Cigarette smoking and liver cancer risk: an evaluation based on a systematic review of epidemiologic evidence among Japanese

Documento de consenso sobre tabaquismo y riesgo vascular

Consensus statement on smoking and vascular risk About 22% of the Spanish population are daily smokers. Men are more likely to smoke than women. In Spain, women between 15-25 years of age smoke as much or more than men. Every smoker should be assessed for: physical dependence on nicotine (Fagerström test), social and psychological dependence (Glover Nilsson test), level of motivation to quit (Richmond test), probability of therapy success (Henri-Mondor and Michael-Fiore tests), and stage of behavioral change development (Prochaska and DiClementi). Advice on smoking cessation is highly cost-effective and should always be provided. Smoking is an enhancer of cardiovascular risk because it acts as a pathogen agent in the development of arteriosclerosis and is associated with ischemic heart disease, stroke, and peripheral artery disease. Smoking increases the risk of chronic lung diseases (COPD) and is related to cancers of the lung, female genitalia, larynx, oropharynx, bladder, mouth, esophagus, liver and biliary tract, and stomach, among others. Combined oral contraceptives should be avoided in women smokers older than 35 years of age due to the risk of thromboembolism. In smoking cessation, the involvement of physicians, nurses, psychologists, etc. is important, and their multidisciplinary collaboration is needed. Effective pharmacological treatments for smoking cessation are available. Combined treatments are recommended when smoker's dependence is high. For individuals who are unable to quit smoking, a strategy based on tobacco damage management with a total switch to smokeless products could be a less dangerous alternative for their health than continuing to smoke.

Assessments of TP53 and CTNNB1 gene hotspot mutations in circulating tumour DNA of hepatitis B virus-induced hepatocellular carcinoma

Background: Hepatitis B virus (HBV) infection is one of the major causes of chronic liver disease, which progresses from chronic hepatitis B (CHB) to fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). Early detection and laboratory-based screening of hepatocellular carcinoma are still major challenges. This study was undertaken to determine whether the cancer hallmark gene signatures that are released into circulation as circulating tumour DNA (ctDNA) can be used as a liquid biopsy marker for screening, early detection, and prognosis of HCC. Methods: A total of 130 subjects, including HBV-HCC (n = 80), HBV-cirrhotic and non-cirrhotic (n = 35), and healthy (n = 15) controls, were evaluated for TP53 and beta-catenin (CTNNB1) gene hotspot mutations in ctDNA by Sanger-based cycle sequencing and droplet digital PCR (ddPCR) assays. Mutation detection frequency, percentage mutant fractions, and their association with tumour stage, mortality, and smoking habits were determined. Results: Sanger-based cycle sequencing was carried out for 32 HCC patients. Predict SNP Tools analysis indicated several pathogenic driver mutations in the ctDNA sequence, which include p.D228N, p.C229R, p.H233R, p.Y234D, p.S240T, p.G245S, and p.R249M for TP53 gene exon 7 and p.S33T for CTNNB1 gene exon 3. The TP53 c.746G>T (p.R249M) mutation was detected predominately (25% cases) by sequencing, but there was no dominant mutation at position c.747G>T (p.R249S) that was reported for HBV-HCC patients. A dual-probe ddPCR assay was developed to determine mutant and wild-type copy numbers of TP53 (p.R249M and p.R249S) and CTNNB1 (p.S45P) and their percentage mutant fraction in all 130 subjects. The TP53 R249M and CTNNB1 S45P mutations were detected in 31.25% and 26.25% of HCC patients, respectively, with a high mutant-to-wild-type fraction percentage (1.81% and 1.73%), which is significant as compared to cirrhotic and non-cirrhotic patients. Poor survival was observed in HCC patients with combined TP53 and CTNNB1 gene driver mutations. The TP53 R249M mutation was also significantly (p < 0.0001) associated with smoking habits (OR, 11.77; 95% CI, 3.219-36.20), but not the same for the TP53 R249S mutation. Conclusion: Screening of ctDNA TP53 and CTNNB1 gene mutations by ddPCR may be helpful for early detection and identifying the risk of HCC progression.

Cigarette smoking and liver diseases

Cigarette smoking is a preventable risk factor for premature morbidity and mortality. A history of smoking is observed in approximately 40% of patients with liver disease, while a growing number of studies are investigating the potential impact of smoking in chronic liver diseases. This review discusses the effects of smoking on liver diseases, at multiple levels, with a focus on its potential causal role. Clinical evidence indicates that cigarette smoking negatively impacts the incidence and severity of fatty liver disease, fibrosis progression, hepatocellular carcinoma development, and the outcomes of patients with advanced liver disease. The underlying mechanisms are complex and involve different pathophysiological pathways including oxidative stress and oncogenic signals. Importantly, smoking promotes cardiovascular disease and extrahepatic cancers in patients with steatohepatitis and in transplant recipients. We discuss how promoting smoking cessation could improve the rates of treatment response (in clinical trials) and fibrosis regression, while reducing the risk of hepatocellular carcinoma and improving liver transplant outcomes. Finally, we discuss current challenges such as the referral of smokers to specialised units for smoking cessation.

