Pancreatic cancer is characterized by its late detection, rapid development and poor prognosis, and is regarded as the stubborn bastion of medicine in the 21st century. 85% of patients are diagnosed with cancer that has infiltrated the surrounding large blood vessels and important organs and cannot be removed, with an average survival time of less than 6 months and a 5-year survival time of less than 5%. Recent domestic and international studies have shown that the survival time after pancreatic cancer depends on whether the margins are negative and whether the postoperative chemotherapy is good. The prognosis of patients with pancreatic cancer is not significantly different between patients with R2 resection and those who received only radiotherapy without surgery. In contrast, the 5-year survival rate of R0 resection combined with postoperative chemotherapy is around 20%. Therefore, for patients with pancreatic cancer, achieving a negative surgical margin has a direct impact on the patient’s prognosis. For pancreatic cancer of the head of the pancreas, radical pancreaticoduodenectomy is routinely performed, and there are four surgical margins, the bile duct dissection, the pancreatic neck dissection, the gastric dissection and the retroperitoneal margin. The retroperitoneal margin is the connective tissue 3-4 cm proximal to the right side of the superior mesenteric artery. Usually, the first 3 margins can be sent for intraoperative cryopathology, and then resected according to the cryopathology results until a negative surgical margin is achieved. However, for retroperitoneal margins, only postoperative pathology results can be relied upon. Therefore, it is very important to evaluate the resectability of surgery and determine the possibility of surgical resection before surgery. Usually, thin scan of the pancreas with enhanced CT and 3D reconstruction of the vessels are given preoperatively to determine the relationship between the tumor and the vessels. Currently, Loyer typing and LU score are used to determine the relationship between blood vessels and tumor, with Loyer typing A and B being resectable, C and D being potentially resectable, and E and F being unresectable. Especially for pancreatic adenocarcinoma of the leptomeningeal region, the intraoperative dissection of portal vein and mesenteric vessels is very important in order to achieve negative retroperitoneal margins. For those with preoperative CT Loyer staging C and D, the superior mesenteric artery is usually dissected out preoperatively and the pancreatic leptomeninges are resected along the right margin of the superior mesenteric artery, even in combination with portal vein or superior mesenteric vein vascular resection. The aim is to achieve a negative retroperitoneal dissection margin. In addition, combined postoperative chemotherapy is an important preservation to achieve 5-year survival. Prospective studies have shown that there is a significant difference in 5-year survival between postoperative combination chemotherapy and surgery alone in patients with pancreatic cancer. To achieve long-term tumor-free survival time, postoperative combination chemotherapy is usually required.