Hepatocellular carcinoma with steatohepatitic features: a clinicopathological study of Japanese patients

Sonic hedgehog expression in steatohepatitic hepatocellular carcinoma and its clinicopathological significance

Hedgehog (Hh) signaling pathway dysregulation is involved in the pathogenesis of metabolic dysfunction-associated steatohepatitis, and the sonic Hh (SHh) protein, a pivotal molecule in the Hh pathway, is expressed in ballooned hepatocytes. The present study aimed to investigate the clinicopathological significance of SHh expression in steatohepatitic hepatocellular carcinoma (SH-HCC). Reverse transcription-quantitative polymerase chain reaction and immunohistochemistry were performed to examine SHh gene and SHh protein expression in SH-HCC. Additionally, patients with conventional HCC (C-HCC) were included in the control group. Comparisons of patient and tumor characteristics were also performed. The prevalence of SH-HCC was 3% in the whole cohort, and it was significantly associated with a high prevalence of diabetes mellitus. SHh mRNA was detected in all patients with SH-HCC, but not in 23% of patients with C-HCC. Notably, SHh mRNA expression was not significantly different between patients with SH-HCC and those with C-HCC; however, high SHh protein expression was significantly more frequent in SH-HCC patients than in those with C-HCC. Although the prognosis was not significantly different between the SH-HCC and C-HCC groups, high SHh protein expression was an independent poor prognostic factor for HCC. In conclusion, SHh could potentially serve as a therapeutic target for patients with HCC.

Steatohepatitic hepatocellular Carcinoma:A new approach to classifying morphological subtypes of hepatocellular carcinoma

Histological subtyping of hepatocellular carcinoma (HCC) is challenging in the presence of histological heterogeneity, where distinctly different morphological patterns are present within the same tumor. Current approaches rely on percent cut-offs. We hypothesized that morphologic intratumor heterogeneity is a non-random biological feature and that incorporating recurrent patterns would improve histological subtyping of HCC. Resected HCC were studied and the overall frequency of morphologic intratumor heterogeneity was 45% in 242 specimens. Steatohepatitic HCC (SH-HCC) had the highest frequency of morphologic intratumor heterogeneity (91%); this was confirmed in additional cohorts of SH-HCC from different medical centers (overall frequency of 78% in SH-HCC). Morphologic intratumor heterogeneity in SH-HCC showed distinct and recurrent patterns that could be classified as early, intermediate, and advanced. Incorporating these patterns into the definition of SH-HCC allowed successful resolution of several persistent challenges: the problem of the best cut-off for subtyping SH-HCC, the problem of the relationship between SH-HCC and scirrhous HCC, and the classification for HCC with abundant microvesicular steatosis. This approach also clarified the relationship between SH-HCC and CTNNB1 mutations, showing that CTNNB1 mutations occur late in a subset of SH-HCC. In summary, there is a high frequency of morphologic intratumor heterogeneity in HCC. Incorporating this finding into histological subtyping resolved several persistent problems with the SH-HCC subtype.

Emerging Roles of Spatial Transcriptomics in Liver Research

Spatial transcriptomics, leveraging sequencing- and imaging-based techniques, has emerged as a groundbreaking technology for mapping gene expression within the complex architectures of tissues. This approach provides an in-depth understanding of cellular and molecular dynamics across various states of healthy and diseased livers. Through the integration of sophisticated bioinformatics strategies, it enables detailed exploration of cellular heterogeneity, transitions in cell states, and intricate cell-cell interactions with remarkable precision. In liver research, spatial transcriptomics has been particularly revelatory, identifying distinct zonated functions of hepatocytes that are crucial for understanding the metabolic and detoxification processes of the liver. Moreover, this technology has unveiled new insights into the pathogenesis of liver diseases, such as the role of lipid-associated macrophages in steatosis and endothelial cell signals in liver regeneration and repair. In the domain of liver cancer, spatial transcriptomics has proven instrumental in delineating intratumor heterogeneity, identifying supportive microenvironmental niches and revealing the complex interplay between tumor cells and the immune system as well as susceptibility to immune checkpoint inhibitors. In conclusion, spatial transcriptomics represents a significant advance in hepatology, promising to enhance our understanding and treatment of liver diseases.

Imaging and prognostic characterization of fat-containing hepatocellular carcinoma subtypes

PURPOSE

Steatohepatitic hepatocellular carcinoma (SH-HCC) is characterized by intratumoral fat with > 50% inflammatory changes. However, intratumoral fat (with or without inflammation) can also be found in not-otherwise specified HCC (NOS-HCC). We compared the imaging features and outcome of resected HCC containing fat on pathology including SH-HCC (> 50% steatohepatitic component), NOS-HCC with < 50% steatohepatitic component (SH-NOS-HCC), and fatty NOS-HCC (no steatohepatitic component).

MATERIAL AND METHODS

From September 2012 to June 2021, 94 patients underwent hepatic resection for fat-containing HCC on pathology. Imaging features and categories were assessed using LIRADS v2018. Fat quantification was performed on chemical-shift MRI. Recurrence-free and overall survival were estimated.

RESULTS

Twenty-one patients (26%) had nonalcoholic steatohepatitis (NASH). The median intra-tumoral fat fraction was 8%, with differences between SH-HCC and SH-NOS-HCC (9.5% vs. 5% p = 0.03). There was no difference in major LI-RADS features between all groups; most tumors were classified as LR-4/5. A mosaic architecture on MRI was rare (7%) in SH-HCC, a fat in mass on CT was more frequently depicted (48%) in SH-HCC. A combination of NASH with no mosaic architecture on MRI or NASH with fat in mass on CT yielded excellent specificity for diagnosing SH-HCC (97.6% and 97.7%, respectively). The median recurrence-free and overall survival were 58 and 87 months, with no difference between groups (p = 0.18 and p = 0.69).

CONCLUSION

In patients with NASH, an SH-HCC may be suspected in L4/LR-5 observations with no mosaic architecture at MRI or with fat in mass on CT. Oncological outcomes appear similar between fat-containing HCC subtypes.

Fat-containing hepatocellular carcinoma in patients with cirrhosis: proposal of a diagnostic modification regarding enhancement characteristics

OBJECTIVES

The aim of this study was to develop and validate an algorithm for the non-invasive diagnosis of these fat-containing HCCs.

METHODS

Eighty-four cirrhotic patients with 77 fat-containing HCCs and 11 non-HCC fat-containing nodules were retrospectively included. All MRIs were reviewed; nodule characteristics, European Association for the Study of the Liver (EASL) and LI-RADS classifications, and survival were collected. One of the major features of LI-RADS v2018 (non-rim-like arterial phase hyperenhancement [APHE]) was changed to include different enhancing patterns at arterial phase and a new fat-LI-RADS algorithm was created for fat-containing nodules in cirrhosis. Its diagnostic performance was evaluated in both a derivation and external validation cohort (external cohort including 58 fat-containing HCCs and 10 non-HCC fat nodules). Reproducibility of this new algorithm was assessed.

RESULTS

In the derivation cohort, 54/77 (70.1%) fat-containing HCCs had APHE, 62/77 (80.5%) had enhancement compared to the nodule itself at arterial phase (APE), 43/77 (55.8%) had washout, and 20/77 (26.0%) had an enhancing capsule. EASL and LI-RADS had a sensitivity of 37.7% (29/77) and 36.4% (28/77), respectively, for the diagnosis of fat-containing HCC and both had a specificity of 100% (11/11). The new fat-LI-RADS algorithm increased sensitivity to 50.6% (39/77) without decreasing the specificity of 100% (11/11). The validation cohort confirmed the increased sensitivity, with a slight decrease in specificity. The concordance for the diagnosis of HCC for fat-LR5 was 85.3% (58/68).

CONCLUSION

The new fat-LI-RADS algorithm proposed here significantly improves the performance of the non-invasive diagnosis of fat-containing HCC and thus could reduce the number of biopsies conducted for fat-containing HCCs.

CLINICAL RELEVANCE STATEMENT

The European Association for the Study of the Liver and LI-RADS guidelines are poorly sensitive for the diagnosis of fat-containing HCC, mainly because of the low rate of arterial phase hyperenhancement (APHE) displayed by fat-containing HCC. Using all types of enhancement instead of APHE improves sensitivity of LI-RADS.

KEY POINTS

• Fat-containing HCCs on MRI account for 7.5% of HCCs and have different imaging characteristics from non-fatty HCCs. • The European Association for the Study of the Liver and LI-RADS algorithms for the non-invasive diagnosis of HCC have low sensitivity for the diagnosis of fat-containing HCC with MRI (37.7% and 36.4%, respectively). • The new fat-LI-RADS, which includes a slight modification of the "arterial enhancement" criterion, improves the sensitivity for the diagnosis of fat-containing HCC using MRI, without degrading the specificity.

