(Reuters Health) – Gum infections can increase a person's risk of having sores in the digestive tract that can lead to stomach cancer, a small study suggests.
The researchers focused on what is known as periodontal disease, serious infections in the mouth caused by bacteria in the dental plaque. Daily brushing and flossing can prevent gingivitis, the mildest form of periodontal disease, but untreated cases can cause permanent damage to the gums and bone.
The new study involved 35 people with so-called precancerous lesions: abnormal cells or sores in the digestive tract where cancer is more likely to occur compared to normal tissue. The researchers also studied a control group of 70 similar people who did not have these lesions.
Overall, 32 percent of people with precancerous gastric lesions had the type of bleeding during dental examinations that is a hallmark of periodontal disease, compared to 22 percent of people without precancerous lesions, found the study.
People with precancerous gastric lesions were also more likely to have high levels of various types of bacteria in the mouth that can contribute to periodontal disease.
"These bacteria are commonly found in periodontal pockets and are invasive because they can produce a variety of molecules that can damage host tissue and host responses to bacterial colonization, thus contributing to the development of cancer," he said. principal author of the study. Yihong Li, researcher at the School of Dentistry of the New York University in New York City.
"Periodontal pockets are not easy to access with a common toothbrush and could serve as a reservoir for bacterial colonization and potentially a source of chronic inflammation and carcinogenic bacteria (growth)," Li said by email.
Many cases of gastric cancer are related to smoking and eating high-salt foods or preservatives, the researchers note in their report in the Journal of Periodontology. Poor oral health has also been linked to these tumors.
The study was not a controlled experiment designed to test whether oral health problems could contribute to stomach cancer, the researchers observed. Precancerous lesions also do not always turn into cancer.
Still, the findings add to the evidence that periodontal disease may play a role in the development of stomach cancer, said Jean Wactawski-Wende, a researcher at the University of Buffalo who was not involved in the study.
Inflammation can play a role, Wactawski-Wende said by email. Periodontal disease can cause inflammation in the mouth and also contribute to inflammation throughout the body. Some bacteria in the mouth can also travel from the mouth to the gastrointestinal tract.
"This study is small and can not prove causality, but there is growing evidence that periodontal disease may be associated with certain types of cancer, including gastrointestinal cancer," Wactawski-Wende added. "Maintaining good oral hygiene by brushing and flossing and visiting the dentist regularly can be prudent."
SOURCE: bit.ly/2iBGny7 Journal of Periodontology, online November 27, 2017.