Risk of cancer in patients with recurrent aphthous stomatitis in Korea: A nationwide population-based study.

The relationship between recurrent aphthous stomatitis (RAS), a common mucosal lesion, and cancer has not been demonstrated. This study investigated the risk for developing cancer in patients with RAS, based on data from Korea's National Health Insurance Sharing Service (NHISS). Nationwide population-based cohort data from 2005 to 2009 provided by the NHISS was used. The group diagnosed with RAS for 5 years and an undiagnosed control group were constructed through 1:1 propensity score matching (PSM). The experimental design compared the incidence rate of a cancer diagnosis from 2010 to 2015 between these 2 groups. After identifying 13,808 people that met our inclusion criterion from a 1 million cohort group, 13,808 controls were included in the study through PSM. Among all cancers, pancreatic cancer had an adjusted hazard ratio of 1.26 (95% confidence interval: 1.01-1.57, P < .041). For the rest of the cancers, there was no significant incidence rate. RAS was associated with an increased risk of pancreatic cancer in the analysis using large population-based cohort data. Further long-term follow-up studies are needed.