Abstract:Pancreatic cancer is the most malignant tumor of the digestive system. The diagnosis and treatment of pancreatic cancer have always been hot and difficult problems, and the concepts for its treatment are continuously being updated and improved in an arduous journey of exploration. At present, the hot issues of pancreatic cancer in clinical research include the transformation of multiple disciplinary team model in the treatment of pancreatic cancer, the definition of potentially resectable pancreatic cancer, the application of neoadjuvant chemotherapy, the way to improve the R0 resection, the utilization of minimally invasive surgery and the application value of enhanced recovery after surgery. Here, the above-mentioned issues are discussed, based on the latest literature and the authors’ own experience.

Abstract:Objective: To preliminarily summarize the experience in robotic-assisted pancreaticoduodenectomy (RPD) by the DaVinci system.
Methods: The clinical data of 18 patients undergoing RPD between November 2015 and January 2018 were retrospectively analyzed.
Results: In the 8 patients, the operative time was (450±30) min, intraoperative blood loss was (525±125) mL, with no requirement of blood transfusion; 1 case (5.6%) was converted to open surgery; the time for postoperative intestinal function recovery was (4.0±1.0) d, and the length of postoperative hospital stay was (16±4) d; postoperative complications occurred in 7 cases, including pancreatic fistula in 4 cases (22.2%) (of whom all were grade B pancreatic fistula), biliary fistula in 1 case, and intra-abdominal hemorrhage in 2 cases; no reoperation was required, and the postoperative mortality rate was 5%. Postoperative pathological results showed 3 cases of highly differentiated adenocarcinoma of the pancreas, 1 case of poorly differentiated ductal adenocarcinoma, 
3 cases of pancreatic serous cystadenoma, 2 cases of pancreatic mucinous cystadenoma, and 1 case of pancreatic ductal papillary myxoma; 2 cases of well-differentiated adenocarcinoma of the duodenum, 2 cases of duodenal villus tubular adenoma; 1 case of poorly differentiated adenocarcinoma of lower common bile duct, 2 cases of well differentiated adenocarcinoma of lower common bile duct, and 1 case of chronic pancreatitis. Of the 9 patients with malignant tumors, R0 resection was achieved in 8 cases and R1 resection was obtained in 1 case; the number of dissected lymph nodes was 16±4.
Conclusion: RPD is clinically safe and feasible, without increase of procedure-associated complications, and meanwhile, it can accelerate the postoperative recovery of the patients.

Abstract:Objective: To evaluate the clinical efficacy of laparoscopic spleen-preserving distal pancreatectomy (LSPDP) in treatment of benign and borderline tumors of the pancreas.  
Methods: The clinical data of 21 patients with benign or borderline tumors in the tail or body of the pancreas treated from August 2014 to August 2018 were retrospectively analyzed. Of the patients, 12 patients underwent LSPDP, and 9 patients underwent laparoscopic distal pancreatectomy with splenectomy (LDPS). The main clinical variables were compared between the two groups of patients.  
Results: There were no significant differences in operative time, intraoperative blood loss, length of hospital stay and intraoperative blood transfusion rates between the groups (all P>0.05). There were no significant differences in number of white blood cells and the percentage of neutrophils on postoperative day (POD) 1 and 7, as well as the ascitic fluid amylase concentration on POD 1 and 3 between the two groups (all P>0.05), but the platelet levels in 2 weeks and 3 months after operation were significantly higher in LDPS group than those in LSPDP group (both P<0.05). There was no significant difference in the incidence of postoperative complications between the two groups (P>0.05). 
Conclusion: Both LDPS and LSPDP can be used for benign and borderline tumors in the tail or body of the pancreas. LSPDP has certain superiority to LDPS in platelet stabilization.

