Pancreatic cancer, specifically pancreatic ductal adenocarcinoma (PDAC), accounts for more than 90% of pancreatic tumors and is the most aggressive form of the disease due to late diagnosis and resistance to treatment[1]. Recent research shows that the microbial ecosystems in the body play an active role in the development of pancreatic cancer through four anatomical regions – the gastrointestinal tract, the oral cavity, the genitourinary system and the pancreas itself[1]. Specific bacteria such as Fusobacterium nucleatum, Porphyromonas gingivalis and Malassezia spp. they promote tumorigenesis by suppressing the immune system, altering cell metabolism and causing chronic inflammation[1]. These microbial organisms also reduce the effectiveness of chemotherapy, including the drug gemcitabine, which they inactivate with enzymes[1]. Conversely, some beneficial bacteria and probiotic species can strengthen the immune system and increase the effectiveness of treatment[1]. Research suggests that microbial markers could be used for early detection of pancreatic cancer and that interventions targeting the microbiome – such as faecal microbiota transplantation, probiotics and selective antibiotics – could represent new treatment options[1].