Epidemiology of liver cancer in Europe.

Liver cancer (LC) ranks fifth in frequency in the world, with an estimated 437,000 new cases in 1990. The estimates are different when LC frequency is analyzed by sex and geographical areas. In developed areas, the estimates are 53,879 among men and 26,939 among women. In developing areas, the estimates are 262,043 in men and 93, 961 in women. Areas of highest rates include Eastern and South Eastern Asia, Japan, Africa and the Pacific Islands (LC age-adjusted incidence rates [AAIRs] ranging from 17.6 to 34.8). Intermediate rates (LC AAIRs from 4.7 to 8.9 among men) are found in Southern, Eastern and Western Europe, Central America, Western Asia and Northern Africa. Low rates are found among men in Northern Europe, America, Canada, South Central Asia, Australia and New Zealand (LC AAIRs range from 2.7 to 3.2). In Europe, an excess of LC incidence among men compared with women is observed, and the age peak of the male excess is around 60 to 70 years of age. Significant variations in LC incidence among different countries have been described and suggest differences in exposure to risk factors. Chronic infection with the hepatitis B virus (HBV) and hepatitis C virus (HCV) in the etiology of LC is well established. In Europe, 28% of LC cases have been attributed to chronic HBV infection and 21% to HCV infection. Other risk factors such as alcohol consumption, cigarette smoking and oral contraceptives may explain the residual variation within countries. Interactions among these risk factors have been postulated. New laboratory techniques and biological markers such as polymerase chain reaction detection of HBV DNA and HCV RNA, as well as specific mutations related to LC, may help to provide quantitative estimates of the risk related to each these factors.     

Chronic liver diseases as liver tumor precursors

Liver cancer is a major global health problem and hepatocellular carcinoma (HCC) accounts for 75% of all liver carcinoma. HCC occurs more often in men than in women and mostly in people 50 to 60 years old. The disease is more common in parts of sub-Saharan Africa and Asia than in North and South America and Europe. Nevertheless its incidence increased over the past 4 decades in some Western countries. Worldwide, liver carcinoma is the 5th most common cancer and 3rd most common cause of cancer mortality (behind only lung and colorectal cancer) with approximately 680,000 annual deaths. Unlike most of the other malignancies, HCC almost entirely develops in the context of inflammation and organ injury and is related to cirrhosis in about 85% of the cases. Among underlying etiologies of liver cirrhosis, most frequent are viral infection and toxic substances, mostly alcohol. The main HCC risk factor in Eastern Asia and Africa is hepatitis B virus infection. Hepatitis C virus infection is the main risk factor in Western countries. Hereditary hemochromatosis is not a very frequent cause of liver cirrhosis, but these patients are at higher risk for HCC compared with other etiologies of cirrhosis. Aflatoxins, cancer-causing substances made by a type of plant mold, can play a role in some countries in Asia and Africa, and can have a synergistic effect with hepatitis B infection.     

The role of the hepatitis viruses in cholangiocarcinoma

Cholangiocarcinoma is the second most common liver cancer in the world. The aetiology of the disease is diverse incorporating a variety of conditions leading to biliary stasis, biliary and liver inflammation, but a large number of cases still occur in the absence of established risk factors. Its incidence and mortality is increasing, which has intensified the search for alternative aetiological agents and pathogenetic mechanisms. Chronic infection with hepatitis B and hepatitis C viruses are the primary risk factor for hepatocellular cancer. This review focuses on the epidemiological evidence of a role for these viruses in cholangiocarcinoma and the pathogenetic mechanisms that might be involved.     

