SciCombinator

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Malabsorption syndromes are common in family medicine but may be overlooked because of a wide variation in presentation. Classic symptoms include diarrhea, steatorrhea, weight loss, flatulence, and postprandial abdominal pain. Nongastrointestinal manifestations can include elevated levels of liver function markers, anemia, skin conditions, infertility, and bone disease. Associated conditions include lactose intolerance, celiac disease, and exocrine pancreatic insufficiency. Testing should include screening for anemia. A standard test for lactose intolerance is the hydrogen breath test; however, formal testing typically is not required for diagnosis. The diagnosis of celiac disease depends on serologic testing, histologic findings on duodenal biopsy, or both. Patients should not restrict their diets before testing for malabsorption syndromes. If the initial evaluation is negative for celiac disease, other conditions should be considered, including nonceliac gluten sensitivity, irritable bowel syndrome, and fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs) intolerance. Therapies for patients with malabsorption syndromes involve dietary modification. A lactose-restricted diet and use of dairy substitutes are recommended for lactose intolerance. A gluten-free diet is the primary intervention for celiac disease. Pancreatic enzyme replacement therapy and replacement of fat-soluble vitamins are the primary therapies for management of exocrine pancreatic insufficiency.

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With the development in the past 20 years, minimally invasive gastrointestinal and colorectal surgery is now in its prime of life, with a high level in terms of surgical technique, surgical standardization, innovative technology and technical training. However, in the prime of life, in order to avoid the decline, we must meet new challenges. With the advent of the era of 5G and artificial intelligence, plus a series of changes in the internal and external environment, minimally invasive surgery, and even the entire surgery will have a major impact, including changes in treatment patterns, emphasis of multidisciplinary comprehensive treatment, changes in disease spectrum, and except neoplasms, more benign and functional diseases may require minimally invasive surgery. The gastrointestinal surgery specialist relying on “craft” will likely be replaced by an artificial intelligence surgical system. In the face of challenges, we should not forget our initial intentions, and should diligently reflect on ourselves, keeping the patient-centered minimally invasive treatment concept. Meanwhile, we should go to the basic hospitals to further establish a standardized training system, continue to maintain innovative thinking and keep pace with the times, so that we can grasp the prime of life for minimally invasive gastrointestinal and colorectal surgery.

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Department of minimally invasive gastrointestinal surgery in Peking University Cancer Hospital (also named as Department of Gastrointestinal Surgery IV) was established on April 7, 2009. Up to now, ten years have passed since its foundation. As the first department built in specialized cancer hospital, which mainly focuses on laparoscopic surgery, its foundation and development has a very important historical and practical significance in the development of surgical oncology in China. Reviewing the rapid growth of the Department of Minimally Invasive Gastrointestinal Surgery over the past decade, on the one hand, it has benefited from the opportunities of the times and the support of leaders in Peking University Cancer Hospital at that time. More importantly, the progress owes to the pioneering Professor Su Xiangqian, who is brave and innovative, with indomitable spirit and advanced management philosophy. With rigorous training, the ability of the team has been steadily enhanced, the competitiveness has been gradually improved, and the development direction which focuses on laparoscopic gastric cancer surgery and laparoscopic colorectal cancer surgery has been established. Now, the Department of Minimally Invasive Gastrointestinal Surgery has become a well-known domestic gastrointestinal tumor center. In the past ten years, under the leadership of Professor Su Xiangqian, the growth of this team is innovative and comprehensive: (1) Introduce the internationally advanced Baldrige medical service management framework, and propose the “management by principle” concept to improve the core competitiveness of the department; (2) Establish an academic brand by laparoscopic standardized surgery training courses for gastrointestinal tumors, promote cooperation and exchange at home and abroad, and participate in international multi-center clinical research projects; (3) Adhere to the “formation of a research-oriented department, conducting clinical and basic research simultaneously” as the development direction; (4) Stick to the core development concept of team building and cultivate professional talents. Looking forward to the future, our team will not forget the beginning of the heart, and move forward! In the next ten years, we will break through ourselves and continue to pursue the higher level!

