PET-CT can be used to diagnose pancreatic ductal adenocarcinoma, but it cannot confirm the diagnosis of pancreatic ductal adenocarcinoma, and it is only a kind of imaging screening; the confirmation of the diagnosis needs to rely on pathology. PET-CT is positron emission tomography (PET-CT), which integrates PET and CT, with PET providing detailed molecular information on the function and metabolism of the lesion and CT providing precise anatomical localization of the lesion, and a single imaging can obtain tomographic images of the whole body in all directions, which is sensitive, accurate, specific, and precise in localization. PET-CT can be used in the diagnostic process of pancreatic cancer, but it cannot confirm the diagnosis of pancreatic cancer, let alone pancreatic ductal adenocarcinoma. The diagnosis of pancreatic ductal adenocarcinoma needs to rely on pathological examination, such as pathologic biopsy. If pancreatic cancer is suspected, it is recommended to go to a regular hospital to evaluate the condition, integrate multiple means to evaluate and diagnose the disease, and follow the doctor’s instructions to cooperate with the treatment, in order to improve the patient’s prognosis and prolong the survival period.