Association between infection of hepatitis B virus and onset risk of B-cell non-Hodgkin's lymphoma: a systematic review and a meta-analysis.

Whether an association between hepatitis B virus (HBV) infection and B-cell non-Hodgkin's lymphoma (B-NHL) risk exists is an open question. In order to provide quantification of the issue, we carried out a meta-analysis of the published data. We identified 4 case-control and 2 nested case-control studies, including a total of 5,396 B-NHL cases. We derived meta-analytic estimates using random-effects models, taking into account the correlation between estimates. The odds radio (OR) of HBV infection in B-NHL when compared with the control population was 2.98 [95 % confidence interval (CI) 2.30-3.86]. There was evidence of statistical heterogeneity among all included studies (I (2) = 65 %, P = 0.01), which disappeared in the subgroup nested case-control studies (I (2) = 0 %, P = 0.49). OR was 2.59 (95 % CI 2.03-3.30) in the random effect model, suggesting a higher prevalence of HBV carrier state in B-NHL than controls. This meta-analysis provides quantitative evidence of a favorable role of HBV infection on B-NHL risk, which needs to be confirmed by experimental and epidemiological studies.