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.     

Surveillance for hepatocellular carcinoma in chronic viral hepatitis: Is it time to personalize it?

Surveillance with abdominal ultrasound with or without alpha-fetoprotein is recommended by clinical practice guidelines for patients who are considered to be at risk of developing hepatocellular carcinoma (HCC), including those with cirrhosis, advanced fibrosis and special subgroups of chronic hepatitis B (CHB). Application of the standard surveillance strategy to all patients with chronic liver disease (CLD) with or without cirrhosis imposes major sustainability and economic burdens on healthcare systems. Thus, a number of HCC risk scores were constructed, mainly from Asian cohorts, to stratify the HCC prediction in patients with CHB. Similarly, even if less than for CHB, a few scoring systems were developed for chronic hepatitis C patients or cirrhotic patients with CLD of different etiologies. Recently, a few newsworthy HCC-risk algorithms were developed for patients with cirrhosis using the combination of serologic HCC markers and clinical parameters. Overall, the HCC risk stratification appears at hand by several validated multiple score systems, but their optimal performance is obtained only in populations who show highly homogenous clinic-pathologic, epidemiologic, etiologic and therapeutic characteristics and this limitation poses a major drawback to their sustainable use in clinical practice. A better understanding of the dynamic process driving the progression from CLD to HCC derived from studies based on molecular approaches and genetics, epigenetics and liquid biopsy will enable the identification of new biomarkers to define the individual risk of HCC in the near future, with the possibility to achieve a real and cost/effective personalization of surveillance.     

Risk prediction of hepatitis B virus-related hepatocellular carcinoma in the era of antiviral therapy

Hepatocellular carcinoma(HCC)is a grave primary liver cancer that has a limited therapeutic option because it is generally diagnosed later in an advanced stage due to its aggressive biologic behavior.The early detection of HCC has a great impact on the treatment efficacy and survival of patients at high risk for cancer.Potential host,environmental,and virus-related risk factors have been introduced.Hepatitis B virus(HBV)is a major cause of end-stage liver diseases such as liver cirrhosis or HCC in endemic areas,and its serologic or virologic status is considered an important risk factor.HCC risk prediction derived from the identification of major risk factors is necessary for providing adequate screening/surveillance strategies to high-risk individuals.Several risk prediction models for HBV-related HCC have been presented recently with simple,efficient,and readily available to use parameters applicable to average-or unknown-risk populations as well as high-risk individuals.Predictive scoring systems of risk estimation to assess HCC development can provide the way to an evidence-based clinical approach for cost-and effort-effective outcomes,capable of inducing a personalized surveillance program according to risk stratification.In this review,the concepts and perspectives of the risk prediction of HCC are discussed through the analysis of several risk prediction models of HBV-related HCC.     

WJG 20th Anniversary Special Issues（1）: Hepatocellular carcinoma Risk prediction of hepatitis B virus-related hepatocellular carcinoma in the era of antiviral therapy

Chronic hepatitis B(CHB)-related hepatocellular carcinoma(HCC)is a major health problem in AsianPacific regions.Antiviral therapy reduces,but does not eliminate the risk of HCC.It would be a heavy financial burden in most low and middle economic countries if all CHB patients received antiviral therapy and HCC surveillance.Thus,there is a need for accurate risk prediction to assist prognostication,decisions on the need for antiviral therapy and HCC surveillance.A few wellestablished risk factors for HCC,namely advanced age,male gender,high viral load,cirrhosis etc.,are the core components of three HCC risk scores:CU-HCC,GAGHCC and REACH-B scores.These 3 scores were confirmed to be accurate in predicting HCC up to 10 years in treatment-na ve patients.Their validity and applicability have recently been demonstrated in a large cohort of entecavir treatment patients.A decrease in risk scores after antiviral therapy translates to a lower risk of HCC.These findings support the application of HCC risk scores in all CHB patients.Different levels of care and different intensities of HCC surveillance should be offered according to the risk profile of patients.Patients at risk of HCC should undergo regular HCC surveillance,even when they are receiving antiviral treatment.     