SOCS5-RBMX stimulates SREBP1-mediated lipogenesis to promote metastasis in steatotic HCC with HBV-related cirrhosis

Abnormal lipid metabolism promotes hepatocellular carcinoma (HCC) progression, which engenders therapeutic difficulties owing to unclear mechanisms of the phenomenon. We precisely described a special steatotic HCC subtype with HBV-related cirrhosis and probed its drivers. Hematoxylin-eosin (HE) staining of 245 HCC samples revealed a special HCC subtype (41 cases) characterized by HBV-related cirrhosis and intratumoral steatosis without fatty liver background, defined as steatotic HCC with HBV-related cirrhosis (SBC-HCC). SBC-HCC exhibits a larger tumor volume and worse prognosis than non-SBC-HCC. Screening for driver genes promoting fatty acid (FA) biosynthesis in the Gao's HBV-related cirrhosis HCC cases and GSE121248' HBV-related HCC cases revealed that high expression of SOCS5 predicts increased FA synthesis and that SOCS5 is upregulated in SBC-HCC. Through proteomics, metabolomics, and both in vivo and in vitro experiments, we demonstrated that SOCS5 induces lipid accumulation to promote HCC metastasis. Mechanistically, through co-IP and GST-pulldown experiments, we found that the SOCS5-SH2 domain, especially the amino acids Y413 and D443, act as critical binding sites for the RBMX-RRM domain. SOCS5-RBMX costimulates the promoter of SREBP1, inducing de novo lipogenesis, while mutations in the SH2 domain, Y413, and D443 reverse this effect. These findings precisely identified SBC-HCC as a special steatotic HCC subtype and highlighted a new mechanism by which SOCS5 promotes SBC-HCC metastasis.

Pathological overview of steatohepatitic hepatocellular carcinoma in a surgical series

AIMS

According to the last WHO classification, steatohepatitic hepatocellular carcinoma (SH-HCC) is recognized as a distinct HCC subtype, even though a consensual definition is still lacking. The objectives of the study were to carefully describe the morphological features of SH-HCC and evaluate its impact on prognosis.

METHODS AND RESULTS

We conducted a single-centre retrospective study including 297 surgically resected HCC. Pathological features including SH criteria (steatosis, ballooning, Mallory-Denk bodies, fibrosis, and inflammation) were assessed. SH-HCC was defined by the presence of at least four of the five SH criteria and the SH component represented >50% of the tumour area. According to this definition, 39 (13%) HCC cases corresponded to SH-HCC and 30 cases (10%) corresponded to HCC with an SH component (<50%). SH criteria in SH-HCC and non-SH-HCC were distributed as follows: ballooning (100% versus 11%), fibrosis (100% versus 81%), inflammation (100% versus 67%), steatosis (92% versus 8%), and Mallory-Denk bodies (74% versus 3%). Inflammation markers (c-reactive protein [CRP] and serum amyloid A [SAA]) were significantly more expressed in SH-HCC compared to non-SH-HCC (82% versus 14%, P = <0.001). Five-year recurrence-free survival (RFS) and 5-year overall survival (OS) were similar for SH-HCC and non-SH-HCC (P = 0.413 and P = 0.866, respectively). The percentage of SH component does not impact OS and RFS.

CONCLUSION

We confirm in a large cohort the relatively high prevalence (13%) of SH-HCC. Ballooning is the most specific criteria for this subtype. The percentage of the SH component does not impact prognosis.

Clinico-histological and molecular features of hepatocellular carcinoma from nonalcoholic fatty liver disease

Patients with nonalcoholic fatty liver disease (NAFLD) continue to increase with the epidemics of obesity, and NAFLD is estimated to become the most prevalent etiology of hepatocellular carcinoma (HCC). Recently, NAFLD-HCC has been recognized to have clinico-histologically and molecularly distinct features from those from other etiologies, including a lower incidence rate of HCC and less therapeutic efficacy to immune checkpoint inhibitors (ICIs). Consistent with the clinical observations that up to 50% of NAFLD-HCC occurs in the absence of cirrhosis, the imbalance of pro- and antitumorigenic hepatic stellate cells termed as myHSC and cyHSC can contribute to the creation of an HCC-prone hepatic environment, independent of the absolute fibrosis abundance. Immune deregulations by accumulated metabolites in NAFLD-affected livers, such as a fatty-acid-induced loss of cytotoxic CD4 T cells serving for immune surveillance and "auto-aggressive" CXCR6+ CD8 T cells, may promote hepatocarcinogenesis and diminish therapeutic response to ICIs. Steatohepatitic HCC (SH-HCC), characterized by the presence of fat accumulation in tumor cells, ballooned tumor cells, Mallory-Denk body, interstitial fibrosis, and intratumor immune cell infiltration, may represent a metabolic reprogramming for adapting to a lipid-rich tumor microenvironment by downregulating CPT2 and leveraging its intermediates as an "oncometabolite." Genome-wide analyses suggested that SH-HCC may be more responsive to ICIs given its mutual exclusiveness with β-catenin mutation/activation that promotes immune evasion. Thus, further understanding of NAFLD-specific hepatocarcinogenesis and HCC would enable us to improve the current daily practice and eventually the prognoses of patients with NAFLD.

Advances in Histological and Molecular Classification of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a primary liver cancer characterized by hepatocellular differentiation. HCC is molecularly heterogeneous with a wide spectrum of histopathology. The prognosis of patients with HCC is generally poor, especially in those with advanced stages. HCC remains a diagnostic challenge for pathologists because of its morphological and phenotypic diversity. However, recent advances have enhanced our understanding of the molecular genetics and histological subtypes of HCC. Accurate diagnosis of HCC is important for patient management and prognosis. This review provides an update on HCC pathology, focusing on molecular genetics, histological subtypes, and diagnostic approaches.

Radiologic features of hepatocellular carcinoma related to prognosis

The cross-sectional imaging findings play a crucial role in the diagnosis of hepatocellular carcinoma (HCC). Recent studies have shown that imaging findings of HCC are not only relevant for the diagnosis of HCC, but also for identifying genetic and pathologic characteristics and determining prognosis. Imaging findings such as rim arterial phase hyperenhancement, arterial phase peritumoral hyperenhancement, hepatobiliary phase peritumoral hypointensity, non-smooth tumor margin, low apparent diffusion coefficient, and the LR-M category of the Liver Imaging-Reporting and Data System have been reported to be associated with poor prognosis. In contrast, imaging findings such as enhancing capsule appearance, hepatobiliary phase hyperintensity, and fat in mass have been reported to be associated with a favorable prognosis. Most of these imaging findings were examined in retrospective, single-center studies that were not adequately validated. However, the imaging findings can be applied for deciding the treatment strategy for HCC, if their significance can be confirmed by a large multicenter study. In this literature, we would like to review imaging findings related to the prognosis of HCC as well as their associated clinicopathological characteristics.

MRI features associated with HCC histologic subtypes: a western American and European bicenter study

OBJECTIVES

To evaluate if preoperative MRI can predict the most frequent HCC subtypes in North American and European patients treated with surgical resection.

METHODS

A total of 119 HCCs in 97 patients were included in the North American group and 191 HCCs in 176 patients were included in the European group. Lesion subtyping was based on morphologic features and immuno-histopathological analysis. Two radiologists reviewed preoperative MRI and evaluated the presence of imaging features including LI-RADS major and ancillary features to identify clinical, biologic, and imaging features associated with the main HCC subtypes.

RESULTS

Sixty-four percent of HCCs were conventional. The most frequent subtypes were macrotrabecular-massive (MTM-15%) and steatohepatitic (13%). Necrosis (OR = 3.32; 95% CI: 1.39, 7.89; p = .0064) and observation size (OR = 1.011; 95% CI: 1.0022, 1.019; p = .014) were independent predictors of MTM-HCC. Fat in mass (OR = 15.07; 95% CI: 6.57, 34.57; p < .0001), tumor size (OR = 0.97; 95% CI: 0.96, 0.99; p = .0037), and absence of chronic HCV infection (OR = 0.24; 95% CI: 0.084, 0.67; p = .0068) were independent predictors of steatohepatitic HCC. Independent predictors of conventional HCCs were viral C hepatitis (OR = 3.20; 95% CI: 1.62, 6.34; p = .0008), absence of fat (OR = 0.25; 95% CI: 0.12, 0.52; p = .0002), absence of tumor in vein (OR = 0.34; 95% CI: 0.13, 0.84; p = .020), and higher tumor-to-liver ADC ratio (OR = 1.96; 95% CI: 1.14, 3.35; p = .014) CONCLUSION: MRI is useful in predicting the most frequent HCC subtypes even in cohorts with different distributions of liver disease etiologies and tumor subtypes which might have future treatment and management implications.

