Minor role of hepatitis B and C virus infection in the etiology of hepatocellular carcinoma in a low-endemic area

Different Etiological Entities of Liver Cancer Across Populations: Implications From Age-Period-Cohort Analysis on Incidence Trends

INTRODUCTION

The incidence of liver cancer has shown different temporal trends across populations, while the underlying reasons remain unclear.

METHODS

We examined temporal trends in the incidence of liver cancer in Hong Kong, Sweden, and the United States since the 1970s through 2021 using joinpoint regression and age-period-cohort analysis.

RESULTS

The age-standardized incidence rate of liver cancer in Hong Kong steadily decreased (average annual percentage change [AAPC] -2.2%, 95% confidence interval [CI] -2.8% to -1.7% in men; AAPC -2.1%, 95% CI -3.1% to -1.1% in women) in 1983-2020. The rate in Sweden increased on average by 0.8% (95% CI 0.2%-1.4%) per year in men and was stable in women (AAPC 0.2%, 95% CI -0.9%-1.4%) in 1970-2021. The rate in the United States increased by 2.1% (95% CI 1.5%-2.8%) per year in men and by 2.1% (95% CI 1.6%-2.5%) in women in 1975-2020, but decreasing trends were noted in 2015-2020 (AAPC -6.6%, 95% CI -8.3% to -4.9% in men; AAPC -4.2%, 95% CI -7.5% to -0.8% in women). Stratified analysis by histological type showed such decrease in recent years was limited to hepatocellular carcinoma, rather than intrahepatic cholangiocarcinoma. We observed distinct changes in trends across age groups and different trends across birth cohorts.

DISCUSSION

The incidence of liver cancer has decreased in Hong Kong but increased in Sweden and in the United States since the 1980s, despite the decreasing incidence in the United States since 2015. Such disparities may be explained by different etiology and implementation of preventive measures across populations.

Recognition criteria for occupational cancers in relation to hepatitis B virus and hepatitis C virus in Korea

The goal of this study was to review the scientific basis for the recognition of occupational cancer, in relation to hepatitis viral infections in Korea. Most Hepatitis B virus (HBV) infections in Korea occur as vertical infections, but these are decreasing rapidly due to vaccination. Hepatitis C virus (HCV) is known to be transmitted through parenteral routes, but the transmission route is often unclear. Most occupational infections of hepatitis virus involve accidental injuries of medical institution workers while using virus-contaminated medical devices. Many cohort studies and case-control studies have consistently reported that HBV and HCV infection increases the risk of hepatocellular carcinoma (HCC) and the strength of this association is high. Non-Hodgkin’s lymphoma appears to be associated with HCV. Cholangiocarcinoma, pancreatic cancer, leukemia, and thyroid cancer are considered to be less related or unrelated to epidemiological causation. There are no uniform international specific criteria for occupational cancer caused through occupational exposure to a hepatitis virus. In establishing appropriate standards applicable to Korea, there should be sufficient consideration of latency, virus exposure levels and frequency, and other cancers, apart from HCC.

In conclusion, we recommend keeping the current specific criteria. However, if a worker is injured at work when using a sharp medical device, and HBV and HCV viral infections are confirmed through serologic tests; if the worker is diagnosed as having a chronic HBV or HCV infection, a subsequent HCC (or Non-Hodgkin’s lymphoma following chronic HCV infection) can then be considered highly related to the worker’s occupation.

Alcohol consumption and recurrence of non-B or non-C hepatocellular carcinoma after hepatectomy: a propensity score analysis

BACKGROUND

The aim of this study was to identify factors related to the recurrence of non-B or non-C (NBNC) hepatocellular carcinoma (HCC).

STUDY DESIGN

Between April 2000 and March 2012, out of 621 consecutive HCC patients at our institution, 543 who underwent initial hepatectomy and had no extrahepatic metastases were enrolled in the study. Multivariate analysis were performed to identify risk factors for poor disease-free survival (DFS).

