Oncogenic viruses in nipple aspirate fluid: biomarkers for breast cancer risk assessment?

It would be a considerable advantage to be able to identify women at high risk for developing breast cancer to justify closer follow-up and use of multiple methods to ensure early detection. At present, the only high risk individuals identifiable with a biomarker are those ≈5% with a strong familial history of breast cancer. For the remaining 95% there is a lack of such biomarkers. Three independent epidemiologic studies found that women with mammary epithelial cells (MEC) in their nipple aspirate fluids (NAF) were more likely to subsequently develop breast cancer than women without cells. A possible explanation for this is that early stages of breast carcinogenesis and tumor progression most likely involve MEC hyperplasia triggered by a carcinogenic agent. Viruses cause several major human cancers (e.g. primary liver cancer and cervical cancer). Recent studies found bovine leukemia virus (BLV), Epstein-Barr virus (EBV), and human papilloma virus (HPV) more frequently in breast tissues of women with breast cancer vs. those with no breast cancer history.