KEY POINTS

• Representation of both liver disease etiologies and HCC subtypes differed between the North American and European cohorts of patients. • Retrospective two-center study showed that liver MRI is useful in predicting the most frequent HCC subtypes.

Clinicopathological assessment of steatohepatitic hepatocellular carcinoma

AIM

To compare the clinicopathological features of typical steatohepatitic HCC (SH-HCC) with other HCCs.

METHODS

Subjects were 486 patients with untreated HCC who underwent hepatectomy at our hospital from January 2015 to December 2020. We compared patient backgrounds, preoperative laboratory data, imaging findings (ultrasonography, computed tomography [CT], and magnetic resonance imaging [MRI]), and postoperative pathological findings (tumor and background of liver). The Liver Imaging Reporting And Data System (LI-RADS) was used to examine CT and MRI findings.

RESULTS

Typical SH-HCCs were significantly different from other HCCs with respect to age, hepatitis B virus (HBV) infection, and nonalcoholic steatohepatitis (NASH). Diabetes and hyperlipidemia were also significantly more common. Regarding histopathology, tumor size and background steatosis were significantly different between groups. Although ultrasonography, CT, and MRI could each alone diagnose SH-HCCs with a diameter < 20 mm in ≥ 50% of patients, the combined use of these tests improved diagnostic accuracy. By LI-RADS, 87% of SH-HCC cases were classified as LR-5, which are considered to be malignant tumors.

CONCLUSIONS

It seems possible to diagnose SH-HCC by combining ultrasonography, CT, and MRI.

MRI features of histologic subtypes of hepatocellular carcinoma: correlation with histologic, genetic, and molecular biologic classification

HCC is a heterogeneous group of tumors in terms of histology, genetic aberration, and protein expression. Advancements in imaging techniques have allowed imaging diagnosis to become a critical part of managing HCC in the clinical setting, even without pathologic diagnosis. With the identification of many HCC subtypes, there is increasing correlative evidence between imaging phenotypes and histologic, molecular, and genetic characteristics of various HCC subtypes. In this review, current knowledge of histologic heterogeneity of HCC correlated to features on gadolinium-enhanced dynamic liver MRI will be discussed. In addition, HCC subtype classification according to transcriptomic profiles will be outlined with descriptions of histologic, genetic, and molecular characteristics of some relatively well-established morphologic subtypes, namely the low proliferation class (steatohepatitic HCC and CTNNB1-mutated HCC) and the high proliferation class (macrotrabecular-massive HCC (MTM-HCC), scirrhous HCC, and CK19-positive HCC). Characteristics of sarcomatoid HCC and fibrolamellar HCC will also be discussed. Further research on radiological characteristics of HCC subtypes may ultimately enable non-invasive diagnosis and serve as a biomarker in predicting prognosis, molecular characteristics, and therapeutic response. In the era of precision medicine, a multidisciplinary effort to develop an integrated radiologic and clinical diagnostic system of various HCC subtypes is necessary. KEY POINTS: • HCC is a heterogeneous group of tumors in terms of histology, genetic aberration, and protein expression, which can be divided into many subtypes according to transcriptome profiles. • There is increasing evidence of a correlation between imaging phenotypes and histologic, genetic, and molecular biologic characteristics of various HCC subtypes. • Imaging characteristics may ultimately enable non-invasive diagnosis and subtype characterization, serving as a biomarker for predicting prognosis, molecular characteristics, and therapeutic response.

Decreased ARG1 expression as an adverse prognostic phenotype in non-alcoholic non-virus-related hepatocellular carcinoma

The incidence of non-alcoholic non-virus-related hepatocellular carcinoma (NANV-HCC) is increasing along with the growing prevalence of metabolic disorders. In this subset, few useful biomarkers are available to narrow down the high-risk group for recurrence. This study aimed to evaluate the prognostic impact of decreased ARG1 (arginase-1), which is pathologically known as a marker reflecting hepatocyte differentiation, in NANV-HCC. Besides, its relationship with biliary/progenitor cell markers, whose expressions are associated with poor prognosis, was also assessed. To reveal the clinicopathological association of decreased ARG1 expression in NANV-HCC, we investigated 99 patients who underwent curative-intent hepatectomy for NANV-HCC. Tissue microarrays were employed for immunohistochemical analysis. A total of 21 NANV-HCC cases (21%; 21/99) showed decreased ARG1 expression. Decreased ARG1 expression was an independent prognostic factor for both poor DFS (hazard ratio 2.17; 95% confidence interval 1.15-4.09; p = 0.02) and OS (hazard ratio 4.09; 95% confidence interval 1.71-9.80; p = 0.002). In addition, decreased ARG1 expression was significantly associated with expressions of biliary/progenitor cell markers, CK19 and CD56 (p < 0.01). As cytologic features of tumor cells, decreased ARG1 expression was significantly associated with lipid-less cytologic morphology (p = 0.045). These findings indicate that decreased ARG1 expression is a predictive phenotype of postoperative recurrence with poor prognosis in patients with NANV-HCC. Decreased ARG1 expression may be a precursor or overlapping feature with biliary/progenitor cell marker expressions in NANV-HCC.

Variant Hepatocellular Carcinoma Subtypes According to the 2019 WHO Classification: An Imaging-Focused Review

The 2019 5th edition of the WHO Classification of Digestive System Tumors estimates that up to 35% of hepatocellular carcinomas (HCCs) can be classified as one of eight subtypes defined by molecular characteristics: steatohepatitic, clear cell, macrotrabecular massive, scirrhous, chromophobe, fibrolamellar, neutrophil-rich, and lymphocyte-rich HCC. Due to their distinct cellular and architectural characteristics, these subtypes may not display the classic MRI features of HCC of arterial phase hyperenhancement (APHE) and washout appearance, creating challenges in noninvasively diagnosing such lesions as HCC. Moreover, certain subtypes with atypical imaging features have a worse prognosis than other HCCs. A range of distinguishing imaging features may help raise suspicion that a liver lesion represents one of these HCC subtypes. In this review, we describe the MRI features that have been reported in association with various HCC subtypes according to the 2019 WHO classification, with attention to current understanding of these subtypes' pathologic and molecular bases and relevance to clinical practice. Imaging findings that differentiate the subtypes from benign liver lesions and non-HCC malignancies are highlighted. Familiarity with these subtypes and their imaging features may allow the radiologist to suggest their presence, though histologic analysis remains needed to establish the diagnosis.

Nonalcoholic non-virus-related hepatocellular carcinoma arising from nonsteatotic liver: Clinical and pathological features

Nonalcoholic non-virus-related hepatocellular carcinoma (NANV-HCC) is considered to occur in steatotic livers; however, emerging evidence indicates that a subset of NANV-HCC occurs in nonsteatotic livers. Currently, little information is available regarding this subset. This study sought to provide the clinical and pathological features of NANV-HCC in nonsteatotic livers.We retrospectively investigated the clinicopathological features of 101 consecutive patients with NANV-HCC treated with a curative-intent hepatectomy. A background liver with <5% steatosis by area was regarded as a nonsteatotic liver. Survivals of patient subgroups were estimated using the Kaplan-Meier method, and log-rank tests were conducted to assess the survival difference. Multivariate analysis was performed with the Cox proportional hazards method.Overall, 34 of 101 patients with NANV-HCC were found to have a nonsteatotic liver. Vascular invasion of the tumor was more frequently observed in patients with a nonsteatotic liver than in those with a steatotic liver (P = .03). The extent of lobular inflammation and fibrosis did not differ between patients with and without steatosis in the liver. NANV-HCC with a nonsteatotic liver was independently associated with a shorter disease-free survival (DFS) (hazard ratio [HR] 2.14; 95% confidence interval [CI] 1.21-3.80; P = .009) and a shorter overall survival (OS) (HR 2.79; 95% CI 1.27-6.16; P = .01) than NANV-HCC with a steatotic liver.The absence of steatosis in the liver is independently associated with shorter DFS and OS in patients with NANV-HCC. Our findings indicate that nonsteatotic liver can be a surrogate phenotype of aggressive NANV-HCC.