RESULTS

The 5-year DFS rate of NBNC (34 %) was better than that of hepatitis virus B (30 %, P = 0.011) and hepatitis virus C (21 %, P < 0.0001), significantly. Multivariate analysis revealed NBNC [hazard ratio (HR), 0.5; 95 % CI, 0.4-0.8; P < 0.0001)] to be an independent factor for DFS rate. We constructed a propensity score matching model with the 543 patients, and the 5-year DFS rates with and without severe alcohol liver disease (ALD) were 31.6 and 47.5 %, respectively (P = 0.013). In the 163 NBNC patients, severe ALD, mild ALD, and no ALD were seen in 35, 56, and 72 patients, respectively. Multivariate analysis revealed a vascular invasion into the hepatic vein (HR, 3.3; 95 % CI, 1.7-6.3; P < 0.0001) and severe ALD (HR, 2.0; 95 % CI, 1.1-3.6; P = 0.020) to be independent risk factors for poor DFS. By propensity score matching between mild and severe ALD, the 5-year DFS rates with severe and mild ALD were 26 and 50 %, respectively (P = 0.035).

CONCLUSIONS

The prognoses of NBNC patients were better than those of patients with viral infections. Among the NBNC patients, preoperative excessive alcohol intake decreased DFS rate of HCC occurrence after surgery.

Overweight and hypertriglyceridemia are risk factors for liver cirrhosis in middle-aged Swedish men

OBJECTIVE

Hyperlipidemia, overweight, insulin resistance and hypertension are associated with non-alcoholic fatty liver disease. The knowledge about these conditions as etiologic factors in liver cirrhosis is, however, limited. In this study, we examined the relation between overweight and hypertriglyceridemia, and development of liver cirrhosis in a general population.

MATERIAL AND METHODS

An epidemiological, longitudinal study was conducted involving men at the age of 50 with 40 years of follow-up. Baseline data were collected in 1963 and 1967. Cases of liver cirrhosis were identified by searching the Swedish Hospital Discharge Register and death certificates of the Central Bureau of Statistics. The independent effect of BMI, triglyceride levels and alcohol habits for cirrhosis of the liver was calculated by using multiple logistic regression analysis.

RESULTS

Elevated BMI and triglycerides were significant independent risk factors for the development of liver cirrhosis (OR 1.27 and 1.99, respectively, p < 0.01).

CONCLUSIONS

Overweight and hypertriglyceridemia are independent risk factors for liver cirrhosis in Swedish men.

[Surgical treatment of liver cancer: experience of the A Coruña UHC (Spain)]

INTRODUCTION

Liver cancer (LC) is one of the most frequent tumours, in which the potentially curative treatment is surgery: partial surgical resection or liver transplant.

OBJECTIVES

To determine the morbidity and mortality, survival, and their associated factors in patients with LC, according to the type of surgical treatment: partial surgical resection or liver transplant.

MATERIAL AND METHODS

A retrospective, observational follow-up study of LC patients diagnosed and treated from June 1994 to December 2007. A descriptive analysis of the variables was performed, as well as a Kaplan- Meier survival analysis and Cox regression.

RESULTS

The incidence of tumour recurrence in the 150 transplant patients was 13.3%, with a survival at 1, 3, and 5 years of 89.3%, 73.1% and 61.4%, respectively. The multivariate analysis showed that only the histological grade/differentiation was an independent risk factor. In the 33 patients with partial surgical resection, the incidence of tumour was 51.5%, with a survival at 1, 3, and 5 years of 90.9%, 60.2%, and 38.6%, respectively. A significantly higher mortality was observed in patients with higher tumour and TNM staging.

CONCLUSIONS

The survival throughout follow-up was higher in liver transplant, and tumour recurrence was more frequent in patients with partial surgical resection. The survival results in transplanted patients are consistent with the Spanish and European Liver Transplant Register and with the United Network for Organ Sharing register.

Prognostic and developmental factors in patients receiving liver transplant due to hepatocellular carcinoma: one center's experience in the north of Spain

BACKGROUND

Hepatocellular carcinoma (HCC) is one of the most frequent types of tumor. The aim of this study was to determine the survival of patients who had received liver transplants as a result of the disease.

METHODS

This observational follow-up study included 150 patients who received liver transplantations from June 1994 to December 2007. The study considered epidemiological and staging variables, tumor descriptions, and follow-up variables. We employed Kaplan-Meier methodology together with a Cox multivariate regression analysis.

RESULTS

The incidence of tumor relapse was 13.3%, with survival rates at 1, 3, and 5 years of 89.3%, 73.1%, and 61.4%, respectively. Variables that showed an independent effect to predict mortality were the degree of histological differentiation and of macrovascular invasion. Patients with poorly differentiated HCC had a 4.03 fold (95% confidence interval [CI]: 1.61-10.06) greater possibility of dying. Macrovascular involvement increased the risk of death (relative risk = 2.23), an effect that was at the limit of significance (95% CI 0.99-5.04).

