Epstein-Barr Virus Infection and Risk of Breast Cancer: An Adaptive Meta-Analysis for Case-Control Studies

Context: The association between 'Epstein-Barr' virus (EBV) and breast cancer risk still remains controversial. A Systemic Review (SR) published in 2012 reported that there might be a statistically significant association between EBV and risk of breast cancer. However, errors were found in the appraisal process of the concerned SR..
The aim of this report was to conduct an adaptive meta-analysis with additional extraction of relevant papers published up until September 2015..
Data Sources: The lists of references, cited articles and related articles provided by PubMed were made using the articles selected in the previous SR..
Study Selection: Among these articles, only case-control studies using Polymerase Chain Reaction (PCR) techniques to detect EBV DNA in tissues were selected..
Data Extraction: The summary odds ratio (SOR) and the 95% confidence interval (CI) were calculated though meta- analysis..
A total of 20 case-control studies were selected, and the total numbers of subjects in the case and control groups were 1947 and 1010, respectively. The findings of this meta-analysis revealed that EBV infection might increase the risk of breast cancer (SOR = 3.84, 95% CI: 2.24-6.58; I-squared = 62.2%). Sub-group analyses by region, sample type, and control tissue showed that a statistical significance of the risk was still secured..
The findings of the meta-epidemiological study support that EBV infection may increase the risk of breast cancer. Nested case-control studies are required in the future..