Tobacco, Cigarettes, and the Liver: The Smoking Gun

The association between alcohol and liver disease, including alcoholic hepatitis, cirrhosis, acute-on-chronic liver failure, and hepatocellular carcinoma, has been well described, but the same cannot be said for the association between smoking, water pipe or tobacco chewing. A review of cumulative evidence suggests that smoking is independently a risk factor for liver fibrosis and contributes to carcinogenesis in HCC. Smoking-related fibrosis has been reported in patients with nonalcoholic fatty liver disease, primary biliary cholangitis, alcoholic liver disease and chronic viral hepatitis. Heavy smoking leads to systemic inflammation, oxidative stress, insulin resistance, and results in tissue hypoxia, as well as free radical damage. Other than damaging the liver, patients also suffer from the systemic effects of the 4000 chemicals associated with tobacco, which include nitrosamines, aromatic hydrocarbons, nicotine, nornicotine, and other alkaloids. These include respiratory ailments, cancer of the lungs, oral cavity, esophagus, pancreas and colon, atherosclerotic vascular disease, and stroke.

Chemical Risk Factors of Primary Liver Cancer: An Update

Primary liver cancer has the sixth highest incidence and fourth highest cancer mortality worldwide. Hepatitis B is the leading cause of liver cancer, though its incidence is decreasing with vaccination. Alcohol is the leading cause of liver transplant, cirrhosis, and cancer in the developed world, and is projected to surpass hepatitis B as the leading hepatic cancer etiology worldwide. Tobacco smoking has shown a positive association with liver cancer in a majority of studies, though not all. Aflatoxin, a mycotoxin produced by Aspergillus, is estimated to account for 3–20% of global liver cancer cases, 40% of which occur in sub-Saharan Africa. These statistics are confounded by the prevalence of hepatitis B, which may have a synergistic effect on hepatic carcinogenesis. Aflatoxin is ingested and likely inhaled from agricultural products, placing farmers, food processors, and textile workers in developing nations at risk. Vinyl-chloride is used in the production of PVC plastics and causes rare liver angiosarcoma, hepatocellular carcinoma, and other neoplasms. Arsenic and cadmium are naturally-occurring, hepatocarcinogenic metals with high occupational exposure in industries involving coal, metals, plastics, and batteries. Millions of laborers in waste-disposal and manufacturing are exposed to organic solvents and N-nitrosamines, which vary from carcinogenic (group 1) to possibly carcinogenic (group 2B) in their IARC designation. Insecticide DDT is possibly hepatocarcinogenic (group 2B), though continues to be used for malaria control in the developing world. While suggested by case reports, anabolic steroids and oral contraceptives have not been shown to increase liver cancer risk in large studies.

Responses of smoking and nonsmoking cancer patients to drug treatment: A protocol for systematic review and meta-analysis

INTRODUCTION

Smoking is well-known to increase cancer risk, particularly risk of lung cancer, and negatively affects efficacy of cancer treatment. However, recent evidence suggests that among cancer patients, paradoxically, smokers respond to treatment better than non-smokers. We propose to conduct a focused review and meta-analysis to compare response to drug treatment between smoking and non-smoking cancer patients.

METHODS AND DESIGN

We will collect data from large clinical trials of therapies for cancer patients which have included smokers and non-smokers. We will search PubMed, PMC/ MEDLINE, SCOPUS, Embase, and the registries for clinical trials and four major clinical journals up to June 30, 2019. Search terms will be "Drug name" phase-3" or "Drug name" phase-III." Data collection will be focused on randomized clinical trials of cancer drugs that enrolled at least 100 participants and reporting treatment results from smoking and nonsmoking patients. Initial selection criteria will be clinical trial studies of drug treatment of 100 or more cancer patients, and reporting hazard ratios (HR) for smokers and non-smokers. Two persons will be searching such publications independently, or data will be provided, double checked, or confirmed by authors. Multiple sub-group analyses will be conducted by at least two persons to avoid bias or experimental errors.

DISCUSSION

The results will clarify whether smoking and response to treatment of cancer are linked not. Our results may possibly identify drug/s that work better among cancer patients who are smokers.

TRIAL REGISTRATION

PROSPERO registration number: CRD42019146402.

Assessment of risk factors, and racial and ethnic differences in hepatocellular carcinoma

Despite improved screening and surveillance guidelines, significant race/ethnicity‐specific disparities in hepatocellular carcinoma (HCC) continue to exist and disproportionately affect minority and disadvantaged populations. This trend indicates that social determinants, genetic, and environmental factors are driving the epidemic at the population level. Race and geography had independent associations with risk of mortality among patients with HCC. The present review discusses the risk factors and issues related to disparities in HCC. The underlying etiologies for these disparities are complex and multifactorial. Some of the risk factors for developing HCC include hepatitis B (HBV) and hepatitis C (HCV) viral infection, nonalcoholic fatty liver disease, nonalcoholic steatohepatitis, smoking and alcohol consumption. In addition, population genetics; socioeconomic and health care access; treatment and prevention differences; and genetic, behavioral, and biological influences can contribute to HCC. Acculturation of ethnic minorities, insurance status, and access to health care may further contribute to the observed disparities in HCC. By increasing awareness, better modalities for screening and surveillance, improving access to health care, and adapting targeted preventive and therapeutic interventions, disparities in HCC outcomes can be reduced or eliminated.