Distinctive features of hepatocellular carcinoma in non-alcoholic fatty liver disease

Hepatocellular carcinoma (HCC) is on the rise globally, causing more than 800 thousand deaths annually, with an estimated annual percent change of 0.51 for causes other than viral hepatitis, including nonalcoholic fatty liver disease (NAFLD). The incidence of NAFLD-related HCC is peaking in several Far East regions (6-12% vs. 2-3% in Western Europe and USA), HCC risk being mainly driven by the epidemic of obesity and diabetes, both favored by an unhealthy diet and sedentary lifestyle. Under inherited susceptibility outlined by such genetic markers as variants in PNPLA3, TM6SF2 and MBOAT7, neoplastic transformation of NAFLD is driven by sublethal lipotoxicity consequent to hepatocyte lipid overload, whereas a myriad of factors spanning from subverted circadian homeostasis and gut dysbiosis to alcohol abuse and tobacco may interact as risk modifiers. At variance with viral HCC, NAFLD-HCC shows a frequent association with cardiovascular co-morbidities, absence of cirrhosis in up to half of patients and an association with persistently normal transaminase values. All these misleading features of NAFLD-related HCC account for the low uptake of surveillance and linkage to curative treatments that has been reported in patients with this cancer, a downside that could be attenuated when scores for cost-effective risk stratification become available.

Imaging features of histological subtypes of hepatocellular carcinoma: Implication for LI-RADS

Background & Aims

The histopathological subtypes of hepatocellular carcinoma (HCC) are associated with distinct clinical features and prognoses. This study aims to report Liver Imaging Reporting and Data System (LI-RADS)-defined imaging features of different HCC subtypes in a cohort of resected tumours and to assess the influence of HCC subtypes on computed tomography (CT)/magnetic resonance imaging (MRI) LI-RADS categorisation in the subgroup of high-risk patients.

Methods

This retrospective institutional review board-approved study included patients with resected HCCs and available histopathological classification. Three radiologists independently reviewed preoperative CT and MRI exams. The readers evaluated the presence of imaging features according to LI-RADS v2018 definitions and provided a LI-RADS category in patients at high risk of HCC. Differences in LI-RADS features and categorisations were assessed for not otherwise specified (NOS-HCC), steatohepatitic (SH-HCC), and macrotrabecular-massive (MTM-HCC) types of HCCs.

Results

Two hundred and seventy-seven patients (median age 64.0 years, 215 [77.6%] men) were analysed, which involved 295 HCCs. There were 197 (66.7%) NOS-HCCs, 62 (21.0%) SH-HCCs, 23 (7.8%) MTM-HCCs, and 13 (4.5%) other rare subtypes. The following features were more frequent in MTM-HCC: elevated α-foetoprotein serum levels (p <0.001), tumour-in-vein (p <0.001 on CT, p ≤0.052 on MRI), presence of at least 1 LR-M feature (p ≤0.010 on CT), infiltrative appearance (p ≤0.032 on CT), necrosis or severe ischaemia (p ≤0.038 on CT), and larger size (p ≤0.006 on CT, p ≤0.011 on MRI). SH-HCC was associated with fat in mass (p <0.001 on CT, p ≤0.002 on MRI). The distribution of the LI-RADS major features and categories in high-risk patients did not significantly differ among the 3 main HCC subtypes.

Conclusions

The distribution of LI-RADS major features and categories is not different among the HCC subtypes. Nevertheless, careful analysis of tumour-in-vein, LR-M, and ancillary features as well as clinico-biological data can provide information for the non-invasive diagnosis of HCC subtypes.

Lay summary

In high-risk patients, the overall distribution of LI-RADS major features and categories is not different among the histological subtypes of hepatocellular carcinoma, but tumour-in-vein, presence of LR-M features, and ancillary features can provide information for the non-invasive diagnosis of hepatocellular carcinoma subtypes.

•

The distribution of the major features and categories of LI-RADS is not different among the HCC histological subtypes.

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MTM-HCC was associated with TIV, ≥1 LR-M feature, infiltrative appearance, necrosis or severe ischaemia, and larger size.

•

Steatohepatitis-related HCC was associated with fat in mass on CT and on MRI.

Steatotic and Steatohepatitic Hepatocellular Carcinomas: Features in a Series With Predominantly Viral Etiology

Hepatocellular carcinomas (HCCs) with steatohepatitis and steatosis are reported with varying definitions and clinicopathologic features. We aimed to search the attributes of steatohepatitic hepatocellular carcinoma (SH-HCC) and steatotic-HCC in our series. A retrospective clinicopathologic analyses of 150 HCCs and immunostaining for C-reactive protein (CRP) and serum amyloid A (SAA) were performed. Tumors were reclassified as all SH-HCC, limited SH-HCC, typical SH-HCC (steatohepatitic features in >5%, 5% to 50%, and ≥50% of the tumor, respectively), steatotic-HCC, and classic HCC (C-HCC). Group comparisons were made using Kruskal-Wallis and Kaplan-Meier tests. The background etiology in all SH-HCCs was pure viral in 51.4%, nonalcoholic steatohepatitis (NASH)/alcoholic liver disease (ALD) alone/mixed in 34.3%, and unidentified in normal liver in 14.3%. All SH-HCCS (n=35, 23.3%) and typical SH-HCCs (n=13, 8.6%) had higher NASH/ALD. Limited SH-HCCs (n=22, 14.6%) had higher ALD (all P<0.05). Typical SH-HCCs tended to have more NASH (P=0.054). Steatotic-HCCs (n=13, 9%) and C-HCCs (n=102, 68%) had higher pure viral etiology and serum CRP (all P<0.05). CRP and SAA were positive in 69% and 27% of the tumors, respectively. SAA positivity correlated with ALD (P=0.026). In the overall group disease-free survival rates at 1, 5, 10, and 20 years were 97.0%, 82.3%, 79.6%, and 77.2%, respectively. Demographics, tumor characteristics, CRP and SAA positivity, and survival were similar between the groups (P>0.05). SH-HCC is heterogenous in terms of underlying etiologies, and can be seen in NASH/ALD, pure viral and noncirrhotic/normal background. The ≥50% cutoff for the definition of SH-HCC can lead to overlook ALD-related SH-HCC. Steatotic-HCC seems more similar to C-HCC rather than SH-HCC, but none of them feature as a different prognostic group.

Hepatocellular Carcinomas: Towards a pathomolecular approach

Molecular analysis of primary liver malignancies has provided a refinement of the pathological diagnosis of this entity and the identification of an increasing number of tumor subtypes of hepatocellular proliferation, either malignant (hepatocellular carcinomas) or benign (hepatocellular adenomas). Besides the diagnosis, a combined pathomolecular approach can also provide further insights into patient prognosis, and help select patients who can benefit from targeted therapies. Hepatocellular carcinomas define a heterogeneous group of malignant hepatocellular proliferation at various levels: macroscopic, histological and molecular. While most carcinomas occur in patients with chronic liver diseases and advanced fibrosis in the background liver, some arise from the malignant transformation of a pre-existing hepatocellular adenoma. TERT promoter mutations are the most frequent genomic alterations observed in the process of malignancy, and they occur early in the process of liver carcinogenesis. Overall, a more active biopsy strategy should be considered a key step in the management of patients with HCC.

New Names for Old Tumors

OBJECTIVES

Previous studies described "clear cell" hepatocellular carcinoma (HCC), although definitions have varied. New clear cell subtypes of HCC have been proposed, including chromophobe (C-HCC), steatohepatitic (SH-HCC), and steatotic (S-HCC), and this study assessed the utility and clinical-pathologic profile of these subtypes.

METHODS

Current histologic definitions, including 3 separate proposed definitions for SH-HCC, were applied to tumors previously characterized as clear cell HCC. Histologic and clinical variables were analyzed.

RESULTS

Of 66 HCCs, 51 (77%) were classified using modern definitions, including 34 SH-HCCs, 15 S-HCCs, and 2 C-HCCs. Compared with the most permissive SH-HCC definition, the other 2 definitions designated 30 and 25 SH-HCCs (-12% and -26% cases, respectively). Unsurprisingly, S-HCC and SH-HCC were associated with steatotic clear cells (P < .0001). S-HCC was also more typically early type and low grade (P = .0017). The remaining unclassified clear cell HCCs were associated with flocculent (rather than steatotic or optically clear) cytoplasm (P < .0001) but otherwise demonstrated no discrete clinical-pathologic profile.

CONCLUSIONS

Current definitions could be used to reclassify the majority of "clear cell" HCCs. The subtypes are significantly correlated with a few variables, suggesting valid differences of the subtypes, although additional study is warranted, particularly to standardize the definition of SH-HCC.

