Pancreatic Cancer Patients With More Natural Teeth Lived Nearly Two Years Longer, Study Finds

Patients who have more natural teeth at the time of surgery for pancreatic cancer may live significantly longer than those who have lost many of their teeth, according to new research from Hiroshima University. The findings highlight oral health as a potential marker of overall resilience in a cancer known for particularly poor outcomes.

Pancreatic ductal adenocarcinoma, or PDAC, is one of the deadliest cancers worldwide, with many patients dying within a few years even after aggressive surgery. Previous research has linked poor oral health with worse outcomes in colorectal and esophageal cancers, as well as with post-surgical complications in people undergoing treatment for pancreatic cancer.

Study links teeth and survival

The Hiroshima University team analyzed 339 consecutive patients who underwent radical pancreatectomy between 2014 and 2022. All participants were treated at Hiroshima University Hospital and received a standardized preoperative dental examination before surgery.

Researchers counted the number of natural teeth each patient still had and assessed occlusion, meaning how well the upper and lower premolars and molars met when biting. These two measures were used as indicators of oral health and chewing function at the time of surgery.

The patients were then followed to assess overall survival after pancreatectomy. The researchers adjusted their analysis for major prognostic factors, including tumor stage, lymph node involvement, surgical margins, chemotherapy use and nutritional status.

Nearly two-year survival gap

The results revealed a substantial difference in survival according to the number of remaining natural teeth. Patients with 21 or more natural teeth had a median overall survival of 60.7 months, compared with 39.1 months among those with 20 or fewer teeth — a difference of almost two years.

The association remained statistically significant after the researchers accounted for established clinical and pathological risk factors. This suggests that tooth count may capture an additional layer of risk that conventional measures used in cancer prognosis do not fully explain.

In contrast, chewing function alone, measured through posterior tooth occlusion, did not independently predict survival. This suggests that the association cannot simply be explained by the mechanical ability to chew.

Oral health as a systemic marker

Lead author Kenichiro Uemura, an associate professor at Hiroshima University’s Graduate School of Biomedical and Health Sciences, said tooth loss may reflect decades of systemic stress. Chronic inflammation, frailty, nutritional status and lifestyle factors could all contribute to this relationship.

Previous studies have linked periodontal pathogens such as Porphyromonas gingivalis with pancreatic carcinogenesis and tumor progression. The new findings support the idea that long-term oral health may reflect the body’s broader vulnerability to aggressive disease.

The researchers propose that the number of remaining teeth could serve as a simple and inexpensive risk indicator before surgery. When considered alongside imaging, pathology and genetic markers, an oral health assessment might help refine evaluations of which patients are most likely to benefit from major operations.

Implications and next research steps

The authors caution that the findings come from a single-center study involving Japanese patients and therefore need to be validated in larger and more diverse populations. Multicenter and international studies will be necessary to determine whether the association between tooth count and survival is also observed across different ethnic groups and healthcare settings.

Future research will aim to clarify the biological pathways connecting oral bacteria, chronic inflammation and pancreatic cancer behavior. A better understanding of these mechanisms could eventually lead to new prevention and supportive-care strategies that incorporate dental interventions.

Uemura and his colleagues envision a broader approach to pancreatic cancer care in which prognosis reflects not only the biology of the tumor but also a patient’s long-term systemic condition and oral environment. They suggest that routine dental assessment could one day become part of personalized risk stratification and perioperative planning.

The study, published in the Journal of Hepato-Biliary-Pancreatic Sciences, was co-authored by researchers from Hiroshima University, Hiroshima University Hospital and Hiroshima Memorial Hospital. Although the findings do not establish causality, they strengthen the case for considering oral health as a potential window into cancer outcomes.