Risk factors for cholangiocarcinoma in high-risk area of Thailand: role of lifestyle, diet and methylenetetrahydrofolate reductase polymorphisms

Spatial analysis of cholangiocarcinoma in relation to diabetes mellitus and Opisthorchis viverrini infection in Northeast Thailand

Cholangiocarcinoma (CCA) exhibits a heightened incidence in regions with a high prevalence of Opisthorchis viverrini infection, with previous studies suggesting an association with diabetes mellitus (DM). Our study aimed to investigate the spatial distribution of CCA in relation to O. viverrini infection and DM within high-risk populations in Northeast Thailand. Participants from 20 provinces underwent CCA screening through the Cholangiocarcinoma Screening and Care Program between 2013 and 2019. Health questionnaires collected data on O. viverrini infection and DM, while ultrasonography confirmed CCA diagnoses through histopathology. Multiple zero-inflated Poisson regression, accounting for covariates like age and gender, assessed associations of O. viverrini infection and DM with CCA. Bayesian spatial analysis methods explored spatial relationships. Among 263,588 participants, O. viverrini infection, DM, and CCA prevalence were 32.37%, 8.22%, and 0.36%, respectively. The raw standardized morbidity ratios for CCA was notably elevated in the Northeast's lower and upper regions. Coexistence of O. viverrini infection and DM correlated with CCA, particularly in males and those aged over 60 years, with a distribution along the Chi, Mun, and Songkhram Rivers. Our findings emphasize the association of the spatial distribution of O. viverrini infection and DM with high-risk CCA areas in Northeast Thailand. Thus, prioritizing CCA screening in regions with elevated O. viverrini infection and DM prevalence is recommended.

Clonorchiasis and opisthorchiasis: epidemiology, transmission, clinical features, morbidity, diagnosis, treatment, and control

Clonorchis sinensis, Opisthorchis viverrini, and Opisthorchis felineus are important liver flukes that cause a considerable public health burden in eastern Asia, southeastern Asia, and eastern Europe, respectively. The life cycles are complex, involving humans, animal reservoirs, and two kinds of intermediate hosts. An interplay of biological, cultural, ecological, economic, and social factors drives transmission. Chronic infections are associated with liver and biliary complications, most importantly cholangiocarcinoma. With regard to diagnosis, stool microscopy is widely used in epidemiologic surveys and for individual diagnosis. Immunologic techniques are employed for screening purposes, and molecular techniques facilitate species differentiation in reference laboratories. The mainstay of control is preventive chemotherapy with praziquantel, usually combined with behavioral change through information, education and communication, and environmental control. Tribendimidine, a drug registered in the People's Republic of China for soil-transmitted helminth infections, shows potential against both C. sinensis and O. viverrini and, hence, warrants further clinical development. Novel control approaches include fish vaccine and biological control. Considerable advances have been made using multi-omics which may trigger the development of new interventions. Pressing research needs include mapping the current distribution, disentangling the transmission, accurately estimating the disease burden, and developing new diagnostic and treatment tools, which would aid to optimize control and elimination measures.

Update on the risk factors for opisthorchiasis and cholangiocarcinoma in Thailand

This study aimed to identify the recent risk factors for Opisthorchis viverrini infection and cholangiocarcinoma (CCA) to improve disease prevention. The participants were divided into the following 3 groups based on their health status: healthy control (nonOV and nonCCA), those with O. viverrini infection (OV), and those with CCA. A questionnaire was used to explore their lifestyle and behaviors. Multivariate logistic regression and backward elimination were used to identify the significant risk factors. The results showed that the significant risk factors for both O. viverrini infection and CCA were age>50 years (odd ratio (OR)=8.44, P<0.001, 95% confidence intervals (CI) 2.98-23.90 and OR=43.47, P=0.001, 95% CI 14.71-128.45, respectively) and raw fish consumption (OR=8.48, P< 0.001, 95% CI 3.18-22.63 and OR=3.15, P=0.048, 95% CI 1.01-9.86, respectively). A history of O. viverrini infection was identified as an additional risk factor for CCA (OR=20.93, P=0.011, 95% CI 2.04-215.10). This study provided an update on the risk factors for O. viverrini infection and CCA. Asymptomatic patients with O. viverrini infection, particularly those>50 years old, should be carefully monitored to prevent CCA.

Transcriptomic analysis reveals differential adaptation of colorectal cancer cells to low and acute doses of cisplatin

Over the years, the landscape of cisplatin-based cancer treatment options has undergone continuous transitions. Currently, there is much debate over the optimum dose of cisplatin to be administered to cancer patients. In clinical practice, it can extend from repeated low sub-toxic doses to a few cycles of acute high drug doses. Herein, the molecular understanding of the overall cellular response to such differential doses of cisplatin becomes crucial before any decision making; and it has been a grey area of research. In this study, colorectal cancer (CRC) cells were treated with either- a low sub-toxic dose (LD; 30 µM) or a ten times higher acute dose (HD; 300 µM) of cisplatin, and thereafter, the cellular response was mapped through RNA sequencing followed by transcriptomic analysis. Interestingly, we observed that the tumor cells' response to varying doses of cisplatin is distinctly different, and they activate unique transcriptional programs. The analysis of differentially regulated or uniquely expressed transcripts and corresponding pathways revealed a preferential enrichment of genes associated with chromatin organization, oxidative stress, senescence-associated signaling, and developmentally-active signaling pathways in HD; whereas, modulation of autophagy, protein homeostasis, or differential expression of ABC transporters was primarily enriched in LD. This study is the first of its kind to highlight cellular transcriptomic adaptations to different doses of cisplatin in CRC cells. Consequently, since, protein homeostasis was found to be deeply affected after cisplatin treatment, we further analyzed one of the primary cellular protein homeostatic mechanisms- autophagy. It was activated upon LD, but not HD, and served as a pro-survival strategy through the regulation of oxidative stress. Inhibition of autophagy improved sensitivity to LD. Overall, our study provides a holistic understanding of the distinct molecular signatures induced in CRC cells in response to differential cisplatin doses. These findings might facilitate the design of tailored therapy or appropriate drug dose for enhanced efficacy against CRCs.

Opisthorchis Felineus Infection is a Risk Factor for Cholangiocarcinoma in Western Siberia: A Hospital-based Case-control Study

BACKGROUND

Cholangiocarcinoma (CCA), a fatal bile duct cancer, has a high incidence in Western Siberia, Russian Federation. In addition, Opisthorchis felineus, a bile duct-dwelling trematode liver fluke is highly endemic. Closely related species have been shown to be cancerogenic agents in Asia. We therefore examined the association between O felineus infection and CCA in Western Siberia.

METHODS

We conducted a hospital-based, individually matched case-control study between January 2017 and August 2020 in Tomsk Oblast and Khanty-Mansiysk Autonomous Okrug, Yugra, Russian Federation. Histologically confirmed CCA patients (cases) were compared with matched age, sex, and place of residence hospital controls. The examination of study participants included the diagnosis of current and past O felineus infection, abdominal ultrasonographical assessment, physical examination, and interview on exposures to potential risk factors.

RESULTS

We identified 40 patients with CCA and 160 controls. Exposures to O felineus infection was strongly associated with CCA (odds ratio [OR], 3.9; 95% confidence interval [CI], 1.4-10.8; P = .008). Also, cases reported more often that they were currently or in the past were infected by O felineus compared with controls (OR, 4.03; 95% CI, 1.7-9.5; P = .001). Furthermore, cases reported river fish consumption and fishing habits significantly more often than controls (OR, 5.5; 95% CI, 1.5-19.8; P = .009 and OR, 3.3; 95% CI, 1.4-7.7; P = .005).

CONCLUSIONS

The study results revealed a strong significantly increased risk for CCA development in O felineus-infected individuals. Elaboration of the guidelines on screening programs for early CCA diagnosis, prevention, and treatment is socially important in endemic regions.

