Is breast cancer caused by late exposure to a common virus?

Med Hypotheses. 1997 Jun;48(6):491-7. doi: 10.1016/s0306-9877(97)90118-3.


Although there are recognized risk factors for breast cancer, its cause is still unknown. It is hypothesized here that breast cancer results from late exposure to a common virus. This hypothesis is investigated by relating the epidemiology of breast cancer to the seroepidemiology of cytomegalovirus, as a surrogate for a breast cancer virus. The hypothesis is consistent with the geographical distribution of breast cancer; a correlation between breast cancer incidence and the percentage of adults who are cytomegalovirus seropositive in various countries was found (Pearson correlation coefficient -0.79). The hypothesis is also consistent with other risk factors for breast cancer, such as age at onset, family history, hormonal factors and migration.

MeSH terms

  • Adult
  • Age Factors
  • Antibodies, Viral / blood
  • Breast Neoplasms / epidemiology
  • Breast Neoplasms / etiology*
  • Breast Neoplasms / virology*
  • Cytomegalovirus / immunology
  • Cytomegalovirus / pathogenicity*
  • Cytomegalovirus Infections / complications
  • Cytomegalovirus Infections / epidemiology
  • Cytomegalovirus Infections / immunology
  • Female
  • Genes, p53
  • Hormones / metabolism
  • Humans
  • Models, Biological
  • Mutation
  • Risk Factors
  • Seroepidemiologic Studies
  • Socioeconomic Factors


  • Antibodies, Viral
  • Hormones