Pancreatic cancer is one of the common malignant tumors of the digestive system with a high degree of malignancy and poor prognosis. The peak incidence of the disease is 70-90 years old, with a similar proportion of men and women. There is no clear cause for the development of pancreatic cancer, but there are risk factors associated with the development of pancreatic cancer, such as smoking, high-fat diet, obesity and alcohol consumption. Also, a family history of pancreatic cancer is associated with a much higher likelihood of developing the disease. In the molecular level of tumor research, it is suggested that mutations in p16 gene and BRCA-2 gene are related to the development of pancreatic cancer. Clinical manifestations Pancreatic cancer may not have any clinical manifestations in the early stage, but as the tumor grows, related symptoms may gradually appear. According to the different tumor growth sites, pancreatic cancer can be roughly divided into pancreatic head and neck cancer and pancreatic body and tail cancer. The main clinical manifestations of the former are painless jaundice, yellow sclera, itchy skin, deepening of urine color like strong tea or soy sauce, and pale stool color or white clay-like, which are caused by external pressure obstruction due to tumor invasion of bile duct. The latter is mainly manifested as unbearable low back pain in the form of banding, which is mostly caused by tumor invasion of the posterior peritoneal plexus. On the other hand, the pancreas is not only an endocrine organ but also an exocrine organ, so the occurrence of tumor may also cause damage to its endocrine and exocrine functions. The most common ones are the newly emerged endocrine function abnormalities, mainly type 2 diabetes mellitus, and the damaged exocrine functions such as steatorrhea and dyspepsia. Laboratory and imaging diagnosis Tumor markers CA199, CA125, CEA and pancreatic carcinoembryonic antigen are considered to be related to pancreatic cancer, among which CA199 is the most commonly used clinical index. CA199 is the most commonly used marker in clinical practice. CA199 is usually elevated in other diseases such as inflammation of the biliary system, benign stenosis of the bile duct and pancreatitis, so its specificity for pancreatic cancer diagnosis is not high and it is only used as an auxiliary diagnostic reference indicator. Imaging examination is the main means to diagnose pancreatic cancer, including abdominal CT, MRI/MRCP and ERCP. With the continuous development of CT equipment and the widespread use of multi-row spiral CT, abdominal CT has become the most important method to diagnose pancreatic cancer. It can not only detect the occupying lesions of the pancreas, but also perform pre-surgical staging, assess the resectability of surgery, and provide the corresponding clinical basis for the subsequent treatment of patients. For patients with pancreatic cancer combined with biliary tract infection, ERCP can not only be used for diagnosis, but also can temporarily relieve biliary tract obstruction, usually drainage, relieve biliary tract infection symptoms, and play a certain therapeutic effect. With the rise of EUS in recent years, EUS has been increasingly emphasized in the diagnosis of pancreatic cancer and can be used as a supplement to abdominal CT diagnosis. Meanwhile, for patients who cannot undergo surgery, FNA can be performed under the guidance of EUS to obtain cytological and histological diagnostic evidence, so as to prepare for radiotherapy. 3.Surgical treatment Once pancreatic cancer is diagnosed, surgical resection is the only radical way to cure it. According to the location of tumor growth, pancreatic cancer surgery can be divided into standard pancreaticoduodenectomy, pylorus-preserving pancreaticoduodenectomy, pancreatic tail resection, pancreatic segmental resection and so on. For surgical treatment, the most critical thing is the resectability of the tumor. The resection rate has been low because most patients are already in the middle and late stage of the tumor when they are diagnosed. On the other hand, the surgery of pancreatic cancer is traumatic and difficult, and its surgery-related mortality rate was generally high in the past. However, with the improvement of surgical techniques, medical devices and perioperative treatment, the surgery-related mortality rate has been reduced to less than 5%. For pancreatic head tumors assessed as resectable by preoperative imaging, standard pancreaticoduodenectomy should be performed, including resection of the head of the pancreas, duodenum, gallbladder, distal stomach, distal bile duct below the opening of the cystic duct, proximal jejunum, and peripancreatic lymphatic fatty nerve tissue, followed by reconstruction of gastrointestinal continuity, including biliary-enteric anastomosis, gastrointestinal anastomosis, and pancreatic-enteric anastomosis. In patients with pancreatic cancer with vascular invasion and assessed as resectable on preoperative imaging staging, the invaded vessels can be combined with standard pancreaticoduodenectomy to reconstruct the vessels, which has also been widely performed. Thus, for the present, the surgical resection rate of pancreatic cancer has improved compared to the previous one. The most common recent complications in postoperative patients are pancreatic leakage or pancreatic fistula, and the removal of lymphatic fatty nerve tissue in the posterior peritoneum will cause different degrees of gastrointestinal dysfunction, such as intractable diarrhea and paralytic intestinal obstruction, etc. Secondary diabetes mellitus is also a common postoperative complication, which may require long-term standardized insulin therapy. 4.Adjuvant treatment For post-operative pancreatic cancer patients, it is recommended to routinely perform post-operative radiotherapy treatment after 4 to 8 weeks after surgery, followed by radiotherapy after a period of adequate systemic chemotherapy. Currently, the first-line regimen is 5-Fu or gemcitabine for systemic chemotherapy with local radiotherapy. For advanced pancreatic cancer that cannot be surgically resected or has distant metastases, the combination of radiotherapy + chemotherapy should also be used to prolong the survival cycle of patients. Palliative and supportive treatment for advanced pancreatic cancer For patients with advanced pancreatic cancer, the aim of treatment is to prevent and relieve pain while ensuring a satisfactory quality of life. For example, patients with biliary obstruction can be treated by ERCP with biliary stent placement, PTCD or open biliary intestinal diversion; for gastro-jejunal diversion, percutaneous endoscopic gastrostomy placement or endoscopic intestinal stent placement for gastro-jejunal obstruction due to tumor compression or invasion; for severe abdominal pain caused by tumor, EUS or CT-guided abdominal plexus destruction can be performed. In conclusion, surgical resection is the only radical treatment for pancreatic cancer, supplemented by postoperative radiotherapy, which is the most effective treatment option at present. It is believed that with the further development of medicine and in-depth research on pancreatic cancer, pancreatic cancer will be conquered by mankind.