As we understand the body better, we see more and more connections between things we used to think were separate. In particular, we notice how some illnesses can cause a cascade effect, resulting in numerous others.

Gum disease seems to be one of these illnesses, since it has been connected to heart disease, pregnancy complications, and now cancer. Several recent studies have shown that gum disease may increase your risk for some type of oral cancer, which makes detection and treatment an even higher priority than before. Further research also links gum disease and other types of cancer. However, to understand the link between gum disease and cancer, we have to understand how gum disease could increase cancer risk.

senior woman smiling sitting on couchCorrelation between Oral Cancer and Gum Disease

A 2013 study published in the Journal of Head and Neck Medicine showed a correlation between oral cancer and gum disease. Researchers looked at 178 patients who had been diagnosed with oral squamous cell carcinoma (OSCC), which accounts for about 90% of all oral cancers. The cancer patients were compared to 123 healthy controls matched for age. They found that bone loss around the teeth–a symptom of gum disease–was significantly correlated with OSCC risk. People with cancer as a whole had lost more bone mass–an average of about 4mm–compared to those without cancer, who had lost around 3 mm.

In a similar, earlier study, tongue cancer has also been linked to periodontal disease. This study, published in the  Journal of the American Medical Association (JAMA)’s Otolaryngology–Head & Neck Surgery, matched 51 men who had tongue cancer with 53 men who had not been diagnosed. The results showed that people with chronic gum disease were more than five times more likely to develop tongue cancer.

Another study posited a potential tie between the two conditions: perhaps human papillomavirus (HPV) found a conducive environment when a person had gum disease. Because of a massive publicity campaign surrounding the vaccine, most people know the HPV virus is linked to cervical cancer but may not realize it’s associated with many oral cancers as well. This study suggested that each millimeter of bone loss was linked to a 4-fold increase in the risk that you would develop HPV-related tongue cancer.

Other Cancers Linked to Gum Disease

However, it is not only oral cancer linked to gum disease. Several studies demonstrate that there might be a statistical link between gum disease and many types of cancer.

One study with a large population (more than 7000 people) from 2018 showed a 24% higher cancer risk in people with severe gum disease than those with no gum disease or mild gum disease. The strongest links with gum disease were lung cancer and colorectal cancer.

An even more extensive study (more than 48,000 men only) from 2008 showed a 14% higher overall cancer risk, with a statistically higher risk of lung cancer, kidney, pancreatic, and blood cancers.

A still larger study (nearly 66,000 women only) from 2017 reported a similar increase in overall cancer risk (12%). For women, breast cancer, lung cancer, esophageal cancer, gallbladder cancer, and melanoma all saw increased risk with gum disease.

These strong statistical links are convincing, but to show a potential for causation, we need to show that there’s a mechanism by which gum disease might contribute to cancer risk.

How Gum Disease Can Increase Cancer Risk

Research also shows how gum disease bacteria directly contribute to your cancer risk. Researchers found oral bacteria growing in and among tumors for a long time. Now research shows that this is not accidental: the oral bacteria help tumors grow so that they can prosper.

One gum disease bacterium that impacts cancer risk is Fusobacterium nucleatum. F. nucleatum encourages the development of intestinal tumors. It encourages inflammation that stimulates the growth of tumors.  It recruits certain types of cells that accelerate tumor growth. F. nucleatum gives off proteins that bind to human immune cells, preventing these cells from attacking small tumors. This allows more tumors to grow.

The result is that people with a high level of F. nucleatum may experience more tumors that grow faster than people without this type of oral bacterium.

While most of this work relates to intestinal tumors, similar mechanisms are plausible for tumors in other parts of the body. Inhaled oral bacteria contribute to pneumonia and may also contribute to the development of lung cancer. Oral bacteria can travel through your blood to all parts of the body. Oral bacteria appear in arterial plaque, for example, showing that they not only survive but thrive in the bloodstream.

Prevention and Screening

At Rice Dentistry, we are fully committed to helping you maintain a healthy mouth. Part of that is our advanced screening program for oral cancer, which allows us to detect oral cancer at an earlier stage, which increases your risk of survival and positive outcomes with only noninvasive treatments.

We also help you control gum disease with regular checkups, professional cleaning, and gum disease treatment when necessary.

To learn more about your potential benefit from oral cancer screening, please contact Rice Dentistry in Irvine today for more information.