Cholangiocarcinoma protective factors in Greater Mekong Subregion: Critical issues for joint planning to sustainably solve regional public health problems

Although Opisthorchis viverrini (OV), lifestyle, and diet co-factors have a relatively high prevalence in the Greater Mekong Subregion (GMS) population, cumulative (0–74) incidence rates of cholangiocarcinoma (CCA) do not reach 5% in this region. Other co-factors must influence, but in this study, we only highlighted positive factors for guiding joint planning to address public health problems at the regional level. Therefore, we aimed to study prevalence and factors associated with CCA incidence focusing only on protective factors. A cross-sectional analytic study was carried out from June to October 2017. Participants with informed consent completed the questionnaires. Descriptive statistics were used to analyze general information. Primary variables were classified into high and low levels by mean. Logistic regression was employed to investigate the correlation between interesting variables and the overall risk level of CCA. The overall prevalence of CCA protective factors of the whole region was knowledge (61.39%), health beliefs (42.32%), prevention behavior (31.93%), and community participation (14.53%). When considering the proportions at a high level, they were 49.53%, 53.72%, 35.37%, and 49.67%, respectively. Significant factors associated with CCA prevention were females with secondary or vocational education, a high level of perceived seriousness and benefits, and community participation. These findings are likely to be helpful for both the public and administrators. First, it can be information for people to be aware of CCA risk. Second, policy-driven authorities at the local or regional level should apply the critical issues from this study for joint planning to sustainably solve regional public health problems.

Global, regional and national burden of primary liver cancer by subtype

INTRODUCTION

Hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (iCCA) are the two main histological subtypes of primary liver cancer. Estimates of the burden of liver cancer by subtype are needed to facilitate development and evaluation of liver cancer control globally. We provide worldwide, regional and national estimates of HCC and iCCA incidence using high-quality data.

METHODS

We used population-based cancer registry data on liver cancer cases by histological subtype from 95 countries to compute the sex- and country-specific distributions of HCC, iCCA and other specified histology. Subtype distributions were applied to estimates of total liver cancer cases for 2018 from the Global Cancer Observatory. Age-standardised incidence rates (ASRs) were calculated.

RESULTS

There were an estimated 826,000 cases of liver cancer globally in 2018: 661,000 HCC (ASR 7.3 cases per 100,000); 123,000 iCCA (ASR 1.4) and 42,000 other specified histology (ASR 0.5). HCC contributed 80% of the world total liver cancer burden followed by iCCA (14.9%) and other specified histology (5.1%). HCC rates were highest in Eastern Asia (ASR 14.8), Northern Africa (ASR 13.2) and South-Eastern Asia (ASR 9.5). Rates of iCCA were highest in South-Eastern Asia (ASR 2.9), Eastern Asia (ASR 2.0), Northern Europe, the Caribbean and Central America and Oceania (ASR all 1.8).

CONCLUSION

We have shown the importance of uncovering the distinct patterns of the major subtypes of liver cancer. The use of these estimates is critical to further develop public health policy to reduce the burden of liver cancer and monitor progress in controlling HCC and iCCA globally.

Effects of Integration of Social Marketing and Health Belief Model for Preventing Cholangiocarcinoma in High-Risk Areas of Thailand: A Community Intervention Study

Introduction/Objective:

To examine the effects of applying social marketing and Health Belief Model (HBM) in preventing cholangiocarcinoma (CCA) in high-risk areas of Thailand.

Methods:

About 2 randomized high-risk areas of CCA from multiple-stage sampling were assigned as study areas. The 150 participants were allocated to the experimental group, which received a 12-week health education program that applied social marketing and HBM. The comparison group received the usual services. Data were collected by a questionnaire created by the researchers. We employed descriptive, inferential statistics (paired t-test and independent t-test) for normal distribution, while Analysis of Covariance (ANCOVA) was used for mean scores differing before the experiment.

Results:

After the experiment, the mean scores of the perceived risk of CCA, perceived severity of CCA, perceived benefits of CCA prevention, perceived barriers to CCA prevention, and correct behaviors of CCA prevention in the experimental group were significantly higher than those before the experiment the .05 level. They were also considerably higher than those of the comparison group at the .05 level.

Conclusion:

This is the first study to integrate social marketing and HBM for CCA prevention. Therefore, formulating policies or measures to prevent disease through public communication will form a model to avoid CCA and create a channel for distributing useful information to the general public.

Association of comorbidity between Opisthorchis viverrini infection and diabetes mellitus in the development of cholangiocarcinoma among a high-risk population, northeastern Thailand

Background

Cholangiocarcinoma (CCA) is a category of lethal hepatobiliary malignancies. Previous studies have found that Opisthorchis viverrini infection and diabetes mellitus (DM) are closely correlated with CCA. However, few studies have discussed the association of CCA with a combination of both O. viverrini infection and DM. This study aimed to assess the correlation of CCA with various combinations of O. viverrini infection and DM among a high-risk population in northeastern Thailand.

Methodology

This study included participants from 20 provinces in northeastern Thailand who had been screened for CCA in the Cholangiocarcinoma Screening and Care Program (CASCAP) between 2013 and 2019. Histories of O. viverrini infection and DM diagnosis were obtained using a health questionnaire. CCA screening used ultrasonography with a definitive diagnosis based on histopathology. Multilevel mixed-effects logistic regression was performed to quantify the association, which is presented as adjusted odds ratios (aOR) and their 95% confidence intervals (CI).

Principal findings

Overall, 263,776 participants were included, of whom 32.4% were infected with O. viverrini, 8.2% were diagnosed with DM, and 2.9% had a history of both O. viverrini infection and DM. The overall rate of CCA was 0.36%. Of those infected with O. viverrini, 0.47% had CCA; among those with DM, 0.59% had CCA and among those infected with O. viverrini and had DM, 0.73% had CCA. Compared with participants who were not infected with O. viverrini and were non-DM, the aOR for those infected with O. viverrini and with DM was 2.36 (95% CI: 1.74–3.21; p-value <0.001).

Conclusions

The combination of O. viverrini infection and DM was highly associated with CCA, and these two conditions had a combined effect on this association that was greater than that of either alone. These findings suggest that CCA screening should have a strong focus on people with a combination of O. viverrini infection and DM.

Northeastern Thailand has a high prevalence of liver fluke infection and increasing incidence of diabetes mellitus. These two conditions are individually risk factors for cholangiocarcinoma in at-risk populations. This study used data from the Cholangiocarcinoma Screening and Care Program to assess association of cholangiocarcinoma (CCA) with combinations of O. viverrini infection history and diabetes mellitus diagnosis in the high-risk area of northeastern Thailand. We found that infection with O. viverrini and a diagnosis of diabetes mellitus (DM) was highly associated with CCA. The risk of CCA in individuals with both of these conditions was higher than in individuals with only one of them.

Effectiveness of Village Health Volunteer Parallel Program for Proactive Action to Reduce Risk Factors for Cholangiocarcinoma in Two High-Risk Countries in the Greater Mekong Subregion

Thailand and Laos were classified as risk areas for cholangiocarcinoma (CCA) in a 2017 assessment in the Greater Mekong Subregion. In 2019, the potential of village health volunteers (VHVs) in both risk areas was developed. The VHVs trained in 2014 (VHV-A) were mentors transferring knowledge of CCA prevention to the trainees (known as VHV-B) in a parallel manner. After that, VHV-Bs in each area educated people to change their behavior. Both parties worked in the same direction to reduce risk factors. In 2020, data were collected after the program was organized in the same populations. The people were aged 30-69 years, whose names were in the civil registration, and had lived in that area for at least five years. Afterward, no less than 172 participants from each location were randomly selected. The research tools used were intervention and questionnaires. Descriptive and inferential statistics were employed for data analysis. After the experiment, all the experimental group's risk factors were significantly different from those of the control group. This study's outcome was an effective program for proactive action in reducing risk factors in the risk areas. Therefore, it should be applied to reduce risk factors for CCA in other regions.

Public health interventions for preventing re-infection of Opisthorchis viverrini: application of the self-efficacy theory and group process in high-prevalent areas of Thailand

OBJECTIVE

To study the effectiveness of public health interventions in preventing Opisthorchis viverrini (OV) re-infection in high-prevalence areas of Thailand.

METHODS

68 people from Sisaket, the province with the second-highest prevalence in Thailand, who tested positive for OV eggs in faeces and took praziquantel before the start of the study, participated. 34 participants were allocated to the experimental group, which received a 12-week public health intervention based on the self-efficacy theory and group process between July and October 2018. The control group received the usual services. Data were collected using a questionnaire with a reliability of 0.84. Faecal examinations using the formalin-ether concentration technique were conducted before and after the experiment. The re-infection rate was analysed after the experimental 12 weeks and after one year. Descriptive and inferential statistics, including paired t-test and independent t-test, were employed for data analysis.

