Reactivity with A monoclonal antibody to Epstein-Barr virus (EBV) nuclear antigen 1 defines a subset of aggressive breast cancers in the absence of the EBV genome.

Previous studies have suggested that common breast cancers are associated with EBV. We used a highly sensitive quantitative real-time PCR method to screen whole tumor sections of breast cancers for the presence of the EBV genome. EBV DNA was detected in 19 of 92 (21%) tumors, but viral load was very low in positive samples (mean = 1.