, the patient was diagnosed with hepatic sarcoidosis. Combined steroid pulse therapy and azathioprine markedly improved liver function data and histological findings. Case reports of hepatic sarcoidosis in children are rare, but this disease should not be overlooked as a possible cause of acute liver dysfunction based on immunological abnormalities.

A 42-year-old man was admitted to our hospital with a complaint of right abdominal pain. Based on imaging examinations, the patient was diagnosed with liver cirrhosis and an 8-mm tumor in the anterior segment of the liver 2 years ago. On contrast-enhanced computed tomography, high arterial-phase contrast uptake and rapid wash-out during the late phase were observed. Based on these findings, we performed partial hepatectomy and cholecystectomy with a preoperative diagnosis of hepatocellular carcinoma. The pathological diagnosis of the lesion conforms to the 2019 World Health Organization classification of intraductal papillary neoplasm of the bile duct. Preoperative diagnosis was difficult because the localization of the tumor was in the periphery of the liver, and the imaging findings were atypical.

An 82-year-old male underwent extended left hepatectomy for hepatocellular carcinoma (HCC) 3 years ago. Then, the patient was performed transarterial chemoembolization for multiple intrahepatic recurrences 2 years ago, and percutaneous radiofrequency ablation for another solitary recurrence a year ago. In October 2019, the patient was diagnosed with right ventricular metastasis without inferior vena cava or right atrial invasion. Four and eight weeks after the administration of lenvatinib, the right ventricular tumor appeared to shrink and was evaluated as stable disease according to the Response Evaluation Criteria in Solid Tumors, version 1.1. Lenvatinib was continued for 12 months and changed to regorafenib because of proteinuria and the gradually enlarging right ventricular tumor. The patient is still alive 14 months after the diagnosis of cardiac metastasis. Here we report a rare case of isolated cardiac metastasis of HCC treated with lenvatinib.

Diagnostic imaging of a primary hepatic neuroendocrine tumor (NET) is often difficult as this pathology is usually diagnosed by performing a liver tumor biopsy. Imaging of this tumor has been reported as a non-uniform hyperechoic mass on abdominal ultrasonography (US), low absorption on plain abdominal computed tomography (CT), only edge enhancement on enhanced CT, a low signal on T1-weighted magnetic resonance imaging (MRI), and a high signal on T2-weighted MRI. We report two cases of NET that presented as low echoic masses on abdominal US and as non-uniform masses on CT examination.

In developing guidelines, clinical questions (CQs) are developed, followed by a comprehensive literature search, and then, articles are selected according to clear selection criteria. In the process, the first screening is based on the title and abstract, while the second screening is based on the full text. We have developed a system for all processes of article selection deployed in a cloud storage system, which can be accessed by multiple users simultaneously. This system is equipped with management functions of reviewers, CQs, bibliographic data, and full-text documents and could monitor real-time progress and resolve discrepancies among reviewers' selection on the system, which can significantly reduce the effort required for the paper selection process.