Hepatitis C prevalence in patients with hepatocellular carcinoma without cirrhosis. Am J Med Sci. 2010;339:169-173. [PMID: 20087166 DOI: 10.1097/maj.0b013e3181c4af27]

Current Imaging Diagnosis of Hepatocellular Carcinoma

Simple Summary

The role of imaging in the management of hepatocellular carcinoma (HCC) has significantly evolved and expanded beyond the plain radiological confirmation of the tumor based on the typical appearance in a multiphase contrast-enhanced CT or MRI examination. The introduction of hepatobiliary contrast agents has enabled the diagnosis of hepatocarcinogenesis at earlier stages, while the application of ultrasound contrast agents has drastically upgraded the role of ultrasound in the diagnostic algorithms. Newer quantitative techniques assessing blood perfusion on CT and MRI not only allow earlier diagnosis and confident differentiation from other lesions, but they also provide biomarkers for the evaluation of treatment response. As distinct HCC subtypes are identified, their correlation with specific imaging features holds great promise for estimating tumor aggressiveness and prognosis. This review presents the current role of imaging and underlines its critical role in the successful management of patients with HCC.

Abstract

Hepatocellular carcinoma (HCC) is the fourth leading cause of cancer related death worldwide. Radiology has traditionally played a central role in HCC management, ranging from screening of high-risk patients to non-invasive diagnosis, as well as the evaluation of treatment response and post-treatment follow-up. From liver ultrasonography with or without contrast to dynamic multiple phased CT and dynamic MRI with diffusion protocols, great progress has been achieved in the last decade. Throughout the last few years, pathological, biological, genetic, and immune-chemical analyses have revealed several tumoral subtypes with diverse biological behavior, highlighting the need for the re-evaluation of established radiological methods. Considering these changes, novel methods that provide functional and quantitative parameters in addition to morphological information are increasingly incorporated into modern diagnostic protocols for HCC. In this way, differential diagnosis became even more challenging throughout the last few years. Use of liver specific contrast agents, as well as CT/MRI perfusion techniques, seem to not only allow earlier detection and more accurate characterization of HCC lesions, but also make it possible to predict response to treatment and survival. Nevertheless, several limitations and technical considerations still exist. This review will describe and discuss all these imaging modalities and their advances in the imaging of HCC lesions in cirrhotic and non-cirrhotic livers. Sensitivity and specificity rates, method limitations, and technical considerations will be discussed.

Hepatocellular Carcinoma: Does the Background Liver With or Without Cirrhosis Matter?

OBJECTIVES

The pathologic differences between hepatocellular carcinoma (HCC) arising in noncirrhotic and cirrhotic livers have not been well studied.

METHODS

We performed a retrospective analysis of 378 HCC cases (95 in noncirrhotic, 283 in cirrhotic livers) from pathology archives (2010-2017).

RESULTS

Patients without cirrhosis were more likely to have hepatitis B (13.68% vs 2.83%, P < .001) or no known liver disease (30.53% vs 4.24%, P < .001), while hepatitis C was more common in patients with cirrhosis (65.72% vs 30.53%, P < .001). HCCs in noncirrhotic livers were larger in size (P < .001); were more likely to have a macrotrabecular histologic pattern (13.68% vs 4.95%, P < .01); were more likely to have fibrolamellar (3.16% vs 0%, P = .02), macrotrabecular-massive (13.68% vs 6.01%, P = .03), and clear cell (16.84% vs 6.71%, P < .01) subtypes; have a higher histologic grade (P < .01); be anaplastic tumor cells (P < .001); have a higher rate of vascular invasion (P < .01); and have a higher tumor stage (P = .04).

CONCLUSIONS

The findings indicate that HCCs in noncirrhotic livers demonstrate a larger tumor size; have a more macrotrabecular histologic pattern; have fibrolamellar, macrotrabecular-massive, and clear cell subtypes; have a higher tumor grade and stage; have a higher rate of vascular invasion; and have more anaplastic tumor cells compared with cirrhotic livers. Further studies to explore different pathways that promote oncogenesis in noncirrhotic livers are needed to better understand the pathogenesis of HCC.

