In some medically advanced countries or regions, more and more physicians are using metal stents to treat malignant obstruction of the gastrointestinal tract. From October 2002 to November 2004, 24 cases of gastric or duodenal obstruction caused by malignant tumors of the gastrointestinal tract were treated by endogastric stent placement in our general surgery department. Clinical data and methods General data: Of the 24 patients in this group, 8 were male and 16 were female. The age ranged from 51 to 82 years old, with an average of 69.9 years old. The primary disease was gastric cancer in 19 cases (11 cases of anastomotic recurrence), pancreatic cancer in 4 cases, postoperative bile duct cancer in 1 case, the site of obstruction was located in the gastric sinus and pylorus in 9 cases, the original surgical anastomosis in 11 cases (7 cases of Bi II type, 4 cases of Bi I type), the descending duodenum in 3 cases, and the ascending duodenum in 1 case. Except for 4 cases of pancreatic cancer diagnosed by tumor markers and imaging, the remaining 20 cases were pathologically confirmed. On admission, all patients had clinical manifestations of upper gastrointestinal obstruction, such as frequent vomiting, abdominal distention, and weight loss. After admission, gastrointestinal decompression was given, and the daily drainage was between 600 and 2000 ml. All patients were mostly examined by gastroscopy or upper gastrointestinal imaging to clarify the site of obstruction. Operation method After 2 to 4 days of gastrointestinal decompression and other treatments, the patient was given a detailed explanation of the procedure and the advantages and disadvantages of the procedure, and after obtaining the consent of the patient or his family, metal endoprosthesis placement was started. The specific steps are as follows: 1. Insert a gastroscope or lateral duodenoscope to the proximal end of the obstruction, insert a contrast catheter through the working channel of the scope, inject 38% pantothenic glucosamine contrast agent against the stenosis, and understand the extent of the stenotic segment under X-ray fluoroscopy. 2.Insert the super-slip guidewire through the stenotic segment, the contrast catheter reaches the jejunum under the guidance of the guidewire, withdraw the super-slip guidewire, enter the super-rigid guidewire along the catheter to the jejunum, and exit the catheter and endoscope respectively. 3. Select the metal stent of suitable length according to the stenotic segment, and the ends of the stent must exceed the stenotic segment by 2-3 cm after release. if the stenotic segment is 3 cm, a 7-8 cm stent is required. The stent selected in this group was a domestic memory alloy mesh endoprosthesis with a length of 6-12 cm and a maximum diameter of 2 cm. the stent was delivered to the stenotic segment along a superhard guidewire, and the site was determined under X-ray fluoroscopy according to the residual contrast agent, and finally the stent was released. The stenosis was in the range of 2-6 cm in all cases. 24 metal stents were placed in the intended site. There were 4 cases of double stents in the whole group, 3 cases of duodenal obstruction after biliary metal stent placement due to pancreatic head cancer, and 1 case of double intestinal stent placement at the same time because of recurrence of gastric cancer and infiltration of the mass to compress the input and output loops, and one stent was placed in each loop. The rate of nausea and vomiting disappeared after 3 days of stent placement was 23/24 (95.8%), the rate of weight gain was 19/24 (79.2%) and the rate of gastrointestinal decompression was 0/24 (0%) in the first month after surgery, and one case still had vomiting after eating at the follow-up after one month. All patients were given fluid on the first day after surgery and semi-liquid on the third day, and were discharged after two more days of observation. Nine cases had mild to moderate abdominal discomfort or pain after surgery, which were not treated with painkillers and other drugs and resolved on their own after 2 to 3 days. There were no complications such as perforation or bleeding due to stent placement. The upper gastrointestinal tract was followed up for 1 to 24 months after surgery, and dilute barium examination of the upper gastrointestinal tract was done to observe the patency of the gastrointestinal tract. 