Viral hepatitis and hepatocellular carcinoma: From molecular pathways to the role of clinical surveillance and antiviral treatment

Hepatocellular carcinoma (HCC) is a global health challenge. Due to the high prevalence in low-income countries, hepatitis B virus (HBV) and hepatitis C virus infections remain the main risk factors for HCC occurrence, despite the increasing frequencies of non-viral etiologies. In addition, hepatitis D virus coinfection increases the oncogenic risk in patients with HBV infection. The molecular processes underlying HCC development are complex and various, either independent from liver disease etiology or etiology-related. The reciprocal interlinkage among non-viral and viral risk factors, the damaged cellular microenvironment, the dysregulation of the immune system and the alteration of gut-liver-axis are known to participate in liver cancer induction and progression. Oncogenic mechanisms and pathways change throughout the natural history of viral hepatitis with the worsening of liver fibrosis. The high risk of cancer incidence in chronic viral hepatitis infected patients compared to other liver disease etiologies makes it necessary to implement a proper surveillance, both through clinical-biochemical scores and periodic ultrasound assessment. This review aims to outline viral and microenvironmental factors contributing to HCC occurrence in patients with chronic viral hepatitis and to point out the importance of surveillance programs recommended by international guidelines to promote early diagnosis of HCC.     

Current impact of viral hepatitis on liver cancer development: The challenge remains

Chronic infections due to hepatitis B and hepatitis C viruses are responsible for most cases of hepatocellular carcinoma (HCC) worldwide, and this association is likely to remain during the next decade. Moreover, viral hepatitis-related HCC imposes an important burden on public health in terms of disability-adjusted life years. In order to reduce such a burden, some major challenges must be faced. Universal vaccination against hepatitis B virus, especially in the neonatal period, is probably the most relevant primary preventive measure against the development of HCC. Moreover, considering the large adult population already infected with hepatitis B and C viruses, it is also imperative to identify these individuals to ensure their access to treatment. Both hepatitis B and C currently have highly effective therapies, which are able to diminish the risk of development of liver cancer. Finally, it is essential for individuals at high-risk of HCC to be included in surveillance programs, so that tumors are detected at an early stage. Patients with hepatitis B or C and advanced liver fibrosis or cirrhosis benefit from being followed in a surveillance program. As hepatitis B virus is oncogenic and capable of leading to liver cancer even in individuals with early stages of liver fibrosis, other high-risk groups of patients with hepatitis B are also candidates for surveillance. Considerable effort is required concerning these strategies in order to decrease the incidence and the mortality of viral hepatitis-related HCC.     

Non-cirrhotic hepatocellular carcinoma in chronic viral hepatitis: Current insights and advancements

Primary liver cancers carry significant morbidity and mortality. Hepatocellular carcinoma (HCC) develops within the hepatic parenchyma and is the most common malignancy originating from the liver. Although 80% of HCCs develop within background cirrhosis, 20% may arise in a non-cirrhotic milieu and are referred to non-cirrhotic-HCC (NCHCC). NCHCC is often diagnosed late due to lack of surveillance. In addition, the rising prevalence of non-alcoholic fatty liver disease and diabetes mellitus have increased the risk of developing HCC on non-cirrhotic patients. Viral infections such as chronic Hepatitis B and less often chronic hepatitis C with advance fibrosis are associated with NCHCC. NCHCC individuals may have Hepatitis B core antibodies and occult HBV infection, signifying the role of Hepatitis B infection in NCHCC. Given the effectiveness of current antiviral therapies, surgical techniques and locoregional treatment options, nowadays such patients have more options and potential for cure. However, these lesions need early identification with diagnostic models and multiple surveillance strategies to improve overall outcomes. Better understanding of the NCHCC risk factors, tumorigenesis, diagnostic tools and treatment options are critical to improving prognosis and overall outcomes on these patients. In this review, we aim to discuss NCHCC epidemiology, risk factors, and pathogenesis, and elaborate on NCHCC diagnosis and treatment strategies.     