Time trends in incidence and mortality for chronic liver disease and liver cancer in the interval 1980-1997 in Catalonia, Spain

BACKGROUND AND AIMS: It has been reported that the incidence of liver cancer and intrahepatic bile duct tumours might be increasing in some developed countries. The purpose of this study was to examine time trends of incidence and mortality rates of liver cirrhosis and liver cancer for the period 1980-1997 in Catalonia, Spain. METHODS: Data were obtained from the Catalan Mortality Registry and the Tarragona Cancer Registry. Joinpoint analysis was used to detect time-related changes in incidence and mortality of liver diseases. The cohort effect on mortality and incidence rates was explored by an age-period-cohort model. RESULTS: Mortality from liver cirrhosis decreased during the study period for both sexes and all age groups, with the exception of men aged between 25 and 35 years. No changes in incidence or mortality rates were observed for liver cancer. Mortality rates for intrahepatic bile duct tumours increased in men and women, while incidence rates remained stable. CONCLUSIONS: This study identified in Catalonia an increase in mortality due to liver cirrhosis among 25-35-year-old men. Mortality rates for intrahepatic bile duct tumours increased for all age groups and both sexes. The former could be related to hepatitis C or B viruses and human immunodeficiency virus co-infection, while the latter remains unexplained.     

Prevention of hepatocellular carcinoma: a concise review of contemporary issues

Hepatocellular carcinoma (HCC) is the fifth most common cancer and the second leading cause of cancer deaths in men. Due to differences in the prevalence of viral hepatitis, the incidence of HCC in low and middle income countries is much higher than that of high income countries. Strategies to limit the impact of HCC include primary prevention against new cases of viral hepatitis, secondary prevention of HCC in susceptible individuals, and early HCC detection. Universal hepatitis B vaccination has resulted in dramatic reduction in incident cases of chronic hepatitis B and HCC in children and adolescents, and the full effect is expected in the next 20 years. The key hurdle for universal vaccination is the cost and the accessibility in low and middle income countries. Randomized controlled trials and meta-analyses showed that successful treatment of chronic hepatitis B and C can reduce the risk of HCC and cirrhotic complications. HCC surveillance by regular ultrasound examination and alpha fetoprotein testing leads to early cancer detection and offers the opportunity for curative treatment. Since all these measures are costly and require manpower and infrastructure support, the implementation should rely on the liaison among healthcare providers and policymakers. The cost-effectiveness of various strategies should also be studied based on local situations.     

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.     

Family history of liver cancer and hepatocellular carcinoma

Familial clustering of hepatocellular carcinoma (HCC) has been frequently reported in eastern Asiatic countries, where hepatitis B infection is common. Little is known about the relationship between family history of liver cancer and HCC in Western populations. We carried out a case-control study in Italy, involving 229 HCC cases and 431 hospital controls. Data on family history were summarized through a binary indicator (yes/no) and a family history score (FHscore), considering selected family characteristics. Odds ratios (ORs) and the corresponding 95% confidence intervals (CIs) were obtained from unconditional multiple logistic regression models, including terms for age, sex, study center, education, tobacco smoking, alcohol drinking, hepatitis B surface antigen, and/or anti-hepatitis C virus positivity. We also performed a meta-analysis on family history of liver cancer and liver cancer updated to April 2011 using random-effects models. After adjustment for chronic infection with hepatitis B/C viruses, family history of liver cancer was associated with HCC risk, when using both the binary indicator (OR, 2.38; 95% CI, 1.01-5.58) and the FHscore, with increasing ORs for successive score categories. Compared to subjects without family history and no chronic infection with hepatitis B/C viruses, the OR for those exposed to both risk factors was 72.48 (95% CI, 21.92-239.73). In the meta-analysis, based on nine case-control and four cohort studies, for a total of approximately 3,600 liver cancer cases, the pooled relative risk for family history of liver cancer was 2.50 (95% CI, 2.06-3.03). CONCLUSION: A family history of liver cancer increases HCC risk, independently of hepatitis. The combination of family history of liver cancer and hepatitis B/C serum markers is associated with an over 70-fold elevated HCC risk.     