Non-Cirrhotic Liver is Associated with Poor Prognosis of Hepatocellular Carcinoma: A Literature Review

Primary hepatocellular carcinoma (HCC) is the fifth most frequently reported malignancy, and it is also the second most common cause of cancer-related deaths worldwide. Although most HCC cases have been reported to develop from cirrhosis, accumulating data suggest that HCC is also closely related to non-cirrhotic chronic liver disease. Traditionally, HCC was thought to develop mostly from cirrhosis; however, an increasing number of reports have found that HCC can develop directly from inflammation without cirrhosis. The incidence of HCC in non-cirrhotic liver (HCC-NCL) is high, especially in developed countries. Studies have found that the most common cause of HCC-NCL is neglected fatty liver disease. This type of HCC has unique clinical characteristics and is closely related to metabolic disorders. Unfortunately, the prevention of HCC-NCL has not received enough attention worldwide, and there is also a lack of specific screening methods and clinical guidelines. This article mainly reviews the etiology, incidence, clinical characteristics, and screening markers of HCC-NCL to improve the understanding and prevention of this disease.

Hyperlipidemia and Nonalcoholic Steatohepatitis Predispose to Hepatocellular Carcinoma Development Without Cirrhosis

BACKGROUND

Hepatocellular carcinoma (HCC) accounts for 90% of primary hepatic malignancies. With the exception of chronic hepatitis B (CHB), other etiologies of chronic liver disease require progression to cirrhosis before HCC development. Case reports have described HCC in noncirrhotic patients with hepatitis C (HCV) and nonalcoholic fatty liver disease.

GOAL

The aim of this study was to determine the prevalence of patients without cirrhosis and CHB who developed HCC among a large cohort of HCC patients and to identify independent variables that are associated with no cirrhosis among patients with HCC.

STUDY

From 2005 to 2015, hepatobiliary cancer patients seen in our liver cancer and liver transplant clinics were evaluated. Patients were included if above18 years old and had histologically confirmed HCC from liver biopsy, resection specimen, or explanted livers. Patients with CHB, non-HCC tumors, or missing paired tumor and nontumor liver histology were excluded. Demographic information, pertinent laboratory values, and comorbid conditions were recorded. Potential predictors were evaluated using both backward stepwise logistic regression model and classification tree model.

RESULTS

Of the 1927 patients screened, 545 HCC patients (411 transplanted, 43 resected, 74 transarterial chemoembolization/radiofrequency ablation, 17 untreated) included, 29 (5.3%) patients had no cirrhosis histologically. Eleven patients had HCV, 3 had alcoholic liver disease, 3 had nonalcoholic fatty liver, and 12 had cryptogenic liver disease. Logistic regression models show that patients with hyperlipidemia and elevated serum alanine aminotransferase are more likely to develop HCC without cirrhosis (odds ratio, 1.73 and 0.40; P<0.05).

CONCLUSIONS

This large cohort, histology-confirmed case-controlled study shows that patients with nonalcoholic fatty liver disease and hyperlipidemia with elevated serum alanine aminotransferase (most likely nonalcoholic steatohepatitis) are significantly associated with the development of HCC in the absence of cirrhosis.

Practice, Knowledge, and Barriers for Screening of Hepatocellular Carcinoma Among High-Risk Chinese Patients

BACKGROUND

Hepatocellular carcinoma (HCC) is among the leading causes of cancer deaths in China. Considering its poor prognosis when diagnosed late, Chinese guidelines recommend biannual screening for HCC with abdominal ultrasound and serum α-fetoprotein (AFP) test for high-risk populations.

OBJECTIVES

To investigate the practice, knowledge, and self-perceived barriers for HCC screening among high-risk hospital patients in China.

METHODS

An interview-based questionnaire was conducted among Chinese patients with chronic hepatitis B and/or chronic hepatitis C infection from outpatient clinics at 2 tertiary medical institutions in Shanghai and Wuhan, China.

FINDINGS

Among 352 participating patients, 50.0% had routine screening, 23.3% had irregular screening, and 26.7% had incomplete or no screening. Significant determinants for screening included higher level of education, underlying liver cirrhosis, a family history of HCC, and better knowledge concerning viral hepatitis, HCC, and HCC screening guidelines. Moreover, factors associated with better knowledge were younger age, female gender, urban residency, education level of college or above, annual household income of greater than 150,000 RMB, and longer duration of hepatitis infection. The 3 most common barriers reported for not receiving screening were not aware that screening for HCC exists (41.5%), no symptoms or discomfort (38.3%), and lack of recommendation from physicians (31.9%).