Abstract:Objective: To investigate the clinical efficacy of using modified pancreatic duct-to-jejunal mucosa end-to-side anastomosis in pancreaticoduodenectomy (PD). 
Methods: The clinical data 80 patients undergoing PD from January 2016 to November 2018 were retrospectively analyzed. Of the patients, 39 cases underwent modified pancreatic duct-to-jejunal mucosa end-to-side anastomosis (modified group) and 41 cases underwent traditional pancreatic duct jejunum end-to-side mucosal anastomosis (traditional group). The main clinical variables and the incidence of postoperative pancreatic fistula and other complications were compared between the two groups.
Results: There were no significant differences in preoperative data between the two groups (all P>0.05). No significant differences were noted in total operative time and time for pancreaticojejunostomy, as well as the incidence of intra-abdominal hemorrhage, lymphatic leakage and delayed gastric emptying between the two groups (all P>0.05). The total incidence of pancreatic fistula in the modified group was significantly lower than that in traditional group [5.12% (2/39) vs. 24.4% (10/41), P<0.05], and in modified group, both cases were biochemical leakage and no B/C pancreatic fistula occurred, while in traditional group, biochemical leakage occurred in 2 cases and B/C pancreatic fistula occurred in 8 cases.
Conclusion: Modified pancreatic duct-to-jejunal mucosa end-to-side anastomosis can significantly reduce the incidence of pancreatic fistula after PD compared to traditional procedure. It has certain application value in clinical practice.

Abstract:Objective: To investigate the clinical characteristics, treatment and prognosis of  solid pseudopapillary tumor of the pancreas (SPTP).
Methods: The clinical data of 47 patients treated and pathologically confirmed as SPTP in the Department of General Surgery of the First Affiliated Hospital of Nanchang University from January 2007 to December 2018 were retrospectively analyzed.  
Results: Of the whole group, 11 patients were males and 36 were females, with the mean age of (32±15) years; the tumor was located in the head of the pancreas in 16 cases, in the neck of the pancreas in 8 cases, and in the body and tail of the pancreas in 23 cases; 21 cases (44.7%) were preliminarily diagnosed as SPTP by preoperative imaging examinations, and 6 cases underwent endoscopic ultrasound-guided fine-needle aspiration, by which, only 1 case (16.7%) was diagnosed as SPTP; 10 cases underwent pancreaticoduodenectomy, 12 cases underwent distal pancreatectomy combined with splenectomy, 8 cases underwent spleen-preserving distal pancreatectomy, 5 cases underwent middle segmental pancreatectomy, 10 cases underwent tumor enucleation, 1 case underwent duodenum-preserving pancreatic head resection, and 1 case underwent distal pancreatectomy combined with splenectomy, left nephrectomy, left adrenalectomy, and inferior vena cava thrombectomy. No reoperation was required and no death occurred in any of the patients. Immunohistochemical staining of the tumor specimens showed that positive expressions of PR, CD56 and NSE presented in most of them. The incidence of postoperative complications was 19.1% (9/47). Postoperative followed-up was conducted in 43 patients for (41.7±31.4) months, recurrence occurred in 1 patient and all these patients were alive.
Conclusion: SPTP is a potential low-grade malignant tumor, which is more likely to occur in young women. Its clinical manifestations are non-specific, and the diagnosis depends on histopathological examination. Surgical resection is the favored option, with a good prognosis.

Abstract:Objective: To investigate the effect of long non-coding RNA (lncRNA) HOST2 on proliferation, migration and invasion in pancreatic cancer cells and the mechanism.
Methods: The lncRNA HOST2 expressions in normal pancreatic epithelial cell line HPDE6-C7 and four different pancreatic cancer cell lines (Panc-1, AsPC-1, BxPC-3 and HPAC) were determined by qRT-PCR. Panc-1 cells were transfected with siRNA-HOST2 (si-HOST2 group) or scrambled sequence (negative control group), and then, the proliferative, migration and invasion abilities were analyzed by MTT assay, wound scratch assay and Transwell assay, and the expressions of epithelial–mesenchymal transition (EMT) associated proteins vimentin, Snail and Twist1 were measured by Western blot, respectively. The untransfected Panc-1 cells were used as blank control group.
Results: The expressions of lncRNA HOST2 were significantly increased in all the studied pancreatic cancer cell lines compared with HPDE6-C7 cells (all P<0.05). Compared with blank control group, the proliferative, migration and invasion abilities were all significantly reduced, and the expression levels of vimentin, Snail and Twist1 were all significantly decreased in si-HOST2 group (all P<0.05), while all above parameters showed no significant changes in negative control group (all P>0.05).
Conclusion: lncRNA HOST2 expression is up-regulated in pancreatic cancer cells, which is closely related to the proliferation, migration and invasion of pancreatic cancer, and its mechanism may be responsible for regulating the expressions of EMT-associated proteins.