RESULTS

After the experiment, the mean scores of knowledge, perceived self-efficacy, self-efficacy expectation and OV prevention behaviour of the experimental group were significantly higher than before the experiment and also higher than scores of the control group (P < 0.05).

CONCLUSION

The public health intervention is useful. It educated the experimental group about OV, perceived self-efficacy and self-efficacy expectation in changing behaviour to prevent OV re-infection. As a result, no re-infections were observed after the 12-week intervention nor at the one-year follow-up. Public health benefits will be evident if the results are extended to other high-prevalence areas.

Towards Evidence-based Control of Opisthorchis viverrini

Transmission of the carcinogenic liver fluke Opisthorchis viverrini is ongoing across Southeast Asia. Endemic countries within the region are in different stages of achieving control. However, evidence on which interventions are the most effective for reducing parasite transmission, and the resulting liver cancer, is currently lacking. Quantitative modelling can be used to evaluate different control measures against O. viverrini and assist the design of clinical trials. In this article we evaluate the epidemiological parameters that underpin models of O. viverrini and the data necessary for their estimation, with the aim of developing evidence-based strategies for parasite control at a national or regional level.

Genetic Differentiation of Opisthorchis-Like Eggs in Northern Thailand Using Stool Specimens Under National Strategic Plan to Control Liver Fluke Infection and Cholangiocarcinoma

Liver fluke infection caused by Opisthorchis viverrini is recognized as a potential risk factor for cholangiocarcinoma (CCA). The National Strategic Plan to Control Liver Fluke Infection and Cholangiocarcinoma has implemented microscopic-based stool examination screening. However, eggs of O. viverrini and minute intestinal flukes (MIFs) are nearly morphologically similar and could result in inaccurate O. viverrini diagnosis. Stool specimens were collected from eight districts of Chiang Mai Province in northern Thailand. Opisthorchis-like eggs were identified with the Kato-Katz technique and differentiated for O. viverrini and MIFs using molecular study by PCR and PCR-restriction fragment length polymorphism targeting the internal transcribed spacer 2 (ITS2) gene. Prevalence of Opisthorchis-like eggs was 5.9% from a total of 9,570 specimens. From PCR assays, all liver flukes were O. viverrini and all MIFs were Haplorchis taichui. The distribution of species was H. taichui (38.2%), O. viverrini (10.5%), coinfection of H. taichui and O. viverrini (37.2%), and 14.1% were negative from PCR. Totally, H. taichui was found in 75.4% of infections from Opisthorchis-like specimens. ITS2 nucleotide sequencing analysis showed a single variant of O. viverrini with no variation and two variants of H. taichui. This study first revealed the genetic background of Opisthorchis-like eggs in northern Thailand. Minute intestinal flukes are occasionally misdiagnosed as O. viverrini leading to misinterpretation and overestimation of the burden of O. viverrini infection. Molecular diagnosis such as PCR could effectively discriminate species of Opisthorchis-like eggs and help shape the robustness of epidemiological data to control liver fluke infection and raise awareness of other risk factors for CCA.

Spatial analysis of hepatobiliary abnormalities in a population at high-risk of cholangiocarcinoma in Thailand

Cholangiocarcinoma (CCA) is a serious health challenge with low survival prognosis. The liver fluke, Opisthorchis viverrini, plays a role in the aetiology of CCA, through hepatobiliary abnormalities: liver mass (LM), bile duct dilation, and periductal fibrosis (PDF). A population-based CCA screening program, the Cholangiocarcinoma Screening and Care Program, operates in Northeast Thailand. Hepatobiliary abnormalities were identified through ultrasonography. A multivariate zero-inflated, Poisson regression model measured associations between hepatobiliary abnormalities and covariates including age, sex, distance to water resource, and history of O. viverrini infection. Geographic distribution was described using Bayesian spatial analysis methods. Hepatobiliary abnormality prevalence was 38.7%; highest in males aged > 60 years (39.8%). PDF was most prevalent (20.1% of males). The Standardized Morbidity Ratio (SMR) for hepatobiliary abnormalities was highest in the lower and upper parts of the Northeast region. Hepatobiliary abnormalities specifically associated with CCA were also more common in males and those aged over 60 years and distributed along the Chi, Mun, and Songkram Rivers. Our findings demonstrated a high risk of hepatobiliary disorders in Northeast Thailand, likely associated with infection caused by O. viverrini. Screening for CCA and improvement of healthcare facilities to provide better treatment for CCA patients should be prioritized in these high-risk areas.

Vegetable, Fruit Consumption and Risk of Biliary Cancer: Evidence from a Meta-Analysis

BACKGROUND AND OBJECTIVE

This meta-analysis was performed to assess the association between vegetable and fruit (VF) consumption and biliary cancer risk.

METHOD

Relevant studies were identified by a search of MEDLINE and Embase databases. The summary relative risks (RRs) with 95% confidence intervals (CIs) for the highest vs. lowest consumption and dose-response analyses were assessed.

RESULTS

Fourteen studies were eligible. The summary RRs associated with the risk of biliary cancer for the highest vs. lowest were 0.48 (n = 10; 95% CI: 0.22-0.74; Q = 68.27, P_{heterogeneity} < 0.001, I² = 86.8%) for vegetable consumption and 0.47 (n = 13; 95% CI: 0.32-0.61; Q = 32.68, P_{heterogeneity} = 0.001, I² = 63.3%) for fruit consumption. Dose-response associations were analyzed for every 100 gram/day increment: for vegetable (n = 8; RR = 0.31, 95%CI: 0.20-0.47; P_{non-linearity} = 0.35) and for fruit (n = 8; RR = 0.89, 95%CI: 0.66-1.18; P_{non-linearity} = 0.20). There was no publication bias among studies (P_Begg = 0.53, P_Egger = 0.84 for vegetable; P_Begg = 0.95, P_Egger = 0.64 for fruit).

CONCLUSION

This meta-analysis indicated that VF consumption may significantly reduce the risk of biliary cancer. Further well-designed prospective studies are warranted to confirm our findings.

Global Burden of 5 Major Types of Gastrointestinal Cancer

BACKGROUND & AIMS

There were an estimated 4.8 million new cases of gastrointestinal (GI) cancers and 3.4 million related deaths, worldwide, in 2018. GI cancers account for 26% of the global cancer incidence and 35% of all cancer-related deaths. We investigated the global burden from the 5 major GI cancers, as well as geographic and temporal trends in cancer-specific incidence and mortality.

METHODS

Data on primary cancers of the esophagus, stomach, colorectum, liver, and pancreas were extracted from the GLOBOCAN database for the year 2018, as well as from the Cancer Incidence in 5 Continents series, and the World Health Organization mortality database from 1960 onward. Age-standardized incidence and mortality rates were calculated by sex, country, and level of human development.

RESULTS

We observed geographic and temporal variations in incidence and mortality for all 5 types of GI cancers. Esophageal, gastric, and liver cancers were more common in Asia than in other parts of the world, and the burden from colorectal and pancreatic cancers was highest in Europe and North America. There was a uniform decrease in gastric cancer incidence, but an increasing incidence of colorectal cancer in formerly low-incidence regions during the studied time period. We found slight increases in incidence of liver and pancreatic cancer in some high-income regions.

CONCLUSIONS

Although the incidence of some GI cancer types has decreased, this group of malignancies continues to pose major challenges to public health. Primary and secondary prevention measures are important for controlling these malignancies-most importantly reducing consumption of tobacco and alcohol, obesity control, immunizing populations against hepatitis B virus infection, and screening for colorectal cancer.

