Medical risk factors associated with cholangiocarcinoma in Taiwan: a population-based case-control study

Diabetes mellitus and the risk of cholangiocarcinoma: an updated meta-analysis

INTRODUCTION

A number of studies have shown that diabetes mellitus is implicated in susceptibility to several cancers. However, the relationship between diabetes and cholangiocarcinoma remain unclear.

AIM

To quantitatively assess the relationship between diabetes and incidence of cholangiocarcinoma in cohort and case-control studies.

MATERIAL AND METHODS

A literature search was performed for entries from 1996 to 2014 using the PubMed and EMBASE databases. Studies were included if they reported odds ratios (OR) and corresponding 95% CI of cholangiocarcinoma with respect to diabetes mellitus.

RESULTS

Twenty studies met the inclusion criteria, which included fifteen case-control studies and five cohort studies from Asia (n = 11), the United States (n = 5), and Europe (n = 4). Compared with individuals without diabetes, the pooled OR of cholangiocarcinoma was 1.74 (95% CI: 1.62-1.87, p = 0.568 for heterogeneity) for patients with diabetes, ICC (summary RR, 1.93; 95% CI: 1.65-2.25; p = 0.037 for heterogeneity), and ECC (summary RR, 1.66; 95% CI: 1.39-1.98; p = 0.001 for heterogeneity). The funnel plot revealed no evidence for publication bias concerning diabetes and the risk of CC (including ICC and ECC).

CONCLUSIONS

The findings from this meta-analysis suggest that diabetes may increase the risk of cholangiocarcinoma. This relationship needs to be confirmed by further follow-up studies.

Type II diabetes mellitus is associated with a reduced risk of cholangiocarcinoma in patients with biliary tract diseases

It has not yet been reported whether Type II diabetes mellitus (DM) is associated with an increased cholangiocarcinoma (CC) risk in patients with biliary tract diseases. We identified 123,050 patients concomitantly diagnosed with biliary tract diseases and DM between 1998 and 2010. The control cohort consisted of 122,721 individuals with biliary tract diseases but not DM. Both cohorts were followed-up until the end of 2010 to estimate the risk of CC. We also compared the risk of CC between DM and non-DM cohorts without biliary tract diseases. Overall, the incidence of CC was 21% lower among the DM patients than among the control patients (1.11 vs. 1.41 per 1,000 person-years). DM cohorts exhibited significantly reduced risks for both intrahepatic and extrahepatic CC. A multivariable Cox proportional hazards regression model was used, and the adjusted hazard ratio (HR) of CC was 0.74 (95% confidence interval [CI], 0.66-0.82) for the DM cohort in comparison with the control cohort. The age-specific data indicated that compared with the control patients, the adjusted HRs for the DM patients were significantly lower among patients 50-64 (adjusted HR = 0.67; 95% CI = 0.55-0.82) and 65-74 years old (adjusted HR = 0.70; 95% CI, 0.59-0.84). Furthermore, DM was associated with a lower risk of CC among patients with biliary diseases, regardless of the presence of comorbidities and the status of cholecystectomy. In the patients without biliary tract diseases, DM is associated with significantly increased risk of CC (adjusted HR = 1.58; 95% CI, 1.37-1.82).

Risk of primary liver cancer associated with gallstones and cholecystectomy: a meta-analysis

Background

Recent epidemiological evidence points to an association between gallstones or cholecystectomy and the incidence risk of liver cancer, but the results are inconsistent. We present a meta-analysis of observational studies to explore this association.

Methods

We identified studies by a literature search of PubMed, EMBASE, Cochrane Central Register of Controlled Trials, and relevant conference proceedings up to March 2014. A random-effects model was used to generate pooled multivariable adjusted odds ratios (ORs) and 95% confidence intervals (CIs). Between-study heterogeneity was assessed using Cochran’s Q statistic and the I².

Results

Fifteen studies (five case-control and 10 cohort studies) were included in this analysis. There were 4,487,662 subjects in total, 17,945 diagnoses of liver cancer, 328,420 exposed to gallstones, and 884,507 exposed to cholecystectomy. Pooled results indicated a significant increased risk of liver cancer in patients with a history of gallstones (OR = 2.54; 95% CI, 1.71–3.79; n = 11 studies), as well as cholecystectomy (OR = 1.62; 95% CI, 1.29–2.02; n = 12 studies), but there was considerable heterogeneity among these studies. The effects estimates did not vary markedly when stratified by gender, study design, study region, and study quality. The multivariate meta-regression analysis suggested that study region and study quality appeared to explain the heterogeneity observed in the cholecystectomy analysis.

Conclusions

Our results suggest that individuals with a history of gallstones and cholecystectomy may have an increased risk of liver cancer.

Helicobacter pylori and extragastric diseases

While Helicobacter pylori infection was initially revealed to be associated only with some gastroduodenal diseases, further studies have shown its possible role in several extragastric diseases. For idiopathic thrombocytopenic purpura, sideropenic anemia, and vitamin B12 deficiency, the diagnosis of H. pylori infection is recommended, and there are many other conditions such as cardiovascular, neurological, dermatological, and respiratory diseases in which H. pylori may possibly play a role. Interestingly, a potential role has also been described for GI neoplastic diseases, including colorectal and pancreatic cancer. Different mechanisms of action have been proposed, ranging from the induction of a low grade inflammatory state to the occurrence of molecular mimicry mechanisms. This review summarizes the results of the most relevant studies published on this topic over the last year.

A clinical perspective on the role of chronic inflammation in gastrointestinal cancer

Chronic inflammation has been identified as an important risk factor for the development of malignancy, and knowledge about its molecular and cellular mechanisms is increasing. Several chronic inflammatory diseases of the gastrointestinal tract are important as risk factors for malignancy and have been studied in detail. In this review, we summarize important molecular mechanisms in chronic inflammation and highlight established and potential links between chronic inflammation and gastrointestinal cancer. In addition, we present the role of chronic inflammation in numerous tumors within the gastrointestinal tract as well as the relevant pathways or epidemiologic observations linking the pathogenesis of these tumors to inflammation.

Cholelithiasis and the risk of liver cancer: results from cohort studies of 134,546 Chinese men and women

BACKGROUND

Cholelithiasis and cholecystectomy have been proposed as risk factors for liver cancer, but findings have been inconsistent. We assessed this association using data from the Shanghai Women's and Men's Health Studies.

METHODS

History of cholelithiasis and cholecystectomy were reported at baseline and follow-up interviews, and liver cancer diagnoses were ascertained from the Shanghai Cancer Registry and Vital Statistics Unit. Adjusted hazard ratios (aHRs) and 95% CIs were calculated after adjustment for potential confounders.

RESULTS

A history of cholelithiasis and cholecystectomy was reported by 9.5% and 3.6% of participants at baseline, respectively. After a total of 859,882 person-years of follow-up for women and 391,093 for men, incident liver cancer was detected in 160 women and 252 men. A positive association was observed between a history of cholelithiasis or cholecystectomy and liver cancer in men (aHR 1.46; 95% CI 1.02 to 2.07) and women (aHR 1.55; 95% CI 1.06 to 2.26). Similar results were observed for cholelithiasis only, but cholecystectomy did not reach statistical significance. There was no strong evidence for detection bias of liver cancer due to cholelithiasis or cholecystectomy.

CONCLUSIONS

Our study suggests that cholelithiasis and possibly cholecystectomy may increase the risk of liver cancer.