Small Steatotic HCC: A Radiological Variant Associated With Improved Outcome After Ablation

Percutaneous thermal ablation is a validated treatment option for small hepatocellular carcinoma (HCC). Steatotic HCC can be reliably detected by magnetic resonance imaging. To determine the clinical relevance of this radiological variant, we included 235 patients (cirrhosis in 92.3%, classified Child-Pugh A in 97%) from a prospective database on percutaneous thermal ablation for <3 cm HCC. Among these patients, 52 (22.1%) had at least one steatotic HCC nodule. Nonalcoholic steatohepatitis was more frequent in patients with than without steatotic HCC (P = 0.057), whereas body mass index, diabetes mellitus, liver steatosis, and liver fat content did not differ between groups. Liver disease was less advanced in patients with than without steatotic HCC: lower total bilirubin ( - 2.1 µmol/L; P = 0.035), higher albumin (+0.8 g/L; P = 0.035), and lower Model for End-Stage Liver Disease score (-0.8; P = 0.014). Tumor phenotype was less aggressive in patients with steatotic HCC: lower alpha-fetoprotein (AFP) concentration (P = 0.019), less frequent AFP > 100 ng/mL (P = 0.045), and multifocality (P = 0.015). During the follow-up (median: 28.3 months), overall mortality (3.8% vs. 23.5%; P = 0.001) and HCC-specific mortality (0.0% vs. 14.2%; P = 0.002) rates were lower in patients with steatotic HCC. Early (<2 years) recurrence was also less frequent (32.7% vs. 49.2%; P = 0.041). The mean time to intrahepatic distant recurrence (16.4 vs. 9 months, P = 0.006) and the median time to recurrence and recurrence-free survival (32.4 vs. 18.6 months, P = 0.024 and 30.4 vs. 16.4 months, P = 0.018) were longer in patients with steatotic versus nonsteatotic HCC. The 3-year overall survival was 94.4% and 70.9% in steatotic and nonsteatotic HCC (P = 0.008). In multivariate analysis, steatotic HCC (hazard ratio = 0.12; P = 0.039) and AFP (HR=1.002; P < 0.001) independently predicted overall survival. Conclusion: Small steatotic HCC detected by magnetic resonance imaging is associated with a less aggressive tumor phenotype. In patients with such radiological variant, percutaneous thermal ablation results in improved outcome.

Characterizing the mechanism behind the progression of NAFLD to hepatocellular carcinoma

Hepatocellular carcinoma (HCC) developed in non-alcoholic fatty liver disease (NAFLD) individuals presents substantial clinical and biological characteristics, which remain to be elucidated. Its occurrence in noncirrhotic patients raises issues regarding surveillance strategies, which cannot be considered as cost-effective given the high prevalence of obesity and metabolic syndrome, and furthermore delineates specific oncogenic process that could be targeted in the setting of primary or secondary prevention. In this context, the identification of a genetic heterogeneity modulating HCC risk as well as specific biological pathways have been made possible through genome-wide association studies, development of animal models and in-depth analyses of human samples at the pathological and genomic levels. These advances must be confirmed and pursued to pave the way for personalized management of NAFLD-related HCC.

Steatohepatitic Variant of Hepatocellular Carcinoma Is Associated With Both Alcoholic Steatohepatitis and Nonalcoholic Steatohepatitis: A Study of 2 Cohorts With Molecular Insights

Steatohepatitic hepatocellular carcinoma (SH-HCC) is a variant of hepatocellular carcinoma (HCC) with established association with nonalcoholic steatohepatitis (NASH), while its association with alcoholic steatohepatitis (ASH) is unclear. We studied 2 cohorts of patients who underwent resection for HCC in the setting of steatohepatitis. In our Mount Sinai (New York) cohort, we found SH-HCC in 17/24 (71%) patients with NASH and in 14/19 (74%) patients with ASH, while SH-HCC was the predominant tumor morphology in 12/24 (50%) in the NASH group and 9/19 (47%) in the ASH group. Upon review, 12/19 patients diagnosed with ASH also had diabetes and/or a body mass index >30. When these patients were removed, we still found similar rates of SH-HCC (6/7 [86%] showed SH-HCC, while SH-HCC was predominant in 3/7 [43%]. Interestingly, glycogenated hepatocyte nuclei were seen in the nontumor liver in 4/7 (57%) of these cases. In our Japan cohort, we also found similar rates of SH-HCC in NASH and ASH patients with HCC, 15/58 (26%), and 16/45 (36%), respectively. We determined molecular subclassification of tumors from the Japan cohort and found no difference in the distribution of S1, S2 and S3 subclasses among the ASH and NASH groups, though, among cases of SH-HCC, there was a trend toward an association of ASH with S1 (P=0.054) and NASH with S3 (P=0.052). Our study shows that SH-HCC is common in both ASH and NASH and that both underlying liver diseases produce tumors with similar molecular profiles, though different pathways may underlie the development of SH-HCC in ASH versus NASH.

Hepatocellular Carcinoma: Role of Pathology in the Era of Precision Medicine

Hepatocellular carcinoma (HCC) is a morphologically heterogeneous tumor with variable architectural growth patterns and several distinct histologic subtypes. Large-scale attempts have been made over the past decade to identify targetable genomic alterations in HCC; however, its translation into clinical personalized care remains a challenge to precision oncology. The role of pathology is no longer limited to confirmation of diagnosis when radiologic features are atypical. Pathology is now in a position to predict the underlying molecular alteration, prognosis, and behavior of HCC. This review outlines various aspects of histopathologic diagnosis and role of pathology in cutting-edge diagnostics of HCC.

High Squalene Epoxidase in Tumors Predicts Worse Survival in Patients With Hepatocellular Carcinoma: Integrated Bioinformatic Analysis on NAFLD and HCC

This study aimed to identify candidate biomarkers for predicting outcomes in nonalcoholic fatty liver disease (NAFLD) and hepatocellular carcinoma (HCC). Using Gene Expression Omnibus and The Cancer Genome Atlas (TCGA) databases, we identified common upregulated differential expressed genes (DEGs) in patients with NAFLD/nonalcoholic steatohepatitis (NASH) and HCC and conducted survival analysis of these upregulated DEGs with HCC outcomes. Two common upregulated DEGs including squalene epoxidase (SQLE) and EPPK1 messenger RNA (mRNA) were significantly upregulated in NAFLD, NASH, and HCC tissues, both in GSE45436 (P < .001) and TCGA profile (P < .001). Both SQLE and EPPK1 mRNA were upregulated in 15.56% and 8.06% patients with HCC in TCGA profile. Overexpression of SQLE in tumors was significantly associated with worse overall survival (OS) and disease-free survival (DFS) in patients with HCC (log-rank P = .027 and log-rank P = .048, respectively), while no statistical significances of OS and DFS were found in EPPK1 groups (both log-rank P > .05). For validation, SQLE upregulation contributed to significantly worse OS in patients wih HCC using Kaplan-Meier plotter analysis (hazard ratio = 1.43, 95% confidence interval: 1.01-2.02, log-rank P = .043). In addition, high level of SQLE significantly associated with advanced neoplasm histologic grade, advanced AJCC stage, and α-fetoprotein elevation (P = .036, .045, and .029, respectively). Squalene epoxidase is associated with OS and DFS and serves as a novel prognostic biomarker for patients with HCC.

Steatohepatitic hepatocellular carcinoma: imaging findings with clinicopathological correlation

AIM

To evaluate the clinicopathological and computed tomography (CT) and magnetic resonance imaging (MRI) findings of steatohepatitic hepatocellular carcinoma (SH-HCC).

MATERIALS AND METHODS

Clinicopathological and radiological features were evaluated in 20 patients with SH-HCC. The diagnosis of SH-HCC was made histologically if the tumour had four of the following five characteristics: steatosis (>5% tumour cells), ballooning, Mallory-Denk bodies, interstitial fibrosis, and inflammation. All patients underwent dynamic CT and MRI. CT and MRI images were reviewed for morphological features including tumour size, presence, and distribution of fat, and patterns and degree of contrast enhancement.

RESULTS

Obesity, hypertension, and history of heavy alcohol intake were common clinical findings observed in 10 (50%), 13 (65%), and 11 (55%) of the 20 patients, respectively. Steatosis and steatohepatitis were pronounced in the background liver in 12 (60%) and 10 (50%) patients, respectively. SH-HCC was moderately differentiated in 18 patients (90%) and well differentiated in two (10%). Pathologically, steatohepatitic features were diffuse in 12 (60%) of the 20 tumours and focal in eight (40%). Tumour size and the percentage of intratumoural steatosis were not correlated (r=0.17, p=0.47). On CT, 16 (80%) patients showed arterial phase enhancement and delayed washout. On MRI, 16 (80%) of 20 tumours showed prominent fatty deposition (10 diffusely, six focally) with arterial phase enhancement.