CONCLUSIONS

The survival rate was consistent with the literature. Poor tumor differentiation and macrovascular involvement were independent predictors of mortality.

DNA of Helicobacter spp. and common gut bacteria in primary liver carcinoma

BACKGROUND AND AIM

Gastric and enteric Helicobacter species have been associated with the pathogenesis of some extragastric diseases.

METHODS

We retrospectively investigated the presence of DNA of Helicobacter species in samples of the cancer and the surrounding tumour-free liver tissues of patients with hepatocellular carcinoma (HCC, n=12) and cholangiocarcinoma (CC, n=13). The patients were from an area with low liver cancer incidence and with low hepatitis B and C prevalence. Patients with a benign liver disease (n=24) were included as controls. Paraffin-embedded liver samples were examined by a Helicobacter genus-specific PCR assay as well as group-specific PCR assays for Enterobacteriaceae, Bacteroides, Lactobacillus and Enterococcus. PCR products of positive samples were characterised by denaturing gradient gel electrophoresis (DGGE) and DNA sequencing.

RESULTS

PCR assay detected Helicobacter DNA in seven of 12 (58%) and eight of 13 (62%) normal liver tissue specimens from HCC and CC patients, respectively. Two cancer samples from HCC patients were Helicobacter-positive but none of the CC cancers. In the control group, three of 24 (12.5%) patients with a benign liver condition were positive for Helicobacter species (p<0.01 compared to results of tumour-free liver tissue from the cancer patients). DGGE and DNA sequence analysis showed that 90% of the detected PCR products were "H. pylori-like". DNA of some other enteric bacteria was detected in the liver of one cancer patient and one control (4% of all patients).

CONCLUSION

The presence of DNA of Helicobacter species in liver specimens, but not of other common gut bacteria, was associated with human hepatic carcinogenesis.

Improving health profile of blood donors as a consequence of transfusion safety efforts

BACKGROUND

Transfusion safety rests heavily on the health of blood donors. Although they are perceived as being healthier than average, little is known about their long-term disease patterns and to which extent the blood banks' continuous efforts to optimize donor selection has resulted in improvements. Mortality and cancer incidence among blood donors in Sweden and Denmark was investigated.

STUDY DESIGN AND METHODS

All computerized blood bank databases were compiled into one database, which was linked to national population and health data registers. With a retrospective cohort study design, 1,110,329 blood donors were followed for up to 35 years from first computer-registered blood donation to death, emigration, or December 31, 2002. Standardized mortality and incidence ratios expressed relative risk of death and cancer comparing blood donors to the general population.

RESULTS

Blood donors had an overall mortality 30 percent lower (99% confidence interval [CI] 29%-31%) and cancer incidence 4 percent lower (99% CI 2%-5%) than the background population. Mortality rates and cancer incidence were lowest for outcomes that are recognized as being related to lifestyle factors such as smoking or to the selection criteria for blood donation. Blood donors recruited in more recent years exhibited a lower relative mortality than those who started earlier.

CONCLUSION

Blood donors enjoy better than average health. Explicit and informal requirements for blood donation in Scandinavia, although mostly of a simple nature, have successfully refined the selection of a particularly healthy subpopulation.

Diabetes: one of few remarkable differences in clinicopathologic features between cirrhotic and noncirrhotic Swedes with hepatocellular carcinoma

The prognosis of hepatocellular carcinoma (HCC) is usually very poor, so increased knowledge of clinicopathologic characteristics and etiologic factors may improve the clinical handling. Because HCC in many patients is unrecognized before death, it is of particular interest to study cases from a period with a high autopsy frequency. The records and liver biopsies from all patients with a diagnosis of primary liver cancer in Göteborg, Sweden, during a 22-year period were scrutinized. Only patients with evaluable non-neoplastic liver tissue were included in the final analysis. The majority (95%) of 478 HCC cases were autopsied and cirrhosis of the liver could be established in 71%. At presentation, general paramalignant symptoms such as malaise, weight loss, anorexia, and hepatomegaly (84%) were common irrespective of cirrhosis. Alcoholism and diabetes mellitus were each significantly more common among cirrhotics (29% and 20%, respectively; P < .001), than among noncirrhotics, in which cholelithiasis was more common (54%; P < .001). The correlation between diabetes and cirrhosis was independent of reported alcoholism. In an unselected population in a low HCC incidence area, there are few differences in clinicopathologic features between cirrhotic and noncirrhotic patients. Diabetes mellitus seems to play an etiologic role in HCC in cirrhotics, and cholelithiasis in noncirrhotics.

