EBV is a herpes virus most commonly known for causing mononucleosis, a mild illness that typically affects teenagers and young adults. Scientists are finding increasing evidence that infections play an important role in cancer. Human papillomavirus, which causes genital warts, has long been known to increase a woman's risk of cervical cancer. And earlier this month, English researchers found clues to support the hypothesis that exposure to infection heightens the risk of childhood leukemia.
Breast cancer is one of the most common cancers among women in industrialized countries.
Some scientists believe that EBV may one day make this list. In the latest study, French researchers from the Institute Gustav Roussy analyzed malignant tissue from 100 breast cancer patients. EBV was found in approximately half of these specimens. The virus was detected more often in the most aggressive tumors. And, in 4 out of 5 cases where the cancer had spread to patient's lymph nodes, EBV was present.