CONCLUSIONS

SH-HCC is likely to show prominent fatty deposits with arterial phase enhancement on CT and MRI. A hypervascular lesion with prominent fatty change should raise the diagnostic suspicion of SH-HCC.

Lipid Metabolism in Development and Progression of Hepatocellular Carcinoma

: Metabolic reprogramming is critically involved in the development and progression of cancer. In particular, lipid metabolism has been investigated as a source of energy, micro-environmental adaptation, and cell signalling in neoplastic cells. However, the specific role of lipid metabolism dysregulation in hepatocellular carcinoma (HCC) has not been widely described yet. Alterations in fatty acid synthesis, β-oxidation, and cellular lipidic composition contribute to initiation and progression of HCC. The aim of this review is to elucidate the mechanisms by which lipid metabolism is involved in hepatocarcinogenesis and tumour adaptation to different conditions, focusing on the transcriptional aberrations with new insights in lipidomics and lipid zonation. This will help detect new putative therapeutic approaches in the second most frequent cause of cancer-related death.

Clinicopathological features of hepatocellular carcinoma with fatty change: Tumors with macrovesicular steatosis have better prognosis and aberrant expression patterns of perilipin and adipophilin

The clinicopathological characteristics of steatosis in hepatocellular carcinoma (HCC) remain unclear. Here, we elucidate the features of macrovesicular steatosis (MaS) and microvesicular steatosis (MiS) in HCC and their relationships with background liver steatosis. A total of 165 HCC lesions were classified as MaS-HCC, MiS-HCC, or conventional HCC (cHCC) according to the cutoff value of 30% MaS or MiS in tumor cells. We analyzed the clinicopathological differences among these groups. MaS-HCC had less portal vein invasion, a higher proportion of HCC with intratumoral fibrosis, and a lower cumulative risk of recurrence than MiS-HCC or cHCC. Moreover, both MaS-HCC and MiS-HCC had lower incidences of hepatitis virus infection and higher levels of HbA1c than cHCC. Background liver steatosis was also higher in MaS-HCC than in cHCC. Immunohistochemical expression of perilipin (Plin1) and adipophilin (ADRP), major proteins expressed on lipid droplet membranes, revealed that almost all lipid droplets in HCC were Plin1 negative, whereas those in background liver were positive. In contrast, ADRP was expressed on lipid droplets in both HCC and background liver. We concluded that MaS-HCC and MiS-HCC were associated with metabolic abnormalities but exhibited different biologic behaviors. Furthermore, lipid droplets in HCC were pathophysiologically different from those in background liver.

Precision pathology analysis of the development and progression of hepatocellular carcinoma: Implication for precision diagnosis of hepatocellular carcinoma

Outcomes for patients with hepatocellular carcinoma (HCC) remain poor because the condition is often unresponsive to the available treatments. Consequently, the early and precise diagnosis of HCC is crucial to achieve improvements in prognosis. For patients with chronic liver disease, the assessment of liver fibrosis is also important to ascertain both the staging of fibrosis and the risk of HCC occurrence. Early HCC was first described in 1991 in Japan and was defined internationally in 2009. As the concept of early HCC spread, the multistage hepatocarcinogenesis process became accepted. Consequently, improvements in imaging technology made the early diagnosis of HCC possible. At present, the most appropriate therapeutic strategy for HCC is determined using an integrated staging system that assesses the tumor burden, the degree of liver dysfunction and the patient performance status; however, pathological and molecular features are not taken into account. The recent introduction of several new therapeutic agents will change the treatment strategy for HCC. Against this background, HCC subclassification based on tumor cellular and microenvironmental characteristics will become increasingly important. In this review, we give an overview of how pathological analysis contributes to understanding the development and progression of HCC and establishing a precision diagnosis of HCC.

Hepatocellular carcinoma in non-alcoholic fatty liver disease (NAFLD) - pathological evidence for a predominance of steatohepatitic inflammatory non-proliferative subtype

OBJECTIVES

This study evaluated clinical and pathological aspects of patients with hepatocellular carcinoma (HCC) secondary to non-alcoholic fatty liver disease (NAFLD) and related these factors to immunohistochemical markers representative of the proliferative class.

METHODS

We evaluated 35 HCC nodules from 21 patients diagnosed with NAFLD undergoing liver resection (n=12) or liver transplantation (n=8) or both (n=1). Demographic, clinical and biochemical data were compared to histological features and to immunohistochemical reactivity for K19 and Ki-67.

RESULTS

Cirrhosis was present in 58% of patients. Ages ranged from 50 to 77 years. Sixteen patients (76%) were male and had type 2 diabetes mellitus, 81% had arterial hypertension, and 90% had BMI above 25 kg/m². Alpha-fetoprotein levels were normal in 62% of patients. Twenty-five (70%) nodules were diagnosed as "steatohepatitic HCC". Only 32% of the nodules presented high levels of Ki-67 (>10%) and/or K19 (>5%), although 63% were poorly differentiated (G.3/G.4) according to Edmondson & Steiner grading system. K19 positivity (>5%) was associated with higher degree of intratumoral inflammation (G.2/G.3), and with fibrosis, both at the center of the tumor and at the tumor front, whereas Ki-67 positivity (>10%) was associated with ballooning of neoplastic cells and occurred in more than 70% in non-cirrhotic patients.

CONCLUSION

NAFLD-related HCC was found in non-cirrhotic patients in 42% of cases, alpha-fetoprotein level was normal in 63% and "steatohepatitic HCC" was the predominant histological type. Immunoexpression of K19 and/or Ki-67 occurred in 32% of the nodules and were associated with intratumoral inflammation and ballooning, suggesting that HCC in MtS may be preferentially "an inflammatory, non-proliferative subtype of HCC".

HIF-2α upregulation mediated by hypoxia promotes NAFLD-HCC progression by activating lipid synthesis via the PI3K-AKT-mTOR pathway

Non-alcoholic fatty liver disease (NAFLD) is a relevant risk factor for developing hepatocellular carcinoma (HCC). Steatohepatitic HCC (SH-HCC), characterized by HCC with steatosis, is influenced by lipid metabolism disorders. A hypoxic microenvironment is common in HCC and affects lipid metabolism. However, whether hypoxia-induced HIF-2α upregulation exacerbates lipid accumulation to contribute to SH-HCC progression remains unclear. In this study, we demonstrated that HIF-2α was elevated in tissues from NAFLD-HCC patients and was associated with survival. Under hypoxic conditions, upregulated HIF-2α was accompanied by lipid accumulation and PI3K-AKT-mTOR pathway activation. HIF-2α knockdown (KD) in steatotic HCC ameliorated triglyceride accumulation and steatosis. HIF-2α-KD steatotic HCC showed minimal lipid synthesis in a hypoxic environment, which contributes to a reduction in malignant behaviours. However, treatment with MHY1485 restored these behaviours. STAM mice, a mouse model that develops NAFLD-HCC, exhibit more rapid tumour progression upon exposure to hypoxia. STAM mice treated with INK-128 presented abrogated mTOR expression and tumour progression under hypoxic conditions with lower triglycerides and steatosis. In conclusion, in a hypoxic microenvironment, HIF-2α upregulation promotes steatotic HCC progression by activating lipid synthesis via the PI3K-AKT-mTOR pathway. Therefore, HIF-2α can be a biomarker and target in developing specific therapeutic measures for NAFLD-HCC patients.

Renin-angiotensin inhibitors were associated with improving outcomes of hepatocellular carcinoma with primary hypertension after hepatectomy

Background

The activation of the renin-angiotensin system (RAS) promotes tumor progression. In this study, we aimed to assess whether RAS inhibitors (RASIs) could improve the outcome of hepatocellular carcinoma (HCC) patients with primary hypertension after curative liver resection.

Methods

Data on 387 consecutive patients with primary hypertension who underwent curative liver resection for HCC were reviewed. The study population was divided into two groups based on the type of anti-hypertensive medications: the RASI group (patients using RASIs) and the non-RASI group (patients using other anti-hypertensive drugs but not RASIs). Kaplan-Meier curves, log-rank tests and cox proportional hazards regression models were used to analyze time to recurrence (TTR) and overall survival (OS).