Opposing Roles of FoxA1 and FoxA3 in Intrahepatic Cholangiocarcinoma Progression

Cholangiocarcinoma (CCA), a malignancy of biliary epithelium, is related to liver stem cell deregulation. FoxAs are a group of transcription factors that play critical roles in liver stem cell differentiation. In this study, the expression levels of FoxAs (i.e., FoxA1, FoxA2 and FoxA3) were detected in intrahepatic CCA tissues and the functions of FoxAs were studied in CCA cell lines. FoxA1 and FoxA2 were mainly localized in the nuclei of normal bile duct (NBD) cells and some of the cancer cells. Low expression of FoxA1 in CCA tissues (72%) was significantly correlated with poor prognosis. FoxA3 expression of CCA cells was localized in the nucleus and cytoplasm, whereas it was slightly detected in NBDs. High expression of FoxA3 in cancer tissues (61%) was significantly related to high metastasis status. These findings suggest the opposing roles of FoxA1 and FoxA3 in CCA. Moreover, the FoxA1-over-expressing CCA cell line exhibited a significant reduction in proliferative and invasive activities compared to control cells. Knockdown of FoxA3 in CCA cells resulted in a significant decrease in proliferative and invasive activities compared with control cells. Taken together, in CCA, FoxA1 is down-regulated and has tumor suppressive roles, whereas FoxA3 is up-regulated and has oncogenic roles.

Sustainable Prevention of Cholangiocarcinoma Through Community Participation in a High-incidence Area in Thailand

Opisthorchiasis and cholangiocarcinoma (CCA) are major public health problems in Northeast Thailand, especially in Ubon Ratchathani, which are the alluvial plains. Those with poor food habits are mostly at risk of having diseases. This study was a participatory action research (PAR) aimed to define the models/plans for CCA prevention. The samples consisted of 40 community representatives. The data were collected by the PAR method. Qualitative data were analyzed by content analysis. The samples coordinately analyzed and prioritized the problems and presented information to the community. The plans consisted of (1) cultivating the right values and behaviors of eating food safe from CCA in children, (2) supervising the shops not to sell foods that are the main risk factors for CCA, (3) supporting the community leaders to act as good role models to the people, (4) assigning every housewife to cook clean and safe food from CCA, and (5) encouraging the villagers to have knowledge and awareness, which can protect them from CCA. After the community designed these plans, responsible persons were assigned to implement them. Two years later, researchers evaluated the outcome. The average scores on knowledge and attitude toward CCA were significantly higher than before implementation. For the impact of projects, prevalence of opisthorchiasis in 2016 was significantly lower than that in 2014. CCA prevention by community participation employed a combination of quantitative and qualitative studies. This study has been successful and sustainable since the community has human resources, budget, and appropriate management of the project.

Behavior-related risk factors for opisthorchiasis-associated cholangiocarcinoma among rural people living along the mekong river in five greater mekong subregion countries

Opisthorchiasis-associated cholangiocarcinoma (OV-CCA) is a major public health problem in Greater Mekong Subregion (GMS) Countries, the poorest region in Asia. People in this region have similar traditions or respect the same religion. There is no difference in lifestyle and food culture. Excluding Thailand, publications on risk factors for OV-CCA from the GMS Countries are few, especially data on behavioral risk factors for OV-CCA. Therefore, this study aimed to assess the behavior-related risk factors and to compare the risk of OV-CCA among rural people living along the Mekong River in five GMS countries. It was a cross-sectional analytic study during June and October 2017. All participants with informed consent completed the questionnaires. Descriptive statistics were used to describe the prevalence of risk factors. Odds ratio with 95% confidence intervals were used to compare the risk of OV-CCA. It was found that there were more drinkers than non-drinkers in all areas, except in Vietnam. The highest history of liver fluke infection was found in Cambodia. Praziquantel use and consumption of raw freshwater fish dishes were mostly found in Lao PDR. The highest consumption of nitrosamine-contaminated foodstuffs was found in Ubon Ratchathani, Thailand. The spatial comparison of OV-CCA risk showed that Lao PDR and Ubon Ratchathani were two risk areas when compared to Tachileik, Myanmar (a reference area). This study provided the behavior-related risk factors for OV-CCA among people in five GMS Countries which would be a major jigsaw puzzle leading to proactive surveillance for OV-CCA prevention in the future.

Discovery of Serotransferrin Glycoforms: Novel Markers for Diagnosis of Liver Periductal Fibrosis and Prediction of Cholangiocarcinoma

Cholangiocarcinoma (CCA) caused by chronic liver fluke infection is a major public health problem in Northeast Thailand. Identification of CCA risk groups is urgently needed for the control of CCA in this region. Periductal fibrosis (PDF) induced by chronic inflammation of bile ducts is known as a pre-neoplastic lesion of CCA. We aimed to identify the serum CCA and PDF biomarkers using mass spectrometry (UPLC-ESI-QqQ) with multiple reaction mode (MRM) analysis. Here, serum levels of serotransferrin glycoforms at the glycopeptide level were measured in the sera of CCA (n = 100), PDF (n = 50), and healthy control (n = 100) subjects. The results indicated that serotransferrin peptide levels were generally the same between the control and PDF groups, whereas CCA patients had reduced levels. Moreover, 56 serotransferrin glycoforms were detected, with nine increased in CCA compared to control subjects. Among them, the serum levels of four glycoforms were increased in PDF and CCA patients compared to control subjects. In particular, highly sialylated multi-branched glycans of serotransferrin serum were significantly correlated with poor prognosis and tumor stage in CCA patients. Taken together, these glycoforms could be used as risk biomarkers and prognosis and diagnosis markers of CCA.

Association between periductal fibrosis and bile duct dilatation among a population at high risk of cholangiocarcinoma: a cross-sectional study of cholangiocarcinoma screening in Northeast Thailand

OBJECTIVES

To assess associations between periductal fibrosis (PDF) and bile duct dilatation (BDD) in ultrasonography (US) screening of population at risk of cholangiocarcinoma (CCA) due to residence in an endemic area for Opisthorchis viverrini. CCA survival rates are low, and early identification of risk factors is essential. BDD is one symptom that can identify patients at risk of CCA. Detection of PDF by US can also identify at-risk patients, at an earlier stage of CCA development. Identification of association between PDF and BDD will inform screening practices for CCA risk, by increasing the viability of PDF screening for CCA risk.

SETTING

Nine tertiary care hospitals in Northeast Thailand.

DESIGN

Cross-sectional study.

PARTICIPANTS

Study subjects in the Cholangiocarcinoma Screening and Care Program (CASCAP) in Northeast Thailand. CASCAP inclusion criteria are all residents of Northeast Thailand aged ≥40 years. Participants are recruited through CCA screening centres and through primary healthcare units. So far, 394 026 have been enrolled.

METHODS

PDF and BDD were identified through US. PDF was categorised into three groups, PDF1, 2 and 3, depending on their high echo locality in the peripheral, segmental and main bile duct, respectively. Associations between PDF and BDD were determined by adjusted OR and 95% CI using multiple logistic regression.

RESULTS

BDD was found in 6.6% of PDF3, 1.7% of PDF2 and 1.4% of PDF1 cases. Among PDF cases, especially in PDF3, BDD was found in men more than in women (8.9% and 4.6%, respectively). Compared with non-PDF, the association between PDF3 and BDD was highly significant (adjusted OR=5.74, 95% CI 4.57 to 7.21, p<0.001).

CONCLUSIONS

Our findings reveal that there is a relationship between PDF and BDD, which is associated with CCA. Therefore, PDF can also be an indicator for suspected CCA diagnosis through US.

Uncooked fish consumption among those at risk of Opisthorchis viverrini infection in central Thailand

In contrast to northern and northeastern Thailand, central Thailand was believed not to be endemic for Opisthorchis viverrini (OV). Fieldwork conducted in a rural area of central Thailand revealed that the prevalence and incidence were relatively high compared with regional average data. We hypothesized that the behavioural-psycho-social background of the study population might play an important role in the high burden of the infection. As a result, a qualitative study was conducted to highlight potential social determinants of the infection dynamics to gain greater understanding of the risk behaviours and their contexts. A qualitative study using focus group discussion and in-depth interviews was conducted in Na-ngam Village, Chachoengsao Province from 2012-14. Framework analysis was used to explore associations between infection and thematic content. Social influence showed a strong impact on infection dynamics of OV infection. Our results revealed that Koi pla (chopped raw fish salad) remains a popular dish in the community, as the dish itself represents northeastern culture. The cultural norm had been transferred from ancestors to their descendants. Some elders complained that discontinuing the consumption of Koi pla went against old traditions with respect to cultural norms and socialization. In contrast, modern education teaches about hygiene including OV infection risks, and accordingly teenagers and young adults were reported to modify their lifestyles including their eating habits. Children are a potential key to pass knowledge to their parents and school-based education programs can serve as a practical hub for knowledge dissemination. However, health education alone might not lead to behavioural change in other age groups. Therefore, more efforts are needed to support the transformation.

