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Query: UMLS:C0345904 (liver cancer)
 15,188 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

It is frequently assumed that the risk of hepatocellular carcinoma related to hepatitis B virus is higher when chronic hepatitis B virus infection is acquired early in life. This hypothesis has never been directly evaluated. However, firstborn and secondborn children are exposed to common infections after their school enrollment, whereas laterborn children are exposed much earlier, through their older siblings. The authors analyzed sibship size and birth order data from a large case-control study of patients admitted to Athens, Greece, hospitals between April 1976 and October 1984. The analyses included 185 patients with hepatocellular carcinoma, 35 patients with metastatic liver cancer, and 432 other hospital controls. There was a tendency for cases of hepatocellular carcinoma to concentrate at higher birth orders. When the analysis was restricted to cases and controls who were positive for hepatitis B surface antigen, this tendency was even more notable. These results are compatible with the hypothesis that establishment of chronic hepatitis B virus infection at an early age increases the risk of hepatocellular carcinoma substantially more than does chronic infection with this virus established at a later age.
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PMID:Age at first establishment of chronic hepatitis B virus infection and hepatocellular carcinoma risk. A birth order study. 133 66

Aflatoxins have long been suspected to be human hepatic carcinogens but no direct study was feasible until assays to measure individual aflatoxin exposure became available. We have used assays for urinary aflatoxin B1, its metabolites AFP1 and AFM1, and DNA-adducts (AFB1-N7-Gua) to assess the relation between aflatoxin exposure and liver cancer, as part of an ongoing prospective study of 18,244 middle-aged men in Shanghai, People's Republic of China. After 35,299 person-years of follow-up, 22 cases of liver cancer had been identified. For each case, 5 or 10 controls were randomly selected from cohort members without liver cancer on the date the disorder was diagnosed in the case and matched to within 1 year for age, within 1 month for sample collection, and for neighbourhood of residence. Subjects with liver cancer were more likely than were controls to have detectable concentrations of any of the aflatoxin metabolites (relative risk 2.4, 95% confidence interval 1.0-5.9). The highest relative risk was for aflatoxin P1 (6.2, 1.8-21.5). In an analysis adjusting for the effects of hepatitis B surface antigen seropositivity, level of education, cigarette smoking, and alcohol consumption, the relative risk for the presence of aflatoxin metabolites was 3.8 (1.2-12.2). There was a strong interaction between serological markers of chronic hepatitis B infection and aflatoxin exposure in liver-cancer risk. Reduction of aflatoxin exposure may be a useful intermediate goal in prevention of liver cancer, since the benefits of wide-scale hepatitis B vaccination will not be apparent for many years.
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PMID:Urinary aflatoxin biomarkers and risk of hepatocellular carcinoma. 135 Aug 20

In Okinawa prefecture, prevalence of hepatitis B surface antigen (HBsAg) among blood donors is 3.5% and is twice as high as the average for the whole of Japan (1.5%), and is the highest in Japan (p less than 0.005). In contrast, mortality rates of both liver cirrhosis (LC) and primary liver cancer (PLC) in Okinawa are the lowest in Japan. Many epidemiological studies have shown that the positive rate of HBsAg correlates with mortality rate of PLC. To elucidate the cause of this epidemiological discrepancy, cross-sectional seroepidemiological studies and a prospective clinical study were conducted. In the cross-sectional studies, the following results were obtained; (1) Positive rate of HBsAg among patients with LC in Okinawa was 15.2% and lower than the average for the whole of Japan (23.4%). A similar comparison among patients with hepatocellular carcinoma showed 24.4% in Okinawa Vs. 31.4% in the whole of Japan. (2) The age-specific hepatitis B e antigen positive rate among 829 HBsAg positive health examinees tend to decrease with increase in age; 50% in less than 20 years old age group, 15.7% in third decade and 2-3% or less in 30 or more age group. Of the 829, 431 HBsAg positive subjects were referred our liver out-patient clinic. Then, of the 431, 27 (6.3%) were diagnosed or suspected as having chronic hepatitis and one (0.2%) was diagnosed as having cirrhosis. Of the 431, 381 (88.4%) were diagnosed as healthy HBsAg carrier, the great majority (94.0%) of whom had positive reaction of anti-HBe antibody and normal values of both GOT and GPT.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Correlation between hepatitis B virus infection and chronic liver disease in Okinawa]. 140 58