First multicenter study for risk factors for hepatocellular carcinoma development in North Africa

AIM:To assess the role of the major risk factors for hepatocellular carcinoma(HCC) development in the western part of North Africa.METHODS:A multicenter case control study was conducted in Tunisia,Morocco and Algeria in collaboration with Pasteur Institutes in these countries.A total of 164 patients with HCC and 250 control subjects without hepatic diseases were included.Prevalences of HBsAg,anti-hepatitis C virus(HCV)and diabetes were assessed.HCV and HBV genotyping were performed for anti-HCV and HBsAg positive patients.RESULTS:The mean age of patients was 62±10 years old for a 1.5 M:F sex ratio.Sixty percent of HCC patients were positive for anti-HCV and 17.9% for HBsAg.Diabetes was detected in 18% of cases.Odd ratio(OR)and 95% confidence intervals(CI) were 32.0(15.8-65.0),7.2(3.2-16.1) and 8.0(3.1 -20.0)for anti-HCV,HBsAg and diabetes respectively.Multivariate analysis indicated that the three studied factors were independent.1b HCV genotype and D HBV genotype were predominant in HCC patients.HCV was the only risk factor significantly associated with an excess of cirrhosis(90% vs 68% for all other risk factors collectively,P=0.00168).Excessive alcohol consumption was reliably established for 19(17.6%) cases among the 108 HCC patients for whom data is available.CONCLUSION:HCV and HBV infections and diabetes are the main determinants of HCC development in North Africa.An active surveillance and secondary prevention programs for patients with chronic hepatitis and nutrition-associated metabolic liver diseases are the most important steps to reduce the risk of HCC in the region.Salah Berkane,Department of Gastroenterology BologhineUniversity Hospital,Bologhine 16090,Algiers,Algeria     

Hepatocellular carcinoma risk after viral response in hepatitis C virus-advanced fibrosis: Who to screen and for how long?

Hepatitis C virus (HCV) chronic infection is associated with fibrosis progression, end-stage liver complications and HCC. Not surprisingly, HCV infection is a leading cause of liver-related morbidity and mortality worldwide. After sustained virological response (SVR), the risk of developing hepatocellular carcinoma is not completely eliminated in patients with established cirrhosis or with advanced fibrosis. Therefore, lifelong surveillance is currently recommended. This strategy is likely not universally cost-effective and harmless, considering that not all patients with advanced fibrosis have the same risk of developing HCC. Factors related to the severity of liver disease and its potential to improve after SVR, the molecular and epigenetic changes that occur during infection and other associated comorbidities might account for different risk levels and are likely essential for identifying patients who would benefit from screening programs after SVR. Efforts to develop predictive models and risk calculators, biomarkers and genetic panels and even deep learning models to estimate the individual risk of HCC have been made in the direct-acting antiviral agents era, when thousands of patients with advanced fibrosis and cirrhosis have reached SVR. These tools could help to identify patients with very low HCC risk in whom surveillance might not be justified. In this review, factors affecting the probability of HCC development after SVR, the benefits and risks of surveillance, suggested strategies to estimate individualized HCC risk and the current evidence to recommend lifelong surveillance are discussed.     

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.     

Surveillance for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) appears mainly in patients with underlying liver disease and it is recognized as one of the most important causes of death in this population. Early detection by surveillance has been suggested as an effective tool for reducing cancer-specific mortality and the most accepted strategy is semiannual abdominal ultrasound in those patients at risk of HCC development. The benefit of HCC surveillance is proven by a randomized-controlled study, several prospective or retrospective analyses, and multiple modeling studies and according to the current scientific evidence, surveillance of HCC should be recommended and widely implemented. Major efforts should be done for improving the diagnostic accuracy of the screening tools and for better identifying those patients at risk of HCC development in whom a surveillance program would be cost-effective.     

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.     

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.     

