Helicobacter pylori and Biliary Tract Cancers: A Meta-Analysis

Background. Helicobacter pylori is detected in various extragastric diseases, including biliary tract cancers. Besides, gallbladder cancers, extracholangiocarcinomas, and intracholangiocarcinomas are highly lethal cancers with limited survival due to their late diagnosis. Epidemiological data on Helicobacter pylori infection and biliary tract cancer have been contradictory. Aim. The aim of this study is to explore and evaluate the association between the Helicobacter pylori infection and biliary tract cancer. Materials and Methods. Systematic literature research was carried out to identify all eligible articles. All relevant publications from 2000 to 2019 were retrieved using comprehensive combinations of keywords. We used a random effects model to calculate pooled prevalence estimates, and 95% confidence intervals (CIs) for odds ratio were also calculated. Quantitative assessment of heterogeneity was explored by the chi-square test and was measured using I2. Results. Thirteen case-control studies published between 2001 and 2018 were included. The overall meta-analysis favoured a significant association between Helicobacter pylori infection and biliary tract cancer (OR, 2.57; 95% CI, 1.35–4.91; I2？=？58%). Geographic distribution-based subgroup analysis showed a higher prevalence of H. pylori in Asian and North American countries. Evidence supporting the higher presence of Helicobacter pylori in a cancer group was found by PCR. In another subgroup, the ORs were 4.18 (2.03, 8.58) in cholangiocarcinoma, 1.36 (0.34, 5.44) in gallbladder cancer, and 5.93 (1.89, 18.63) in other biliary tract cancers. Conclusion. This meta-analysis suggests that infection of the biliary tract with Helicobacter pylori is related to an increased risk of biliary tract cancers