Programmed knockout mutation of liver fluke granulin attenuates virulence of infection-induced hepatobiliary morbidity

Infection with the food-borne liver fluke Opisthorchis viverrini is the principal risk factor (IARC Working Group on the Evaluation of Carcinogenic Risks to Humans, 2012) for cholangiocarcinoma (CCA) in the Lower Mekong River Basin countries including Thailand, Lao PDR, Vietnam and Cambodia. We exploited this link to explore the role of the secreted growth factor termed liver fluke granulin (Ov-GRN-1) in pre-malignant lesions by undertaking programmed CRISPR/Cas9 knockout of the Ov-GRN-1 gene from the liver fluke genome. Deep sequencing of amplicon libraries from genomic DNA of gene-edited parasites revealed Cas9-catalyzed mutations within Ov-GRN-1. Gene editing resulted in rapid depletion of Ov-GRN-1 transcripts and the encoded Ov-GRN-1 protein. Gene-edited parasites colonized the biliary tract of hamsters and developed into adult flukes, but the infection resulted in reduced pathology as evidenced by attenuated biliary hyperplasia and fibrosis. Not only does this report pioneer programmed gene-editing in parasitic flatworms, but also the striking, clinically-relevant pathophysiological phenotype confirms the role for Ov-GRN-1 in virulence morbidity during opisthorchiasis.

Analysis of genetic polymorphism of methylenetetrahydrofolate reductase in a large ethnic Hakka population in southern China

Methylenetetrahydrofolate reductase (MTHFR) catalyzes conversion of methylene tetrahydrofolate to methylte trahydrofolate. MTHFR C677T polymorphism has been regarded as a risk factor for various vascular diseases. Our study aimed to investigate the distribution frequencies of this polymorphism among Hakka population living in southern China. We retrospectively recruited 5102 unrelated Chinese Hakka subjects. MTHFR C677T polymorphism was tested using the polymerase chain reaction (PCR) and DNA sequencing. A total of 2358 males and 2744 females (aged from 10 years to 101 years) were included in this study. In total, 2835 (55.63%) subjects were homozygous for the C allele (CC), 1939 (38.00%) subjects were heterozygous (CT), and 325 (6.37%) subjects were homozygous for the T allele (TT). The allelic frequency of mutant T was 25.37% with 325 individual homozygous for this defective allele resulting in a frequency of about 6.37% for the TT genotype. According to the study results, the overall frequency of MTHFR C677T genotypes did not differ significantly among the gender and age groups. Our study showed the prevalence of MTHFR C677T polymorphism in a large ethnic Hakka population living in southern China. It would be important implications for the primary prevention of various vascular diseases.

Opisthorchiasis with proinflammatory cytokines (IL-1β and TNF-α) polymorphisms influence risk of intrahepatic cholangiocarcinoma in Thailand: a nested case-control study

Background

Chronic inflammation and repeated infection with Opisthorchis viverrini (O. viverrini) induces intrahepatic cholangiocarcinoma (ICC). Inflammatory cytokines such as interleukin (IL) and tumor necrosis factor (TNF) are substances in the immune system that promote inflammation and causes disease to progress. Genes that help express proinflammatory cytokines can affect an individual’s susceptibility to disease, especially in cancer-related chronic inflammation. This study aimed to investigate risk factors for ICC with a focus on opisthorchiasis and polymorphisms of proinflammatory cytokines (IL-1β and TNF-α).

Methods

This study was a nested case-control study within a cohort study. 219 subjects who developed a primary ICC were identified and matched with two non-cancer controls from the same cohort based on sex and age at recruitment (±3 years). An O. viverrini-IgG antibody was assessed using enzyme linked immunosorbent assay. IL-1β and TNF-α polymorphisms were analyzed using a polymerase chain reaction with high resolution melting analysis. Associations between variables and ICC were assessed using conditional logistic regression.

Results

Subjects with a high infection intensity had higher risk of ICC than those who had a low level (OR = 2.1; 95% CI: 1.2–3.9). Subjects with all genotypes of TNF-α (GG, GA, AA) and high infection intensity were significantly related to an increased risk of ICC (p < 0.05).

Conclusions

Polymorphisms of IL-1β and TNF-α are not a risk of ICC, but an individual with O. viverrini infection has an effect on all genotypes of the TNF-α gene that might promote ICC. Primary prevention of ICC in high-risk areas is based on efforts to reduce O. viverrini infection.

Detection of Risk Groups for Carcinogenic Liver Fluke Infection by Verbal Screening Questionnaire Using a Mobile Application

The carcinogenic liver fluke, Opisthorchis viverrini, is a serious health problem in Southeast Asia where infection is associated with cholangiocarcinoma, a major cause of death in Thailand. This cross-sectional study aimed to screen for O. viverrini infection among a Thai rural population of 560 individuals from Nakhon Ratchasima, Khonkaen, and Chaiyaphum provinces with a verbal screening test with a mobile application (OvApp). Faecal samples were also processed with a mini-parasep sf parasite faecal concentrator. The infection rate of O. viverrini was found to be 2.86%. The majority of infections were detected in males aged 41–50, with primary school being their highest education level, and who were engaged in agricultural occupations. In screening for O. viverrini infection, the OvApp had a high sensitivity (87.5%), specificity (94.6%), negative predictive value (98.9%), and accuracy (98.6%). The positive predictive value was 70.0% for the OvApp. The observed agreement was substantial for this application (k-value = 0.64) indicated that it is a potentially useful tool for decreasing the cost of large-scale O. viverrini screening.

Translational Bioinformatics for Cholangiocarcinoma: Opportunities and Challenges

Translational bioinformatics is becoming a driven force and a new scientific paradigm for cancer research in the era of big data. To promote the cross-disciplinary communication and research, we take cholangiocarcinoma as an example to review the present status and the future perspectives of the bioinformatics models applied in cancer study. We first summarize the present application of computational methods to the study of cholangiocarcinoma ranged from pattern recognition of biological data, knowledge based data annotation to systems biological level modeling and clinical translation. Then the future opportunities and challenges about database or knowledge base building, novel model developing and molecular mechanism exploring as well as the intelligent decision supporting system construction for the precision diagnosis, prognosis and treatment of cholangiocarcinoma are discussed.

Thinking beyond Opisthorchis viverrini for risk of cholangiocarcinoma in the lower Mekong region: a systematic review and meta-analysis

Background

Cholangiocarcinoma (CCA) is a fatal bile duct cancer associated with infection by the liver fluke, Opisthorchis viverrini, in the lower Mekong region. Numerous public health interventions have focused on reducing exposure to O. viverrini, but incidence of CCA in the region remains high. While this may indicate the inefficacy of public health interventions due to complex social and cultural factors, it may further indicate other risk factors or interactions with the parasite are important in pathogenesis of CCA. This systematic review aims to provide a comprehensive analysis of described risk factors for CCA in addition to O. viverrini to guide future integrative interventions.

Main body

We searched five international and seven Thai research databases to identify studies relevant to risk factors for CCA in the lower Mekong region. Selected studies were assessed for risk of bias and quality in terms of study design, population, CCA diagnostic methods, and statistical methods. The final 18 included studies reported numerous risk factors which were grouped into behaviors, socioeconomics, diet, genetics, gender, immune response, other infections, and treatment for O. viverrini. Seventeen risk factors were reported by two or more studies and were assessed with random effects models during meta-analysis. This meta-analysis indicates that the combination of alcohol and smoking (OR = 11.1, 95% CI: 5.63–21.92, P <  0.0001) is most significantly associated with increased risk for CCA and is an even greater risk factor than O. viverrini exposure. This analysis also suggests that family history of cancer, consumption of raw cyprinoid fish, consumption of high nitrate foods, and praziquantel treatment are associated with significantly increased risk. These risk factors may have complex relationships with the host, parasite, or pathogenesis of CCA, and many of these risk factors were found to interact with each other in one or more studies.

Conclusions

Our findings suggest that a complex variety of risk factors in addition to O. viverrini infection should be addressed in future public health interventions to reduce CCA in affected regions. In particular, smoking and alcohol use, dietary patterns, and socioeconomic factors should be considered when developing intervention programs to reduce CCA.