Cigarette smoking and cervical cancer risk: an evaluation based on a systematic review and meta-analysis among Japanese women

Background

There is a body of evidence to suggest that cigarette smoking increases the risk of cervical cancer in women, but no study has examined the magnitude of the association in Japanese women. Here, we evaluated the association between cigarette smoking and the risk of cervical cancer in Japanese women based on a systematic review of epidemiological evidence.

Methods

Original data were obtained from a MEDLINE search using PubMed or from a search of the 'Ichushi' database, as well as by a manual search. Evaluation of associations was based on the strength of evidence and the magnitude of association, together with biological plausibility as evaluated previously by the International Agency for Research on Cancer. Meta-analysis of associations was also conducted to obtain a summarized overview of the data.

Results

We identified two cohort studies and three case-control studies. All five studies had indicated strong positive associations between cigarette smoking and the risk of cervical cancer. Our summary estimate indicated that the relative risk (RR) for individuals who had ever-smoked relative to never-smokers was 2.03 (95% confidence interval: 1.49-2.57). Four studies had also demonstrated dose-response relationships between cigarette smoking and the risk of cervical cancer.

Conclusion

We conclude that there is convincing evidence that cigarette smoking increases the risk of cervical cancer among Japanese women.

Evidence-based cancer prevention recommendations for Japanese

A comprehensive evidence-based cancer prevention recommendation for Japanese was developed. We evaluated the magnitude of the associations of lifestyle factors and infection with cancer through a systematic review of the literature, meta-analysis of published data, and pooled analysis of cohort studies in Japan. Then, we judged the strength of evidence based on the consistency of the associations between exposure and cancer and biological plausibility. Important factors were extracted and summarized as an evidence-based, current cancer prevention recommendation: 'Cancer Prevention Recommendation for Japanese'. The recommendation addresses six important domains related to exposure and cancer, including smoking, alcohol drinking, diet, physical activity, body weight and infection. The next step should focus on the development of effective behavior modification programs and their implementation and dissemination.

Impact of tobacco smoking on the risk of developing 25 different cancers in the UK: a retrospective study of 422,010 patients followed for up to 30 years

BACKGROUND

The aim of this study was to analyze the impact of tobacco smoking on the risk of developing 25 different cancers in patients followed for up to 30 years in general practices in the UK.

METHODS

This study included all individuals with at least one visit to one of 196 general practitioners' offices in the UK between January 1988 and December 2008 (index date). Only individuals with documented smoking status were included. Smokers and non-smokers were matched (1:1) by age, gender, index year, body mass index, and physician. The main outcome of the study was the risk of cancer as a function of smoking status. Data regarding a total of 25 cancers were available for the present analysis. The risk of cancer was analyzed using Cox's regression model.

RESULTS

The present retrospective study included 211,005 smokers and 211,005 non-smokers. The mean age was 36.5 years (SD = 12.5 years) in men and 34.3 years (SD = 13.1 years) in women. There was a slightly positive association between smoking and any cancer in both men (HR = 1.07) and women (HR = 1.03). Smoking was further found to be positively associated with several cancers, such as liver cancer, bladder and kidney cancers, pancreas cancer, and lymphoma. By contrast, the use of tobacco was negatively associated with the risk of developing skin cancer, prostate cancer, multiple myeloma, endometrial carcinoma, or breast cancer.

CONCLUSIONS

Smoking increased the overall risk of cancer in primary care practices in the UK. In addition, smoking was predominantly positively and less frequently negatively associated with numerous specific cancers.

Correlation between smoking habit and surgical outcomes on viral-associated hepatocellular carcinomas

AIM

To investigate the association between smoking habits and surgical outcomes in hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) (B-HCC) and hepatitis C virus (HCV)-related HCC (C-HCC) and clarify the clinicopathological features associated with smoking status in B-HCC and C-HCC patients.

METHODS

We retrospectively examined the cases of the 341 consecutive patients with viral-associated HCC (C-HCC, n = 273; B-HCC, n = 68) who underwent curative surgery for their primary lesion. We categorized smoking status at the time of surgery into never, ex- and current smoker. We analyzed the B-HCC and C-HCC groups’ clinicopathological features and surgical outcomes, i.e., disease-free survival (DFS), overall survival (OS), and disease-specific survival (DSS). Univariate and multivariate analyses were performed using a Cox proportional hazards regression model. We also performed subset analyses in both patient groups comparing the current smokers to the other patients.

RESULTS

The multivariate analysis in the C-HCC group revealed that current-smoker status was significantly correlated with both OS (P = 0.0039) and DSS (P = 0.0416). In the B-HCC patients, no significant correlation was observed between current-smoker status and DFS, OS, or DSS in the univariate or multivariate analyses. The subset analyses comparing the current smokers to the other patients in both the C-HCC and B-HCC groups revealed that the current smokers developed HCC at significantly younger ages than the other patients irrespective of viral infection status.

