Human papillomavirus (HPV) in breast tumors: prevalence in a group of Mexican patients.

Background: Breast cancer is one of the main health problems in developed countries, occupying first place in mortality in women. It is well-known that there are risk factors associated with breast cancer development. Nonetheless, in 50-80% of cases known risk factors have not been identified, this has generated the attempt to identify new factors related with this neoplasia as viral infections.