Anticarcinogenic impact of interferon therapy on the progression of hepatocellular carcinoma in patients with chronic viral infection

Hepatocellular carcinoma (HCC) is mainly caused by a persistent infection due to the hepatitis B or hepatitis C virus. The number of HCC cases is increasing in Asian and African countries, as well as in European and American countries. Interferon (IFN) therapy, used for type B chronic liver diseases, inhibits hepatic carcinogenesis in patients with compensated cirrhosis. However, there is insufficient evidence that IFN therapy inhibits hepatic carcinogenesis in patients with chronic hepatitis B. There are few cases of HCC due to chronic hepatitis B, and long-term follow-up periods verifying the inhibitory effect of IFN on hepatic carcinogenesis have not been obtained. To improve the prognosis of type B chronic liver diseases, it is important that hepatitis treatment follows guidelines in which a patient's age and the extent of hepatic fibrosis are taken into account. As for chronic hepatitis C, since a sustained virological response (SVR) in IFN therapy inhibits hepatic carcinogenesis and improves prognosis, treatment that aims for an SVR while taking into consideration host-sided and virus-sided factors is recommended for patients with type C chronic liver diseases. In areas with low incidence of HCC (e.g. USA), a large number of cases and a long-term follow-up period are needed before it can be accepted that IFN therapy inhibits hepatic carcinogenesis. After locally curative treatment of HCC, IFN therapy suppresses recurrence and improves survival rates.     

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.     

Hepatitis B viral load affects prognosis of hepatocellular carcinoma

Hepatocellular carcinoma(HCC)is a complex disease that is dually challenging to treat due to underlying chronic liver disease in addition to the cancer itself.The prognosis of patients with HCC is determined by intrahepatic tumor status and reserved hepatic function.Hepatitis B virus(HBV)is an established major risk factor of HCC development,and HBV viral load is being increasingly recognized as a prognostic factor in the presence of established HCC.High HBV viral load may affect the prognosis of HBV-related HCC patients in several ways.First,it is associated with more frequent recurrence of HBV-related HCC after treatment.Second,it is associated with more occurrence and severity of potentially life-threatening HBV reactivation.Last,it is associated with more worsened liver function,which limits the therapeutic options for HBV-related HCC.HBV,directly or indirectly,can induce hepatocarcinogenesis.In patients with a high HBV DNA level and subsequent active hepatitis,adhesion molecules expressed on the sinusoidal cells are up-regulated and may increase intrahepatic metastasis.HCC progression after treatment can lead to a poor prognosis by reducing number of normal functioning hepatocytes.Thus,high HBV viral load can affect the prognosis of patientswith HCC by frequent recurrence after treatment for HCC and deterioration of hepatic function associated with HCC progression.Recent meta-analysis showed that antiviral treatment reduces HCC recurrence and liver-related mortality after curative therapy of HCC.Given the strong relationship between high HBV DNA load and poor survival outcome of HCC patients due to cancer progression,it is expected that long-term antiviral therapy results in the sustained HBV suppression,control of inflammation,reduction in HCC progression,and eventually in improved overall survival.     

Anti-viral therapy to reduce recurrence and improve survival in hepatitis B virus-related hepatocellular carcinoma

Hepatocellular carcinoma(HCC)is the most common malignancy and the third leading cause of cancer death worldwide.Chronic infection with hepatitis B virus(HBV)and hepatitis C virus accounts for approximately75%-80%of HCC cases worldwide.In particular,chronic HBV infection is a predominant risk factor for HCC in Asia and Africa.Hepatic resection and radiofrequency ablation are increasingly used for the curative treatment of HCC,and good local control can be achieved.However,the high rate of recurrence is a major obstacle to improving prognosis.A high viral load of HBV DNA is the most important correctable risk factor for recurrence.Furthermore,interferon and/or nucleotide analogues may decrease HBV DNA.Therefore,these drugs may decrease recurrence.In this article,treatment strategies for HBV-related HCC are described in order to reduce recurrence and improve survival.     

Cost-effectiveness of liver cancer screening

Screening for primary liver cancer means surveillance for hepatocellular carcinoma (HCC), which is one of the most common cancers worldwide. Detection of HCC for curative treatment is increased by surveillance, but target population, optimal periodicity and cost-effectiveness aspects are still debated issues. The aim of surveillance is to obtain a reduction in HCC-related mortality and this is usually achieved through an early diagnosis that increases both applicability and cost-effectiveness of curative treatments. The aim of the present review is to analyse economic aspects of HCC surveillance. Articles that assessed cost-effectiveness of surveillance for HCC, published between 1996 and February 2013, were reviewed in order to verify the cost-effectiveness of surveillance, its optimal periodicity, the target population and the role of alternative surveillance strategies. International guidelines are currently based on the results of such cost-effectiveness analyses, highlighting the importance of the release of cost-effectiveness-guided guidelines for HCC management.     