21 cases were followed up, and only 2 cases developed obstruction at the 6th and 9th month after surgery, respectively. The obstruction was caused by granulation and tumor growth, and no displacement of the metal stent was detected by radiography. The lesions that cause malignant obstruction of the gastroduodenum are mostly gastric cancer, duodenal cancer, pancreatic cancer, infiltrative metastasis of hepatobiliary or other tumors, and recurrence of tumors in the gastrointestinal anastomosis. Patients often have severe vomiting and are unable to eat. The traditional method for patients who cannot undergo radical surgery is to perform gastrointestinal short-circuit surgery or gastrostomy or enterostomy, but at this time, patients often have poor systemic conditions and cannot tolerate surgery or are unwilling to operate, and can only rely on gastrointestinal decompression and intravenous nutrition to maintain life, which is not only painful for patients but also costly. The palliative treatment of malignant obstruction of gastroduodenum with metal endoprosthesis was applied to the clinic in the early 1990s. With the progress of endoscopic technology, especially the improvement of material performance, endoscopic, metal stents for the treatment of gastrointestinal obstruction, the application is becoming more and more widespread, and the clinical results are getting better and better. and stent refinement, clinical applications are becoming more and more common. In China, the 16 cases treated by Fan Zhining et al. in 2004 also achieved satisfactory results. In this group of 24 cases, the obstructive symptoms were rapidly relieved after stent placement, and the feeding function was restored, which obviously improved the quality of life of the patients. All 24 cases in this group were successful, and no complications such as perforation, bleeding and stent displacement occurred, indicating that this treatment method is safe and effective. We believe that when endoprosthesis is performed, gastrointestinal decompression should be performed first, and hypertonic saline gastric lavage is needed to reduce edema if necessary. Intubation through endoscopy must be performed with a super-slip guidewire first through the stenotic segment and then catheter follow-up; direct insertion of the catheter into the stenotic segment should not be avoided to avoid perforation. Especially in cases with significant stenosis, special attention should be paid to confirm that the catheter can follow up only after the superslip guidewire has passed through the stenosis. An imported zebra guidewire can be used to facilitate the passage of the stenotic segment. The catheter reaches the distal jejunal segment as far as possible, which ensures successful stent release. Withdraw the super-slip guidewire and then replace it with a super-rigid guidewire to reach the jejunal segment because the super-rigid guidewire is not easily coiled in the stomach and can hook the intestinal segment at the distal end, which is not easy to slip out. Exit the catheter and endoscope separately. The positioning of the placed stent is customarily positioned by the author according to the residual contrast agent and intestinal gas under X-ray fluoroscopy. If it is difficult, a metal sheet can be placed on the body surface at the midpoint of the stenotic segment when the contrast agent is injected, and when the stent is placed, the midpoint of the stent can be placed at the position of the metal sheet. The length of the stent should exceed the proximal and distal ends of the stenosis by 2 to 3 cm each to prevent the tumor from growing in from both ends. When releasing the stent, attention should be paid to the retraction of the stent to avoid being out of place after complete release. Finally, the patient should be allowed to take oral contrast and observe the effect of the stent. It is easy for a physician who has experience in ERCP treatment to master the above points, similar to the operation of placing biliary metal stents. The placement of metal stents for malignant obstruction of the gastroduodenum should be strictly controlled to avoid depriving the patient of the opportunity of tumor eradication. ① Preoperative ultrasound, CT, MRI, etc. or physical examination clearly have distant metastasis and cannot perform radical surgery. ②Tumor is found to extensively infiltrate the gastric wall during laparotomy, and gastrointestinal anastomosis short-circuiting cannot be performed or short-circuiting is prone to anastomotic leakage. ③The patient’s general condition is very poor or accompanied by serious cardiopulmonary and other medical disorders, which cannot tolerate open surgery. ④Patients and family members refuse open surgery. This method should be considered only if one of the above conditions is present. However, the development of tumor growth, infiltration and compression will still affect the overall quality of life of patients and shorten the survival period. Therefore, after the patient’s systemic condition is improved, interventional chemotherapy, systemic chemotherapy or radiotherapy should be actively cooperated to improve the survival time of patients more effectively. In conclusion, the treatment of gastroduodenal malignant obstruction with metal endoprosthesis is safe, minimally invasive, with fast results and few complications, which improves the patients’ quality of life and increases the survival time, and at the same time increases the means for clinicians to treat gastroduodenal malignant obstruction.