Alcohol and hepatocellular carcinoma

More than 18 million adults in the United States abuse alcohol, a prevalence 5 times higher than that of hepatitis C. Chronic alcohol use of greater than 80 g/day for more than 10 years increases the risk for hepatocellular carcinoma (HCC) approximately 5-fold; alcohol use of less than 80 g/day is associated with a nonsignificant increased risk for HCC. The risk for HCC in decompensated alcohol induced cirrhosis approaches 1% per year. The risk does not decrease with abstinence, and HCC can occur in a noncirrhotic liver. Alcohol use in chronic hepatitis C doubles the risk for HCC as compared with the risk in hepatitis C alone. Furthermore, there may be synergism between alcohol and hepatitis C in the development of HCC, and in these patients HCC may occur at an earlier age and the HCC may be histologically more advanced. Studies in the United States and Italy suggest that alcohol is the most common cause of HCC (accounting for 32%-45% of HCC). The mechanisms by which alcohol causes HCC are incompletely understood, but may include chromosomal loss, oxidative stress, a decreased retinoic acid level in the liver, altered DNA methylation, and genetic susceptibility. Alcohol use is increasing in many countries, suggesting that alcohol will continue to be a common cause of HCC throughout the world.

The Gambia Liver Cancer Study: Infection with hepatitis B and C and the risk of hepatocellular carcinoma in West Africa

Hepatocellular carcinoma (HCC) is the most common cancer in The Gambia. Hepatitis B virus (HBV) infection is endemic, with 15% to 20% of the population being chronic carriers, whereas hepatitis C virus (HCV) prevalence is low. We recruited 216 incident cases of HCC and 408 controls from three sites. HBV carriage was present in 61% (129/211) of HCC patients and 16% (64/402) of controls, whereas 19% (36/191) of HCC patients were HCV seropositive compared with 3% (11/382) of controls. HCC patients with HCV were notably older and were more likely to be female than those with HBV. Increased HCC risk was strongly associated with chronic HBV (odds ratio, 16.7; 95% CI, 9.7-28.7), HCV (16.7; 6.9-40.1), and dual infection (35.3; 3.9-323). We interpret the additive nature of risk with coinfection as representative of HBV and HCV acting primarily through shared steps in the multistage process of hepatocarcinogenesis. HCV infection was not observed among younger participants, suggesting a possible cohort effect. Reasons for the striking age and gender differences in HCC associated with HBV compared with HCV are unclear, but transmission patterns and age at exposure may be factors. In conclusion, in a standardized evaluation of well-characterized study participants from The Gambia, most cases of HCC are attributable to HBV (57%), but HCV adds a significant fraction (20%), especially among older patients and females. If HCV transmission is not perpetuated in future cohorts, focusing available resources on HB vaccination efforts could greatly ameliorate a major cause of cancer death in sub-Saharan Africa.

Rising incidence of hepatocellular carcinoma: the role of hepatitis B and C; the impact on transplantation and outcomes

Hepatocellular carcinoma caused by hepatitis B and hepatitis C are global scourges but are likely to peak in incidence in the next 2 decades and then decline. Universal vaccination has been effective in stemming the incidence of chronic hepatitis B and early-onset HCC in regions of high endemicity where implemented, but preventive measures in HCV are not yet available. After the attrition of older affected generations, the incidence of HCC will likely decline rapidly. While no vaccine is currently available for hepatitis C, cases are projected to peak and decline because of a marked reduction in transmission as a result of behavioral modification and safeguarding of blood supplies. Until these epidemiologic projections come to pass, management of hepatocellular carcinoma will continue to become a progressively more frequently encountered clinical challenge. Therapy for chronic hepatitis may ameliorate but will not eliminate the development of tumors. The demand for orthotopic liver transplantation will continue to climb, and palliative therapies for non-resectable cases will require studies aimed at optimization of benefit. LDLT may remain an option for high-risk patients affording tumor-free survival for some otherwise terminal patients.

Risk factors for cholangiocarcinoma in a low risk Caucasian population

OBJECTIVES

Little is known about the etiology of cholangiocarcinoma, apart from its association with liver fluke infestation.

METHODS

A case-control study was conducted in Athens and included six cholangiocarcinoma cases, 333 hepatocellular carcinoma cases and 360 controls with minor ailments or injuries. All subjects were interviewed and tested for hepatitis B and C infection. For all six cholangiocarcinomas, 97 hepatocellular carcinomas and 129 controls, sex steroids were determined in the blood.

