Periodontal diseases and cancer

Abstract

Chronic periodontitis and aggressive periodontitis are inflammatory forms of periodontal disease (figure) caused by microorganisms from plaque biofilm that forms around the teeth. Chronic inflammation of the periodontium results in continuous release of cytokines, prostaglandins, bacterial toxins, and many other destructive enzymes from cells in the area. This chronic process leads to formation of periodontal pockets and progressive destruction of connective tissue and alveolar bone. 1 Pihlstrom B Michalowicz B Johnson N Periodontal diseases. Lancet. 2005; 366: 1809-1820 Summary Full Text Full Text PDF PubMed Scopus (2535) Google Scholar Chronic periodontitis and aggressive periodontitis are the most common causes of tooth loss in adults. Many studies have shown an association between periodontal diseases and systemic manifestations of cardiovascular disease, diabetes, and premature low-weight birth. 1 Pihlstrom B Michalowicz B Johnson N Periodontal diseases. Lancet. 2005; 366: 1809-1820 Summary Full Text Full Text PDF PubMed Scopus (2535) Google Scholar However, there is no evidence for a causal effect. A recent study assessed periodontitis and premature death in young adults in urban regions of Sweden. 2 Söder B Jin L Klinge B Söder P Periodontitis and premature death: a 16-year longitudinal study in a Swedish urban population. J Periodontal Res. 2007; 42: 361-366 Crossref PubMed Scopus (49) Google Scholar The findings showed that young individuals with periodontitis and missing molar teeth, compared with those with no periodontitis, had increased risk of premature death because of cancer, circulatory, and digestive diseases. In this issue of The Lancet Oncology, Michaud and colleagues 3 Michaud DS Liu Y Meyer M Giovannucci E Joshipura K Periodontal disease, tooth loss, and cancer risk in male health professionals: a prospective cohort study. Lancet Oncol. 2008; 9: 550-558 Summary Full Text Full Text PDF PubMed Scopus (261) Google Scholar present important data from a prospective study that shows an increase in cancer risk in a large population of well-characterised US male health professionals who self-reported having periodontal disease with alveolar bone loss. Their findings showed a significant association between periodontal disease and haematological, kidney, and pancreatic cancer. The cancer risk persisted in individuals who never smoked. In a previous study, 4 Michaud D Joshipura K Giovannucci E Fuchs C A prospective study of periodontal disease and pancreatic cancer in US male health professionals. J Natl Cancer Inst. 2007; 99: 171-175 Crossref PubMed Scopus (205) Google Scholar Michaud and co-workers suggested an association between periodontal disease and pancreatic cancer in the same population of health professionals. They concluded that plausible biological mechanisms, such as systemic inflammation or increased concentrations of carcinogenic compounds (or both) as a result of bacteria in the oral cavity of those with periodontal disease, could be involved in the development of cancer. Furthermore, a recent case–control study suggested that chronic periodontitis is associated with increased risk of developing tongue cancer. 5 Tezal M Sullivan M Reid M et al. Chronic periodontitis and the risk of tongue cancer. Arch Otolaryngol Head Neck Surg. 2007; 133: 450-454 Crossref PubMed Scopus (130) Google Scholar However, other researchers believe that the association between periodontal disease and cancer might be spurious. 6 Hujoel P Drangsholt M Spiekerman C Weiss N An exploration of the periodontitis-cancer association. Ann Epidemiol. 2003; 13: 312-316 Summary Full Text Full Text PDF PubMed Scopus (192) Google Scholar Therefore, future studies that assess in more detail potential mechanisms for the association between periodontal diseases and cancer are warranted. (A) Diagnosis should include clinical presentation, periodontal pocket probings, and radiographical assessment of bone levels. Note that the gingival tissues are red and swollen, and the level of the gingival margins is irregular. (B) Radiograph of top teeth shows only the tips of the roots inserted in alveolar bone (arrow). Periodontal disease, tooth loss, and cancer risk in male health professionals: a prospective cohort studyPeriodontal disease was associated with a small, but significant, increase in overall cancer risk, which persisted in never-smokers. The associations recorded for lung cancer are probably because of residual confounding by smoking. The increased risks noted for haematological, kidney, and pancreatic cancers need confirmation, but suggest that periodontal disease might be a marker of a susceptible immune system or might directly affect cancer risk. Full-Text PDF