Abstract:Objective: To assess the feasibility and safety of the interrupted running-through suture pancreaticojejunostomy though an animal experiment, for providing an experimental basis for clinical application.  
Methods: Twenty experimental pigs were equally randomized into study group and control group, and then underwent interrupted running-through suture or pancreatic duct-to-jejunal mucosa anastomosis to establish the pancreaticojejunostomy models. In the two groups, the time for pancreaticojejunostomy and the amylase level in the drainage tube on postoperative day 3 were recorded, and the anastomotic stomas were cut off one week after operation for pathological examination and immunohistochemical staining of smooth muscle actin (SMA). 
Results: The time to perform pancreaticojejunostomy was significantly reduced in study group compared with control group [(14.0±3.6) min vs. (20.9±3.2) min, P<0.05]. Although there was no statistical significance in the overall incidence of postoperative pancreatic fistula between the two groups (11.1% vs. 40.0%, P>0.05), only one case of grade A pancreatic fistula was noted in study group, while 2 cases each of grade B and C pancreatic fistula occurred in control group. The results of pathological examination showed that the inflammation in the anastomotic stoma was milder and the attachment of the jejunal wall to the pancreatic stump was tighter in study group than those in control group, and the positive rate of SMA immunohistochemical staining was significantly higher in study group than that in control group (88.9% vs. 20%, P<0.05).
Conclusion: Compared to the traditional pancreatic duct-to-jejunal mucosa anastomosis, the interrupted running-through suture pancreaticojejunostomy has the advantages of being easy to perform, reduced anastomosis time, reliable fixation, and decreased incidence of pancreatic fistula. So, it is recommended to be used in clinical practice.

Abstract:Objective: To investigate the value of pleural effusion combined with determination of serum monocyte chemotactic protein 1 (MCP-1) and soluble triggering receptor on myeloid cells 1 (sTREM-1) in early predicting the severity of acute pancreatitis (AP). 
Methods: The clinical data of 75 AP patients treated from December 2017 to December 2018 were collected. According to the severities of disease, the patients were divided into mild AP group (31 cases) and non-mild AP group (44 cases). The presence of pleural effusion at admission and other clinical variables were compared between the two groups, and the differences of serum levels of MCP-1 and sTREM-1 in the two groups of patients from the healthy subjects as well as their dynamic changes were also analyzed.
Results: There were no significant difference in sex, age and pathogenesis between the two groups, but the C-reaction protein (CRP) level, APACHE II score and incidence of pleural effusion were significantly higher and length of hospital stay was significantly longer in non-mild AP group than those in mild AP group (all P<0.05). The serum levels of MCP-1 and sTREM-1 in either mild AP group or non-mild AP group were significantly higher than those in healthy control group, but both in non-mild AP group were continuously and significantly higher than those in mild AP group (all P<0.05). Results of analysis of the predictive abilities for severity of AP by using CRP (≥98.55 mg/L), APACHE II score (≥8), pleural effusion and serum levels of MCP-1 (≥27.84 pg/mL) and sTREM-1 (≥0.39 ng/mL) alone or combinations showed that pleural effusion combined with serum MCP-1 and sTREM-1 had the highest estimation value (AUC=0.884, with a sensitivity of 93.2% and a specificity of 91.3%). 
Conclusion: Pleural effusion combined with serum MCP-1 and sTREM-1 detection has certain value for early predicting the severity of AP.

Abstract:Objective: To investigate the clinical efficacy and safety of endoscopic ultrasound (EUS)-guided puncture and drainage in treatment of infectious pancreatic necrosis (IPN). 
Methods: The clinical data of 60 patients with IPN undergoing EUS-guided puncture and drainage from January 2013 to December 2018 in the Third Xiangya Hospital of Central South University were retrospectively analyzed. The main vital signs, intraabdominal pressure (IAP), relevant clinical scores, laboratory results of the patients before and after treatment were compared, and the postoperative complications and followed-up of the patients were also analyzed.  
Results: In all patients after EUS-guided puncture and drainage, the vital signs, IAP, clinical scores and laboratory findings were significantly improved compared with those before treatment (all P<0.05). The treatment results were assessed as cure in 10 cases (16.7%), significantly improved in 46 cases (76.6%) and failed in 4 cases (6.7%). The overall effective rate was 93.3%. The incidence of serious complications was 16.7%, including pancreatic fistula in 3 cases, extraintestinal fistula in one case, intestinal perforation in 3 cases and hemorrhage in 3 cases. No procedure-related death occurred in any of them. Follow-up was obtained in 56 patients, and among them, the necrotic lesions were almost completely absorbed in CT scan, the clinical symptoms disappeared and the laboratory indexes showed no obvious abnormal results in 34 cases (60.7%), pancreatitis recurrence occurred within half a year in 10 cases, exocrine pancreatic insufficiency developed in 7 cases, and 4 cases died. 
Conclusion: EUS-guided puncture and drainage has excellent clinical efficacy and safety in treatment of IPN.