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Whether the transanal total mesorectal resection (taTME) techniques increase the risk of anastomotic failure is inconclusive. This paper discusses the anastomotic problems of taTME from different aspects including anatomical factors and technical characteristics. In terms of the anatomic and physiological characteristics of the lower rectum, the Hiatal ligament and the density of the perirectal space is a disadvantage to the anastomosis of taTME, while the prolapse of the rectum may be a beneficial factor. Due to the unique technical characteristics of taTME, the main reason affecting its anastomosis at present is that the caudal space at the distal end is not sufficiently mobilized, especially for male and lower anastomosis. In addition, stapled anastomosis at the level of anorectal ring may cause more problems, while manual anastomosis at the lower level may bring better results.

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Objective: To explore the feasibility of assessing complications registration through medical information. Methods: A descriptive case series study was performed to retrospectively collect medical information and complication registration information of gastric cancer patients at Department of Gastrointestinal Cancer Center Ward I, Peking University Cancer Hospital from November 1, 2016 to March 1, 2017 (the first period), and from November 1, 2018 to March 1, 2019 (the second period). Case inclusion criteria: (1) adenocarcinoma confirmed by gastroscopy and biopsy; (2) patients undergoing open surgery or laparoscopic radical gastrectomy; (3) complete postoperative medical information and complication information. Patients who were directly transferred to ICU after surgery and underwent emergency surgery were excluded. Because difference of the complication registration procedure at our department existed before and after 2018, so the above two periods were selected to be used for analysis on enrolled patients. The prescription information during hospitalization, including nursing, medication, laboratory examination, transference, surgical advice, etc. were compared with the current Standard Operating Procedure (SOP, including preoperative routine examinations, inspection, perioperative preventive antibiotic use, postoperative observational tests, inspection, routine nutritional support, prophylactic anticoagulation, and prophylactic inhibition of pancreatic enzymes, etc.) for gastric cancer at our department. Medical order beyond SOP was defined as medical order variation. Postoperative complication was diagnosed using the Clavien-Dindo classification criteria, which was divided into I, II, IIIa, IIIb, IVa, IVb, and V. Medical order variation and complication registration information were compared between the two periods, including consistence between medical order variation and complication registration, missing report, underestimation or overestimation of medical order variation, and registration rate of medical order variation [registration rate = (total number of patients-number of missing report patients)/total number of patients], severe complications (Clavien-Dindo classification ≥ III), medical order variation deviating from SOP and the corresponding inferred grading of complication. The data was organized using Microsoft Office Excel 2010. Results: A total of 177 gastric cancer patients were included in the analysis. The first period group and the second period group comprised 89 and 88 cases, respectively. The registrated complication rate was 23.6% (21/89) and 36.4% (32/88), and the incidence of severe complication was 2.2% (2/89) and 4.5% (4/88) in the first and the second period, respectively. The complication rate inferred from medical order variation was 74.2% (66/89) and 78.4% (69/88), and the incidence of severe complication was 7.9% (7/89) and 4.5% (4/88) in the first and second period, respectively. In the first and second period, the proportions of medical order variation in accordance with registered complication were 36.0% and 45.5% respectively; the proportion of underestimation, overestimation and missing report were 5.6% and 4.5%, 4.5% and 4.5%, 53.9% and 45.5%, respectively; the registration rate of medical order variation was 46.1% and 54.5%; the number of case with grade I complications inferred from medical order variation was 34 (38.2%) and 25 (28.4%), respectively; and the number of grade II was 12 (13.5%) and 15 cases (17.0%), respectively. The reason of the missing report of medical order variation corresponding to grade I complication was mainly the single use of analgesic drugs outside SOP, accounting for 76.5% (26/34) and 64.0% (16/25) in the first and second period respectively, and that corresponding to grade II complication was mainly the use of non-prophylactic antibiotics, accounting for 9/12 cases and 5/15 cases, respectively. Conclusions: Medical information can evaluate the morbidity of complication feasibly and effectively. Attention should be paid to routine registration to avoid specific missing report.