CONLUSIONS

Health care professionals and community leaders should actively inform patients regarding the benefits of HCC screening through design of educational programs. Such interventions are expected to increase knowledge about HCC and HCC screening, as well as improve screening adherence and earlier diagnosis.

The Role of Direct-acting Antivirals in the Treatment of Children with Chronic Hepatitis C

In the United States, chronic infection with the hepatitis C virus (HCV) affects an estimated 0.1-2% of the pediatric population, who are consequently at risk for major complications, including cirrhosis, hepatocellular carcinoma, and death. The current standard of treatment for chronic hepatitis C (CHC) in children is pegylated-interferon-alpha (PEG-IFN) in combination with ribavirin. PEG-IFN/ribavirin therapy is approved for children ages 3 and older; however, it is often held from use until adulthood because of its extensive list of potential side effects and high likelihood of causing adverse symptoms. While CHC is usually indolent in children and adolescents, immediately treating and curbing the spread of HCV before adulthood is important, as there can be transmission to other individuals via sexual activity and infected females can later vertically transmit the infection during pregnancy, the latter representing the most common means of transmission for children in the United States. The recent development of direct-acting antivirals has shown promising results in clinical trials for use in children and has dramatically increased the rates of sustained virological response in adults while improving side effect profiles as compared to interferon-based treatments. Given the usually indolent course of CHC in children, significant side effects of the currently-approved PEG-IFN/ribavirin therapy, and likely availability of all-oral interferon-free regimens for children within a few years, deferring treatment in clinically-stable children with CHC in anticipation of upcoming superior treatment modalities may be justified.

Hepatocellular carcinoma in cirrhotic versus noncirrhotic livers: results from a large cohort in the Netherlands

OBJECTIVES

Hepatocellular carcinoma (HCC) usually occurs in patients with cirrhosis, but can also develop in noncirrhotic livers. In the present study we explored associated risk factors for HCC without cirrhosis and compared patient and tumor characteristics and outcomes in HCC patients with and without underlying cirrhosis.

METHODS

Patients with HCC diagnosed in the period 2005-2012 in five Dutch academic centers were evaluated. Patients were categorized according to the presence of cirrhosis on the basis of histology or combined radiological and laboratory features.

RESULTS

In total, 19% of the 1221 HCC patients had no underlying cirrhosis. Noncirrhotic HCC patients were more likely to be female and to have nonalcoholic fatty liver disease or no risk factors for underlying liver disease, and less likely to have hepatitis C virus or alcohol-related liver disease than did cirrhotic HCC patients. HCCs in noncirrhotic livers were more often unifocal (67 vs. 48%), but tumor size was significantly larger (8 vs. 4 cm). Despite the larger tumors, more patients underwent resection (50 vs. 10%) and overall survival was significantly better than in cirrhotics. In multivariate analyses, absence of cirrhosis [hazard ratio (HR) 0.49, 95% confidence interval (CI) 0.38-0.63] and presence of hepatitis B (HR 0.68, 95% CI 0.51-0.91) were independent predictors for lower mortality, whereas hepatitis C virus was associated with higher mortality (HR 1.32, 95% CI 1.01-1.65).

CONCLUSION

HCC without cirrhosis was strongly associated with female sex and presence of nonalcoholic fatty liver disease or no risk factors for underlying liver disease. In absence of cirrhosis, resections were more often performed, with better survival despite larger tumor size.

Lower incidence of hepatocellular carcinoma and cirrhosis in hepatitis C patients with sustained virological response by pegylated interferon and ribavirin

BACKGROUND

To elucidate the benefits of successful antiviral therapy in chronic hepatitis C (CHC) patients

METHODS

A total of 463 CHC patients who underwent pegylated interferon alfa and ribavirin therapy were classified as sustained virological response (SVR) or non-SVR based on response to antiviral therapy. We investigated disease progression to cirrhosis in non-cirrhotic patients, development of cirrhosis-related complications such as ascites, variceal bleeding, and hepatic encephalopathy in patients with cirrhosis, and development of hepatocellular carcinoma (HCC).

