Risk factors for cholangiocarcinoma in the lower part of Northeast Thailand: a hospital-based case-control study

The Global Burden of Early-Onset Biliary Tract Cancer: Insight From the Global Burden of Disease Study 2019

Backgrounds/objectives

The escalating incidence of early-onset gastrointestinal cancers is becoming a primary global health concern. Biliary tract cancer (BTC) has been relatively understudied in this regard. We conducted an epidemiological study regarding the burden of this condition.

Methods

We utilized data from the Global Burden of Disease Study 2019 to investigate the temporal trends in early-onset BTC (EOBTC), encompassing the estimation of frequencies and age-standardized rates (ASRs) of EOBTC incidence, mortality, and disability-adjusted life-years (DALYs), from 2010 to 2019.

Results

EOBTC constituted nearly 7%of all BTC cases worldwide. The incidence rates of EOBTC decreased significantly in most regions, except in the Eastern Mediterranean (annual percentage change +1.04 %), where the incidence is rising. Stratified by the sociodemographic index (SDI), countries with low middle SDI (annual percentage change +0.5 %) show increasing incidence of EOBTC. The ASR of death and DALYs decreased in most regions. The ASR of EOBTC-related death and disability attributable to high body mass index increased in most regions, with the highest increase in Southeast Asia and low, middle SDI strata.

Conclusions

There was a reduction in the burden of EOBTC globally, except for Eastern Mediterranean countries and low-middle SDI countries.

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.

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.

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.

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.

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.

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.

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.

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.

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.

Family History of Cancer and Risk of Biliary Tract Cancers: Results from the Biliary Tract Cancers Pooling Project

Background: Although some familial cancer syndromes include biliary tract cancers (BTCs; cancers of the gallbladder, intrahepatic and extrahepatic bile ducts, and ampulla of Vater), the few studies that have examined the relationships between family history of cancer (FHC) and BTCs have reported inconclusive findings. The objective of this study was to investigate the associations of FHC with risk of BTC in the Biliary Tract Cancers Pooling Project (BiTCaPP).Methods: We used Cox proportional hazards regressions models to estimate HRs and 95% confidence intervals for associations between FHC (any, first-degree, in female relative, in male relative, relative with gastrointestinal cancer, and relative with hormonally related cancer) and BTC risk by anatomic site within the biliary tract, adjusting for sex and race/ethnicity. Sensitivity analyses were conducted that restricted to studies reporting cholecystectomy data and to people without a history of cholecystectomy.Results: Data on FHC were available from 12 prospective studies within BiTCaPP, which collectively contributed 2,246 cases (729 gallbladder, 345 intrahepatic and 615 extrahepatic bile duct, and 385 ampulla of Vater cancers) with 21,706,107 person-years of follow-up. A marginal, inverse association between FHC and gallbladder cancer was driven to the null when analysis was restricted to studies reporting cholecystectomy data and to people without a history of cholecystectomy. FHC was not associated with risk of BTC at the other anatomic sites.Conclusions: These findings do not support an association between FHC and BTCs.Impact: In a study of 1.5 million people, FHC is not a risk factor for BTCs. Cancer Epidemiol Biomarkers Prev; 27(3); 348-51. ©2018 AACR.

Evaluation of Cholangiocarcinoma Risk and its Related Factors in Wetland Geographical Communities of Ubon Ratchathani, Thailand

Wetland geographical areas have a higher incidence of Opisthorchis viverrini-associated cholangiocarcinoma (CCA), confirmed by data from geographic information systems, than other areas. Behavioral data also indicate that people in these areas traditionally eat uncooked freshwater fish dishes, a vehicle for O. viverrini infection. The best approach to reducing CCA incidence is decreasing risk factors together with behavior alteration. Evaluation of CCA risk and its related factors are first needed for planning the prevention and control programs in the future. We therefore aimed to evaluate the CCA risk and explore its related factors among people in wetland communities of Ubon Ratchathani, Thailand. A cross-sectional study was conducted between July and August 2014. In total 906 participants, with informed consent, completed questionnaires. Overall risk of CCA was determined by multiplying odds ratios (ORs) of the risk factors for CCA from literature reviews. A mean score of 5.95 was applied as the cut-off point. Assessment of factors related to overall risk of CCA was accomplished using conditional logistic regression. Of all participants, 60.15% had a high level of the overall risk of CCA. Factors related to the overall risk of CCA were gender (<0.001), marital status (<0.001), perceived susceptibility (p=0.043) and prevention behavior for CCA (<0.001). In conclusion, most participants in this community had a high level of overall risk of CCA. Therefore, integrated prevention and control programs continue to be urgently required.