CONCLUSION

A smoking habit is significantly correlated with the overall and disease-specific survivals of patients with C-HCC. In contrast, the B-HCC patients showed a weak association between smoking status and surgical outcomes.

Smoking cessation and subsequent risk of cancer: A pooled analysis of eight population-based cohort studies in Japan

BACKGROUND

Although East Asia is one of the largest tobacco-epidemic regions in the world, only a few prospective studies from Asia have investigated the impact of smoking and cessation of smoking on cancer. We aimed to assess the effect of cessation of smoking on the risk of cancer using eight population-based cohort studies in Japan.

METHODS

We analyzed pooled data from eight population-based prospective cohort studies in Japan with more than 320,000 participants to assess the effect of smoking cessation on the risk of total cancers and smoking-related cancers.

RESULTS

After adjustment for potential confounders, cancer risks in men with >21years of smoking cessation before baseline were found to decrease to the same level as never smokers for total cancer (never smokers: reference; former smokers with ≥21 years since smoking cessation: HR, 1.01; 95%CI: 0.91, 1.11). Even men who are heavy smokers (more than 20 pack-years) reported a reduced risk of total cancer (never smokers: reference; former smokers with ≥21 years since smoking cessation: HR, 1.06; 95%CI: 0.92, 1.23). In women, the risk of total cancer did not differ from that of never smokers after 11 years of smoking cessation before baseline (never smokers: reference; former smokers with ≥11 years since smoking cessation: HR, 0.96; 95%CI: 0.74, 1.23).

CONCLUSIONS

Our study suggests that longer duration of smoking cessation may attenuate the risk of cancer in both men and women, and that even heavy smokers (more than 20 pack-years) were found to benefit from quitting smoking.

Effects of Curcumin on Tobacco Smoke-induced Hepatic MAPK Pathway Activation and Epithelial-Mesenchymal Transition In Vivo

Tobacco smoke is a major risk factor for hepatic cancer. Epithelial-mesenchymal transition (EMT) induced by tobacco smoke is crucially involved in the initiation and development of cancer. Mitogen-activated protein kinase (MAPK) pathways play important roles in tobacco smoke-associated carcinogenesis including EMT process. The chemopreventive effect of curcumin supplementation against cancers has been reported. In this study, we investigated the effects of tobacco smoke on MAPK pathway activation and EMT alterations, and then the preventive effect of curcumin was examined in the liver of BALB/c mice. Our results indicated that exposure of mice to tobacco smoke for 12 weeks led to activation of ERK1/2, JNK, p38 and ERK5 pathways as well as activator protein-1 (AP-1) proteins in liver tissue. Exposure of mice to tobacco smoke reduced the hepatic mRNA and protein expression of the epithelial markers, while the hepatic mRNA and protein levels of the mesenchymal markers were increased. Treatment of curcumin effectively attenuated tobacco smoke-induced activation of ERK1/2 and JNK MAPK pathways, AP-1 proteins and EMT alterations in the mice liver. Our data suggested the protective effect of curcumin in tobacco smoke-triggered MAPK pathway activation and EMT in the liver of BALB/c mice, thus providing new insights into the chemoprevention of tobacco smoke-associated hepatic cancer. Copyright © 2017 John Wiley & Sons, Ltd.

Impact of smoking habit on surgical outcomes in non-B non-C patients with curative resection for hepatocellular carcinoma

AIM

To analyzed the correlation between smoking status and surgical outcomes in patients with non-B non-C hepatocellular carcinoma (NBNC-HCC), and we investigated the patients’ clinicopathological characteristics according to smoking status.

METHODS

We retrospectively analyzed the consecutive cases of 83 NBNC-HCC patients who underwent curative surgical treatment for the primary lesion at Saga University Hospital between 1984 and December 2012. We collected information about possibly carcinogenic factors such as alcohol abuse, diabetes mellitus, obesity and smoking habit from medical records. Smoking habits were subcategorized as never, ex- and current smoker at the time of surgery. The diagnosis of non-alcoholic steatohepatitis (NASH) was based on both clinical information and pathological confirmation.

RESULTS

Alcohol abuse, diabetes mellitus, obesity and NASH had no significant effect on the surgical outcomes. Current smoking status was strongly correlated with both overall survival (P = 0.0058) and disease-specific survival (P = 0.0105) by multivariate analyses. Subset analyses revealed that the current smokers were significantly younger at the time of surgery (P = 0.0002) and more likely to abuse alcohol (P = 0.0188) and to have multiple tumors (P = 0.023).

CONCLUSION

Current smoking habit at the time of surgical treatment is a risk factor for poor long-term survival in NBNC-HCC patients. Current smokers tend to have multiple HCCs at a younger age than other patients.

Characteristics of patients with liver cancer in the BioBank Japan project

Background

Liver cancer is the fifth cause of cancer-related deaths in Japan. The BioBank Japan (BBJ) project included 200,000 patients with 47 diseases and samples; their clinical information can be used for further studies.

Methods

Patients diagnosed with liver cancer (n = 1733; 1316 men, 417 women) were included. Histology, patient characteristics, clinical characteristics, and causes of death were collected. Cumulative and relative survival rates for liver cancer were calculated.