Electronic supplementary material

The online version of this article (10.1186/s40249-018-0434-3) contains supplementary material, which is available to authorized users.

Cancer incidence in northern Thailand: Results from six population-based cancer registries 1993-2012

Rapid changes in social and economic development have led to cancer becoming a major cause of national morbidity and mortality in Thailand. Cancer registries have been critical in documenting subnational cancer patterns and transitions in the country; with the establishment of six registries in northern Thailand, a comprehensive assessment of the scale and profile of cancer is now possible in the region. Cancers of the liver, lung, colorectum, breast and cervix were the major cancers 2008-2012, although variations in the profiles of cancer were observed, with a very high incidence of liver cancer seen among males in Phrae, corresponding to one in 11 men developing the disease in a lifetime. Based on data from Lampang and Chiang Mai 1993-2012, rates of lung and cervical cancer incidence have declined, while liver, colorectal and breast cancer incidence have been increasing up to 2012. A more detailed investigation of the incidence trends for specific cancer sites and subtypes at the local level are crucial to the monitoring and evaluation of the cancer control interventions implemented within the Thai national cancer control programme (NCCP). Priority should be given to extend the capacity of the new registries in northern Thailand, ensuring improvement in quality and utilization of the data to drive epidemiologic research and cancer control.

Risk Factors for Cholangiocarcinoma in Thailand: A Systematic Review and Meta-Analysis

Background and objective:

Cholangiocarcinoma remains a serious public health concern in Thailand. While many of the risk factors for cholangiocarcinoma in western countries are well-recognized, it remains unclear whether they are the same in Thailand. We set out to investigate the risk factors for cholangiocarcinoma in Thailand.

Methods:

Starting March 4, 2016, we reviewed studies found using pre-specified keywords on SCOPUS, Pro Quest Science Direct, PubMed, and online public access catalog of Khon Kaen University. Two review authors independently screened studies for inclusion criteria, extracted data, and assessed the studied Risk of Bias. The Newcastle-Ottawa Scale and the Joanna Briggs Institute Critical Appraisal Tools were used to assess the quality of included studies. The risk effects of factors were estimated as a pooled adjusted odds ratio with a 95% confidence interval. The heterogeneity of results was considered using the I-square, Tau-square and Chi-square statistics.

Results:

A strong association was found between cholangiocarcinoma and age, Opisthorchis viverrini infection, eating raw cyprinoid fish, family history of cancer, liquor consumption, and taking praziquantel. There was only a mild association found between eating nitrite-containing foods, fresh vegetables, education, smoking behavior, and sex. No association was found between cholangiocarcinoma and eating fermented fish (Pla-ra), northeastern Thai or Chinese sausage, sticky rice, meat, chewing betel nut, or eating fruit. There were two protective factors including fresh vegetables consumption and education attainment.

Conclusion:

There are unique risk factors of cholangiocarcinoma in Thailand, including age, Opisthorchis viverrini infection, eating raw cyprinoid fish, family history of cancer, liquor consumption, and taking praziquantel.

Systematic review and meta-analysis: cholecystectomy and the risk of cholangiocarcinoma

Studies have reported that cholecystectomy may increase the risk of cholangiocarcinoma. However, this association is controversial. Thus, we conducted a systematic review and meta-analysis to explore the relationship between cholecystectomy and the risk of cholangiocarcinoma. Relevant studies were identified by searching PubMed, EMBASE, ISI Web of Science published before February 2017. We used the random effects model proposed by DerSimonian and Laird to quantify the relationship between cholecystectomy and risk of cholangiocarcinoma. Publication bias was evaluated using funnel plots, Begg's and Egger's tests. Subgroup and sensitivity analyses were performed to validate the stability of the results. 16 articles, comprising 220,376 patients with cholecystectomy and 562,392 healthy controls, were included in our research. Our meta-analysis suggested that the risk of cholangiocarcinoma was significantly higher in the cholecystectomized patients in comparison with healthy controls, with heterogeneity among studies (summary odds ratio [OR] = 0.72; confidence interval [CI] = 0.55-0.90; I² = 69.5%). Additionally, this association was also observed in cohort studies (OR = 0.83; 95% CI = 0.73-0.94) and case-control studies (OR = 0.60; 95% CI = 0.40-0.80). However, When the intrahepatic cholangiocarcinoma and extrahepatic cholangiocarcinoma were analyzed separately, the present study only indicated cholecystectomy was associated with increased the risk of extrahepatic cholangiocarcinoma (OR = 1.19; 95% CI = 0.32-2.05), rather than intrahepatic cholangiocarcinoma (OR = 1.19; 95% CI = 0.32-2.05). In conclusion, cholecystectomy was associated with a significant 54% increase in the risk of cholangiocarcinoma, especially in the extrahepatic cholangiocarcinoma.

Untangling the Complexity of Liver Fluke Infection and Cholangiocarcinoma in NE Thailand Through Transdisciplinary Learning

This study demonstrates how a transdisciplinary learning approach provided new insights for explaining persistent Opisthorchis viverrini infection in northern Thailand, as well as elucidating problems of focusing solely on the parasite as a means of addressing high prevalence of cholangiocarcinoma. Researchers from diverse backgrounds collaborated to design an investigative homestay program for 72 Singaporean and Thai university students in five northeast Thai villages. The students explored how liver fluke infection and potential cholangiocarcinoma development are influenced by local landscape dynamics, aquatic ecology, livelihoods, food culture and health education. Qualitative fieldwork was guided daily by the researchers in a collaborative, co-learning process that led to viewing this health issue as a complex system, influenced by interlinked multidimensional factors. Our transdisciplinary experience has led us to believe that an incomplete understanding of these linkages may reduce the efficacy of interventions. Further, viewing liver fluke infection and cholangiocarcinoma as the same issue is inadvisable. Although O. viverrini infection is an established risk factor for the development of cholangiocarcinoma, multiple factors are known to influence the likelihood of acquiring either. Understanding the importance of the current livelihood transition, landscape modification and the resulting mismatch between local cultures and new socio-ecological settings on cholangiocarcinoma initiation and liver fluke transmission is of critical importance as it may help readjust our view of the respective role of O. viverrini and other socioeconomic risk factors in cholangiocarcinoma etiology and refine intervention strategies. As demonstrated in this study, transdisciplinary approaches have the potential to yield more nuanced perspectives to complex diseases than research that focuses on specific aspects of their epidemiology. They may therefore be valuable when designing effective solutions to context-sensitive diseases such as liver fluke infection and cholangiocarcinoma.

Viewing cellular origin of intrahepatic cholangiocarcinoma from perspective of tumor heterogeneity

Intrahepatic cholangiocarcinoma (ICC) is the second most frequent primary liver malignancy, representing approximately 5%-15% of all cases. ICC is a very heterogeneous tumor from any point of view, including epidemiology, risk factors, morphology, pathology, molecular pathology, growth and clinical features. For a long time, scholar believe that ICC is derived from the intrahepatic bile duct epithelium. Genome-wide, high-throughput technologies have resulted in major advances in understanding the molecular basis of ICC. Recent data have revealed that ICC may be derived from different cell types, including hepatocytes, dysplastic or immature bile duct epithelial cells, pluripotent stem cells (biliary tree stem/progenitor cells) and peribiliary glands cells. Therefore, we hypothesize that different cellular origins may be responsible for the heterogeneity of ICC.

Challenges of liver cancer: Future emerging tools in imaging and urinary biomarkers

Chronic liver disease has become a global health problem as a result of the increasing incidence of viral hepatitis, obesity and alcohol misuse. Over the past three decades, in the United Kingdom alone, deaths from chronic liver disease have increased both in men and in women. Currently, 2.5% of deaths worldwide are attributed to liver disease and projected figures suggest a doubling in hospitalisation and associated mortality by 2020. Chronic liver diseases vary for clinical manifestations and natural history, with some individuals having relatively indolent disease and others with a rapidly progressive course. About 30% of patients affected by hepatitis C has a progressive disease and develop cirrhosis over a 20 years period from the infection, usually 5-10 years after initial medical presentation. The aim of the current therapeutic strategies is preventing the progression from hepatitis to fibrosis and subsequently, cirrhosis. Hepatic steatosis is a risk factor for chronic liver disease and is affecting about the half of patients who abuse alcohol. Moreover non-alcoholic fatty liver disease is part of the metabolic syndrome, associated with obesity, hypertension, type II diabetes mellitus and dyslipidaemia, and a subgroup of patients develops non-alcoholic steatohepatitis and fibrosis with subsequent cirrhosis. The strengths and pitfalls of liver biopsy are discussed and a variety of new techniques to assess liver damage from transient elastography to experimental techniques, such as in vitro urinary nuclear magnetic resonance spectroscopy. Some of the techniques and tests described are already suitable for more widespread clinical application, as is the case with ultrasound-based liver diagnostics, but others, such as urinary metabonomics, requires a period of critical evaluation or development to take them from the research arena to clinical practice.

