CEACAM5 and pancreatic ductal adenocarcinoma: CEA: Carcinoembryonic antigen, CT: Computerized tomography, EUS: Endoscopic ultrasound, ERCP: Endoscopic retrograde cholangiopancreatography, FNA: Fine-needle aspiration, IPMN: Intraductal papillary mucinous neoplasm, MDCT: Multidetector computed-tomography, MRI: Magnetic resonance imaging, NAv: not available, PC: Pancreatic cancer, PDAC: Pancreatic ductal adenocarcinoma, PET: Positron emission tomography, US: Ultrasonography