Results

Of the 1354 patients with available liver cancer histology, 91.9% had hepatocellular carcinoma (HCC). Compared with the National Health and Nutrition Examination Survey, greater proportions of the male patients in this cohort were daily alcohol consumers (26%), and a greater proportion of the men was overweight/obesity (22%). Although Japan is the only Asian country with a predominance of hepatitis C virus (HCV)-related HCC, the prevalence of HCV infection (44%) was lower than that in a previous study. The 3-, 5-, and 10-year cumulative survival rates were 57%, 47%, and 25% in men, respectively, and 49%, 41%, and 27% in women, respectively.

Conclusions

The present results provide an overview of the patients with liver cancer in the BBJ project. We are planning further analyses combined with various high-throughput ‘omics’ technologies.

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Liver cancer is the second leading cause of death worldwide.

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We aimed to provide an overview of patients with liver cancer.

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Based on liver cancer histology, 91.9% had hepatocellular carcinoma.

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The 10-year relative survival rates were 34% in men and 38% in women.

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Future studies will help develop preventive programs for liver cancer.

Diabetes mellitus and liver cancer risk: an evaluation based on a systematic review of epidemiologic evidence among the Japanese population

OBJECTIVE

The potential associations of diabetes mellitus with malignant neoplasms including liver cancer have become a great concern from both clinical and preventive perspectives. Although sufficient evidence for a positive association between diabetes and liver cancer already exists, it would be informative to summarize up-to-date epidemiologic data in Japan.

METHODS

We systematically reviewed epidemiologic studies on diabetes and liver cancer among Japanese populations. Original data were obtained by searching the MEDLINE (PubMed) and Ichushi databases, complemented with manual searches. The evaluation was performed in terms of the magnitude of association in each study and the strength of evidence ('convincing', 'probable', 'possible' or 'insufficient'), together with biological plausibility.

RESULTS

We identified 19 cohort studies, one pooled-analysis of seven cohort studies, and seven case-control studies. Of 24 relative risk estimates of liver cancer for diabetes reported in those cohort studies, 17 showed a weak to strong positive association, six revealed no association and one demonstrated a weak inverse association (summary relative risk 2.10, 95% confidence interval 1.60-2.76). Ten relative risk estimates from the case-control studies showed a weak to strong positive association (n = 9) or no association (n = 1; summary relative risk 2.32, confidence interval 1.73-3.12). Overall, the summary relative risk became 2.18 (confidence interval 1.78-2.69). Heterogeneity in relative risks was significant for the difference in categories of study population (P = 0.01), but not in study type (P = 0.39) or sex (P = 0.33).

CONCLUSIONS

Diabetes mellitus 'probably' increases the risk of liver cancer among the Japanese population.

Advances in cancer epidemiology in Japan

Epidemiologists in Japan have been performing calculations to estimate nationwide cancer incidence rates as well as 5-year survival rates using population-based cancer registry data. There have been remarkable changes in cancer incidence and/or mortality in cancers of the lung, liver and stomach, which were thought to be attributed to the changing impact of exposure to cigarette smoking, chronic hepatitis C virus infection and Helicobacter pylori infection, respectively. In systematic reviews providing evidence in risk/protective factors for cancer sites using case-control and cohort studies of the Japanese population, there were associations between cancer sites (esophagus, stomach, colo-rectum, liver, pancreas, lung and breast) and various lifestyle factors. In the past 10 years, a hospital-based case-control study at Aichi Cancer Center provided valuable evidence of gene-environment interaction on the development of cancer [i.e., the effects of aldehyde dehydrogenase-2 (ALDH2) polymorphism and heavy alcohol drinking on esophageal cancer, ALDH2 polymorphism and smoking on lung cancer, methylenetetrahydrofolate reductase polymorphism and heavy alcohol drinking on pancreatic cancer]. The database with stored DNA was also used and identified seven loci containing significant but low-penetrance polymorphisms associated with the development of breast cancer. These findings together with established risk factors are likely to be useful to predict personalized breast cancer risk in East Asian women. In 2005, the Japan Multi-Institution Collaborative Cohort (J-MICC) study was launched to elucidate gene-environment interactions as well as to confirm preclinical diagnostic biomarkers of cancer. J-MICC, which has recruited 92,000 healthy individuals by the end of 2012, will follow the individuals until 2025.

Effects of mineral supplementation on liver cirrhotic/cancer male patients

The aim of the present study was to compare the levels of essential trace and toxic elements in biological samples (blood and serum) of male liver cirrhotic/cancer patients (n = 144), of age groups 30-50 years, before and after 60 days treatment with mineral supplementation. For comparison purposes, the same biological samples were also collected from healthy male subjects (n = 120) of the same age groups. The biological samples were oxidized by 65 % HNO₃/30 % H₂O₂ (2:1) in a microwave oven. The digests of all biological samples were analyzed for arsenic (As), cadmium (Cd), selenium (Se), and zinc (Zn) by electrothermal atomic absorption spectrometry. The levels of Se and Zn were lower in liver cirrhotic/cancer patients as compared to healthy individuals (p < 0.001). The patients with liver cirrhosis/cancer have twofold higher As and Cd levels in biological samples as compared to age-matched referents. Moreover, a negative correlation was observed between essential and toxic elements. The pathogenesis of liver cirrhosis/cancer has been associated with changes in the balance of certain essential trace and toxic elements. The study confirms that oral supplements of Se and Zn produce metabolic effects in patients with liver cirrhosis/cancer. It was observed that the status of essential trace elements, Se and Zn, was improved in biological samples of all patients after 60 days of treatment with mineral supplementation.