Association between praziquantel treatment and cholangiocarcinoma: a hospital-based matched case-control study

Background

Infection by the liver fluke, Opisthorchis viverrini, remains an important public health problem in Thailand and has resulted in the highest prevalence of infection and incidence of subsequent cholangiocarcinoma (CCA) in the world. Praziquantel (PZQ) is the antihelminthic drug of choice for treatment. Previous studies in hamsters showed that repeated infection and PZQ treatment could increase the risk of CCA. However, the few available epidemiology studies in humans have shown unclear evidence of an increased risk of CCA with frequency of PZQ intake. The present study investigated the relationship between the number of repeated PZQ treatments and CCA.

Methods

A hospital-based matched case–control study was conducted. All cases and controls were inpatients of a tertiary hospital in Northeast Thailand. During 2012–2014 a total of 210 incident cases of pathologically diagnosed CCA and 840 control subjects were selected from a hospital inpatient database (four controls per case). The four recruited controls were individually matched with CCA cases by gender, age and date of admission. Data were collected in face-to-face interviews using a standardised pre-tested questionnaire. Multivariable conditional logistic regression was used in the analysis of the data.

Results

The frequencies of PZQ usage among the 210 cases and 840 controls were 48.6 vs. 66.0 for never, 32.9 vs. 24.4 for once, 8.6 vs. 4.9 for twice, and 10.0 % vs. 4.8 % for more than twice, respectively. There was a statistically significant dose–response relationship (p < 0.001). Compared with subjects who never used PZQ, those who used the medication once, twice, and more than twice were 1.49, 1.82, and 2.30 times more likely to develop CCA (95 % confidence intervals: 1.02 - 2.20, 0.92 - 3.60, and 1.20 - 4.40). These odds ratios (adjusted ORs) had already been adjusted for the effects of eating raw fish, a family history of cancer, and highest educational attainment. Additional PZQ usage increased the odds of developing CCA by 23.0 % (adjusted OR = 1.23; 95 % CI: 1.07 - 1.43).

Conclusions

The findings show that repeated PZQ treatments are associated with an increased risk of CCA. Paradoxically, this contradicts the common belief that repeated PZQ treatments decrease the risk of CCA. The study also showed a strong association between the number of repeated PZQ treatments and the consumption of raw freshwater fish. This suggests that repeated PZQ treatments may be a surrogate marker of habit of eating raw fish.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-015-1788-6) contains supplementary material, which is available to authorized users.

The concept of lifestyle factors, based on the teaching of avicenna (ibn sina)

According to the definition stated in the beginning of the “Al-Qanun fi al-Tibb” (the Qanun of Medicine); medicine is a science, from which one learns the states of the human body; health and disease and what causes them, in order to preserve good health when it exists, and restore it when it is lacking. Based on this issue, Avicenna believes that medical science belongs to all human without any limitation, and maintenance of health is one of its prime objectives. He states that many disorders are related to errors in the 6 factors, which are essential for maintaining health and preventing diseases. Avicenna described these six essential factors (lifestyle factors) in his masterpiece, Qanun of Medicine, as “Asbab-e-Settah-e-Zaruriah.” Based on the teaching of Avicenna, the first step for maintaining health and approaches to treatment is modification of lifestyle factors, including of nutrition, physical activity, etc.

Genetic and environmental determinants of risk for cholangiocarcinoma in Thailand

Cholangiocarcinoma (CCA) is a difficult cancer to diagnose in the early stage and to treat by curative resection. The incidence of CCA in the northeast of Thailand is the highest in the world. To make progress in detecting a high risk group and in the prevention and detection of CCA, we have been analyzing the risk factors for CCA. Although liver fluke infection is known to be a risk factor, there are patients who are not infected with the liver fluke and not all people infected with the liver fluke will suffer from the disease. Therefore, it is of the utmost importance to analyze the risk factors and the mechanism to prevent the disease and also to detect the disease in its early stage to save patients’ lives. Through collaboration among Thai and Japanese researchers, we analyzed the genetic and environmental determinants of risks for CCA. Also, we have been trying to develop methods to detect the disease in a non-invasive way. Without repeating findings reported in various reviews on CCA, we will first discuss the environmental and genetic determinants of the risks for CCA. Second, we will discuss the properties of CCA, including the etiological agents and the mechanism of cholangiocarcinogenesis, and finally, we will discuss future approaches to prevent and cure CCA from the standpoint of evidence-based medicine. We will discuss these points by including the data from our laboratories. We would like to emphasize the importance of the genetic data, especially whole genome approaches, to understand the properties of CCA, to find a high risk population for CCA and to develop effective preventative methods to stop the carcinogenic steps toward CCA in the near future. In addition, it is of the upmost importance to develop a non-invasive, specific and sensitive method to detect CCA in its early stage for the application of modern medical approaches to help patients with CCA.

Gene-environment interaction involved in cholangiocarcinoma in the Thai population: polymorphisms of DNA repair genes, smoking and use of alcohol

OBJECTIVE

Cholangiocarcinoma (CCA) is the most common malignancy in a Northeast Thai population. Smoking and alcohol drinking are associated with the production of free radical intermediates, which can cause several types of DNA lesions. Reduced repair of these DNA lesions would constitute an important risk factor for cancer development. We therefore examined whether polymorphisms in DNA base-excision repair (BER) genes, XRCC1 G399A and OGG1 C326G, were associated with CCA risk and whether they modified the effect of smoking and alcohol drinking in the Thai population.

DESIGN

A nested case-control study within the cohort study was conducted: 219 participants with primary CCA were each matched with two non-cancer controls from the same cohort on sex, age at recruitment and the presence/absence of Opisthorchis viverrini eggs in stools. Smoking and alcohol consumption were assessed on recruitment. Polymorphisms in BER genes were analysed using a PCR with high-resolution melting analysis. The associations were assessed using conditional logistic regression.

RESULTS

Our results suggest that, in the Thai population, polymorphisms in XRCC1 and OGG1 genes, particularly in combination, are associated with increased susceptibility to CCA, and that their role as modifiers of the effect of smoking and alcohol consumption influences the risk of CCA.

CONCLUSIONS

Better ways of reducing habitual smoking and alcohol consumption, targeted towards subgroups which are genetically susceptible, are recommended. CCA is a multifactorial disease, and a comprehensive approach is needed for its effective prevention. This approach would also have the additional advantage of reducing the onset of other cancers.

STATs profiling reveals predominantly-activated STAT3 in cholangiocarcinoma genesis and progression

BACKGROUND

We investigated the aberrant expression of the STAT family in humans and liver fluke (Opisthorchis viverrini, Ov)-induced hamster cholangiocarcinoma (CCA) tissues.

METHODS

The expression and phosphorylation of STAT1, STAT2, STAT3, STAT4, STAT5a, STAT5b and STAT6 in human hamster CCA tissues were immunohistochemistry-profiled. Localizations of STAT5 in macrophages and lipopolysaccharide (LPS)-induced macrophage-conditioned media mediated STAT3 activation in CCA cells were demonstrated.

RESULTS

The expressions of STAT 1-4 and 6 were detected in the cytoplasm of hyperplastic bile ducts and tumor cells, whereas STAT5a and STAT5b were observed in macrophages and connective tissues surrounding tumor, respectively. The expressions of STAT3 and STAT5b were significantly observed in tumors with a poorer histological differentiation. STAT3 expression was significantly associated with shorter survival of CCA patients and was predominately activated in CCA cell lines. In the CCA-hamsters, STATs expression was gradually increased along the carcinogenesis, especially at 30 days post-infection in which the inflammatory response was markedly observed, showing the correlation between the inflammation and STATs activation. Moreover, LPS-induced macrophage-conditioned media could mediate STAT3 activation in CCA cells.