Hepatocellular carcinoma in non-alcoholic fatty liver disease: an emerging menace

Hepatocellular carcinoma (HCC) is a common cancer worldwide that primarily develops in cirrhosis resulting from chronic infection by hepatitis B virus and hepatitis C virus, alcoholic injury, and to a lesser extent from genetically determined disorders such as hemochromatosis. HCC has recently been linked to non-alcoholic fatty liver disease (NAFLD), the hepatic manifestation of obesity and related metabolic disorders such as diabetes. This association is alarming due to the globally high prevalence of these conditions and may contribute to the rising incidence of HCC witnessed in many industrialized countries. There is also evidence that NAFLD acts synergistically with other risk factors of HCC such as chronic hepatitis C and alcoholic liver injury. Moreover, HCC may complicate non-cirrhotic NAFLD with mild or absent fibrosis, greatly expanding the population potentially at higher risk. Major systemic and liver-specific molecular mechanisms involved include insulin resistance and hyperinsulinemia, increased TNF signaling pathways, and alterations in cellular lipid metabolism. These provide new targets for prevention, early recognition, and effective treatment of HCC associated with NAFLD. Indeed, both metformin and PPAR gamma agonists have been associated with lower risk and improved prognosis of HCC. This review summarizes current evidence as it pertains to the epidemiology, pathogenesis, and prevention of NAFLD-associated HCC.     

Hepatocellular carcinoma and the risk of occupational exposure

Hepatocellular carcinoma(HCC)is the most common type of liver cancer.The main risk factors for HCC are alcoholism,hepatitis B virus,hepatitis C virus,nonalcoholic steatohepatitis,obesity,type 2 diabetes,cirrhosis,aflatoxin,hemochromatosis,Wilson’s disease and hemophilia.Occupational exposure to chemicals is another risk factor for HCC.Often the relationship between occupational risk and HCC is unclear and the reports are fragmented and inconsistent.This review aims to summarize the current knowledge regarding the association of infective and non-infective occupational risk exposure and HCC in order to encourage further research and draw attention to this global occupational public health problem.     

Factors predicting occurrence and prognosis of hepatitis-B-virus-related hepatocellular carcinoma

Primary liver cancer is an important cause of cancer death,and hepatocellular carcinoma(HCC) accounts for 70%-85% of total liver cancer worldwide.Chronic hepatitis B virus(HBV) infection contributes to > 75% of HCC cases.High serum viral load is the most reliable indicator of viral replication in predicting development of HCC.HBV genotype C is closely associated with HCC in cirrhotic patients aged > 50 years,whereas genotype B is associated with development of HCC in non-cirrhotic young patients and postope...     

Hepatocellular carcinoma in the post-hepatitis C virus era: Should we change the paradigm?

Hepatocellular carcinoma (HCC) is a common and deadly malignancy. The disease usually develops on a background of chronic liver disease. Until recently, the most common etiology was infection with the hepatitis C virus (HCV). The advent of direct-acting antiviral (DAA) therapies has been a major breakthrough in HCV treatment. Sustained virologic response can now be achieved in almost all treated patients, even in patients with a high risk for the development of HCC, such as the elderly or those with significant fibrosis. Early reports raised concerns of a high risk for HCC occurrence after DAA therapy both in patients with previous resection of tumors and those without previous tumors. As the World Health Organization’s goals for eradication of HCV are being endorsed worldwide, the elimination of HCV seems feasible. Simultaneous to the decrease in the burden of cirrhosis from HCV, non-alcoholic fatty liver disease (NAFLD) incidence has been increasing dramatically including significant increased incidence of cirrhosis and HCC in these patients. Surprisingly, a substantial proportion of patients with NAFLD were shown to develop HCC even in the absence of cirrhosis. Furthermore, HCC treatment and potential complications are known to be influenced by liver steatosis. These changes in etiology and epidemiology of HCC suggest the beginning of a new era: The post–HCV era. Changes may eventually undermine current practices of early detection, surveillance and management of HCC. We focused on the risk of HCC occurrence and recurrence in the post–HCV era, the surveillance needed after DAA therapy and current studies in HCC patients with NAFLD.     

