PMC

chematic of the strategy used for the discovery (including verification) and validation of salivary bacterial biomarkers. PC, pancreatic cancer; HC, healthy control; CP, chronic pancreatitis.

16S rRNA gene-based phylogenetic tree of 56 varied clusters/genera between patients with pancreatic cancer and healthy controls. Thirty-one clusters/species increased in the saliva of pancreatic cancer patients were marked with triangles. The phylogenetic tree was inferred by a minimum evolution analysis of 16S rRNA sequences.

nteractive dot diagram analysis and receiver operating characteristic (ROC) curve analysis for the predictive power of combined salivary bacterial biomarkers. The validated biomarkers were evaluated by logistic regression within three levels of clinical discrimination categories: pancreatic cancer versus healthy control (A), pancreatic cancer versus chronic pancreatitis (B) and pancreatic cancer versus non-cancer (healthy control + chronic pancreatitis) (C). The sensitivity and specificity for each model were obtained by identifying the cut-off point in the predicted probabilities from the logistic regression that maximised the sum of the sensitivity plus specificity. In general, these cut-off points correspond well with the proportion of patients with cancer evaluated in each model.