- Pathogens can enter bloodstream through saliva or diseased gum tissue
New research has confirmed that periodontal disease is tied to an elevated risk of several types of cancer, such as oesophagal cancer, breast cancer, and gallbladder cancer, especially in mature women.
The researchers found that women who had reported a diagnosis of periodontal disease had a 14 per cent higher risk of developing any type of cancer.
Esophageal cancer was the type most frequently associated with gum disease, as women with periodontitis were more than three times likelier to develop it compared with women without oral health problems.
“The oesophagus is in close proximity to the oral cavity, and so periodontal pathogens may more easily gain access to and infect the oesophagal mucosa and promote cancer risk at that site,” explains Dr Wactawski-Wende.
The association between periodontitis and gallbladder cancer was a new discovery, according to the researchers.
Lead author Dr Ngozi Nwizu, from the University Of Texas School Of Dentistry in Houston, TX, emphasises the importance of this finding.
“Chronic inflammation has also been implicated in gallbladder cancer, but there has been no data on the association between periodontal disease and gallbladder risk. Ours is the first study to report on such an association.”
Dr Wactawski-Wende and her colleagues also found a strong link between gum disease and breast cancer, lung cancer, and gallbladder cancer in the case of women who smoked. Especially significant, according to Dr Nwizu, were the verdicts on gallbladder cancer and cancer of the oesophagus.
Esophageal cancer still has no known causes, so the researchers hope that this will be the first step in gaining a better understanding of its formation.
“Esophageal cancer ranks among the most deadly cancers and its aetiology is not well known, but chronic inflammation has been implicated,” says Dr Nwizu. The next step, she suggests, will be to determine whether bacteria linked to gum disease also play a role in inflammation related to oesophagal cancer:
“Certain periodontal bacteria have been shown to promote inflammation […], and these bacteria have been isolated from many organ systems and some cancers including oesophagal cancers. It is important to establish if periodontal disease is an important risk of oesophagal cancer, so that appropriate preventive measures can be promoted.”
What exactly causes the link between periodontitis and various types of cancer is yet to be understood. One explanation offered by the researchers is that bacteria and other pathogens from the mouth might make their way into the bloodstream through saliva or diseased gum tissue.
In this way, pathogens could reach various parts of the body and be involved in the process of cancer formation. However, more research needs to be carried out in this direction to establish the actual mechanism at play.
The researchers acknowledge that their study faced some limitations – mainly the fact that the data used for the analysis were self-reported by the participants, so they may not have been entirely accurate.
Nevertheless, Dr Wactawski-Wende and her colleagues place their confidence in the extensive size of the population sample, emphasising the comprehensiveness of their study and the impact of their novel findings.
“Our study was sufficiently large and detailed enough to examine not just overall risk of cancer among older women with periodontal disease, but also to provide useful information on a number of cancer-specific sites,” conclude the researchers.