The fifth version of the Clinical Practice Guidelines for Hepatocellular Carcinoma was revised by the Japan Society of Hepatology, according to the methodology of evidence‐based medicine and partly to the Grading of Recommendations Assessment, Development and Evaluation system, which was published in October 2021 in Japanese. In addition to surveillance–diagnostic and treatment algorithms, a new algorithm for systemic therapy has been created, as multiple drugs for hepatocellular carcinoma can be currently selected. Here, new or revised algorithms and evidence on which the recommendations are based are described.

Aldo-keto reductase family 1, member B10 (AKR1B10), a cancer-related oxidoreductase, is expressed in well-differentiated hepatocellular carcinomas (HCCs). However, AKR1B10 levels are minimal in normal liver tissues (NLs), similar to the 70-kilodalton heat shock protein (HSP70) and glypican-3. Moreover, the role of AKR1B10 in chronic hepatitis or cirrhosis, which are considered preneoplastic conditions for HCC, has not been fully elucidated. The aim of this study was to evaluate the expression of AKR1B10, HSP70, and glypican-3 in 61 HCC tissue samples compared to corresponding non-tumorous liver tissues (NTs), comprising 42 chronic hepatitis and 19 cirrhosis cases to clarify the significance of molecular changes at the preneoplastic stages of HCC. Immunohistochemical analysis demonstrated that the median expression levels of AKR1B10 were higher in HCCs than in NTs (p < 0.001) and higher in NTs than NLs (p < 0.001) with 54.8%, 2.1%, and 0.3% expression in HCCs, NTs, and NLs, respectively. HSP70 and glypican-3 were expressed in HCCs, but minimally in NTs and NLs with no significant difference between expression in NTs and NLs. Furthermore, a multivariate analysis identified an association between hepatic steatosis and AKR1B10 expression in NTs (p = 0.020). Of the three protein expressed in well-differentiated HCCs, only AKR1B10 was upregulated in preneoplastic conditions, and a steatosis-related factor might influence its expression.

The Intractable Hepato‐Biliary Disease Study Group of Japan, sponsored by the Ministry of Health, Labor and Wealth, proposed in 2018 that patients with cirrhosis and a Child‐Pugh score of 5–9 should be diagnosed as having acute‐on‐chronic liver failure (ACLF) when a deterioration of liver function (“serum bilirubin level of 5.0 mg/dl or more” and “prothrombin time value of 40% or less of the standardized values and/or international normalization rates of 1.5 or more”) caused by severe liver damage develops within 28 days after an acute insult, including alcohol abuse, bacterial infection, gastrointestinal bleeding, and the exacerbation of underlying liver diseases. Disease severity can be classified into 4 grades depending on the extent of the deterioration in organ functions, including liver, kidney, cerebral, blood coagulation, circulatory and respiratory functions. The Study Group has since performed an annual nationwide survey of patients with ACLF diagnosed according to the proposed diagnostic criteria as well as those with disease conditions related to ACLF. A total of 501 patients, including 183 patients diagnosed as having ACLF, seen between 2017 and 2019 were enrolled, and univariate and multivariate analyses revealed that the proposed diagnostic criteria were useful for identifying cirrhotic patients with an unfavorable outcome following an acute insult. Consequently, the Study Group determined that the proposed diagnostic criteria should be used in both clinical practice and clinical research as formal diagnostic criteria.

We aimed to clarify the association between a novel serum fibrosis marker, Wisteria floribunda agglutinin-positive Mac-2-binding protein (WFA⁺-M2BP), and hepatocellular carcinoma (HCC) development in 355 patients with chronic hepatitis C who achieved sustained virologic response (SVR) through interferon-based antiviral therapy. Pretreatment serum WFA⁺-M2BP levels were quantified and the hazard ratios (HRs) for HCC development were retrospectively analyzed by Cox proportional hazard analysis. During the median follow-up time of 2.9 years, 12 patients developed HCC. Multivariate analysis demonstrated that high serum WFA⁺-M2BP (≥2.80 cut off index (COI), HR = 15.20, p = 0.013) and high fibrosis-4 (FIB-4) index (≥3.7, HR = 5.62, p = 0.034) were independent risk factors for HCC development. The three- and five-year cumulative incidence of HCC in patients with low WFA⁺-M2BP were 0.4% and 0.4%, respectively, whereas those of patients with high WFA⁺-M2BP were 7.7% and 17.6%, respectively (p < 0.001). In addition, combination of serum WFA⁺-M2BP and FIB-4 indices successfully stratified the risk of HCC: the five-year cumulative incidences of HCC were 26.9%, 6.8%, and 0.0% in patients with both, either, and none of these risk factors, respectively (p < 0.001). In conclusion, pretreatment serum WFA⁺-M2BP level is a useful predictor for HCC development after achieving SVR.