EBV as a potential risk factor for hepatobiliary system cancer: A meta-analysis with 918 cases

Hepatobiliary system cancer, which includes hepatocellular carcinoma (HCC), cholangiocarcinoma, and gallbladder carcinoma, has an increase of incidence and mortality due to various risk factors. Epstein-Barr virus (EBV) is associated with various types of lymphomas and carcinomas, which is also acknowledged as the first-discovered human tumor virus. Despite this, there is no systematic analysis about the relationship between the infection of EBV and hepatobiliary system cancer. The aim of this meta-analysis is to explore the significance of EBV infection in the development of hepatobiliary system cancer by evaluating the EBV infection ratio.

A systematic search of PubMed, Embase, Cochrane Library, as well as China National Knowledge Infrastructure (CNKI), Chongqing VIP, Wan Fang, and China Biology Medicine databases was conducted. The EBV infection ratio and 95% confidence intervals (CIs) in hepatobiliary system cancer was evaluated. The I² statistic was used to represent heterogeneity. Through meta-regression, stratified analyses were applied to find out heterogeneity's sources. Odds ratios (ORs), 95% CIs of EBV infection in case-control studies were calculated.

Altogether, 15 studies were included containing a total of 918 cases and 157 controls. The whole infection ratio of EBV was 23% (95% CI: 13%, 33%, I² = 95.7%, P < 0.001) among all the patients. Comparable EVB infection ratios were observed in hepatobiliary system cancer as divided into different subtypes. The five case-control studies were epitomized to a pooled OR of 9.35 (95%CI: 2.95, 29.61, I² = 20.1%, P < 0.286).

EBV may be a potentially risk factor in the process of hepatobiliary system cancer. The prospective molecular mechanism remains to be explored.