CONCLUSIONS

STAT3 is the major STAT, which plays roles in the inflammation that contributes to CCA carcinogenesis and progression and may serve as a marker for a poor prognosis of CCA.

Alcohol and liver cancer: a systematic review and meta-analysis of prospective studies

Despite several studies support a positive association between heavy alcohol consumption and liver cancer risk, a consistent dose-risk relationship has not yet been established. We carried out a systematic review and a meta-analysis of the association between alcohol intake and liver cancer occurrence, following the Meta-analysis Of Observational Studies in Epidemiology guidelines. We searched for cohort and nested case-control studies on the general population published before April 2013, using PubMed and EMBASE. Summary meta-analytic relative risks (RRs) were estimated using random-effect models. We included 16 articles (19 cohorts) for a total of 4445 incident cases and 5550 deaths from liver cancer. Compared with non-drinking, the pooled RRs were 0.91 (95% confidence interval, CI, 0.81-1.02) for moderate drinking (< 3 drinks per day) and 1.16 (95% CI, 1.01-1.34) for heavy drinking (≥ 3 drinks per day), with significant heterogeneity among studies. The dose-risk curve suggested a linear relationship with increasing alcohol intake in drinkers, with estimated excess risk of 46% for 50 g of ethanol per day and 66% for 100 g per day. This systematic review suggests a moderate detrimental role of consumption of 3 or more alcoholic drinks per day on liver cancer, and a lack of association with moderate drinking. Our results have to be taken with due caution on account of the possible limitations of the original studies included in the meta-analysis.

Risk factors and classifications of hilar cholangiocarcinoma

Cholangiocarcinoma is the second most common primary malignant tumor of the liver. Perihilar cholangiocarcinoma or Klatskin tumor represents more than 50% of all biliary tract cholangiocarcinomas. A wide range of risk factors have been identified among patients with Perihilar cholangiocarcinoma including advanced age, male gender, primary sclerosing cholangitis, choledochal cysts, cholelithiasis, cholecystitis, parasitic infection (Opisthorchis viverrini and Clonorchis sinensis), inflammatory bowel disease, alcoholic cirrhosis, nonalcoholic cirrhosis, chronic pancreatitis and metabolic syndrome. Various classifications have been used to describe the pathologic and radiologic appearance of cholangiocarcinoma. The three systems most commonly used to evaluate Perihilar cholangiocarcinoma are the Bismuth-Corlette (BC) system, the Memorial Sloan-Kettering Cancer Center and the TNM classification. The BC classification provides preoperative assessment of local spread. The Memorial Sloan-Kettering cancer center proposes a staging system according to three factors related to local tumor extent: the location and extent of bile duct involvement, the presence or absence of portal venous invasion, and the presence or absence of hepatic lobar atrophy. The TNM classification, besides the usual descriptors, tumor, node and metastases, provides additional information concerning the possibility for the residual tumor (R) and the histological grade (G). Recently, in 2011, a new consensus classification for the Perihilar cholangiocarcinoma had been published. The consensus was organised by the European Hepato-Pancreato-Biliary Association which identified the need for a new staging system for this type of tumors. The classification includes information concerning biliary or vascular (portal or arterial) involvement, lymph node status or metastases, but also other essential aspects related to the surgical risk, such as remnant hepatic volume or the possibility of underlying disease.

Asia-Pacific consensus recommendations for endoscopic and interventional management of hilar cholangiocarcinoma

Hilar cholangiocarcinoma (HCCA) is one of the most common types of hepatobiliary cancers reported in the world including Asia-Pacific region. Early HCCA may be completely asymptomatic. When significant hilar obstruction develops, the patient presents with jaundice, pale stools, dark urine, pruritus, abdominal pain, and sometimes fever. Because no single test can establish the definite diagnosis then, a combination of many investigations such as tumor markers, tissue acquisition, computed tomography scan, magnetic resonance imaging/magnetic resonance cholangiopancreatography, endoscopic ultrasonography/intraductal ultrasonography, and advanced cholangioscopy is required. Surgery is the only curative treatment. Unfortunately, the majority of HCCA has a poor prognosis due to their advanced stage on presentation. Although there is no survival advantage, inoperable HCCA managed by palliative drainage may benefit from symptomatic improvement. Currently, there are three techniques of biliary drainage which include endoscopic, percutaneous, and surgical approaches. For nonsurgical approaches, stent is the most preferred device and there are two types of stents i.e. plastic and metal. Type of stent and number of stent for HCCA biliary drainage are subjected to debate because the decision is made under many grounds i.e. volume of liver drainage, life expectancy, expertise of the facility, etc. Recently, radio-frequency ablation and photodynamic therapy are promising techniques that may extend drainage patency. Through a review in the literature and regional data, the Asia-Pacific Working Group for hepatobiliary cancers has developed statements to assist clinicians in diagnosing and managing of HCCA. After voting anonymously using modified Delphi method, all final statements were determined for the level of evidence quality and strength of recommendation.

Opportunities and challenges for selected emerging technologies in cancer epidemiology: mitochondrial, epigenomic, metabolomic, and telomerase profiling

Remarkable progress has been made in the last decade in new methods for biologic measurements using sophisticated technologies that go beyond the established genome, proteome, and gene expression platforms. These methods and technologies create opportunities to enhance cancer epidemiologic studies. In this article, we describe several emerging technologies and evaluate their potential in epidemiologic studies. We review the background, assays, methods, and challenges and offer examples of the use of mitochondrial DNA and copy number assessments, epigenomic profiling (including methylation, histone modification, miRNAs, and chromatin condensation), metabolite profiling (metabolomics), and telomere measurements. We map the volume of literature referring to each one of these measurement tools and the extent to which efforts have been made at knowledge integration (e.g., systematic reviews and meta-analyses). We also clarify strengths and weaknesses of the existing platforms and the range of type of samples that can be tested with each of them. These measurement tools can be used in identifying at-risk populations and providing novel markers of survival and treatment response. Rigorous analytic and validation standards, transparent availability of massive data, and integration in large-scale evidence are essential in fulfilling the potential of these technologies.

Population genetic structuring in Opisthorchis viverrini over various spatial scales in Thailand and Lao PDR

Khon Kaen Province in northeast Thailand is known as a hot spot for opisthorchiasis in Southeast Asia. Preliminary allozyme and mitochondrial DNA haplotype data from within one endemic district in this Province (Ban Phai), indicated substantial genetic variability within Opisthorchis viverrini. Here, we used microsatellite DNA analyses to examine the genetic diversity and population structure of O. viverrini from four geographically close localities in Khon Kaen Province. Genotyping based on 12 microsatellite loci yielded a mean number of alleles per locus that ranged from 2.83 to 3.7 with an expected heterozygosity in Hardy–Weinberg equilibrium of 0.44–0.56. Assessment of population structure by pairwise F_ST analysis showed inter-population differentiation (P<0.05) which indicates population substructuring between these localities. Unique alleles were found in three of four localities with the highest number observed per locality being three. Our results highlight the existence of genetic diversity and population substructuring in O. viverrini over a small spatial scale which is similar to that found at a larger scale. This provides the basis for the investigation of the role of parasite genetic diversity and differentiation in transmission dynamics and control of O. viverrini.

Infection with the liver fluke (Opisthorchis viverrini) is a risk factor for cholangiocarcinoma (CCA), which is highly prevalent in Khon Kaen Province, Thailand. Within this Province, there is considerable variation in the epidemiology of opisthorchiasis among districts. Preliminary allozyme and mitochondrial DNA data indicate that genetic variation in O. viverrini occurs even over a small endemic area within the province. Here, we used microsatellite DNA analyses to examine the population genetic structure of O. viverrini from four geographically close localities. Analyses of adult worms based on 12 microsatellite loci revealed varying levels of genetic diversity and population substructuring between the four localities. Worms originating from one locality (Phu Wiang) had significantly higher genetic diversity than the other three localities. Data on the population genetic structure observed in these localities are similar to those found at a larger geographic scale. This provides background data to further investigate the biological and epidemiological significance of these genetic variants.