In 1988, Warshaw [1] reported for the first time that spleen-preserving distal pancreatectomy (SpDP) was performed in patients with pancreatic trauma. In 1988, Warshaw [1] first reported spleen-preserving distal pancreatectomy (SpDP) in patients with pancreatic trauma, which has attracted great attention and gradually gained acceptance in the surgical community. So far, there are two types of spleen-preserving distal pancreatectomy: SpDP with resection of splenic vessels and SpDP with preservation of splenic vessels, among which the former SpDP with preservation of splenic vessels has been widely adopted, especially in laparoscopic surgery, because it requires relatively low surgical technique and can be easily mastered. In this study, we retrospectively analyzed the postoperative gastroscopic and CT examinations and other clinical data of 13 patients who underwent SpDP with resected skin vessels to investigate the changes of blood flow in the postoperative gastric and splenic regions of this procedure and the long-term safety of this procedure. Methods General data There were 11 cases of pancreatic body caudal resection with splenic vascularization and preservation of the spleen in our hospital, with a male-to-female ratio of 3:8 and a mean age of 50.7±11.6 years. All 11 cases had preoperative tumor markers within the normal range, and all imaging examinations were considered benign, and all patients had no history of chronic liver disease or gastrectomy in the preoperative examination. The surgical approach was performed by using a median incision in the upper abdomen or an oblique incision under the left costal margin to enter the abdomen, incising the gastrocolic ligament outside the vascular arch of the gastric omentum, entering the omental sac, pulling the stomach upward, fully exposing the caudal part of the body of the pancreas, exploring the extent of the lesion and its relationship with the pancreas and surrounding organs, and routinely examining the pathological nature by intraoperative frozen section, paying attention to protecting the right arterial vein of the gastric omentum and the main trunk of the left arterial vein of the gastric omentum and its anastomotic branches. The posterior peritoneum was opened beneath the pancreas, the posterior part of the pancreas was freed from the posterior abdominal wall, the pancreas and the posterior splenic artery were severed about 2 cm to the right of the lesion, and the pancreas section was made in the shape of a fish mouth, and the main pancreatic duct was ligated and the pancreas section was sutured with mattress sutures. The posterior gastric artery, left gastric omental artery and short gastric artery were ligated and cut off before the splenic artery emanated from them, and the disconnected vessels were excised in whole along with the tail of the pancreatic body. After closely observing the splenic color and touching the pulsation of the above arteries, and confirming that there was no obvious splenic infarction, drainage was placed and the operation was ended by closing the abdomen. Patients were reviewed every 3 months for the first year after surgery and every 6 months after the second year for symptoms of vomiting blood and black stool, and if necessary, stool routine was checked to assess whether there was gastrointestinal bleeding, and CT-enhanced scans of the upper abdomen and fiberoptic gastroscopy were performed at the 3rd and 12th months after surgery to observe the morphological blood supply to the spleen, the perigastric and submucosal vessels in the esophagus of the gastric wall. The diagnosis of varices was based on enhanced CT showing gastroesophageal or peripheral veins greater than 5 mm in diameter, and the diagnosis of submucosal varices by fiberoptic gastroscopy was based on the finding of earthworm-like or massed submucosal bulges in the gastroesophagus. In the 11 cases of pancreatic caudal resection with splenic vascularization and preservation of the spleen, the average operative time for the whole group was 2.8±0.4 hours and the average intraoperative blood loss was 404.5±101.1 mL. There were no cases of intraoperative blood transfusion. The postoperative pathology reported 11 cases were all benign, including 3 cases of plasmacytic cystadenoma, 3 cases of mucinous cystadenoma, 2 cases of intraductal papillary mucinous tumor, 1 case of non-functional endocrine tumor, 1 case of islet cell tumor, and 1 case of chronic pancreatitis. There were 2 cases of postoperative complications, both of which were pancreatic leaks, and they were discharged after conservative treatment, and no other complications occurred in the whole group. The average number of postoperative hospitalization days for the whole group was 16.1±6.9 days. There were no fatal cases in the whole group. All 11 cases were examined by Doppler ultrasound for splenic blood supply before discharge, and no obvious signs of splenic infarction were seen. Postoperative follow-up was 37.4±17.7 months, with the shortest follow-up time of 12 months, and no obvious signs of tumor recurrence and metastasis were seen in the tumor patients. Enhanced CT examination at 3 months postoperatively revealed splenomegaly in 4 patients (36.4%), perigastric varices in 3 patients (27.3%) and submucosal varices in 1 patient (9.1%), among which 2 patients had both splenomegaly and perigastric varices (1 of them had splenomegaly, perigastric and submucosal varices at the same time). At 12 months postoperatively, among the four patients with splenomegaly, one had remission of splenomegaly and the other three remained basically stable, with no new cases of splenomegaly; the CT findings of the three cases of perigastric varices showed stable varices without progression and no new perigastric varices; the CT findings of the patients with submucosal varices showed stable splenomegaly, perigastric and submucosal varices with no significant progression. Gastroscopy at 3 months showed varices in the gastric wall in one patient (the same patient with submucosal varices detected by CT), and gastroscopy at 12 months showed no progression of