Results

There were 144 (37.2%) patients in RASI group and 243 (62.8%) in non-RASI group. The preoperative clinicopathological features were comparable between the two groups. Kaplan-Meier curves demonstrated HCC patients with RASIs had a longer TTR and OS than the patients with non-RASIs (both P<0.001). On multivariate analysis, RASIs administration was identified as an independent prognostic factor for TTR [hazard ratio (HR) =0.52, 95% confidence interval (CI), 0.38-0.70, P<0.001] and OS (HR =0.50, 95% CI, 0.34-0.74, P<0.001). Patients in the RASI group had lower rates of extrahepatic metastases than patients in the non-RASI group (2.8% vs. 7.8%, P<0.042).

Conclusions

Targeting the RAS was associated with a reduced risk of recurrence, decreased rate of extrahepatic metastases and prolonged survival of HCC patients with primary hypertension after curative liver resection.

Lipid Related Genes Altered in NASH Connect Inflammation in Liver Pathogenesis Progression to HCC: A Canonical Pathway

Nonalcoholic steatohepatitis (NASH) is becoming a public health problem worldwide. While the number of research studies on NASH progression rises every year, sometime their findings are controversial. To identify the most important and commonly described findings related to NASH progression, we used an original bioinformatics, integrative, text-mining approach that combines PubMed database querying and available gene expression omnibus dataset. We have identified a signature of 25 genes that are commonly found to be dysregulated during steatosis progression to NASH and cancer. These genes are implicated in lipid metabolism, insulin resistance, inflammation, and cancer. They are functionally connected, forming the basis necessary for steatosis progression to NASH and further progression to hepatocellular carcinoma (HCC). We also show that five of the identified genes have genome alterations present in HCC patients. The patients with these genes associated to genome alteration are associated with a poor prognosis. In conclusion, using an integrative literature- and data-mining approach, we have identified and described a canonical pathway underlying progression of NASH. Other parameters (e.g., polymorphisms) can be added to this pathway that also contribute to the progression of the disease to cancer. This work improved our understanding of the molecular basis of NASH progression and will help to develop new therapeutic approaches.

Jak-Stat Signaling Induced by Interleukin-6 Family Cytokines in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors worldwide. It can be caused by chronic liver cell injury with resulting sustained inflammation, e.g., triggered by infections with hepatitis viruses B (HBV) and C (HCV). Death of hepatocytes leads to the activation of compensatory mechanisms, which can ultimately result in liver fibrosis and cirrhosis. Another common feature is the infiltration of the liver with inflammatory cells, which secrete cytokines and chemokines that act directly on the hepatocytes. Among several secreted proteins, members of the interleukin-6 (IL-6) family of cytokines have emerged as important regulatory proteins that might constitute an attractive target for therapeutic intervention. The IL-6-type cytokines activate multiple intracellular signaling pathways, and especially the Jak/STAT cascade has been shown to be crucial for HCC development. In this review, we give an overview about HCC pathogenesis with respect to IL-6-type cytokines and the Jak/STAT pathway. We highlight the role of mutations in genes encoding several proteins involved in the cytokine/Jak/STAT axis and summarize current knowledge about IL-6 family cytokines in this context. We further discuss possible anti-cytokine therapies for HCC patients in comparison to already established therapies.

Hepatocellular carcinoma with non-B and non-C hepatitis origin: epidemiology in Japan and surgical outcome

During the last two decades, there has been a dramatic increase in so-called non-B non-C hepatocellular carcinoma (NBNC HCC) in Japan. Majority of NBNC HCC are considered as so-called metabolic HCC and some could be related to occult HBV infection. Although there have been some reports on histological features predominant in metabolic HCC, very few specific driver genes for NBNC HCC have been reported. Most of the NBNC HCC are found incidentally and are relatively large in size. Since liver function is generally normal or subnormal, such patients have a higher chance for undergoing curative surgery. Although there has been slightly conflicting long-term outcomes reported for NBNC HCC, slightly better outcomes may be expected compared to other etiologies after curative surgery. However, risk of recurrence depends on the background liver. NBNC HCC in cirrhotic patients have a persistently higher risk of tumor recurrence requiring a long-term postoperative surveillance. It would be safe to conclude at this moment that NBNC HCCs should be treated using the same surgical strategy as HCCs with viral origin, same operative indications and same follow-up protocol.

Hepatocellular carcinoma with non-B and non-C hepatitis origin: epidemiology in Japan and surgical outcome

During the last two decades, there has been a dramatic increase in so-called non-B non-C hepatocellular carcinoma (NBNC HCC) in Japan. Majority of NBNC HCC are considered as so-called metabolic HCC and some could be related to occult HBV infection. Although there have been some reports on histological features predominant in metabolic HCC, very few specific driver genes for NBNC HCC have been reported. Most of the NBNC HCC are found incidentally and are relatively large in size. Since liver function is generally normal or subnormal, such patients have a higher chance for undergoing curative surgery. Although there has been slightly conflicting long-term outcomes reported for NBNC HCC, slightly better outcomes may be expected compared to other etiologies after curative surgery. However, risk of recurrence depends on the background liver. NBNC HCC in cirrhotic patients have a persistently higher risk of tumor recurrence requiring a long-term postoperative surveillance. It would be safe to conclude at this moment that NBNC HCCs should be treated using the same surgical strategy as HCCs with viral origin, same operative indications and same follow-up protocol.

Clinical features of hepatocellular carcinoma in nonalcoholic fatty liver disease patients without advanced fibrosis

BACKGROUND AND AIM

The prevalence of hepatocellular carcinoma (HCC) associated with nonalcoholic fatty liver disease (NAFLD-HCC) is increasing. Unfortunately, NAFLD frequently develops into HCC without liver cirrhosis. Therefore, we investigated the clinical features of HCC in NAFLD patients without advanced fibrosis.

METHODS

We compared clinical characteristics, survival rates, and recurrence rates between 104 NAFLD-HCC patients diagnosed between January 2000 and December 2016, including 35 without (F0-2) and 69 with advanced fibrosis (F3-F4). Risk factors associated with survival and recurrence were evaluated.

RESULTS

In total, 66.3% of those diagnosed had advanced fibrosis, 58.8% in men and 80.5% in women (men vs women, P = 0.03). In NAFLD-HCC without advanced fibrosis, tumor size was significantly larger and liver histological activity was lower than those in patients with advanced fibrosis. Survival rates between the two groups did not differ. Among those achieving curative treatment, the recurrence rate was significantly lower in NAFLD-HCC without advanced fibrosis (P < 0.01). Risk factors of recurrence were male gender, lower serum albumin, and advanced fibrosis.

CONCLUSIONS

In men, HCC tended to develop from NAFLD without advanced fibrosis. Although tumor size in NAFLD-HCC without advanced fibrosis is significantly larger, the recurrence rate is significantly lower. Surgical therapy should be strongly considered in these cases.

Altered serum acylcarnitine profile is associated with the status of nonalcoholic fatty liver disease (NAFLD) and NAFLD-related hepatocellular carcinoma

Metabolic disturbance of lipids is a hallmark of nonalcoholic fatty liver disease (NAFLD). In this study, we measured the serum levels of 15 acylcarnitine species of various carbon chain lengths from 2 to 18 in 241 patients with biopsy-proven NAFLD, including 23 patients with hepatocellular carcinoma (HCC), and analyzed the relationship between serum acylcarnitine profile and NAFLD status. Long-chain acylcarnitines AC14:1 and AC18:1 increased gradually with the progression of fibrosis and further increased in patients with HCC, whereas the middle-chain acylcarnitine AC5:0 exhibited the opposite trend. In particular, AC18:1, which we previously showed to possess a tumor promoting effect, was significantly elevated in patients with HCC compared to those without HCC. In addition, long-chain acylcarntines including AC18:1 were positively correlated with serum levels of inflammatory cytokines. Although none of the acylcarnitine species were independently associated with the presence of HCC, (AC16:0 + AC18:1)/AC2:0, an index for the diagnosis of carnitine palmitoyltransferase 2 (CPT2) deficiency, was independently associated with the presence of HCC after adjusting for age and liver fibrosis stage, likely reflecting the downregulation of CPT2 in HCC tissues. Thus, serum acylcarnitine profiles changed significantly according to the status of NAFLD, which may be implicated in the pathogenesis of NAFLD.

Update on hepatocellular carcinoma: Pathologists’ review

Histopathologic diversity and several distinct histologic subtypes of hepatocellular carcinoma (HCC) are well-recognized. Recent advances in molecular pathology and growing knowledge about the biology associated with distinct histologic features and immuno-profile in HCC allowed pathologists to update classifications. Improving sub-classification will allow for more clinically relevant diagnoses and may allow for stratification into biologically meaningful subgroups. Therefore, immuno-histochemical and molecular testing are not only diagnostically useful, but also are being incorporated as crucial components in predicting prognosis of the patients with HCC. Possibilities of targeted therapy are being explored in HCC, and it will be important for pathologists to provide any data that may be valuable from a theranostic perspective. Herein, we review and provide updates regarding the pathologic sub-classification of HCC. Pathologic diagnostic approach and the role of biomarkers as prognosticators are reviewed. Further, the histopathology of four particular subtypes of HCC: Steatohepatitic, clear cell, fibrolamellar and scirrhous - and their clinical relevance, and the recent consensus on combined HCC-cholangiocarcinoma is summarized. Finally, emerging novel biomarkers and new approaches to HCC stratification are reviewed.