Hepatocellular carcinoma in patients with metabolic dysfunction-associated fatty liver disease: Can we stratify at-risk populations?

Metabolic dysfunction-associated fatty liver disease (MAFLD) is a new nomenclature recently proposed by a panel of international experts so that the entity is defined based on positive criteria and linked to pathogenesis, replacing the traditional non-alcoholic fatty liver disease (NAFLD), a definition based on exclusion criteria. NAFLD/MAFLD is currently the most common form of chronic liver disease worldwide and is a growing risk factor for development of hepatocellular carcinoma (HCC). It is estimated than 25% of the global population have NAFLD and is projected to increase in the next years. Major Scientific Societies agree that surveillance for HCC should be indicated in patients with NAFLD/ MAFLD and cirrhosis but differ in non-cirrhotic patients (including those with advanced fibrosis). Several studies have shown that the annual incidence rate of HCC in NAFLD-cirrhosis is greater than 1%, thus surveillance for HCC is cost-effective. Risk factors that increase HCC incidence in these patients are male gender, older age, presence of diabetes and any degree of alcohol consumption. In non-cirrhotic patients, the incidence of HCC is much lower and variable, being a great challenge to stratify the risk of HCC in this group. Furthermore, large epidemiological studies based on the general population have shown that diabetes and obesity significantly increase risk of HCC. Some genetic variants may also play a role modifying the HCC occurrence among patients with NAFLD. The purpose of this review is to discuss the epidemiology, clinical and genetic risk factors that may influence the risk of HCC in NAFLD/MAFLD patients and propose screening strategy to translate into better patient care.     

Prevention of hepatocellular carcinoma: progress and challenges

Hepatocellular carcinoma (HCC) is a lethal cancer for both men and women and is caused by multiple risk factors. Most patients with HCC have an underlying liver disease caused by either chronic viral infection due to hepatitis B or hepatitis C virus or non-viral etiologic risk factors such as alcohol, fatty liver disease, dietary aflatoxin exposure, smoking and diabetes mellitus. While these risk factors are progressively and persistently damaging the liver, the majority of patients show very few symptoms of HCC. By the time symptoms appear the cancer is typically at a very advanced stage with limited options for treatment. In order to prevent death from HCC, it is therefore critically important to reduce the prevalence of the major risk factors, identify and treat those at high risk for development of HCC, and institute effective surveillance strategies for early diagnosis and treatment of HCC. This article reviews the recent progress and current challenges to the prevention of HCC.     

NAFLD-Associated Hepatocellular Carcinoma: a Threat to Patients with Metabolic Disorders

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide, and its prevalence is increasing in relation to the epidemics of obesity and type 2 diabetes mellitus, via non-alcoholic fatty liver disease (NAFLD). Unhealthy lifestyles associated with metabolic disorders are per se risk conditions for NAFLD progression, and specific gene polymorphisms may also favor oncogenesis, particularly in the presence of advanced fibrosis or cryptogenic cirrhosis. However, NAFLD-associated HCC may also develop in non-cirrhotic NAFLD and is frequently diagnosed at a more advanced tumor stage, compared with virus/alcohol-related HCC. This highlights the need for screening programs and long-term surveillance for earlier HCC detection in patients with metabolic risk factors, a policy hindered by the large number of cases at risk, with costs unaffordable by National health systems. New screening tools and cost-utility studies are eagerly awaited to develop more appropriate programs for early detection and treatment of NAFLD-associated HCC.     