RESULTS

Three hundred patients achieved SVR, and 163 were classified into the non-SVR group. The overall SVR rates were 64.8 %, and multivariate analysis showed that younger age, non-cirrhosis, HCV genotype 2 or 3, lower HCV RNA level (<800,000 IU/mL), and lower body weight were independent factors associated with SVR (all P < 0.05). During a median follow-up of 36.1 months, non-cirrhotic patients with SVR had significantly lower risk of progression to cirrhosis compared with patients with non-SVR (P < 0.001). Moreover, SVR was related to a reduced risk of HCC development (P = 0.017).

CONCLUSIONS

SVR resulted in significantly more favorable long-term outcomes, such as lower risk of progression to cirrhosis and HCC occurrence compared with non-SVR.

Obesity-associated mechanisms of hepatocarcinogenesis

Obesity has been recognized as a key component of the metabolic syndrome, a cluster of risk factors associated with diabetes and cardiovascular morbidity. In addition, obesity has been linked to higher frequency of cancers in a variety of tissues including the liver. Liver cancer most often occurs as hepatocellular carcinoma (HCC) complicating cirrhosis due to chronic viral infection or toxic injury and remains the third leading cause of cancer death in the world. However, HCC is increasingly diagnosed among individuals with obesity and related disorders. As these metabolic conditions have become globally prevalent, they coexist with well-established risk factors of HCC and create a unique challenge for the liver as a chronically diseased organ. Obesity-associated HCC has recently been attributed to molecular mechanisms such as chronic inflammation due to adipose tissue remodeling and pro-inflammatory adipokine secretion, ectopic lipid accumulation and lipotoxicity, altered gut microbiota, and disrupted senescence in stellate cells, as well as insulin resistance leading to increased levels of insulin and insulin-like growth factors. These mechanisms synergize with those occurring in chronic liver disease resulting from other etiologies and accelerate the development of HCC before or after the onset of cirrhosis. Increasingly common interactions between oncogenic pathways linked to obesity and chronic liver disease may explain why HCC is one of the few malignancies with rising incidence in developed countries. Better understanding of this complex process will improve our strategies of cancer prevention, prediction, and surveillance.

Burden of pediatric hepatitis C

Hepatitis C virus (HCV) is a major health burden infecting 170-210 million people worldwide. Additional 3-4 millions are newly-infected annually. Prevalence of pediatric infection varies from 0.05%-0.36% in the United States and Europe; up to 1.8%-5.8% in some developing countries. The highest prevalence occurs in Egypt, sub-Saharan Africa, Amazon basin and Mongolia. HCV has been present in some populations for several centuries, notably genotypes 1 and 2 in West Africa. Parenteral anti-schistosomal therapy practiced in the 1960s until the early 1980s had spread HCV infection throughout Egypt. Parenteral acquisition of HCV remains a major route for infection among Egyptian children. Insufficient screening of transfusions, unsterilized injection equipment and re-used needles and syringes continue to be major routes of HCV transmission in developing countries, whereas vertical transmission and adolescent high-risk behaviors (e.g., injection drug abuse) are the major routes in developed countries. The risk of vertical transmission from an infected mother to her unborn/newborn infant is approximately 5%. Early stages of HCV infection in children do not lead to marked impairment in the quality of life nor to cognitive, behavioral or emotional dysfunction; however, caregiver stress and family system strain may occur. HCV slowly progresses to serious complications as cirrhosis (1%-2%) and hepatocellular carcinoma (HCC) especially in the presence of risk factors as hemolytic anemias, obesity, treated malignancy, and concomitant human immune deficiency and/or hepatitis B virus co-infection. HCV vaccine remains elusive to date. Understanding the immune mechanisms in patients who successfully cleared the infection is essential for vaccine development. The pediatric standard of care treatment consists of pegylated interferon-α 2a or b plus ribavirin for 24-48 wk. The new oral direct acting antivirals, approved for adults, need further evaluation in children. Sustained virologic response varies depending on the viral load, genotype, duration of infection, degree of aminotransferase elevation, adiposity and single nucleotide polymorphisms of interleukin (IL)-28B locus. The goals of treatment in individual patients are virus eradication, prevention of cirrhosis and HCC, and removing stigmatization; meanwhile the overall goal is decreasing the global burden of HCV. IL-28B polymorphisms have been also associated with spontaneous clearance of vertically acquired HCV infection. The worldwide economic burden of HCV for children, families and countries is estimated to be hundreds of millions of US dollars per year. The United States, alone, is estimated to spend 199-336 million dollars in screening, monitoring and treatment during one decade. The emotional burden of having an HCV infected child in a family is more difficult to estimate.