Risk of hepatocellular carcinoma in workers exposed to chemicals

CONTEXT

Studies on experimental animals have shown liver is a common target of chemical carcinogens; this might suggest that occupational exposure to chemicals is another risk factor for HCC. However, the relationship between occupation and liver cancer has not been extensively studied, with the exception of the known association between vinyl chloride and angiosarcoma of the liver.

EVIDENCE ACQUISITION

A MEDLINE and conventional search of the past 50 years of the medical literature was performed to identify relevant articles on incidence and mechanisms of HCC due to occupational exposure to chemicals. Several important edited books and monographs were also identified and reviewed.

RESULTS

While laboratory data clearly indicate that the liver is an important target of chemical carcinogenesis, epidemiological studies provide very limited evidence on occupational risk factors for HCC. Nevertheless, we found some case reports and epidemiological data showing a moderately increased risk of HCC development in people exposed to vinyl chloride, organic solvents, pesticides, polychlorinated biphenyls, and arsenic.

CONCLUSIONS

Occupational exposure to chemicals may be another risk factor for HCC development, but the interpretation of currently available findings is limited by the small number of studies, questionable accuracy of the diagnosis of liver cancer, and potential confounding or modifying factors such as chronic hepatitis virus infection and alcohol consumption. Further relevant investigations are required for clarifying the actual contribution of occupational exposure to chemicals in HCC development.

Development of a prediction model for 10-year risk of hepatocellular carcinoma in middle-aged Japanese: the Japan Public Health Center-based Prospective Study Cohort II

OBJECTIVE

The purpose of the present study was to develop a risk estimation model for the 10-year risk of hepatocellular carcinoma (HCC) that could be easily used in a general population to aid in the prevention of HCC.

METHODS

Our prediction model was derived from data obtained on 17,654 Japanese aged 40 to 69 years who participated in health checkups (follow-up: 1993-2006). Cox proportional hazards regression was applied to obtain coefficients for each predictor.

RESULTS

During follow-up, a total of 104 cases of HCC were newly diagnosed. After checking the model fit, we incorporated age, sex, alcohol consumption, body mass index, diabetes, coffee consumption, and hepatitis B and C virus infection into the prediction model. The model showed satisfactory discrimination (Harrell's c-index=0.94) and was well calibrated (the overall observed/expected ratio=1.03, 95% confidence interval=0.83-1.29). We also developed a simple risk scoring system. Those subjects with total scores of 17 or more under this system (score range: -1 to 19) had an estimated 10-year HCC risk of over 90%; those with 4 points or less had an estimated risk of less than 0.1%.

CONCLUSION

We developed a simple 10-year risk prediction model for HCC in the Japanese general population as a public education tool.

The risk of cancer in people with diabetes and chronic kidney disease

BACKGROUND

Diabetes and chronic kidney disease (CKD) are both associated with an increased risk of cancer but it is unclear whether diabetes complicated by CKD further augments an individual's cancer risk. The aim of our study was to determine the association of CKD [defined as an estimated glomerular filtration rate (eGFR) < 60 mL/min] with the overall and site-specific risks of incident cancers among individuals with Type 2 diabetes.

METHODS

Cox proportional hazard regression models and competing risk analyses were used to examine the univariate and multivariate adjusted associations between reduced kidney function and the overall and site-specific risks of cancer in participants enrolled in the Action in Diabetes and Vascular disease: Preterax and Diamicron MR controlled evaluation (ADVANCE) trial.

RESULTS

Over a median follow-up of 5.0 years, 700 malignant neoplasms occurred in the 11 140 (6.4%) participants. There was no increase in overall cancer risk [adjusted hazard ratio: 1.07 (95% confidence interval: 0.89-1.29, P = 0.50)] or site-specific cancer risk for individuals with CKD (defined as eGFR < 60 mL/min) compared to those without CKD at baseline. These results were robust to multiple methods and thresholds used to estimate CKD.

CONCLUSIONS

Mild to moderate CKD does not increase the risk of cancer in people with Type 2 diabetes. ADVANCE is registered with ClincalTrial.gov (number NCT00145925).

Comparative study of liver cancer patients in arsenic exposed and non-exposed areas of Pakistan

The investigated data shows that arsenic (As) in drinking water is associated with increased mortality from different types of cancers including liver cancer. In this study, blood and scalp hair samples of male liver cancer patients and healthy referents belonging to As exposed areas of Sindh Pakistan were analyzed for As contents. The As levels in drinking water of understudy area showed that sections of this population was exposed to 3-15-folds higher concentrations of As than permissible limit. For comparative purposes, blood and scalp hair samples of matched cancerous patient as referent patients belonging to big city (Hyderabad) who have used municipal treated water with low As levels <10 μg/L were also collected. The results of this study showed that the average As concentration was higher in the blood and scalp hair of exposed and non-exposed referent cancer patients as compared to referents (p < 001). The exposed cancerous patients have twofolds higher As level in both biological samples as related to non-exposed case matched cancerous male subjects.