Nucleos(t)ide analogs in the prevention of hepatitis B virus related hepatocellular carcinoma

Hepatocellular carcinoma(HCC) is among the most common cancer types and causes of cancer related mortality worldwide.Almost 50% of all HCC cases globally are attributable to chronic hepatitis B virus(HBV) infection.The incidence rates of HCC in untreated Asian subjects with HBV infection was estimated to be 0.2% in inactive carriers,0.6% for those with chronic hepatitis without cirrhosis,and 3.7% for those with compensated cirrhosis.In Western populations,HCC incidences are reported to be 0.02% in inactive carriers,0.3% in subjects with chronic hepatitis without cirrhosis,and 2.2% in subjects with compensated cirrhosis.Despite effective antiviral treatment options which are able to transform chronic hepatitis into an inactive carrier state,the risk of HCC cannot be fully ruled out to exclude those patients from surveillance.Newer nucleos(t)ide analogues(NAs) as entecavir and tenofovir are very potent in terms of sustained virological suppression which leads to improved liver histology.However,they do not have any influence on the ccc DNA or integrated DNA of HBV in the liver.Nonetheless,viral replication is the only modifiable component among the established risk factors for HBV-related HCC with the current treatment options.In this review,it was aimed to summarize cumulative evidence behind the concept of prevention of HBV related HCC by NAs,and to discuss remaining obstacles to eliminate the risk of HCC.     

Expanding the Liver Imaging Reporting and Data System (LI-RADS) v2018 diagnostic population: performance and reliability of LI-RADS for distinguishing hepatocellular carcinoma (HCC) from non-HCC primary liver carcinoma in patients who do not meet strict LI-RADS high-risk criteria

BackgroundHepatocellular carcinoma (HCC) can be diagnosed using imaging criteria in patients at high-risk for HCC, according to Liver Imaging Reporting and Data System (LI-RADS) guidelines. The aim of this study was to determine the diagnostic performance and inter-rater reliability (IRR) of LI-RADS v2018 for differentiating HCC from non-HCC primary liver carcinoma (PLC), in patients who are at increased risk for HCC but not included in the LI-RADS ‘high-risk’ population.MethodsThis retrospective HIPAA-compliant study included a 10-year experience of pathologically-proven PLC at two liver transplant centers, and included patients with non-cirrhotic hepatitis C infection, non-cirrhotic non-alcoholic fatty liver disease, and fibrosis. Two readers evaluated each lesion and assigned an overall LI-RADS diagnostic category, additionally scoring all major, LR-M, and ancillary features.ResultsThe final study cohort consisted of 27 HCCs and 104 non-HCC PLC in 131 patients. The specificity of a ‘definite HCC’ designation was 97% for reader 1 and 100% for reader 2. The IRR was fair for overall LI-RADS category and substantial for most major features.ConclusionIn a population at increased risk for HCC but not currently included in the LI-RADS ‘high-risk’ population, LI-RADS v2018 demonstrated very high specificity for distinguishing pathologically-proven HCC from non-HCC PLC.     

Hepatocellular carcinoma surveillance:An evidence-based approach

Hepatocellular carcinoma(HCC) makes up 75%-85% of all primary liver cancers and is the fourth most common cause of cancer related death worldwide. Chronic liver disease is the most significant risk factor for HCC with 80%-90% of new cases occurring in the background of cirrhosis. Studies have shown that early diagnosis of HCC through surveillance programs improve prognosis and availability of curative therapies. All patients with cirrhosis and high-risk hepatitis B patients are at risk for HCC and should undergo surveillance. The recommended surveillance modality is abdominal ultrasound(US) given that it is cost effective and noninvasive with good sensitivity. However, US is limited in obese patients and those with non-alcoholic fatty liver disease(NAFLD). With the current obesity epidemic and rise in the prevalence of NAFLD, abdominal computed tomography or magnetic resonance imaging may be indicated as the primary screening modality in these patients. The addition of alpha-fetoprotein to a surveillance regimen is thought to improve the sensitivity of HCC detection.Further investigation of serum biomarkers is needed. Semiannual screening is the suggested surveillance interval. Surveillance for HCC is underutilized and low adherence disproportionately affects certain demographics such as nonCaucasian race and low socioeconomic status.     