Neuroimmunomodulation in human autoimmune liver disease

Bidirectional interaction between immune and nervous systems is considered an important biological process in health and disease. However, little is known about the mechanisms involved in their interaction in the human liver. This study examines the distribution of intrahepatic NPY, SP immunoreactive (IR) nerve fibers and their antomical relationship with immunocells containing tumor necrosis factor-α (TNF-α) and nuclear factor κB (NF-κB) in patients with autoimmune hepatitis. Liver specimens were obtained from control liver and autoimmune hepatitis patients. The immunoreactivity was determined by immunohisto- and immunocytochemistry and confocal laser microscopy. In hepatitis, the number of NPY-IR and SP-IR nerve fibers increased significantly. These IR nerve fibers were in very close contact with the lymphocytes. In healthy controls, no NPY-IR, SP-IR or NF-κB IR lymphocytes and only a few TNF-α positive cells, were observed. In hepatitis, some of the lymphocytes showed immunoreactivity for SP and NPY in the portal area. Fluorescent double-labeled immunostaining revealed that in these cells NPY did not colocalize with TNF-α or NF-κB. However, some of the SP fluorescence-positive immune cells exhibited immunostaining for p65 of NF-κB, where their labeling was detected in the nuclei. Under the electronmicroscope, these cells could be identified (lymphocytes, plasmacells and mast cells). The gap between the IR nerve fibers and immunocells was 1 μm or even less. Overexpression of SP in lymphocytes may amplify local inflammation, while NPY may contribute to liver homeostasis in hepatitis. Neural immunomodulation (SP antagonists and NPY) might be a novel therapeutic concept in the management of liver inflammation.

Surgical resection for hepatocellular carcinoma in the noncirrhotic: the Western experience

Although hepatocellular carcinoma (HCC) is most often a sequela of severe hepatic fibrosis or cirrhosis, a proportion of cases arise in the noncirrhotic patient. The gold standard therapy in such cases is surgical resection. Innovations in operative technique allow for this treatment to be implemented with very low mortality and acceptable morbidity at high-volume hepatobiliary centers. This chapter discusses various etiologies of noncirrhotic HCC and presents a large single-center experience that is compared to other Western series.

Imaging of hepatocellular carcinoma: current concepts

Hepatocellular carcinoma (HCC) is the most common primary hepatic malignancy, and usually develops in the setting of liver cirrhosis. The early diagnosis of HCC is essential as curative treatment (including surgical resection and liver transplantation) improves survival. While screening and surveillance are traditionally performed with ultrasound, reported accuracies of ultrasound vary greatly, and poor sensitivity for small nodules is a uniformly recognized concern. Advances in computed tomography (CT) and magnetic resonance imaging (MRI), including multidetector technology and fast breath hold sequences now allow dynamic multiphasic enhanced imaging of the liver with excellent spatial and temporal resolution, holding much promise for improved HCC detection.

Hepatitis C virus-associated primary hepatocellular carcinoma in non-cirrhotic patients

BACKGROUND

There is limited literature on hepatocellular carcinoma (HCC) in patients with chronic hepatitis C virus (HCV) infection in the absence of cirrhosis.

AIMS

To investigate the relationship between HCV and HCC in the absence of cirrhosis and to characterize patients with HCV infection presenting with HCC in the absence of cirrhosis.

METHODS

We identified all adult patients with histological confirmation of HCC between 1994 and 2007 (404 patients). A case-control design (four controls for each case with non-cirrhotic HCC) was chosen to compare characteristics and survival of HCV in HCC patients without (cases) and with (controls) cirrhosis. Conditional logistic regression analysis was used to identify factors independently associated with HCV in non-cirrhotic HCC.