Abstract:Objective: To summarize the clinical features, pathogenesis, diagnosis and treatment as well as prognosis of hepatic portal venous gas (HPVG) associated with pancreatitis.  
Methods: The clinical data of 2 patients admitted and diagnosed as HPVG associated with acute pancreatitis were retrospectively analyzed. The relevant literature was reviewed and discussed.
Results: Case 1 was a male patient, 65 years of age, who was admitted due to abdominal pain for 10 d and then diagnosed as acute biliary pancreatitis. Abdominal CT did not show HPVG on admission. In this patient, the abdominal distension aggravated during the progress of the disease and signs of septic shock appeared one month after admission; abdominal CT reexamination showed HPVG and a large amount of walled-off necrotic debris in the pancreas and peripancreatic region. The patient was discharged on his own request because of progressive deterioration after 3-d conservative treatment, and died one week after discharge. Case 2 was a 70-year old woman who was admitted for severe abdominal pain for 1 d, and presented with septic shock on admission. CT showed pancreatitis with HPVG and scattered gas collections in the retroperitoneal space. Emergency laparoscopic exploration and converted open incision of the pancreatic capsule for decompression plus abdominal drainage were performed. The situation continued to deteriorate and multiple organ dysfunction could not be corrected after operation. The patient was discharged on her own request 4 d after operation and died on the same day. There were 11 cases of HPVG associated with acute pancreatitis reported by previous literature, of whom, the main manifestation was abdominal pain, and diagnosis of the disease was mainly dependent on CT and B ultrasound,  
6 cases died and 5 cases survived.
Conclusion: HPVG associated with acute pancreatitis is a rare condition, but it is always complicated with intestinal ischemia and necrosis, and results in a high mortality rate. Aggressive surgical management should be performed if conservative treatment fails.

Abstract:Objective: To investigate the clinical characteristics of mass-forming chronic pancreatitis and its diagnosis and treatment.  
Methods: The clinical data of 16 patients with mass-forming chronic pancreatitis treated from 2010 to 2018 were retrospectively analyzed.  
Results: Of the patients, 13 were males and 3 were females, with a median age of 48.5 years at their admission. The main clinical manifestations were abdominal pain and jaundice. The CA19-9 level was slightly elevated in 6 cases (47.85–235.95 U/mL). All patients underwent abdominal CT scan, and all presented with space-occupying lesion of the pancreas, of which, chronic pancreatitis was considered in 3 cases (18.8%); some patients underwent B ultrasound, ERCP or other examinations, which mainly suggested space-occupying lesion in the pancreas, but lacked characteristic evidence. All the 16 patients underwent surgical treatment, which included pancreaticoduodenectomy in 11 cases, distal pancreatectomy plus splenectomy in 4 cases, and local resection of the mass in the head of the pancreas with duodenum preservation plus internal drainage by pancreaticojejunostomy and choledochojejunostomy. The symptoms were significantly improved in all patients after surgery, and no complications such as pancreatic fistula, biliary fistula and abdominal hemorrhage occurred. Postoperative follow-up was conducted for an average of 3 years, and the surgical results were satisfactory.
Conclusion: The clinical and imaging features of mass-forming chronic pancreatitis are highly similar to those of pancreatic carcinoma, so it is more likely to be misdiagnosed. Comprehensive assessment should be made by combination of disease history, clinical manifestations, and laboratory results as well as imaging and histopathological findings. Surgical intervention can provide acceptable results.