The influence of alcohol consumption and hepatitis B and C infections on the risk of liver cancer in Europe

BACKGROUND/AIMS: To assess the variability of liver cancer (LC) risk associated with hepatitis B (HBV) and hepatitis C (HCV) viruses and alcohol intake in 2002 throughout Europe. METHODS: Incidence data were obtained from population-based cancer registries whereas mortality, HBV, HCV and alcohol exposures were obtained from the WHO databases. Relative risk of LC and their posterior probabilities to be >1 were obtained and plotted in maps through a Bayesian random effects model. RESULTS: HBV prevalence >2% increased the risk of developing LC a 15% in men and 21% in women; HCV prevalence >2%, 54% in men and 33% in women and, pure alcohol intake >11l, 26% and 14%, respectively (all of them statistically significant). These risk factors played a similar role in the risk of dying from LC among men, whereas HBV and alcohol were not statistically significant among women. Significant high LC risk, after HBV/HCV and alcohol adjustment were observed for both sexes in: Hungary, Moldova, Romania, Croatia, Greece, Italy, Spain, France and Austria. CONCLUSIONS: South-North and East-West decreasing gradients for LC risk were observed in Europe. HBV, alcohol and, mainly, HCV are independent risk factors that could explain this geographical pattern.     

Infections and cancer: established associations and new hypotheses

Around the world, infection is one of the most important causes of cancer. Almost one in every five malignancies can be attributed to infectious agents. Among infection-related neoplasms, cancers of the stomach, liver and cervix uteri detain the highest incidence figures, and are known to be largely attributable to Helicobacter pylori, hepatitis B and C viruses, and human papilloma virus, respectively. Other infectious organisms can also cause cancer; these include the Epstein-Barr virus (nasopharyngeal carcinoma, and different types of lymphoma), Human herpes virus-8 (Kaposi's Sarcoma), human T-cell leukemia virus type I (leukaemia, lymphoma), liver flukes (cholangiocarcinoma) and schistosomiasis (bladder cancer). Infection with human immunodeficiency virus, although strongly associated with an excess of cancer incidence at many cancer sites, is probably not carcinogenic per se, but acts mainly via immunodeficiency. The burden of infection-related cancers is still underestimated worldwide, due to the use of conservative population prevalence and risk ratio estimates. Furthermore, associations with new infectious agents remain yet to be explored.     

Non-viral factors contributing to hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a major cause of cancer death worldwide, accounting for over half a million deaths per year. The geographic pattern of HCC incidence is parallel to exposure to viral etiologic factors. Its incidence is increasing, ranging between 3% and 9% annually depending on the geographical location, and variability in the incidence rates correspond closely to the prevalence and pattern of the primary etiologic factors. Chronic infections with hepatitis B viruses or hepatitis C viruses have both been recognized as human liver carcinogens with a combined attributable fraction of at least 75% of all HCC cases. Multiple non-viral factors have been implicated in the development of HCC. Increased body mass index and diabetes with subsequent development of non-alcoholic steatohepatitis represent significant risk factors for HCC. Other non-viral causes of HCC include iron overload syndromes, alcohol use, tobacco, oral contraceptive, aflatoxin, pesticides exposure and betel quid chewing, a prevalent habit in the developing world. Wilson disease, α-₁ antitrypsin deficiency, Porphyrias, autoimmune hepatitis, Schistosoma japonicum associated with positive hepatitis B surface antigen, and thorotrast-ray are also contributing hepatocellualar carcinoma. In addition, primary biliary cirrhosis, congestive liver disease and family history of liver cancer increase the risk of HCC incident. In conclusion, clarification of relevant non-viral causes of HCC will help to focus clinicians on those risk factors that are modifiable. The multilevel preventative approach will hopefully lead to a reduction in incidence of non-viral HCC, and a decrease in the patient morbidity and mortality as well as the societal economic burden associated with HCC.     

