Pancreatic cancer is a malignant tumor of the gastrointestinal tract that is highly malignant, difficult to diagnose and treat, and about 90% of them are ductal adenocarcinomas originating from the epithelium of the adenohypophysis. Its morbidity and mortality rate has increased significantly in recent years. 5-year survival rate is <1%, and it is one of the malignant tumors with the worst prognosis. The diagnosis rate of pancreatic cancer in early stage is not high, the surgical mortality rate is high, and the cure rate is very low. The incidence of this disease is higher in men than in women, and the ratio of men to women is 1.5 to 2:1. Male patients are far more common than premenopausal women, and the incidence of postmenopausal women is similar to that of men. Clinical manifestations The clinical manifestations of pancreatic cancer depend on the location of the cancer, the early and late stage of the disease, the presence of metastasis and the involvement of adjacent organs. It is characterized by short duration, rapid progression and rapid deterioration. The most common symptoms are upper abdominal fullness, discomfort and pain. Although there is conscious pain, not all patients have pressure pain, and if there is pressure pain it is consistent with the site of conscious pain. 1. Abdominal pain Pain is the main symptom of pancreatic cancer, regardless of whether the cancer is located in the head or the tail of the pancreas. In addition to pain in the middle abdomen or left upper abdomen or right upper abdomen, a few cases complain of pain in the left and right lower abdomen, around the umbilicus or the whole abdomen, or even testicular pain, which can be easily confused with other diseases. When cancer involves visceral peritoneum, peritoneum or retroperitoneal tissues, there may be pressure pain in the corresponding area. 2.Jaundice Jaundice is an important symptom of pancreatic cancer, especially pancreatic head cancer. Jaundice is obstructive in nature, accompanied by deep yellow urine and clay-like stools, and is due to the invasion or compression of the lower end of the common bile duct. Jaundice is progressive and is unlikely to subside completely, although it can fluctuate slightly. The temporary reduction of jaundice is associated with the remission of inflammation around the jugular abdomen in the early stage, while in the late stage, the jaundice produced by the jugular abdomen tumor is more likely to fluctuate due to the ulceration and decay of the tumor invading the lower end of the common bile duct. Jaundice from pancreatic body tail cancer appears only when it reaches the head of the pancreas. Some patients with pancreatic cancer develop jaundice late in life due to liver metastases. About 1/4 of the patients have a combination of intractable pruritus, which is often progressive. The most common symptoms are loss of appetite, followed by nausea, vomiting, diarrhea, constipation or even black stool, and diarrhea is often steatorrhea. The loss of appetite is related to the lower end of the common bile duct and the pancreatic duct being blocked by the tumor, and the bile and pancreatic juice cannot enter the duodenum. Obstructive chronic pancreatitis of the pancreas leads to poor exocrine function of the pancreas, which also inevitably affects appetite. A small number of patients present with obstructive vomiting. About 10% of patients have severe constipation. Diarrhea due to pancreatic exocrine dysfunction: steatorrhea is an advanced but relatively rare manifestation. Upper gastrointestinal bleeding can also occur in pancreatic cancer, manifested as vomiting blood and black stools. Embolism of splenic vein or portal vein due to tumor invasion, secondary to portal hypertension, and occasionally ruptured hemorrhage of esophagogastric fundic varices are also seen. Unlike other cancers, pancreatic cancer is often associated with wasting and weakness at the initial stage. The abdominal mass is deep in the pancreas and is difficult to be felt in the posterior abdomen. Chronic pancreatitis can also be felt as a mass, which is not easily distinguished from pancreatic cancer. Symptomatic diabetes mellitus is the initial symptom of diabetes mellitus in a few patients, i.e., diabetes mellitus occurs before the main symptoms of pancreatic cancer, such as abdominal pain and jaundice, and the accompanying wasting and weight loss are mistaken as the manifestation of diabetes mellitus without considering pancreatic cancer. It is possible that pancreatic cancer has occurred in addition to the original diabetes. 7. Ascites usually appears in the late stage of pancreatic cancer, mostly due to peritoneal infiltration and spread of cancer. The ascites may be bloody or plasma, and the hypoproteinemia of advanced cachexia may also cause ascites.