Oral microbiome and pancreatic cancer.

BACKGROUND

Microbiota profiles differ between patients with pancreatic cancer and healthy people, and understanding these differences may help in early detection of pancreatic cancer. Saliva sampling is an easy and cost-effective way to determine microbiota profiles compared to fecal and tissue sample collection.

AIM

To investigate the saliva microbiome distribution in patients with pancreatic adenocarcinoma (PDAC) and the role of oral microbiota profiles in detection and risk prediction of pancreatic cancer.

METHODS

We conducted a prospective study of patients with pancreatic cancer ( = 41) and healthy individuals ( = 69). Bacterial taxa were identified by 16S ribosomal ribonucleic acid gene sequencing, and a linear discriminant analysis effect size algorithm was used to identify differences in taxa. Operational taxonomic unit values of all selected taxa were converted into a normalized Z-score, and logistic regressions were used to calculate risk prediction of pancreatic cancer.

RESULTS

Compared with the healthy control group, carriage of and (z-score) was associated with a higher risk of PDAC [odds ratio (OR) = 5.344, 95% confidence interval (CI): 1.282-22.282, = 0.021 and OR = 6.886, 95%CI: 1.423-33.337, = 0.016, respectively]. and (z-score) were considered a protective microbe that decreased the risk of PDAC (OR = 0.187, 95%CI: 0.055-0.631, = 0.007 and OR = 0.309, 95%CI: 0.100-0.952, = 0.041, respectively). Among the patients with PDAC, patients reporting bloating have a higher abundance of ( = 0.039), ( = 0.024), and ( = 0.041); while patients reporting jaundice had a higher amount of ( = 0.008); patients reporting dark brown urine had a higher amount of ( = 0.035). Patients reporting diarrhea had a lower amount of and ( = 0.024 and = 0.034), and patients reporting vomiting had decreased ( = 0.036).

CONCLUSION

Saliva microbiome was able to distinguish patients with pancreatic cancer and healthy individuals. may be specific for patients living in Sichuan Province, southwest China. Symptomatic patients had different bacteria profiles than asymptomatic patients. Combined symptom and microbiome evaluation may help in the early detection of pancreatic cancer.