The relative contribution of aflatoxins (AF) and hepatitis B virus (HBV) to the aetiology of liver cancer remains to be determined, as does the mechanism of any interaction between these two factors. Methods to measure individual exposure to AF permit the assessment of this possible interaction in field studies. The measurement of AF covalently bound to albumin in peripheral blood has been particularly useful in this respect. In east and west African countries the majority (75-100%) of individuals has been found positive (> 5 pg AFB1-lysine eq./mg albumin) for the AF-albumin adduct with levels ranging up to 720 pg/mg. Levels of adduct to date have been age- and sex-independent, although marked seasonal variations were seen in The Gambia. Exposure also occurs in utero, with the AF-adduct being found in umbilical cord blood. In a study in The Gambia involving 323 children (age 3-8 years) the AF-albumin adduct levels were examined with respect to HBV infection and ethnic group. Over 95% of all sera contained detectable adduct but children positive for HBV surface antigen (HBsAG) had significantly higher adduct levels than children with markers of past infection or who had never been infected (mean (log) AF-albumin adduct levels 4.41 +/- 0.95, 4.04 +/- 0.99, and 4.05 +/- 1.03 respectively, p = 0.04). In addition, there were highly significant differences in adduct levels between the three major ethnic groups (Wollof 4.41 +/- 0.69: Fula 4.05 +/- 1.1; Mandinka 3.7 +/- 1.14). Wollof children were also more likely to be HBsAg positive than the other two groups. These data suggest that ethnic group and HBV infection can influence AF metabolism and this is being examined in this population with respect to genetic polymorphisms in cytochrome P450 and glutathione-S-transferase enzymes. In addition, these biomarkers are being compared to the nature and frequency of mutations in somatic and tumour cells.
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PMID:Field studies of aflatoxin exposure, metabolism and induction of genetic alterations in relation to HBV infection and hepatocellular carcinoma in The Gambia and Thailand. 147 Nov 97

The incidence of primary carcinoma of the liver in Sweden has been reported to increase. In order to study the role of chronic hepatitis B virus (HBV) infection for liver cancer development 40 cases with hepatocellular carcinoma (HCC) were examined for the presence of HBV surface antigen and HBV core antigen in the cancer and in the surrounding non-neoplastic liver tissue. It was not possible to demonstrate a single case with tissue HBV antigen, indicating that HBV plays a minor role in the etiology of HCC in Sweden and thus does not seem to be responsible for the increasing incidence of this cancer.
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PMID:Lack of correlation between hepatitis B virus infection and the increasing incidence of primary liver cancer in Sweden. 166 21

Alpha-fetoprotein (AFP) was detected, by Ouchterlony immunodiffusion technique, in 81.5% of patients with histologically confirmed diagnosis of hepatocellular carcinoma. The test gave negative results with 35 cases of acute viral hepatitis, 7 haemochromatosis, 6 micronodular cirrhosis and 2 cholangiocellular carcinoma. Curiously, one patient with postnecrotic cirrhosis, a well recognized sequela of viral hepatitis, whose liver cell regeneration also showed "atypical changes", was AFP positive. AFP was not detected in sera from the general population which comprised 1029 male blood donors, 144 antenatal and 106 maternity cases. The only exception was the case of a woman who aborted a 5-month old foetus. A follow-up serum sample taken 3 months later was, however, negative for AFP. The frequency of hepatitis B surface antigen (HBsAg) detection in patients with hepatocellular carcinoma (25.9%) was 4 to 5 times higher than that in the general population. This strong association between HBsAg and primary liver cancer in countries where liver tumours are often AFP secretors suggests a role for hepatitis B virus, not only in the aetiology of the cancer, but also in the reactivation of the gene encoding this foetal protein.
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PMID:A study of alpha-fetoprotein in primary liver cancer in Tanzania. 172 52