RESULTS

Eighty-seven patients with non-cirrhotic HCC were identified, six (7 %) had HCV infection in comparison with 107 of 317 (55.7 %) with cirrhotic HCC (P < 0.001). Compared with the HCV-associated HCC cirrhotic group, patients with HCV-associated HCC in the absence of cirrhosis were more likely to present with a single nodule (100 vs. 66.7 %), larger nodule size (>5 cm) (100 vs. 16.7 %), and macrovascular invasion (66.7 vs. 17.4 %) at time of diagnosis. Four of six patients with HCV-associated HCC in the absence of cirrhosis where alive at three years (all had resection), which was better survival than for HCC arising in cirrhotic livers of HCV-infected individuals (66.7 vs. 39.1 %).

CONCLUSION

We found that HCV is responsible for a small minority of non-cirrhotic HCC cases representing an uncommon and poorly defined subgroup of HCC.

NASPGHAN practice guidelines: Diagnosis and management of hepatitis C infection in infants, children, and adolescents

Hepatitis C virus (HCV) is an RNA virus that affects >180 million individuals worldwide with a high propensity for chronic infection. Children with HCV infection differ from adults in several ways including some modes of transmission, rates of clearance, progression of fibrosis, and the duration of potential chronic infection when acquired at birth. Since the discovery of HCV in 1989, there have been significant advances in the understanding of the virology and natural history of chronic HCV infection in children. In addition, there are now several treatment options for children with chronic hepatitis C infection and many new therapies on the horizon. As a consequence, the North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition brought together experts in pediatric hepatology to review the available data in children and provide clinicians with approaches to the diagnosis, management, and prevention of HCV infection in children and adolescents. The guideline details the epidemiology and natural history of HCV infection in children, the diagnostic workup, monitoring and treatment of disease, and provides an update on future treatment options and areas of research.

Impact of HCV genetic differences on pathobiology of disease

Multiple HCV genotypes have been isolated worldwide. Genotype seems to be involved in the main pathological aspects of HCV infection. Insulin resistance, steatosis and progression toward cirrhosis, fibrosis and hepatocellular carcinoma establish and develop following genotype-specific mechanisms. Moreover genotype influences pharmacological treatment in term of dose and duration. Pathways involved in cell proliferation, apoptosis, lipid metabolism, insulin and interferon signaling are impaired to a different extent among genotypes, leading to distinct pathological settings. Genotype 1 is associated with a more aggressive disease with increased insulin resistance, worst response to therapy, higher risk of cirrhosis and hepatocellular carcinoma development, while genotype 3 is associated with increased steatosis and fibrosis. The identification and characterization of HCV types and subtypes provides insight into the different outcome of HCV infection and responsiveness to therapy. In the present article, we focused on the pathogenicity of HCV genotypes and their effect on disease progression and treatment.

Screening of autoantibodies as potential biomarkers for hepatocellular carcinoma by using T7 phase display system

BACKGROUND

Hepatocellular carcinoma (HCC) is one of the most common tumors worldwide. Autoantibodies to tumor-associated proteins in the serum profile, as new biomarkers, may improve the early detection of HCC.

METHODS

In this study, we interrogated a HCC cDNA T7 phage library for tumor-associated proteins using biopan enrichment techniques with HCC patient and normal sera. The enrichment of tumor-associated proteins after biopanning was tested using plaque assay and immunochemical detection. The putative tumor-associated phage clones were collected for PCR and sequencing analysis. Identities of those selected sequences were revealed through the sequence BLAST program. The identified phage-expressed proteins were then used to develop phage protein ELISA to measure matching autoantibodies using 70 HCC patients, 50 chronic hepatitis patients, and 70 normal serum samples. The logistic regression model and leave-one-out validation were used to evaluate predictive accuracies with a single marker as well as with combined markers.

RESULTS

Twenty-six phage-displayed proteins have sequence identity with known or putative tumor-associated proteins. Immunochemical reactivity of patient sera with phage-expressed proteins showed that the autoantibodies to phage-expressed protein CENPF, DDX3, HSPA4, HSPA5, VIM, LMNB1, and TP53 had statistical significance in HCC patients. Measurements of the seven autoantibodies combined in a logistic regression model showed that combined measurements of these autoantibodies was more predictive of disease than any single antibody alone, underscoring the importance of identifying multiple potential markers.

