Hepatitis B infection increases the risk of non-Hodgkin lymphoma: a meta-analysis of observational studies.

Hepatitis B virus (HBV) infection is a major public health problem and the association between HBV infection and non-Hodgkin lymphoma (NHL) is unclear. The primary aim of our study was to evaluate the association between HBV infection assessed by a positive hepatitis B surface antigen (HBsAg) and the incidence of NHL and subtypes using a meta-analysis of epidemiological studies. The random effects model was used to calculate the outcome. Our search yielded 17 case-control and 5 cohort studies, including over 40,000 NHL cases. HBV infected individuals had an OR of 2.24 (95% CI 1.80-2.78; p ≤ 0.001) of developing NHL. In high HBV prevalent countries, there were increased odds of diffuse large B-cell lymphoma and a trend toward increased odds of developing follicular and T-cell lymphoma. Future research is needed to better understand the biological mechanisms responsible for lymphomagenesis in patients with HBV infection.