Epidemiology and natural history of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a major contributor to cancer incidence and mortality. There is a wide variation, however, in the global distribution of HCC. Eighty percent of the burden is borne by countries in Asia and sub-Saharan Africa. In most high-risk countries, principal risk factors include infection with hepatitis B virus and dietary exposure to aflatoxin B(1). In contrast, hepatitis C virus and alcohol consumption are more important risk factors in low-risk countries. In recent years, the incidence of HCC has decreased in some high-risk countries and increased in some low-risk countries. Reasons for both trends are not completely understood, but are likely related to public health efforts in Asia and the increase in hepatitis C virus infection in low-risk countries. Vaccination programs against hepatitis B virus will likely decrease the HCC rate even further in decades to come.     

Incidence of parenchymal liver diseases in Denmark, 1981 to 1985: analysis of hospitalization registry data. The Danish Association for the Study of the Liver

The sex-specific and age-specific incidence rates of the major parenchymal liver diseases in a North European population were estimated using a computerized registry of all admissions to somatic hospitals in Denmark. The incidence was calculated by counting all incident cases of these diseases reported to the registry in the 5-yr period 1981 to 1985 and dividing the number of cases by the number of person-years at risk in this period. The incidence rates (per million person-years) were for men and women, respectively: infectious hepatitis, 109 and 71; toxic hepatitis, 19 and 22; chronic hepatitis, 27 and 29; alcoholic cirrhosis, 190 and 85; nonalcoholic nonbiliary cirrhosis, 110 and 82; primary biliary cirrhosis, 4 and 14. The pattern of the age-specific incidence rates was similar in men and women in infectious hepatitis, alcoholic cirrhosis, nonalcoholic nonbiliary cirrhosis and primary biliary cirrhosis. Toxic and chronic hepatitis had a higher incidence in women than in men only in older age groups. The incidence of idiopathic hemochromatosis, Wilson's disease, secondary biliary cirrhosis, portal vein thrombosis and Budd-Chiari's syndrome were less than four in both sexes.     

Non-viral causes of hepatocellular carcinoma

Hepatocellular carcinoma(HCC) is the most common primary liver malignancy and represents an international public health concern as one of the most deadly cancers worldwide.The main etiology of HCC is chronic infection with hepatitis B and hepatitis C viruses.However,there are other important factors that contribute to the international burden of HCC.Among these are obesity,diabetes,non-alcoholic steatohepatitis and dietary exposures.Emerging evidence suggests that the etiology of many cases of HCC is in fac...     

Risk factors for the rising rates of primary liver cancer in the United States

BACKGROUND: A recent increase in the incidence of hepatocellular carcinoma was reported in the United States. The cause of this witnessed rise remains unknown. METHODS: We examined the temporal changes in both age-specific and age-standardized hospitalization rates of primary liver cancer associated with hepatitis C, hepatitis B, and alcoholic cirrhosis in the Department of Veterans Affairs Medical Center's Patient Treatment File. RESULTS: A total of 1605 patients were diagnosed with primary liver cancer between 1993 and 1998. The overall age-adjusted proportional hospitalization rate for primary liver cancer increased from 36.4 per 100,000 (95% confidence interval [CI], 34.0-38.9) between 1993 and 1995 to 47.5 per 100,000 (95% CI, 44.6-50.1) between 1996 and 1998. There was a 3-fold increase in the age-adjusted rates for primary liver cancer associated with hepatitis C virus, from 2.3 per 100,000 (95% CI, 1. 8-3.0) between 1993 and 1995 to 7.0 per 100,000 (95% CI, 5.9-8.1) between 1996 and 1998. Concomitant with this rise, the age-specific rates for primary liver cancer associated with hepatitis C also shifted toward younger patients. During the same periods, the age-adjusted rates for primary liver cancer associated with either hepatitis B virus (2.2 vs 3.1 per 100,000) or alcoholic cirrhosis (8. 4 vs 9.1 per 100,000) remained stable. The rates for primary liver cancer without risk factors also remained without a statistically significant change, from 17.5 (95% CI, 15.8-19.1) between 1993 and 1995 to 19.0 per 100,000 (95% CI, 17.3-20.7) between 1996 and 1998. CONCLUSIONS: Hepatitis C virus infection accounts for most of the increase in the number of cases of primary liver cancer among US veterans. The rates of primary liver cancer associated with alcoholic cirrhosis and hepatitis B virus infection have remained stable. Arch Intern Med. 2000;160:3227-3230.     