Liver Imaging Reporting and Data System criteria for the diagnosis of hepatocellular carcinoma in clinical practice: A pictorial minireview

Hepatocellular carcinoma (HCC) is the sixth most common cancer. The main risk factors associated with HCC development include hepatitis B virus, hepatitis C virus, alcohol consumption, aflatoxin B1, and nonalcoholic fatty liver disease. However, hepatocarcinogenesis is a complex multistep process. Various factors lead to hepatocyte malignant transformation and HCC development. Diagnosis and surveillance of HCC can be made with the use of liver ultrasound (US) every 6 mo. However, the sensitivity of this imaging method to detect HCC in a cirrhotic liver is limited, due to the abnormal liver parenchyma. Computed tomography (CT) and magnetic resonance imaging (MRI) are considered to be most useful tools for at-risk patients or patients with inadequate US. Liver biopsy is still used for diagnosis and prognosis of HCC in specific nodules that cannot be definitely characterized as HCC by imaging. Recently the American College of Radiology designed the Liver Imaging Reporting and Data System (LI-RADS), which is a comprehensive system for standardized interpretation of CT and MRI liver examinations that was first proposed in 2011. In 2018, it was integrated into the American Association for the Study of Liver Diseases guidance statement for HCC. LI-RADS is designed to ensure high sensitivity, precise categorization, and high positive predictive value for the diagnosis of HCC and is applied to “high-risk populations” according to specific criteria. Most importantly LI-RADS criteria achieved international collaboration and consensus among liver experts around the world on the best practices for caring for patients with or at risk for HCC.     

Long-term follow-up of HCV patients with sustained virological response after treatment with pegylated interferon plus ribavirin

Background: The progress of liver diseases may not stop after viral eradication. This study aimed to provide data on long-term prognosis of patients with hepatitis C virus(HCV) infection who underwent pegylated interferon plus ribavirin(PR) regimen and achieved a sustained virological response 24 weeks post-treatment(SVR24). Methods: Responders to the PR regimen in our hospital from January 2011 to June 2014 were enrolled and prospectively followed up. Baseline characteristics were profiled. The incidence of hepatocellular carcinoma(HCC), progression of liver disease(increase in liver stiffness or occurrence of decompensated complication), and HCV recurrence was all monitored. The accumulative and annualized incidence rates(AIRs) of these adverse events were analyzed, and the risk factors were also examined. Results: In total, 151 patients reached a median follow-up time of 103 weeks. Among them, two had an incidence of HCC during the surveillance with AIR of 0.68%(95% CI: 0.00-1.63%). Six patients showed progression of liver disease with AIR of 2.05%(95% CI: 0.42%-3.68%). Three patients who had risky behaviors encountered HCV reinfection. The cirrhotic patients faced higher risk of poor prognosis than non-cirrhotic patients, including HCC and progression of liver disease(AIR: 6.17% vs. 1.42%, P = 0.039). Conclusions: The incidence of HCC and progression of liver disease was evident in PR responders during the long-term follow-up period, but the risk level was low. Cirrhotic responders were more vulnerable to develop HCC post SVR24 compared with non-cirrhotic ones. HCV recurrence was rare in responders with SVR24 who had corrected their risky behaviors.     

Application of surveillance programs for hepatocellular carcinoma in the Asia–Pacific Region

Hepatocellular carcinoma (HCC) is a potential target for cancer surveillance (or screening) as it occurs in well-defined, at-risk populations and curative therapy is possible only for small tumors. Surveillance has been recommended by regional liver societies and is practiced widely, but its benefits are not clearly established. Hepatic ultrasonography with or without alpha fetoprotein (AFP) performed every 6 months is the preferred program. Surveillance of HCC has been well shown to detect small tumors for curative treatment, which may be translated to improved patient survival. However, most studies are limited by lead-time bias, length bias for early diagnosis of small HCC, different tumor growth rates and poor compliance with surveillance. Cost-effectiveness of surveillance programs depends on the rate of small HCC detected 'accidentally' (routine imaging) in a comparator group, annual incidence of HCC with various etiologies, patient age and the availability of liver transplantation. The incremental cost-effectiveness for 6-monthly AFP and ultrasound has been estimated from approximately $US26 000–74 000/quality adjusted life years (QALY). All cirrhotic patients are therefore recommended for HCC surveillance unless the disease is too advanced for any curative treatment. As chronic hepatitis B can develop into HCC without going through liver cirrhosis, high-risk non-cirrhotic chronic hepatitis B patients are also recommended for HCC surveillance. In conclusion, HCC surveillance could be effective at reducing disease-specific mortality with acceptable cost-effectiveness among selected patient groups, provided it is a well-organized program.     