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Objective: To identify the risk factors of perioperative complications after radical gastrectomy for gastric cancer. Methods: A retrospective case-control study was performed. Case inclusion criteria: (1) patients undergoing radical gastrectomy (D2); (2) primary gastric cancer without distant organ metastasis confirmed by postoperative pathology; (3) no neoadjuvant chemotherapy before surgery. Patients with peritoneal tumor dissemination found during operation, undergoing palliative operation due to distant metastasis, and undergoing combined organ resection and those without complete clinicopathological data were excluded. According to the above criteria, 426 patients with gastric cancer at our department from January 2015 to June 2017 were included in this study. Of 426 patients, 285 were male and 141 were female with a mean age of (55.4±9.7) years. According to the “Japan Clinical Cancer Research Group (JCOG) classification criteria for postoperative complications of gastric cancer”, patients with grade II and higher complications were classified as complication group, and patients with no complication or grade I complication were classified as non-complication group. Baseline data were compared between two groups. Associations of perioperative complication with gender, age, body mass index, preoperative routine laboratory test, American Society of Anesthesiologists (ASA) classification, activities of daily living (ADL) assessment, past medical history as well as preoperative conditions (hypertension and/or diabetes), surgical resection procedure, incision type, operation time, intraoperative blood loss/body mass ratio were examined. Univariate analysis was performed using χ(2) test and the Wilcoxon rank sum test to screen the statistically significant variables associated with perioperative complications. The significant variables were included in multivariate logistic regression analysis to identify risk factors of perioperative complication. Results: Grade II or higher complications after surgery were developed in 97 patients (22.8%), which included anastomotic leakage in 18 cases (4.2%), postoperative bleeding in 9 cases (2.1%), abdominal abscess in 5 cases (1.2%), intestinal obstruction in 5 cases (1.2%), pancreatic leakage in 1 case (0.2%), and other adverse events in 59 cases (13.8%). Univariate analysis suggested that the gender, age, ADL, incision type, intraoperative blood loss/body mass ratio, and operation time were associated with perioperative complication (all P<0.05). Multivariate analysis revealed that elder age (OR=1.033, 95% CI:1.013-1.053, P=0.013), incision type of laparotomy (OR=2.091, 95% CI:1.247-3.508, P=0.004), longer operation time (OR=1.004, 95% CI:1.001-1.007, P=0.001) and higher ratio of intraoperative blood loss/body mass (OR=1.100, 95% CI: 1.039-1.163, P=0.031) were risk factors for postoperative complications. Conclusion: Attention should be paid to those cases with elder age, laparotomy incision, longer operation time and higher ratio of intraoperative blood loss/body mass, and perioperative management after gastrectomy should be improved.

