A new study suggests a link between periodontal disease and breast cancer in post-menopausal women. Other pathogens have been linked to oral cancer. The risk for these cancers increases for those who smoke.
Microorganisms found in the mouth have been found in breast tumors. There are some associations among certain bacteria and cancers.
Additionally, infections have been linked to increased risks of malignant changes. It has also been speculated that some bacteria can cause chronic infections or produce toxins that disturb the cell cycle and alter cell growth.
Some bacterial infections stimulate immune responses that cause tissue damage. This is the case with periodontal disease. C-reactive protein is produced. Periodontal ligament damage and bone loss occur, resulting in eventual tooth loss. These same types of infection can contribute to carcinogenic alterations.
In one study, more than a quarter of post-menopausal women were found to have periodontal disease at the beginning of the self-reported study. None of the women had a history of breast cancer at the onset of the study.
After seven years, at the conclusion of the study, women with periodontal disease were at 14 percent higher risk of breast cancer. It can be concluded that the systemic inflammation from the periodontal disease could affect the breast tissue or the oral bacteria entering the circulatory system could affect the tissue.
Researchers have also found approximately 36 percent higher risk of breast cancer in patients with periodontal disease among those who smoke. Causal factors include, once again, bacteria and inflammatory response.