varices in the gastric wall. No esophageal or periesophageal varices were found in the whole group by CT and gastroscopy, and no patient showed upper gastrointestinal bleeding symptoms such as vomiting blood and black stools during the follow-up period. Discussion Although the spleen is not a vital organ, it plays an important role in maintaining normal blood cell levels and immune function in the human body, etc. With a better understanding of it, more and more surgeons are trying to preserve the spleen when performing pancreatic body tail resection. SpDP can be divided into two types according to whether the splenic vessels are preserved or not: SpDP with resection of the splenic vessels and SpDP with preservation of the splenic vessels; compared with the latter, the former is less demanding, less difficult, less time-consuming and easier to master, especially for patients with adhesions between the splenic veins and the pancreas and difficult separation. Although some of the early literature [2, 3] reported that preserving the spleen increases the occurrence of postoperative complications and prolongs the hospital stay, in recent years, with the promotion of this procedure and the increase of related reports, a lot of literature shows that SpDP is not only safe, but also has some advantages compared with traditional DP. First, because the spleen plays an important role in the human immune system, preserving the spleen may reduce the incidence of infection in patients after pancreatic body tail resection to a certain extent; both Shoup M et al [4] and Carrère N et al [5] found that SpDP significantly reduced the incidence of postoperative infectious complications and serious complications compared with conventional DP. Secondly, preserving the spleen can better maintain blood cell levels, such as platelets, which can better avoid a series of thrombotic complications associated with postoperative hypercoagulability, and Kimura W et al [6] found that postoperative platelet counts were significantly lower in SpDP than in conventional DP. The disadvantage is that the above studies all focused on the short-term complications and safety of SpDP, while SpDP surgery is currently mainly used to treat patients with benign or low-grade malignant tumors of the tail of the pancreatic body, and this series of diseases mostly have a good prognosis, and it is equally important to evaluate the long-term complications of the surgery for these patients. [7, 8] first found that a group of long-term complications manifested by perigastric and gastric wall varices and splenomegaly can occur after SpDP with resection of splenic vessels. They observed 10 patients after SpDP with resection of splenic arteries (mean follow-up time 92 months) and found 7 cases (70%) of perigastric vascular varices and 2 cases (20%) of submucosal vascular varices by CT scan and gastroscopy. Upper gastrointestinal bleeding occurred in l of these cases, which led them to question the safety of the procedure. This is a group of symptoms similar to regional portal hypertension, the basis of which should be due to the existence of the splenic artery and the double circulation system of the left artery and short artery of the gastric omentum in the spleen itself. The difference is that most of the common clinical regional portal hypertension is caused by pancreatic inflammation or tumor causing blockage of the splenic vein, while the splenic artery is mostly unobstructed. Therefore, the exact mechanism of the occurrence of splenic artery after resection of splenic vessels in SpDP is unclear and needs to be further investigated. marn et al [9] compared patients with regional portal hypertension and cirrhotic portal hypertension and found that the occurrence of varices in patients with regional portal hypertension was limited to the short gastric vein and the gastroretinal vein. The results of this study also showed that 3 cases (27.3%) had perigastric varices and 1 case (9.1%) had gastric submucosal varices at 3 months after SpDP with resection of splenic vessels in 11 cases, and no esophageal or periesophageal varices occurred. Eleven cases (29.7%) of varices, 12 cases (32.4%) of splenomegaly, and 3 cases (8.1%) of submucosal varices, but no esophageal or periesophageal varices occurred. These data are lower than those reported by the author than those reported by Miura F et al. after surgery. The most serious outcome of submucosal varices in the stomach is the possibility of rupture of the varices leading to severe upper gastrointestinal bleeding, which can be life-threatening, and it is for this reason that Miura et al. questioned the safety of the SpDP procedure with resection of the splenic vein. Although neither the present study nor the report by Tien YW et al. found any postoperative upper gastrointestinal bleeding in patients, this possible complication should not be taken lightly. Also, considering the possibility that perigastric varices may progress to submucosal varices [11], patients with perigastric or submucosal varices found at postoperative follow-up should be reviewed regularly with enhanced CT and gastroscopy to observe the varices, and if there is progression, the follow-up period should be extended and closely observed. Although at 3 months in this study, 3 cases had perigastric varices and only 1 case had gastric submucosal varices, and the situation remained stable at 12 months postoperatively in the same way as at 3 months postoperatively, and no upper gastrointestinal bleeding occurred during the follow-up period, the author believes that these patients should be followed up regularly for a long time after surgery to be alert to the occurrence of variceal rupture and bleeding. Conclusion In conclusion, resection of splenic vessels and preservation of the spleen by pancreatic body caudotomy may cause postoperative changes in blood flow in the splenogastric region, such as splenomegaly, perigastric and submucosal varices, but there is no evidence to confirm that upper gastrointestinal bleeding is its long-term complication, and therefore, this procedure is safe and feasible.