Prevention of Postoperative Pancreatic Fistula Following Pancreaticoduodenectomy by Preoperative Radiotherapy : a Phase 2 Trial

Inclusion Criteria: * Aged ≥ 45 years old * Candidate for pancreaticoduodenectomy by laparotomy * Body mass index (BMI) ≥ 25kg/m2 * Diameter of main pancreatic duct (MPD) \< 3 mm on preoperative CT scan or MRI at the isthmus of the pancreas (future pancreatic section area) * Affiliation to a social security system (AME excepted) * Signed informed consent Exclusion Criteria: * Surgery indication : Chronic pancreatitis * Surgery indication : Pancreatic ductal adenocarcinoma * History of syndromic or hereditary pancreatic tumor * Contraindication to pancreaticoduodenectomy * Planned multivisceral resection involving organs or parts of organs not normally involved in pancreatico-duodenectomy * Planned external drainage of the main pancreatic duct at the end of the surgery * Neoadjuvant treatment planned or performed by chemotherapy or radiotherapy * History of chronic hepatitis (F3) or cirrhosis (F4) * Contraindication to radiotherapy * Previous history of abdominal radiotherapy * Extended pancreatic resection on the left beyond the radiotherapy area (left of the pancreatic isthmus) * History of complicated peptic ulcer * Patient treated for less than 4 weeks for an ulcer * History of pancreatic surgery * Ongoing pregnancy (confirmed by a test beta-HCG) or breast feeding or absence of birth control * Patients with a active pathology or history that may interfere with the study in progress or the interpretation of its results according to the investigator * Patients with a history or suspicion of non-compliance with medical regimens or will be unable to complete the entire study * Treatment with systemic corticosteroids (excluding inhaled corticosteroids) * Participation in another interventional clinical study (RIPH1, clinical investigation or clinical trial) or exclusion period set after the study * Protected persons under legal guardianship or conservatorship