The challenge for medical oncology is to develop plasma biomarkers that can detect the influence of the stroma on diagnosis, prognosis and response to chemotherapy. Today, there is no validated blood test to help diagnose pancreatic cancer (PDAC). The search for blood biomarkers of the tumor stroma and immunological markers is therefore a major challenge in orienting the diagnosis towards PDAC and optimizing the therapeutic management of pancreatic cancers. The aim of the study is to identify biomarkers associated with the presence of malignant pancreatic lesions (patients from the Pancreas-CGE cohort, a cohort already set up by our team) compared with benign lesions (patients followed up for benign pancreatic lesions). Candidate biomarkers from our preliminary work will be considered initially. Other biomarkers may be explored secondarily. The ultimate goal is to develop a clinico-biological signature that is as efficient as possible in predicting the presence of malignant pancreatic lesions compared with benign ones.