Association between viral infection other than human papillomavirus and risk of esophageal carcinoma: a comprehensive meta-analysis of epidemiological studies.

Infection with viruses such as human papillomavirus (HPV) is known to induce carcinomas, including esophageal carcinoma (EC). However, the possible role of viruses other than HPV in EC carcinogenesis is unclear in many studies. Here, we aimed to explore the association between infection with viruses other than HPV and EC risk by integrating existing studies of epidemiology in a meta-analysis. The PubMed, Web of Science, Cochrane Library and China National Knowledge Infrastructure databases were searched. The Newcastle-Ottawa scale was used to assess the quality of the included studies. Odds ratios (ORs) or relative risks (RRs) (with 95% confidence intervals [CIs]) were pooled to estimate the association between virus infection and risk of EC. We included 31 eligible studies involving nine different viruses. Overall, an increased risk of EC was associated with hepatitis B virus (HBV) infection (OR = 1.19, 95%CI 1.01-1.36) and hepatitis C virus (HCV) infection (OR = 1.77, 95%CI 1.17-2.36), but not human immunodeficiency virus (HIV) infection, according to the current evidence. The evidence for an association with Epstein-Barr virus (EBV), herpes simplex virus 1 (HSV-1), JC virus (JCV), cytomegalovirus (CMV), human T-lymphotropic virus 1 (HTLV-1) or Merkel cell polyomavirus (MCPyV) infection was insufficient. We confirmed the relationship between HBV and HCV infection and the risk of EC, but we found no association of EC risk with HIV and EBV infection. The roles of HSV-1, JCV, CMV, HTLV-1, and MCPyV were not clear because of the limited number of studies.