The prospective clinical trial "PDA-MAPS - Pancreatic ductal adenocarcinoma - Microbiome as Predictor of Subtypes" aims to investigate the prognostic and predictive power of the orointestinal and tumoral microbiome in PDAC patients and associate findings with genetic, transcriptional and clinical data, in particular with treatment response. Patients with histologically confirmed PDA are enrolled at primary diagnosis and prior to oncological or surgical treatment. Rectal and buccal microbiome swabs as well as detailed clinical records are obtained from all patients. Following DNA extraction, both 16S rRNA and metagenomic sequencing will be performed using ONT sequencing platform. All data and clinical records are centrally stored, visualized and integrated via tranSMART and SEEK platforms.