Significant gaps exist in understanding the gastrointestinal microbiota in patients with pancreatic cancer (PCA) versus benign or low-grade malignant pancreatic tumors (NPCA). This study aimed to analyze these microbiota characteristics and explore their potential use in distinguishing malignant pancreatic lesions.

In the past decade, microbiome research has rapidly progressed, revealing the critical roles of fecal and oral microbiota in maintaining internal homeostasis. Studies employing 16S rRNA and metagenomics have highlighted dysbiosis of the fecal and oral microbiota as closely linked to PCA development and progression. However, significant gaps exist in understanding the fecal and oral microbiota in patients with pancreatic cancer (PCA) versus benign or low-grade malignant pancreatic tumors (NPCA). This study aimed to analyze fecal and oral microbiota characteristics, and to establish classifiers to discriminate PCA from NPCA, providing a reference for early clinical identification of malignant tumors.

Inclusion Criteria:

• Patients with a pancreatic tumor detected via imaging with no prior treatment before sample collection
• Patients volunteer to provide oral and fecal samples

Exclusion Criteria:

• Current or previous diagnoses of (a) other malignancies, (b) infectious diseases, (c) oral or gastrointestinal disorders (d) psychiatric or neurodegenerative disorders
• Specific medical procedures or interventions within defined periods, including (a) antibiotic, hormone therapy, or immunosuppressant within the past three months, (b) gastrointestinal reconstructive surgery within the past three months, (c) frequent use of cathartics, antidiarrheals, or therapeutic doses of probiotics within the past month, (d) oral or gastrointestinal examinations within the past three days

Patients with a pancreatic tumor detected via imaging