Steatotic and nonsteatotic scirrhous hepatocellular carcinomas reveal distinct clinicopathological features

We investigated the clinicopathological and molecular characteristics of scirrhous hepatocellular carcinoma (HCC) to elucidate its uniqueness. Samples from 120 resected HCC cases underwent immunohistochemical analysis. Tumor area containing fibrous stroma and the percentage of steatotic cells within the tumor were evaluated. In our previous report, tumors were immunohistochemically subclassified as biliary/stem cell markers-positive (B/S) (cytokeratin 19 and/or sal-like protein 4 and/or epithelial cell adhesion molecule positive), Wnt/β-catenin signaling-related markers-positive (W/B) (β-catenin and/or glutamine synthetase positive), or all markers-negative (-/-) groups. Thirty-seven cases (31%) with fibrous stroma making up ≥50% of the largest tumor area were defined as scirrhous HCC (sHCC); the other 83 cases (69%) were categorized as common HCC (cHCC). Clinicopathologically, sHCC had fewer poorly differentiated tumors (P = .037) and a higher percentage of cases with steatosis (P = .025) than cHCC. sHCC cases were further divided into two subgroups: those with ≥5% steatotic cells (steatotic sHCC) and those with <5% steatotic cells (nonsteatotic sHCC). Hepatitis B virus infection was more frequent in nonsteatotic sHCC (P = .029), and non-B, non-C cases were more frequent in steatotic sHCC (P = .006). Steatotic sHCC tended to have a longer time to recurrence than nonsteatotic sHCC and cHCC. Most nonsteatotic sHCC cases belonged to B/S group, whereas most steatotic sHCC belonged to -/- group. The same tendency in sHCC was shown in another cohort. Distinct features were seen in steatotic and nonsteatotic sHCC, and both sHCC subgroups exhibited different clinicopathological and molecular features from cHCC. These findings support the hypothesis that sHCC is an independent entity.

Steatohepatitic Variant of Hepatocellular Carcinoma: A Focused Review

The incidence of hepatocellular carcinoma (HCC) has steadily increased over the past three decades and currently ranks as the fifth most common cancer worldwide. Likewise, non-alcoholic fatty liver disease (NAFLD), a known risk factor for the development of HCC, has emerged as the most common liver disease in Western countries. The underlying pathogenesis of NAFLD-related HCC remains unclear. The steatohepatitic variant of HCC (SH-HCC) typically presents in patients with metabolic risk factors and either cirrhotic or non-cirrhotic NAFLD and shares many of the histological features found in non-alcoholic steatohepatitis (NASH). Given their similar morphological features, distinguishing SH-HCC from background fatty liver can be a diagnostic challenge. Immunohistochemical studies to characterize and assist in the diagnosis are relatively limited. Whether the steatotic phenotype of SH-HCC results from the tumor's adaptive response to an environment rich in fatty acids or from an independent pathogenic pathway remains to be seen. This review aims to summarize what is currently known regarding the pathogenesis and clinicopathological features of SH-HCC.

Lipid Metabolic Reprogramming in Hepatocellular Carcinoma

Metabolic reprogramming for adaptation to the local environment has been recognized as a hallmark of cancer. Although alterations in fatty acid (FA) metabolism in cancer cells have received less attention compared to other metabolic alterations such as glucose or glutamine metabolism, recent studies have uncovered the importance of lipid metabolic reprogramming in carcinogenesis. Obesity and nonalcoholic steatohepatitis (NASH) are well-known risk factors of hepatocellular carcinoma (HCC), and individuals with these conditions exhibit an increased intake of dietary FAs accompanied by enhanced lipolysis of visceral adipose tissue due to insulin resistance, resulting in enormous exogenous FA supplies to hepatocytes via the portal vein and lymph vessels. This “lipid-rich condition” is highly characteristic of obesity- and NASH-driven HCC. Although the way in which HCC cells adapt to such a condition and exploit it to aid their progression is not understood, we recently obtained new insights into this mechanism through lipid metabolic reprogramming. In addition, accumulating evidence supports the importance of lipid metabolic reprogramming in various situations of hepatocarcinogenesis. Thus, in this review, we discuss the latest findings regarding the role of FA metabolism pathways in hepatocarcinogenesis, focusing on obesity- and NASH-driven lipid metabolic reprogramming.

Clinicopathological investigation of steatohepatitic hepatocellular carcinoma: A multicenter study using immunohistochemical analysis of adenoma-related markers

AIMS

Steatohepatitic hepatocellular carcinoma (SH-HCC) is a newly proposed concept, which shows histological features of steatohepatitis in HCC lesions, and it is strongly associated with metabolic syndrome (MS) and steatosis/steatohepatitis in non-cancerous lesions. Recently, a substantial number of HCC associated with MS were reported to have developed from pre-existing inflammatory hepatocellular adenoma (HCA). To elucidate the characteristic features of SH-HCC, we clinicopathologically investigated strictly diagnosed SH-HCC and non-SH-HCC (standard HCC).

METHODS

This was a retrospective multicenter study. A clinicopathological investigation was undertaken to compare 62 cases with SH-HCC features to 31 age- and sex-matched standard HCC cases, including an immunohistochemical study using markers for classification of HCA and diagnosis of HCC.

RESULTS

The characteristic features of SH-HCC compared with standard HCC include a higher rate of complications of MS, more frequent non-alcoholic fatty liver disease as an underlying liver disease, and HCC development in non-cirrhotic liver. The rate of solitary tumors showed no difference between the two groups, but the median diameter of the main tumor was greater in SH-HCCs (45 mm/20 mm, P = 0.01). The HCCs were mostly moderately differentiated, and the patterns were mainly trabecular in both groups. Positive findings for serum amyloid A and C-reactive proteins, classification markers of inflammatory HCA, were significantly higher in cancerous lesions of SH-HCC cases (50%/13%, P < 0.01 and 42%/16%, respectively; P = 0.01).

CONCLUSIONS

We confirmed that SH-HCC was strongly associated with MS and NAFLD, and found that classification markers of inflammatory HCA were significantly higher in SH-HCC. Further studies are needed to elucidate the relationship between SH-CCC and HCA for understanding the carcinogenic pathways in these diseases.

CPT2 downregulation adapts HCC to lipid-rich environment and promotes carcinogenesis via acylcarnitine accumulation in obesity

OBJECTIVE

Metabolic reprogramming of tumour cells that allows for adaptation to their local environment is a hallmark of cancer. Interestingly, obesity-driven and non-alcoholic steatohepatitis (NASH)-driven hepatocellular carcinoma (HCC) mouse models commonly exhibit strong steatosis in tumour cells as seen in human steatohepatitic HCC (SH-HCC), which may reflect a characteristic metabolic alteration.

DESIGN

Non-tumour and HCC tissues obtained from diethylnitrosamine-injected mice fed either a normal or a high-fat diet (HFD) were subjected to comprehensive metabolome analysis, and the significance of obesity-mediated metabolic alteration in hepatocarcinogenesis was evaluated.

RESULTS

The extensive accumulation of acylcarnitine species was seen in HCC tissues and in the serum of HFD-fed mice. A similar increase was found in the serum of patients with NASH-HCC. The accumulation of acylcarnitine could be attributed to the downregulation of carnitine palmitoyltransferase 2 (CPT2), which was also seen in human SH-HCC. CPT2 downregulation induced the suppression of fatty acid β-oxidation, which would account for the steatotic changes in HCC. CPT2 knockdown in HCC cells resulted in their resistance to lipotoxicity by inhibiting the Src-mediated JNK activation. Additionally, oleoylcarnitine enhanced sphere formation by HCC cells via STAT3 activation, suggesting that acylcarnitine accumulation was a surrogate marker of CPT2 downregulation and directly contributed to hepatocarcinogenesis. HFD feeding and carnitine supplementation synergistically enhanced HCC development accompanied by acylcarnitine accumulation in vivo.

CONCLUSION

In obesity-driven and NASH-driven HCC, metabolic reprogramming mediated by the downregulation of CPT2 enables HCC cells to escape lipotoxicity and promotes hepatocarcinogenesis.