Surveillance of Populations at Risk of Cholangiocarcinoma Development in Rural Communities of Thailand Using the Korat-CCA Verbal Screening Test

Cholangiocarcinoma (CCA) is a serious problem in Thailand, particularly in the northeastern region. Active surveillance in rural communities with an appropriat low-cost screening tool is required to facilitate early detection. Therefore, this study aimed to investigate the population at risk of CCA in Bua Yai district, Nakhon Ratchasima province, Northeastern Thailand using the Korat-CCA verbal screening test (KCVST) during June to October 2015. Reliability of KCVST demonstrated a Cronbach alpha coefficient=0.75 Stepwise-multiple regression showed that alcohol consumption was important for CCA screened, followed by agriculture and pesticide use, under-cooked cyprinoid fish consumption, praziquantel use, naïve northeastern people, opisthorchiasis, family relatives with CCA, and cholangitis or cholecystitis or gallstones, respectively. Population at risk for CCA was classified to low risk (63.4%), moderate risk (33.7%), and high risk (1.32%) for CCA. When CCA was screened using ultrasonography, 4 of 32 high risk participants had an abnormal biliary tract with dilated bile ducts. This study indicates that KCVST is a potential useful too which decrease the cost of large scale CCA screening.

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.

Association between Liver Fluke Infection and Hepatobiliary Pathological Changes: A Systematic Review and Meta-Analysis

OBJECTIVE

To provide information about the role of liver fluke infection as a risk factor for hepatobiliary pathological changes and promote awareness among the people living in endemic areas, a systematic review and meta-analysis based on published studies was conducted to examine the association between liver fluke infection and hepatobiliary pathological changes.

METHODS

Relevant original literature was searched in multiple literature databases, including PubMed, Cochrane, Clinical Evidence, Trip Database, Clinical Trials, Current Controlled Trials, Web of Science, the China National Knowledge Infrastructure (CNKI) database, and the Wanfang academic journal full-text database. Studies were selected based on strict screening with inclusion and exclusion criteria. Tests of heterogeneity, sensitivity and publication bias were performed with the Review Manager software, version 5.3, and meta-regression analyses were performed with the Stata software, version 11.0 (Stata Corporation, College Station, TX, USA). Pooled risk ratios (RRs) and odds ratios (ORs) with their 95% confidence intervals (95% CIs) were calculated and used to evaluate the risk of hepatobiliary pathological changes resulting from liver fluke infection. Linear trend analyses were conducted to determine the dose-response relationship using IBM SPSS Statistics 20.0.

RESULT

A total of 36 studies were included in the meta-analysis. Significant associations were found between liver fluke infection and cholangitis or cholecystitis (RR: 7.80, P<0.001; OR: 15.98, P<0.001), cholelithiasis (RR: 2.42, P = 0.03; OR: 4.96, P = 0.03), hepatocellular carcinoma (OR: 4.69, P<0.001) and cholangiocarcinoma (RR: 10.43, P<0.001; OR: 4.37, P<0.001). In addition, heavier infection was significantly associated with higher incidence of hepatobiliary pathological changes (P<0.05). However, cirrhosis was not significantly associated with liver fluke infection (RR: 3.50, P = 0.06; OR: 5.79, P = 0.08). The statistical heterogeneity was significant, no significant difference was observed in the sensitivity analysis, and no publication bias was found.

CONCLUSION

The meta-analysis found that liver fluke infection was significantly associated with cholangitis, cholecystitis, cholelithiasis, hepatocellular carcinoma and cholangiocarcinoma and that more severe infection was associated with higher incidence. However, the association between liver fluke infection and cirrhosis was not significant.

Analysis of different ways of drainage for obstructive jaundice caused by hilar cholangiocarcinoma

OBJECTIVE

To evaluate the prognosis of different ways of drainage for patients with obstructive jaundice caused by hilar cholangiocarcinoma.

MATERIALS AND METHODS

During the period of January 2006- March 2012, percutaneous transhepatic catheter drainage (PTCD)/ percutaneous transhepatic biliary stenting (PTBS) were performed for 89 patients. According to percutaneous transhepatic cholangiography (PTC), external drainage was selected if the region of obstruction could not be passed by guide wire or a metallic stent was inserted if it could. External drainage was the first choice if infection was diagnosed before the procedure, and a metallic stent was inserted in one week after the infection was under control. Selection by new infections, the degree of bilirubin decrease, the change of ALT, the time of recurrence of obstruction, and the survival time of patients as the parameters was conducted to evaluate the methods of different interventional treatments regarding prognosis of patients with hilar obstruction caused by hilar cholangiocarcinoma.

RESULTS

PTCD was conducted in 6 patients and PTBS in 7 (p<0.05). Reduction of bilirubin levels and ALT levels was obvious after the procedures (p<0.05). The average survival time with PTCD was 161 days and with PTBS was 243 days (p<0.05).