Cigarette smoking and esophageal cancer risk: an evaluation based on a systematic review of epidemiologic evidence among the Japanese population

OBJECTIVE

Although cigarette smoking is considered as an important risk factor for esophageal cancer, the magnitude of the association might be varied among geographic areas. Therefore, we reviewed epidemiologic studies on the association between cigarette smoking and esophageal cancer among the Japanese population.

METHODS

Original articles were obtained from MEDLINE searched using PubMed or from searches of the Ichushi database, complemented by manual searches. Evaluation of associations was based on the strength of evidence ('convincing', 'probable', 'possible' or 'insufficient') and the magnitude of association ('strong', 'moderate', 'weak' or 'no association'), together with biological plausibility as previously evaluated by the International Agency for Research on Cancer.

RESULTS

We identified four cohort studies and 11 case-control studies. All cohort studies and eight case-control studies showed strong positive associations between esophageal cancer and cigarette smoking. All cohort studies and five case-control studies showed that cigarette smoking had dose-response relationships with esophageal cancer. Meta-analysis of 12 studies indicated that the summary estimate for ever smokers relative to never smokers was 3.01 (95% confidence interval: 2.30-3.94). Summary relative risk for current and former smokers relative to never smokers was 3.73 (2.16-6.43) and 2.21 (1.60-3.06), respectively.

CONCLUSIONS

We conclude that there is convincing evidence that cigarette smoking strongly increases the risk of esophageal cancer in the Japanese population.

The role for estrogen receptor-alpha and prolactin receptor in sex-dependent DEN-induced liver tumorigenesis

Mice treated neonatally with diethylnitrosamine (DEN) develop liver tumors in a male-dominant manner, reflecting the male bias in human hepatocellular carcinoma. Evidence suggests that estrogen, androgen, prolactin (PRL) and growth hormone (GH) modify liver tumorigenesis. We determined the roles of estrogen receptor-α (ERα) and prolactin receptor (PRLR) using receptor null mice, ERαKO (C57Bl/6J) and PRLR-KO (129Ola-X-C57BL/6), in the neonatal-DEN model of liver tumorigenesis. In both mouse strains, females had reduced tumorigenesis compared with males (P < 0.01), regardless of ERα or PRLR status. Tumorigenesis was not affected by ovariectomy in C57Bl/6J mice but it was increased by ovariectomy in the mixed strain, 129Ola-X-C57BL/6, regardless of PRLR status. ERαKO males had 47% fewer tumors than ERα wild-type males (P < 0.01). On the other hand, estradiol treatment protected against tumorigenesis in males only in the presence of ERα. As evidenced by liver gene expression, lack of ERα did not alter the pattern of GH secretion in males but resulted in the male GH pattern in females. These observations indicate that ERα is not required for lower tumorigenesis in females, but it is required for the protective effects of exogenously delivered estradiol. Unexpectedly, the results indicate that ERα plays a role in promotion of liver tumors in males. In addition, it can be concluded that sex differences in liver tumorigenesis cannot be explained by the sexually dimorphic pattern of GH secretion. The results also rule out PRL as the mediator of the protective effect of the ovaries.

Alcohol drinking and esophageal cancer risk: an evaluation based on a systematic review of epidemiologic evidence among the Japanese population

Although alcohol drinking is considered as an important risk factor for esophageal cancer, the magnitude of the association might be varied among geographic areas. Therefore, we reviewed epidemiologic studies on the association between alcohol drinking and esophageal cancer among the Japanese population. Original data were obtained from MEDLINE, searched using PubMed or from searches of the Ichushi database, complemented with manual searches. Evaluation of associations was based on the strength of evidence ('convincing', 'probable', 'possible' or 'insufficient') and the magnitude of association ('strong', 'moderate', 'weak' or 'no association'), together with biological plausibility as previously evaluated by the International Agency of Research on Cancer. We identified four cohort studies and nine case-control studies. All cohort studies and case-control studies showed strong positive associations between esophageal cancer and alcohol drinking. All cohort studies and six case-control studies showed that alcohol drinking had the dose- or frequency-response relationships with esophageal cancer. In addition, four case-control studies showed that acetaldehyde dehydrogenase Glu504Lys polymorphism had strong effect modification with alcohol drinking. We conclude that there is convincing evidence that alcohol drinking increases the risk of esophageal cancer in the Japanese population.

Psychosocial issues and mental health treatment recommendations for patients with hepatitis C

BACKGROUND

Mental health needs of patients with HCV are increasingly being addressed in medical contexts.

OBJECTIVE

The authors review the psychosocial issues relevant to patients with hepatitis C and provide mental health treatment recommendations.

FINDINGS

Patients with HCV are faced with a number of challenges, including adjustment to a chronic medical illness, management of symptoms and treatment side effects, and making and maintaining lifestyle changes. Given these issues, mental health clinicians have the opportunity to make a significant contribution to patient care.