The purpose of this study was to evaluate the effect of selenium (Se) in the prevention of human primary liver cancer. Three intervention trials were conducted among the residents at high risk to primary liver cancer (PLC) in Qidong county, Jiang-su province, the People's Republic of China. This area has the second highest rate of PLC in China. One trial was undertaken among the general population in a township with supplement of table salt fortified with 15 ppm anhydrous sodium selenite (Se-salt) for 5 y and the other four townships with similar PLC incidence rate served as the controls using normal table salt. The second trial was undertaken among hepatitis B virus surface antigen carriers (HBVsAg+) receiving supplement of 200 micrograms Se in form of selenized yeast (Se-yeast) daily vs placebo for 4 y. The third trial was carried out in members of families with high PLC incidence using Se-yeast (200 micrograms of Se daily) vs placebo for 2 y. The results showed that nutritional supplement of Se could reduce the PLC incidence significantly.
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PMID:A preliminary report on the intervention trials of primary liver cancer in high-risk populations with nutritional supplementation of selenium in China. 172 11

As part of The Gambia Hepatitis Intervention Study (designed to protect children from hepatitis and therefore liver cancer when adults), researchers took blood samples from at least 291 families of 293 index children from Brikama in the western region and 2 neighboring health centers in the Upper River Division (URD) in the eastern area of The Gambia who had received the hepatitis B virus (HBV) vaccine to examine vaccine response in infants in relation to the pattern of HBV infection in their families. 1 family member tested positive for hepatitis B surface antigen (HBsAg) in at least 30% of the children. The researchers did not find a correlation between the level of antibody in the index children and the HBsAg status of the family. 23% of families in Brikama had at least 1 HBsAg positive member compared to 37% in URD (p=.01). Even though no association existed between child's response to the vaccine and type of dwelling, an association did exist between HBsAg positive family members and type of dwelling. 35% of families who lived in a house constructed of mud or grass had at least 1 HbsAG positive family member whereas only 19.7% who lived in a concrete house had at least 1 HBsAg positive family member (p.02). Further, 40.8% of families who lived under a thatched roof had at least 1 HbsAg positive family member compared to 24.8% who had a corrugated roof (p.02). The researchers suggested that houses constructed of mud or grass or with a thatched roof may harbor more insects which transmit HBV. The socioeconomic factors of sanitation and water supply did not contribute to HBV infection. They concluded that the HBV status of a child's family did not affect his/her response to the vaccine. Therefore the vaccine protects children at high risk of becoming HBV carriers.
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PMID:Response to hepatitis B vaccine in relation to the hepatitis B status of family members. 183 53

Serum taken from patients in a case-control study in Athens, Greece, was used to examine the interactive roles of hepatitis B virus (HBV) and hepatitis C virus (HCV) in the origin of hepatocellular carcinoma (HCC). An enzyme immunoassay for anti-HCV was used to test serum taken from 185 cases with HCC, 35 cases with metastatic liver cancer (MLC), and 432 hospital controls. Weakly positive anti-HCV results were more strongly related to MLC than to HCC, implying that these anti-HCV results are false positive. By contrast, strongly positive anti-HCV results were significantly related to HCC (relative risk [RR], 6.3), whereas no significant association was evident for MLC (RR, 0.6). The association of anti-HCV with HCC was substantially higher among subjects whose radioimmunoassay was positive for hepatitis B surface antigen (RR, 20.0) than among those whose radioimmunoassay was negative for this marker (RR, 4.8). These findings indicate that HCV infection has an interactive role in the origin of HCC.
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PMID:Hepatitis B and C viruses and their interaction in the origin of hepatocellular carcinoma. 184 8

Some of the major difficulties in assessing the role of aflatoxin (AF) in the causation of liver cancer are discussed. Firstly, exposure to AF in Africa and parts of Asia and Latin America might begin very early in life and episodically thereafter. The number of episodes and the degree of exposure to AF varies greatly by country and region, by agricultural and crop storage practices, by season and by other factors difficult to control in any questionnaire-based study. Secondly, there is a high geographical correlation between exposure to AF and to hepatitis B virus. Thirdly, long-lasting biological markers for AF are still not available. Epidemiological studies might be enhanced by the incorporation of new biological assays. It is to be hoped that better information will be generated as a result of on-going intervention projects, such as reduction of AF levels and agricultural development programmes, and by monitoring exposure to AF and the incidence of liver cancer in areas where hepatitis B virus vaccination is effectively reducing the prevalence of carriers of the viral surface antigen.
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PMID:Aflatoxins: data on human carcinogenic risk. 185


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