Abstract:Objective: To evaluate the cost-effectiveness of nivolumab that has recently been approved for sale in China in treatment of chemotherapy-refractory advanced gastric cancer.  
Methods: Using the data obtained from the ATTRACTION-2 trial (330 cases for nivolumab group, and 
163 cases for placebo group), Markov model was created for simulation of the disease development process of chemotherapy-refractory advanced gastric cancer. The costs, life-years (LY) and quality-adjusted life-years (QALY) in each group were analysed, then the incremental cost-effectiveness ratio (ICER) was calculated to evaluate the cost-effectiveness, and subgroup analysis was also performed based on the expression of programmed death-ligand 1 (PD-L1). The variables were further valued by sensitivity analysis to assess the reliability of the model. 
Results: Among PD-L1 positive patients, the overall health output gained in nivolumab group was 0.357 QALY (0.526 LY) at a cost of 221 171 yuan, and in placebo group was 0.251 QALY (0.368 LY) at a cost of 40 866 yuan; the ICER for the nivolumab group compared with placebo group was 1 700 991 yuan/QALY. Among PD-L1 negative patients, the overall health output gained in nivolumab group was 0.545 QALY (0.845 LY) at a cost of 
333 195 yuan, and in placebo group was 0.403 QALY (0.63 LY) at a cost of 90 285 yuan; the ICER for the nivolumab group compared with placebo group was 1 710 634 yuan/QALY. The ICER values of nivolumab treatment were greater than that of willingness-to-pay (178 980 yuan) in both subgroups. The probabilistic sensitivity analysis showed that the possibility of cost-effectiveness of nivolumab was 0. One-way sensitivity analysis indicated that the most influential parameter was the price of nivolumab. 
Conclusion: Nivolumab does not achieve cost-effectiveness compared to placebo for chemotherapy-refractory advanced gastric cancer at current health care environment in China. However, nivolumab can provide a survival benefit to the patients, and its economical effectiveness can be improved by means such as implementing charity care program and medical insurance coverage. 

Abstract:Hereditary pancreatitis is a rare type of acute or chronic pancreatitis with clinical symptoms similar to pancreatitis caused by other causes. In 1996, Whitcomb firstly reported that mutation of PRSS1 is the cause of hereditary pancreatitis. Subsequently, SPINK1, CFTR and CTRC were reported to be associated with hereditary pancreatitis, but whether they are the causative genes of hereditary pancreatitis remains controversial. PRSS1 encodes cationic trypsinogen, and mutations in this gene may result in increased trypsin activation or reduced inactivation, causing clinical pancreatitis. More than 20 pathogenic mutations of PRSS1 have been reported, and the most common mutation sites are R122H, N29I and A16V. The onset of hereditary pancreatitis occurs at a younger age, and usually before the age of 20, with an average onset age of 10 years. The average age for developing chronic pancreatitis is 20 years, and the risk for progressing to pancreatic cancer is dramatically increased after 
50 years of age. Management of patients with hereditary pancreatitis includes avoidance of environmental triggers, therapy for endocrine and exocrine insufficiency, pain management, endoscopic or surgical treatment and surveillance for pancreatic cancer. Here, the authors mainly address the research progress of the pathogenesis and treatment as well as disease management of PRSS1-related hereditary pancreatitis.

Abstract:Groove pancreatitis (GP) is a type of chronic pancreatitis that mainly affects the groove area of the pancreas. Owing to its insidious onset, most physicians lack a basic understanding of GP, thus easily leading to a misdiagnosis. The pathogenesis of GP is still unclear, and its clinical manifestations are very similar to those of pancreatic carcinoma, which mainly include postprandial upper abdominal pain, nausea, vomiting and progressive weight loss. At present, there is no unified diagnostic criteria. For highly suspected GP, some scholars suggest a staged treatment method. Therefore, the authors discuss the latest advances in GP research by extracting the relevant literature, so as to improve the diagnosis and treatment of this condition.

Abstract:Pancreatic fluid collections (PFC) are common complications of severe acute pancreatitis (SAP). They often cause systemic inflammatory response syndrome (SIRS) and intra-abdominal hypertension (MOF), and even abdominal compartment syndrome (ACS) which is difficult to be corrected, and thereby develop multiple organ failure (MOF) and death. With the deepening of pathophysiological research and emergence of a large number of evidence-based medical data of SAP, the concept of minimally invasive and injury-control staged treatment of SAP has been confirmed and recommended by most guiding documents. However, puncture timing and location of percutaneous catheter drainage (PCD) guided by ultrasound or CT as the initial and core minimally invasive method for PFC are still controversial. How to achieve the “individualized” and “accurate” management of patients according to the guidelines remains to be further explored.