CONCLUSION

After reviewing the relevant research on these psychosocial issues, the authors have identified areas in which clinicians can intervene; these include adjustment to having a chronic medical illness, coping with stigma and relationship changes, management of side effects, and implementing healthy lifestyle changes.

Interaction between cytochrome P450 1A2 genetic polymorphism and cigarette smoking on the risk of hepatocellular carcinoma in a Japanese population

Limited epidemiological evidence suggests that genetic polymorphisms of drug-metabolizing enzymes such as cytochrome P450 (CYP), glutathione S-transferase (GST) and N-acetyltransferase (NAT) may be involved in tobacco-related hepatocarcinogenesis. We conducted a case-control study, including 209 incident cases with hepatocellular carcinoma (HCC) and two different control groups [275 hospital controls and 381 patients with chronic liver disease (CLD) without HCC], to investigate whether CYP1A1, CYP1A2, CYP2A6, CYP2E1, GSTM1 and NAT2 polymorphisms are related to the risk of HCC with any interaction with cigarette smoking. Overall, no significant associations with HCC were observed for any genotypes against either control group. However, we found a significant interaction (P = 0.0045) between CYP1A2 -3860G>A polymorphism and current smoking on HCC risk when we compared HCC cases with CLD patients; adjusted odds ratios [ORs; and 95% confidence intervals (CIs)] for G/A and A/A genotypes relative to G/G genotype were 0.28 (0.12-0.66) and 0.18 (0.04-0.94), respectively, among current smokers (P trend = 0.002), as compared with 1.28 (0.80-2.06) and 0.76 (0.34-1.71), respectively, among never/former smokers (P trend = 0.96). Similarly, in CYP1A2 G/G genotype, significant risk increase was observed for current smoking (OR = 4.08, 95% CI = 2.02-8.25) or more recent cigarette use (e.g. pack-years during last 5 years, P trend = 0.0003) but not in G/A and A/A genotypes combined (OR for current smoking = 1.39, 95% CI = 0.63-3.03; P trend for pack-years during last 5 years = 0.40). These results suggest that the CYP1A2 -3860G>A polymorphism modifies the smoking-related HCC risk among CLD patients.

Case-control study on cigarette smoking and the risk of hepatocellular carcinoma among Japanese

Emerging epidemiologic data suggest that cigarette smoking may increase the risk of hepatocellular carcinoma (HCC), yet considerable controversies (e.g. inconsistent dose-response relationships) still exist with this association. We examined whether smoking was associated with HCC risk in a case-control study including 209 incident HCC cases and two different control groups (256 hospital controls and 381 patients with chronic liver disease [CLD] without HCC). Comparison of HCC cases with CLD patients, but not with hospital controls, demonstrated a significantly increased risk of HCC for current smokers. After adjustment for sex, age, heavy drinking history and hepatitis virus markers, odds ratios (and 95% confidence intervals) for former and current smokers relative to never smokers were 1.0 (0.6-1.7) and 2.5 (1.4-4.6), respectively, against CLD patients, as compared with 0.8 (0.3-2.3) and 1.8 (0.6-5.1), respectively, against hospital controls. In terms of pack-years during lifetime, dose-response relationship was not evident against either control group (P trend = 0.43), but it became clearer for more recent cigarette use among CLD patients. For example, regarding cumulative cigarette consumption during the last 5 years, adjusted odds ratios (and 95% confidence intervals) for 1-4 and 5+ pack-years relative to no use were 1.9 (1.1-3.6) and 2.8 (1.5-5.2) (P trend = 0.003), respectively. These results suggest that cigarette smoking may play a crucial role in the late stage of HCC development and that CLD patients may benefit from their earliest smoking cessation.

Incidental detection of cancers and other non-cardiac abnormalities on coronary multislice computed tomography

The investigators prospectively examined 625 consecutive patients who underwent coronary multislice computed tomography (MSCT) for suspected coronary artery disease (CAD) and evaluated the presence or absence of cancers and other noncardiac abnormalities on the original transverse sectional images of MSCT. Eight patients with known cancers were excluded from the analysis. The remaining 617 patients (344 men, 273 women; mean age 66 +/- 12 years) were analyzed. Cancers were found in 7 patients (1.13%) on the multislice computed tomographic images, including 4 lung cancers (0.65%), 2 thyroid cancers (0.32%), and 1 hepatic cancer (0.16%). In addition, nonmalignant abnormalities (nodules, tumors, or lymphadenopathies) were also found in 142 patients (23.01%), consisting of 58 postinflammatory lung nodules (9.40%), 49 hepatic cysts or hemangiomas (7.94%), 18 benign thyroid tumors (2.92%), 12 mediastinal lymphadenopathies (1.94%), 4 benign mammary gland tumors (0.65%), and 1 esophageal submucosal tumor (0.16%). In conclusion, cancers and other noncardiac abnormalities are often found in patients who undergo coronary MSCT for suspected CAD. Because patients who undergo coronary MSCT for suspected CAD are mostly elderly and therefore may have unrecognized cancers or other noncardiac abnormalities, care should thus be taken not to overlook these abnormalities when analyzing the multislice computed tomographic images.