CONCLUSIONS

With both drainage procedures for obstructive jaundice caused by hilar cholangiocarcinoma improvement in liver function was obvious. PTBS was found to be better than PTCD for prolonging the patient survival.

An interleukin-6 receptor polymorphism is associated with opisthorchiasis-linked cholangiocarcinoma risk in Thailand

The cholangiocarcinoma (CCA) is a relatively rare cancer worldwide but it is highly prevalent in Thailand where the liver fluke, Opisthorchis viverrini is endemic. There are reports that interleukin 6 (IL-6) may play an important role in the pathogenesis of opisthorchiasis associated CCA. Functionally, IL-6 can act on target cells through its receptor, IL-6R, and IL-6R polymorphisms may affect the functional activity of IL-6 leading to susceptibility to cholangiocarcinogenesis. Therefore, we assessed the association of the 48892 A/C (Asp358Ala) polymorphism in exon 9 of the IL-6R gene in 79 CCA cases compared to 80 healthy controls using the PCR- RFLP technique. The results showed significant differences between CCA cases and controls in overall genotype (p=0.001) and allele frequencies (p=0.0002). Chi-square for trend test revealed a significant association between genotype and CCA susceptibility (p=0.0002). The odds ratios (ORs) for genotype were 0.283 (95% CI=0.131-0.605, AC vs. AA; p=0.0003) and 0.206 (95% CI=0.196-1.245, CC vs. AA; p=0.0416), the OR for alleles was 0.347 (95% CI=0.187-0.633, allele C vs. allele A; p=0.0002) and that for the carrier C variant was 0.272 (95% CI=0.130-0.564; p=0.0001). This study demonstrated a close association between an IL-6R polymorphism, specifically higher A allele, and cholangiocarcinoma.

Inflammatory bowel disease and risk of cholangiocarcinoma: evidence from a meta-analysis of population-based studies

OBJECTIVE

Patients with inflammatory bowel disease (IBD) have an increased risk of extra-intestinal cancer, whereas its impact on cholangiocarcinoma (CC) remains unknown. The aim of this study was to obtain a reliable estimate of the risk of CC in IBD patients through a meta-analysis of clinical observational studies.

METHODS

Relevant studies were retrieved by searching PUBMED, EMBASE and Web of Science Databases up to Dec 2013. Four population-based case-control and two cohort studies with IBD were identified. Summary relative risk (RR) and its corresponding 95% confidence interval (CI) were calculated using a random-effects model. Potential sources of heterogeneity were detected using subgroup analyses.

RESULTS

The pooled risk estimate indicated IBD patients were at increased risk of CC (RR = 2.63, 95%CI = 1.47-4.72). Moreover, the increased risk of CC was also associated with Crohn's disease (RR = 2.69, 95%CI = 1.59-4.55) and ulcerative colitis (RR = 3.40, 95%CI = 2.50-4.62). In addition, site-specific analyses revealed that IBD patients had an increased risk of intrahepatic CC (ICC) (RR = 2.61, 95%CI = 1.72-3.95) and extrahepatic CC (ECC) (RR = 1.47, 95%CI = 1.10- 1.97).

CONCLUSIONS

This study suggests the risk of CC is significantly increased among IBD patients, especially in ICC cases. Further studies are warranted to enable definite conclusions to be drawn.

Internal-external percutaneous transhepatic biliary drainage for patients with malignant obstructive jaundice

PURPOSE

To evaluate the effect of internal-external percutaneous transhepatic biliary drainage (IEPTBD) for patients with malignant obstructive jaundice.

METHODS

During the period of January 2008 and July 2013, internal-external drainage was performed in 42 patients with malignant obstructive jaundice. During the procedure, if the guide wire could pass through the occlusion and into the duodenum, IEPTBD was performed. External drainage biliary catheter was placed if the occlusion was not crossed. Newly onset of infection, degree of bilirubin decrease and the survival time of patients were selected as parameters to evaluate the effect of IEPTBD.

RESULTS

Twenty newly onset of infection were recorded after procedure and new infectious rate was 47.6%. Sixteen patients with infection (3 before, 13 after drainage) were uncontrolled after procedure, 12 of them (3 before, 9 after drainage) died within 1 month. The mean TBIL levels declined from 299.53 umol/L before drainage to 257.62 umol/L after drainage, while uninfected group decline from 274.86 umol/L to 132.34 umol/Lp (P < 0.5). The median survival time for uninfected group was 107 days, and for infection group was 43 days (P < 0.05).

CONCLUSIONS

The IEPTBD drainage may increase the chance of biliary infection, reduce bile drainage efficiency and decrease the long-term prognosis, and the external drainage is a better choice for patients with malignant obstructive jaundice need to biliary drainage.

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.