Endoscopic ultrasound and fine needle aspiration for the diagnosis of hepatocellular carcinoma

Liver cancer is one of the most frequent solid cancers. The major risk factor associated with the development of hepatocellular carcinoma (HCC) is cirrhosis caused by hepatitis B, hepatitis C virus or chronic alcohol consumption. The overall prognosis of patients with HCC is very poor and this is mainly due to the advanced stages of cancer at presentation and also because of underlying cirrhosis. When HCC is diagnosed at early stages, prognosis is better with five-year disease free survival of around 50% with resection, or local ablative treatments such as radio-frequency ablation or percutaneous ethanol injection, and 70-80% with liver transplantation. Therefore, systematic screening of all the high-risk patients is the key to an early diagnosis of small HCC and the use of an appropriate treatment modality. The currently available tools for the screening, surveillance and diagnosis of HCC in the presence of cirrhosis remain sub-optimal. The advancements made in the past 10 years, however, have made HCC a potentially curable disease in a highly selected group of patients. This review will briefly discuss the current guidelines for surveillance and diagnosis of HCC in high-risk subjects and then review the potential role of endoscopic ultrasound and fine needle aspiration for the diagnosis of small HCC.     

Screening and interventions to prevent nonalcoholic fatty liver disease/nonalcoholic steatohepatitis-associated hepatocellular carcinoma

Liver cancer is the sixth most commonly diagnosed cancer worldwide, with hepatocellular carcinoma (HCC) comprising most cases. Besides hepatitis B and C viral infections, heavy alcohol use, and nonalcoholic steatohepatitis (NASH)-associated advanced fibrosis/cirrhosis, several other risk factors for HCC have been identified (i.e. old age, obesity, insulin resistance, type 2 diabetes). These might in fact partially explain the occurrence of HCC in non-cirrhotic patients without viral infection. HCC surveillance through effective screening programs is still an unmet need for many nonalcoholic fatty liver disease (NAFLD) patients, and identification of pre-cirrhotic individuals who progress to HCC represents a substantial challenge in clinical practice at the moment. Patients with NASH-cirrhosis should undergo systematic HCC surveillance, while this might be considered in patients with advanced fibrosis based on individual risk assessment. In this context, interventions that potentially prevent NAFLD/ NASH-associated HCC are needed. This paper provided an overview of evidence related to lifestyle changes (i.e. weight loss, physical exercise, adherence to healthy dietary patterns, intake of certain dietary components, etc.) and pharmacological interventions that might play a protective role by targeting the underlying causative factors and pathogenetic mechanisms. However, well-designed prospective studies specifically dedicated to NAFLD/NASH patients are still needed to clarify the relationship with HCC risk.     

Hepatocellular Carcinoma Surveillance in a Western Population with Hepatitis B

Hepatocellular carcinoma (HCC) is a malignant tumor arising primarily in cirrhotic livers as a consequence of chronic hepatitis B or C virus infection or alcohol-induced cirrhosis. Unlike the majority of other common cancer types, the incidence of HCC in the United States is still rising, with peak incidence expected for 2020. Although hepatitis B is a less common etiology for the development of HCC in the West, it is the most common risk factor among certain ethnic groups in the United States. Given the high case fatality of HCC, surveillance efforts have been recommended. Specifically, HCC surveillance has demonstrated a survival benefit in patients with chronic hepatitis B. In this review, we discuss the demographics of patients with HCC in the United States, the evidence promoting surveillance, and recent literature identifying the best surveillance test.