Chronic hepatitis B virus infection in the Asia-Pacific region and Africa: review of disease progression

Countries in the the Asia-Pacific region and Africa tend to have the highest prevalence of hepatitis B infection worldwide. Hepatitis B infection progresses from an asymptomatic persistently infected status to chronic hepatitis B, cirrhosis, decompensated liver disease and/or hepatocellular carcinoma. The aim of this review was to summarize rates and risk factors for progression between disease states in the Asia-Pacific region and Africa. A literature search was conducted employing MEDLINE and EMBASE (1975-2003) using the following key words: hepatitis B, natural history, disease progression, cirrhosis, hepatocellular carcinoma, mortality, Africa and the Asia-Pacific region. Bibliographies of articles reviewed were also searched. Ranges for annual progression rates were: (i) asymptomatic persistent infection to chronic hepatitis B, 0.84-2.7%; (ii) chronic hepatitis B to cirrhosis, 1.0-2.4%; and (iii) cirrhosis to hepatocellular carcinoma, 3.0-6.6%. Patients with asymptomatic persistent infection and chronic hepatitis B had relatively low 5-year mortality rates (<4%); rates (>50%) were much higher in patients with decompensated liver disease and hepatocellular carcinoma. No data were found for progression rates in African populations. Hepatitis B e antigen was a risk factor for chronic hepatitis B, and bridging hepatic necrosis in chronic hepatitis B increased the risk of cirrhosis. Risk factors for hepatocellular carcinoma included cirrhosis, co-infection with hepatitis C virus, and genetic and environmental factors. In this review, wide ranges of disease progression estimates are documented, emphasizing the need for further studies, particularly in Africa, where progression rates are largely not available. Summarizing information on factors associated with disease progression should assist in focusing efforts to arrest the disease process in those at most risk.     

The impact of the hepatitis B mass immunisation campaign on the incidence and risk factors of acute hepatitis B in Italy

BACKGROUND/AIMS: This study aimed to evaluate the impact of the campaign for hepatitis B mass immunisation of children and teenagers, introduced in 1991, on the incidence of and risk factors for hepatitis B in Italy. METHODS: Hepatitis B cases reported to the surveillance system for type-specific acute viral hepatitis (SEIEVA) during the period 1987-1997 were used to estimate incidence. To assess the association between potential risk factors and hepatitis B cases, hepatitis A cases generated by the same surveillance system were used as controls. RESULTS: During the period 1987-1997, 8275 acute hepatitis B cases were reported to SEIEVA. Hepatitis B incidence declined from 10.4/100,000 in 1987 to 2.9/100,000 in 1997. The fall was more evident before than after the introduction of compulsory vaccination against hepatitis B. The results of multivariate analysis showed that during the years 1995-1997, blood transfusion, intravenous drug use, surgical intervention, dental therapy, other parenteral exposures, multiple sexual partners, and being in the household of a chronic HBsAg carrier were all exposures independently associated with hepatitis B. CONCLUSIONS: The strong association linking acute hepatitis B with iatrogenic exposures, which are more common in adults, suggests that the present immunisation strategy should be combined with the implementation of non-immunologic preventive measures.     

Epidemiology of hepatocellular carcinoma.

