Analysis Of Risk Factors For Postoperative Gastroparesis In Patients With Distal Gastrectomy And The Role Of Cajal Interstitial Cells In Its Pathogenesis

BackgroundGastric cancer is one of the most common malignancies in the world.The incidence and mortality of gastric cancer in male were respectively ranked fourth and third in all tumors,accounting for 10.1% of all male malignancies,and ranked fifth in female,accounting for 7.2% of all female malignancies.The prevalence of gastric cancer in our country is more severe,accounting for about 12.7% of the total population of malignant tumors.With the application of clinical laboratory technology,imaging technology,immunohistochemistry,biochemical technology,tumor targeting drugs and the rapid development of surgical skills and surgical related equipment,the detection and treatment of gastric cancer has made significant progress.However,due to the presence of postsurgical gastroparesis syndrome(PGS),it is still difficult for the patients to enjoy the normal life after radical resection of distal gastric cancer.PGS is a complex disorder characterized by postprandial nausea,vomiting,bloating and epigastric discomfort without mechanical gastric outlet obstruction,which is often caused by upper abdominal surgery,especially gastrectomy or pancreatectomy,orsometimes by lower abdominal surgery,such as gynecological surgery,obstetric surgery and colorectal surgery.The incidence of PGS is about 0.4-19.0%.It often takes a very long time before the patients' recovery of gastrointestinal function.Most of the PGS patients were frequently presented with weight loss or malnutrition,requiring hospitalization and prolonged parenteral nutrition.Therefore,analysing the risk factors of PGS after radical resection of distal gastric cancer and preventing its occurrence are of great value for the patients and their family.At present,interstitial cells of Cajal(ICC)have been widely demonstrated as pacemakers and transducers for gastrointestinal slow wave activity.According to the literature,there are many clinical reports in the literature on the reduction of ICC in diabetic gastroparesis and idiopathic gastroparesis.However,the literatures about performance of ICC in PGS patients are rare.In clinical work,we can often see that for the patients with gastric cancer who have similar age,illness and treatment,the outcome is often significantly different.And,sometimes,PGS occurs after obstetrics and gynecology surgery.Therefore,we intend to experiment whether ICC in PGS patients' gastric tissue is reduced,which caused the poor tolerance to the changes in the surrounding environment after surgery.Objective1.To find out the clinical risk factors related to the occurrence of PGS in patients underwent distal gastrectomy.2.To observe the changes of ICC in gastric tissue from patients with postsurgical gastroparesis after distal gastrectomy.MethodsFrom January 2014 to December 2016,a total of 380 patients underwent radical distal gastrectomy for gastric cancer at the department of general surgery of the Fourth Military Medical University,Tang Du Hospital,were classified into 2 groups according to the occurrence of PGS(case group,n=20;control group,n=360).The diagnosis of PGS is based on the patient's clinical manifestations,imaging examinations,endoscopy,and upper gastrointestinal imaging.1.The fellow data of the two groups were recorded.Basic characteristics: gender,age,body mass index,accompanied disease,ASA anesthesia grading,NRS2002 score,preoperative chemotherapy,preoperative pylori obstruction,postoperative blood glucose and daily infusion volume;Oncology data: tumor location,tumor size and TNM staging;Surgical information: surgical approach,anastomosis,operation time,intraoperative blood loss volume,intraoperative blood transfusion,retrieved lymph node,proximal resection margin,distal resection margin and residual stomach size;Nutritional indicators: the value of hemoglobin and albumin preoperative and postoperative day 1,day 3,day 5;Inflammatory indicators: the value of CRP and PCT postoperative day 1,day 3 and day 5;white blood cell count,neutrophil percentage and lymphocyte percentage preoperative and postoperative day 1,day 3,day 5.All data analyses will be performed using the SPSS 19.0 statistical package.Normally distributed continuous variables will be presented as mean and standard deviation((x|-)±s)and compared using the t-test if normally distributed.Categorical data will be presented as number and percentages and compared using the Pearson ?2 test or the Fisher exact test as appropriate.A two-sided P<0.05 will be considered statistically significant.2.40 patients in the control group were matched according to age,sex,BMI and pathological stage.Full-thickness of gastric antral and body tissues of the 20 patients with PGS and 40 matched patients in the control group were immunolabeled with c-kit antibody and the ICC number was observed at high power fields.Results1.The comparison of clinical variables between the two groups.The age of patients in PGS group was significantly higher than that in the control group(64.1±8.9 vs55.5±10.2,P=0.005),the difference was statistically significant.The proportion of patients with blood glucose concentration ?8mmol/L in PGS group was significantly higher than that in control group(25% vs 6.1%,P=0.009),the difference was statistically significant.The value of albumin in PGS group was significantly lower than that in the control group(P<0.05).There were no statistically significant differences in the other variables between the two groups.2.The comparison of immunohistochemical results between the two groups.The expression levels of ICC in proximal resection margin(2.10±1.12 vs 6.20±1.89,P<0.01)and the distal resection margin(2.15±1.18 vs 6.25±1.95,P<0.01)of PGS group were statistically significant lower than those in the control group.Conclusion1.The age of patients with distal gastric cancer is closely related to the occurrence of postsurgical gastroparesis,especially for patients more than 65 years old.2.The blood glucose concentration in patients underwent radical resection is closely related to the occurrence of postsurgical gastroparesis,especially for patients with postoperative blood glucose concentration ?8mmol/L.3.The serum albumin concentration in patients with distal gastric cancer is closely related to the occurrence of postsurgical gastroparesis,especially for patients with preoperative albumin concentration <35g/L and postoperative albumin concentration<30g/L.4.The number of ICC in the proximal and distal resection margin of patients with postsurgical gastroparesis was significantly less than that in the control group.