Conversely, CD39+ resting Treg %resting Treg exhibited a negative correlation with biliary tract cancer risk, with a detection result of (OR=0.92, 95% CI=0.85–0.99, P=0.034), suggesting an association with an increased risk of biliary tract cancer, thus representing a risk factor for the disease. The gene discussed is ENTPD1; the disease is biliary tract neoplasm.