Although rare in Canada and the United States, hepatocellular carcinoma (HCC) ranks as the eighth most common cancer in the world. High-risk regions are East and Southeast Asia, and sub-Saharan Africa. Independent of race and geography, rates in men are at least two to three times those in women; this sex ratio is more pronounced in high-risk regions. Rates of HCC in the United States have increased by 70% over the past two decades. Registry data in Canada and Western Europe show similar trends. In contrast, the incidence of HCC in Singapore and Shanghai, China, both high-risk regions, has declined steadily over the past two decades. Among white and black Americans, there is an inverse relationship between social class status and HCC incidence. Chronic infection by the hepatitis B virus (HBV) is by far the most important risk factor for HCC in humans. It is estimated that 80% of HCC worldwide is etiologically associated with HBV. In the United States, although the infection rate in the general population is low, HBV is estimated to account for one in four cases of HCC among non-Asians. Chronic infection by the hepatitis C virus is another important risk factor for HCC in the United States; however, this virus is believed to play a relatively minor role in the development of HCC in Africa and Asia. Dietary aflatoxin exposure is an important codeterminant of HCC risk in Africa and parts of Asia. In Canada and the United States, excessive alcohol intake, cigarette smoking and oral contraceptive use in women also are risk factors for HCC.     

The evolving epidemiology of hepatocellular carcinoma: a global perspective

Primary liver cancer, the majority of which are hepatocellular carcinomas, is now the second leading cause of cancer death worldwide. Hepatocellular carcinoma is a unique cancer that typically arises in the setting of chronic liver disease at a rate dependent upon the complex interplay between the host, disease and environmental factors. Infection with chronic hepatitis B or C virus is currently the dominant risk factor worldwide. However, changing lifestyle and environmental factors in western countries plus rising neonatal hepatitis B vaccination rates and decreasing exposure to dietary aflatoxins in developing countries are driving an evolution of the epidemiology of this cancer. An understanding of this change is crucial in combating the rising incidence currently being seen in western regions and will underpin the efforts to reduce the mortality rates associated with this cancer.     

Hepatotoxicity of rifampin and isoniazid. Is it all drug-induced hepatitis?

Serologic markers for hepatitis viruses were studied in 40 children who developed acute hepatitis during antituberculosis therapy with rifampin and isoniazid, with the aim of assessing the contributory role of these viruses toward producing hepatic injury. Hepatitis A and B were confirmed in 7.5 and 35% patients, respectively, by IgM antibodies. Epidemiologic evidence suggested the possibility of non-A, non-B hepatitis in at least a few of the remaining 23 children. Hepatitis B was seen more often in children with severe tubercular disease (72%) and was largely (92.8%) parenterally transmitted. The study highlights that the endemicity of viral hepatitis in developing countries, among other factors, could also be responsible for the reported higher incidence of hepatotoxicity from developing countries and also for the increased risk of hepatotoxicity seen in severe tubercular disease.     

Higher elimination rate of hepatitis C virus among women

SUMMARY. The mortality rate from liver disease in H town of the Fukuoka prefecture in Japan is significantly higher in men than in women. To clarify the gender-related difference, we evaluated subjects with hepatitis B virus (HBV) and hepatitis C virus (HCV) infection in the S area of this town. A total of 824 adults participated in this study, 332 men and 492 women. The incidence of positivity for hepatitis B surface antigen (HBsAg) in serum did not differ significantly between the subjects in the S area (1.9%) and Japanese blood donors (1.5%); however, the incidence of positivity for serum antibody to hepatitis C virus (HCVAb) in the subjects (31.8%) greatly exceeded that in Japanese blood donors (1.3%). The rate of positivity for HCVAb did not differ significantly between men (28.3%) and women (34.1%), but the proportion of serum HCV RNA-positive to HCVAb-positive subjects was significantly higher in men (78.2% in men vs 67.3% in women). The incidence of elevated serum alanine aminotransferase (ALT) in subjects positive for serum HCV RNA was also significantly higher in men (77.0% in men vs 55.8% in women). These results suggest that a more frequent elimination of HCV from serum in women may explain the observed lower mortality from liver disease.