慢性乙型肝炎病毒感染者肝细胞癌筛查和监测

肝细胞癌是我国常见恶性肿瘤,疾病负担十分沉重。筛查和监测是提高肝细胞癌患者早诊早治和生存率的有效措施。慢性乙型肝炎病毒感染是我国肝细胞癌的主要病因,有必要制定专门的筛查和监测策略。中国肝炎防治基金会组织国内有关专家,参考国内外相关指南,并结合当前研究进展和临床实践经验共同讨论后达成一致意见,旨在为规范开展慢性乙型肝炎病毒感染者肝细胞癌的筛查和监测提供参考,进而改善我国肝细胞癌的防控效果和患者预后。     

Hepatocellular carcinoma in developing countries: Prevention, diagnosis and treatment

Hepatocellular carcinoma(HCC)occurs commonly and with increasing frequency in developing countries,where it also carries an especially grave prognosis.The major risk factor for HCC in these regions is chronic hepatitis B virus(HBV)infection,although dietary exposure to aflatoxin B1 also plays an important etio-logical role.Prevention of HCC in developing regions is unlikely in the foreseeable future.Although an effec-tive vaccine against HBV is available,the percentage of babies born in developing countries that receive the full course of immunization remains low.Moreover,the usually long interval between infection with HBV and the development of HCC means that 30 to 50 years will elapse before the full effect of the vaccine will be realized.Practical measures to prevent aflatoxin B1 ex-posure are not in place.Serumα-fetoprotein levels are a useful pointer to the diagnosis of HCC in low-income countries,but definitive diagnosis is hampered both by the lack of the sophisticated imaging equipment now available in developed countries and by obstacles to obtaining histological proof.In the majority of patients in low-income regions,the tumor is inoperable by the time the patient presents.Hepatic resection is seldom possible in sub-Saharan Africa,although the tumor is successfully resected in a larger number of patients in China.Liver transplantation for HCC is rarely performed in either region.Sophisticated new radiotherapy tech-niques are not available in developing countries.The beneficial effects of the multikinase inhibitor,sorafenib,are encouraging,although financial considerations may restrict its use in low-income countries.     

Prevention of hepatocellular carcinoma in the Asia–Pacific region: Consensus statements

Among approximately 650 000 people who die from hepatocellular carcinoma (HCC) each year, at least two‐thirds live in Asia. Efforts to improve early diagnosis and treatment have not yet impacted mortality. An Asia–Pacific Working Party convened in Hong Kong in June 2008 to consider ways to prevent HCC in this region. Separate reviews have summarized epidemiology of HCC, preventive approaches related to hepatitis B virus (HBV), hepatitis C virus (HCV) and non‐viral liver diseases, and the role of surveillance to detect HCC at a curative stage. We now present Consensus Statements from these deliberations and reviews. As chronic hepatitis B is the most common cause of HCC in Asia, effective hepatitis B vaccination programs are the most important strategy to reduce HCC incidence. Prevention of HCV by screening blood donors, universal precautions against blood contamination in health‐care settings and reducing HCV transmission from injection drug use are also vital. There is strong evidence that effective antiviral therapy to control HBV infection or eradicate HCV substantially reduces (but does not abolish) HCC risk. With hemochromatosis, family screening, early diagnosis and correcting iron overload to prevent liver fibrosis prevents HCC. There is currently insufficient evidence to give firm recommendations on alcohol, obesity/metabolic risk factors and other liver diseases. HCC surveillance for high‐risk groups is recommended in individual cases but cost‐effectiveness is not as high as infant hepatitis B vaccination and screening blood for HCV. Widespread application of HCC surveillance in Asia–Pacific countries depends on economic factors and health‐care priorities.     

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.