CONCLUSION

Autoantibody in the serum profiling is a promising approach for early detection and diagnosis of HCC. The panel of autoantibodies appears preferable to achieve superior accuracy rather than an autoantibody alone, and may have significant relevance to tumor biology, novel drug development, and immunotherapies.

Hepatitis B and C virus hepatocarcinogenesis: lessons learned and future challenges

Worldwide, hepatocellular carcinoma (HCC) is one of the most common cancers. It is thought that 80% of hepatocellular carcinomas are linked to chronic infections with the hepatitis B (HBV) or hepatitis C (HCV) viruses. Chronic HBV and HCV infections can alter hepatocyte physiology in similar ways and may utilize similar mechanisms to influence the development of HCC. There has been significant progress towards understanding the molecular biology of HBV and HCV and identifying the cellular signal transduction pathways that are altered by HBV and HCV infections. Although the precise molecular mechanisms that link HBV and HCV infections to the development of HCC are not entirely understood, there is considerable evidence that both inflammatory responses to infections with these viruses, and associated destruction and regeneration of hepatocytes, as well as activities of HBV- or HCV-encoded proteins, contribute to hepatocyte transformation. In this review, we summarize progress in defining mechanisms that may link HBV and HCV infections to the development of HCC, discuss the challenges of directly defining the processes that underlie HBV- and HCV-associated HCC, and describe areas that remain to be explored.

The role of oncogenic viruses in the pathogenesis of hepatocellular carcinoma

HBV and HCV have major roles in hepatocarcinogenesis. More than 500 million people are infected with hepatitis viruses and, therefore, HCC is highly prevalent, especially in those countries endemic for HBV and HCV. Viral and host factors contribute to the development of HCC. The main viral factors include the circulating load of HBV DNA or HCV RNA and specific genotypes. Various mechanisms are involved in the host-viral interactions that lead to HCC development, among which are genetic instability, self-sufficiency in growth signals, insensitivity to antigrowth signals, evasion of apoptosis, limitless replicative potential, sustained angiogenesis, and tissue invasiveness. Prevention of HBV by vaccination, as well as antiviral therapy against HBV and for HCV seem able to inhibit the development of HCC.

Molecular pathology of hepatic neoplasms: classification and clinical significance

Recent technological advances have enabled investigators to characterize the molecular genetics and genomics of hepatic neoplasia in remarkable detail. From these studies, an increasing number of molecular markers are being identified that correlate with clinically important tumor phenotypes. This paper discusses current knowledge relevant to the molecular classification of epithelial primary hepatic tumors that arise in adults, including focal nodular hyperplasia (FNH), hepatocellular adenoma (HCA), hepatocellular carcinoma (HCC), cholangiocarcinoma (CC), and combined HCC-CC. Genetic analysis has defined molecular subtypes of HCA that are clinicopathologically distinct and can be distinguished through immunohistochemistry. Gene expression studies have identified molecular signatures of progression from dysplastic nodules (DNs) to early HCC in cirrhosis. Analyses of the mutational spectra, chromosomal aberrations and instability, transcriptomics, and microRNA profiles of HCC have revealed the existence of biologically distinct subtypes of this common malignancy, with prognostic implications. Molecular characterization of biliary and hepatic progenitor cell phenotypes in liver cancer has shed new light on the histogenesis of these tumors and has focused attention on novel therapeutic targets. In coming years, the molecular classification of hepatic neoplasms will be increasingly valuable for guiding patient care, as targeted therapies for liver cancer are developed and brought into clinical practice.

MR imaging of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a common malignancy typically associated with chronic liver disease and is a leading cause of mortality among these patients. Prognosis is improved when detected early. MRI is the best imaging examination for accurate diagnosis. Although arterial enhancement with delayed washout, increased T2-weighted signal intensity, delayed capsular enhancement, restricted diffusion, and tumor thrombus are typical features, not all lesions demonstrate these findings. The radiologist must be familiar with these typical imaging characteristics, and less common appearances and associated findings of HCC, and must be able to differentiate them from those of lesions that mimic HCC. Knowledge of therapeutic options and how those are related to imaging findings is imperative to assist clinicians in managing these patients.

