IADR Abstract Archives
Oral Microbiota in Early Cystic Precursors to Invasive Pancreatic Cancer
Objectives: Pancreatic cancer (PC) increasingly impacts public health, being the fourth-leading cause of cancer-related death in Western countries with a low overall survival rate and rapid deterioration in quality of life. Intraductal papillary mucinous neoplasms (IPMNs) rank as the most common pancreatic cystic tumours and can progress to invasive PC. Previously, risk for PC development has been associated with poor oral health and salivary microbiome alterations. We aimed to investigate the pancreatic microbiome of IPMN and its relation to disease severity.
Methods: Patients with suspected pancreatic cystic neoplasm (PCN) undergoing pancreatic resection were included in this study. Peri-operative intracystic fluid (CF) was collected from the tumours, and analysed by 16S DNA qPCR, PacBio whole-16S gene sequencing, interleukin 1-beta (IL-1β) and bacterial LPS quantification. Viable bacteria were detected by the BACT/ALERT system and characterized further. Data were correlated to pancreas diagnoses verified by histopathology examination and clinical laboratory tests.
Results: Compared to non-IPMNs, the 16S DNA and IL-1β in CF were found significantly higher among IPMNs. Interestingly, the 16S DNA and IL-1β levels were higher in IPMNs showing high-grade dysplasia (HGD) compared to IPMNs with low-grade dysplasia and other benign tumours. Although the intracystic microbial composition showed a high interpersonal variation, bacterial network analysis revealed a significant co-occurrence of oral bacterial taxa. IPMN with HGD in particular, was enriched for Fusobacterium nucleatum and Granulicatella adiacens, and the presence of viable oral bacteria were confirmed by the BACT/ALERT culture system and bacterial identification.
Conclusions: Combining culture-dependent and culture-independent methods to detect oral bacteria in the pancreas can improve detection of cancerous pancreatic IPMNs. Our result addresses an important clinical need in the pancreatic tumour management. The role of oral bacteria in pancreatic CF and PCN progression remains to be elucidated.
Methods: Patients with suspected pancreatic cystic neoplasm (PCN) undergoing pancreatic resection were included in this study. Peri-operative intracystic fluid (CF) was collected from the tumours, and analysed by 16S DNA qPCR, PacBio whole-16S gene sequencing, interleukin 1-beta (IL-1β) and bacterial LPS quantification. Viable bacteria were detected by the BACT/ALERT system and characterized further. Data were correlated to pancreas diagnoses verified by histopathology examination and clinical laboratory tests.
Results: Compared to non-IPMNs, the 16S DNA and IL-1β in CF were found significantly higher among IPMNs. Interestingly, the 16S DNA and IL-1β levels were higher in IPMNs showing high-grade dysplasia (HGD) compared to IPMNs with low-grade dysplasia and other benign tumours. Although the intracystic microbial composition showed a high interpersonal variation, bacterial network analysis revealed a significant co-occurrence of oral bacterial taxa. IPMN with HGD in particular, was enriched for Fusobacterium nucleatum and Granulicatella adiacens, and the presence of viable oral bacteria were confirmed by the BACT/ALERT culture system and bacterial identification.
Conclusions: Combining culture-dependent and culture-independent methods to detect oral bacteria in the pancreas can improve detection of cancerous pancreatic IPMNs. Our result addresses an important clinical need in the pancreatic tumour management. The role of oral bacteria in pancreatic CF and PCN progression remains to be elucidated.