RESULTS

Hepatitis B or C viruses, tobacco smoking, alcohol drinking and diabetes mellitus were not related to cholangiocarcinoma, but history of thyroid disease was. Estradiol levels were higher among cholangiocarcinoma cases than among the other two groups.

CONCLUSIONS

This study provides evidence that endocrine and autoimmune factors are important in the etiology of cholangiocarcinoma.

International trends and patterns of primary liver cancer

Primary liver cancer (PLC) is common in many areas of the developing world, but uncommon in most of the developed world. Some evidence suggests, however, that the global pattern of PLC may be changing. To clarify this issue, we examined incidence rates for PLC over the 15-year time period, 1978-92, in selected cancer registries around the world. With some exceptions, developed countries have experienced PLC increases in incidence whereas developing countries have experienced declines. Although the reasons for the trends are not entirely clear, the increased seroprevalence of HCV in the developed world and the elimination of HBV-cofactors in the developing world are likely to have contributed to the patterns. Further progress against PLC may be seen in the developing world once the HBV-vaccinated segment of the population reaches adulthood. Published 2001 Wiley-Liss, Inc.

Screening for hepatocellular carcinoma

Screening for hepatocellular carcinoma has become widely practised in the management of patients with end-stage liver disease. However, the theoretical basis for this practice is largely lacking. Issues such as the selection of the target population and the correct method of confirming positive screening tests have yet to be resolved. Complicating the assessment of screening strategies is the poor literature on comparing different forms of therapy. Nonrandomized, uncontrolled studies that do not account for lead-time bias make it frequently impossible to know whether an applied treatment has really improved survival. Despite these difficulties, screening is reality, and strategies have to be devised to efficiently screen patients, find small tumours and apply effective treatments. Some practical strategies are discussed.

Chronic hepatitis C in Sweden: genotype distribution over time in different epidemiological settings

Hepatitis C virus (HCV) strains are divided into 6 genotypes and several subtypes. Recent studies reported a change in the relative frequency of genotypes within certain regions. We studied the HCV genotype in 312 Swedish patients with chronic hepatitis C, using a core region primer-specific PCR, and grouped the patients according to parenteral risk factors. The date of infection could be estimated in 127 cases. Genotypes 1a (35%) and 3 (31%) were the most common genotypes, followed by genotype 2 (17%), while only 6% had genotype 1b. Genotype 3 was relatively more frequent among subjects infected sexually or by intravenous drug use. The genotype distribution was different from that in studies from other parts of the world, with a lower frequency of genotype 1 (especially 1b) and a higher frequency of genotype 3. The frequency of genotype 1b has decreased and genotype 3 increased over time. The reasons for a different distribution of genotypes in Sweden, compared with other countries, might be a relatively recent introduction of HCV into the population, or a different pattern of transmission.

A meta-analysis of epidemiological studies on the combined effect of hepatitis B and C virus infections in causing hepatocellular carcinoma

The aim of the study was to assess whether co-infection by hepatitis-B virus (HBV) and hepatitis-C virus (HCV) is associated with a higher risk of developing hepatocellular carcinoma (HCC) than each infection alone. A meta-analysis of data published up to June 1997 was performed. HBsAg and anti-HCV antibodies or HCV RNA (anti-HCV/HCV RNA) were considered as serological markers of current HBV and HCV infection respectively. A total of 32 case-control studies were suitable for a quantitative overview. The summary odds ratios (OR) were 13.7 for HBsAg positivity and 11.5 for anti-HCV/HCV RNA positivity. The OR for anti-HCV was lower among studies using second- or third-generation anti-HCV or HCV RNA (OR, 8.2) with respect to studies with first-generation anti-HCV test (OR, 19.1). When combining data from the studies with second- or third-generation anti-HCV or HCV RNA, the OR for HBsAg positivity and anti-HCV/HCV RNA negativity was 22.5 (95% confidence interval (CI), 19.5-26.0), the OR for anti-HCV/HCV RNA positivity and HBsAg negativity was 17.3 (95% CI, 13.9-21.6), and the OR for both markers positivity was 165 (95% CI: 81.2-374, based on 191 cases and 8 controls exposed). A synergism was found between HBV and HCV infections, the OR for co-infection being greater than the sum and lower than the product of those for each infection alone. The interaction was therefore negative according to the multiplicative model, providing epidemiological evidence both of an independent effect and of interference between the 2 viruses in the carcinogenic process.