[Hepatitis C virus infection and hepatocarcinogenesis]

It is evidenced that both HBV and HCV infections may cause chronic hepatitis, liver cirrhosis and hepatocellular carcinoma (HCC). HCV is considered as an oncogen virus. The mechanism of carcinogenesis in case of the two distinct viruses shows a number of common and different features. HCC usually develops in stage of liver cirrhosis caused by chronic inflammation of many years or decades. In contrast to HBC, HCV will not be incorporated into the genome of hepatocytes. It induces throughout different mechanisms the development of cancer cells, which will proliferate out of control. Before the discovery of HCV, the connection of non-A non-B (NANB) hepatitis and liver cancer has yet been observed. The subsequent epidemiological studies confirmed this association. A number of publications prove that HCC may develop without cirrhosis in HCV infected patients. The exact mechanism is not known, but data indicate that some proteins of the virus may induce oncogenic process. Differences were found in HCV core gene between HCC patients with and without cirrhosis. It is postulated that the virus evolves its oncogenic effect via endoplasmic and oxidative stress, further on by activation of different oncogenic signal pathways. Recent publications indicate the role of virus induced insulin resistance. Besides the virus determined factors, the host reaction, the deficient tumor cell eliminating capacity may also have a role in the development of liver carcinoma. Monitoring of HCV infected patients for HCC is an important clinical issue. Most relevant is the regular ultrasound cheek up. Serum alpha fetoprotein level is elevated only in a smaller proportion of the patients. The treatment protocol of HCV induced HCC does not differ from the others developed in non-HCV liver diseases.

Oncogenic potential of hepatitis C virus proteins

Chronic hepatitis C virus (HCV) infection is a major risk factor for liver disease progression, and may lead to cirrhosis and hepatocellular carcinoma (HCC). The HCV genome contains a single-stranded positive sense RNA with a cytoplasmic lifecycle. HCV proteins interact with many host-cell factors and are involved in a wide range of activities, including cell cycle regulation, transcriptional regulation, cell proliferation, apoptosis, lipid metabolism, and cell growth promotion. Increasing experimental evidences suggest that HCV contributes to HCC by modulating pathways that may promote malignant transformation of hepatocytes. At least four of the 10 HCV gene products, namely core, NS3, NS5A and NS5B play roles in several potentially oncogenic pathways. Induction of both endoplasmic reticulum (ER) stress and oxidative stress by HCV proteins may also contribute to hepatocyte growth promotion. The current review identifies important functions of the viral proteins connecting HCV infections and potential for development of HCC. However, most of the putative transforming potentials of the HCV proteins have been defined in artificial cellular systems, and need to be established relevant to infection and disease models. The new insight into the mechanisms for HCV mediated disease progression may offer novel therapeutic targets for one of the most devastating human malignancies in the world today.

Diagnostic value of glypican-3 in serum and liver for primary hepatocellular carcinoma

AIM: To evaluate the diagnostic value of glypican-3 (GPC3) in serum and liver for primary hepatocellular carcinoma (HCC).

METHODS: Serum levels of GPC3 and α-fetoprotein (AFP) were measured in 75 patients with primary HCC and 32 patients with liver cirrhosis. Expression of GPC3 and AFP in 58 HCC and 12 cirrhotic specimens was detected with immunohistochemical staining.

RESULTS: When the cut-off value of serum GPC3 was set at 300 ng/L, its sensitivity and specificity for HCC were 47.0% and 93.5%, respectively. Among the 14 patients with HCC at stage according to the Barcelona Clinic Liver Cancer staging system, the serum GPC3 level was higher than 300 ng/L in 50% (7/14) patients, the serum AFP level was not ≥ 400 μg/L in any patient. Combined serum AFP and GPC3 significantly increased the sensitivity to the diagnosis of HCC. The GPC3 expression was detected in cytoplasm of HCC cells but not in hepatocytes and bile ducts of benign tumors. Among the 58 HCC patients, the GPC3 was expressed in 100% (28/28) patients with their serum AFP level ≥ 400 μg/L, and in 90% (27/30) patients with their AFP level < 400 μg/L, respectively. The GPC3 was weakly or negatively expressed in all paracarcinomatous and cirrhotic tissue samples. AFP positive HCC cells were only found in 1 out of the 58 HCC patients.

CONCLUSION: GPC3 protein is a sensitive and specific serum marker for diagnosis of early HCC. Its expression in liver tissues can be used to discriminate tumor cells from benign hepatic cells.