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Objective: To investigate the morbidity and treatment of early postoperative complications after laparoscopic D2 radical gastrectomy for gastric cancer, and to explore the risk factors. Methods: A case-control study was performed to retrospectively collect clinicopathological data of 764 patients undergoing laparoscopic D2 radical gastrectomy for gastric cancer at our department between January 2015 and December 2017. Patient inclusion criteria: (1) gastric cancer diagnosed by preoperative electronic gastroscopy and biopsy, and confirmed by postoperative pathology; (2) without invasion into adjacent organs by preoperative evaluation of tumors; (3) tumors without definite liver and distant metastasis; (4) R0 resection of gastric cancer and standard D2 lymph node dissection; (5) patients with informed consent. Exclusion criteria: (1) unperformed laparoscopic D2 radical resection; (2) other types of gastric tumor confirmed by pathology; (3) cases with incomplete clinical data. Complication occurring within two weeks after laparoscopic D2 gastrectomy was defined as early postoperative complication. Patients were divided into two groups: non-complication group (693 cases) and complication group (71 cases) according to the occurrence of complications after operation. The clinicopathological data of two groups were analyzed and compared with t test and χ(2) test, and the factors of P < 0.2 were included in the multivariate logistic regression model to analyze the risk factors of postoperative complications. Results: Of 764 patients, 71 (9.3%) developed early postoperative complications, with median onset time of 3 (1 to 11) days. Surgical complications accounted for 7.9% (60/764), including 13 cases (1.7%) of abdominal hemorrhage, 12 cases (1.6%) of anastomotic leakage, 10 cases (1.3%) of incision infection, 8 cases (1.0%) of anastomotic bleeding, 7 cases (0.9%) of gastric stump weakness, 4 cases (0.5%) of abdominal infection, 4 cases (0.5%) of duodenal stump leakage and 2 cases (0.3%) of small intestinal obstruction. Non-surgical complications accounted for 1.4% (11/764), including 6 cases (0.8%) of pulmonary infection and 5 cases (0.7%) of cardiovascular disease. Two cases (0.3%) died of sepsis caused by severe abdominal infection; 9 cases (1.2%) recovered after receiving the second operation, among whom 5 cases were abdominal hemorrhage, 2 cases were anastomotic leakage and 2 cases were duodenal stump leakage; the remaining patients were healed with conservative treatment. Compared with patients without complications, patients with complications had higher proportions of BMI ≥24 kg/m(2) [42.3% (30/71) vs. 24.2%(168/693), χ(2)=10.881, P=0.001], comorbity [64.8% (46/71) vs. 33.5% (232/693), χ(2)=27.277, P<0.001], combined organ resection [70.4% (50/71) vs. 20.5% (142/693), χ(2)=85.338, P<0.001], and pTNM stage of III [70.4% (50/71) vs. 40.1% (278/693), χ(2)=24.196, P<0.001], meanwhile had longer time to postoperative flatus [(4.2±2.1) days vs. (2.9±1.2) days, t=4.621, P=0.023], longer hospital stay [(34.6±12.6) days vs. (14.2±6.2) days, t=9.862, P<0.001] and higher hospitalization cost [(126.8±64.5) thousand yuan vs. (85.2±35.8) thousand yuan, t=11.235, P<0.001]. Multivariate analysis showed that BMI ≥24 kg/m(2) (OR=3.762, 95% CI: 1.960-8.783, P=0.035), accompanying disease (OR=8.620, 95% CI: 1.862-29.752, P<0.001), combined organ resection (OR=6.210, 95% CI: 1.357-21.568, P=0.026), and pTNM stage (OR=4.752, 95% CI: 1.214-12.658, P<0.001) were the independent risk factors of postoperative complications. Conclusions: Laparoscopic D2 radical gastrectomy is a safe and effective approach for gastric cancer. Most early postoperative complications can obtain satisfactory efficacy after conservative treatment. Perioperative management should be strengthened for those patients with high BMI, accompanying diseases, combined organ resection, and advanced pTNM stage.

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Objective: To investigate the risk factors of anastomotic leakage (AL) after laparoscopic surgery in rectal cancer patient with neoadjuvant therapy and construct a nomogram prediction model. Methods: This study was a retrospective case-control study that collected and reviewed the clinicopathological data of 359 patients who underwent laparoscopic surgery from January 2012 to January 2018, including 202 patients from the Department of General Surgery, Nanfang Hospital of Southern Medical University and 157 patients from the Department of Gastrointestinal Surgery of Fujian Provincial Cancer Hospital. Inclusion criteria: (1) age ≥ 18 years old; (2) diagnosis as rectal cancer by biopsy before treatment; (3) distance from tumor to anus within 12 cm; (4) locally advanced stage (T3-T4 or N+) diagnosed by imaging (CT, MRI, PET or ultrasound); (5) standardized neoadjuvant therapy followed by laparoscopic radical operation. Exclusion criteria: (1) previous history of colorectal cancer surgery; (2) short-term or incomplete standardized neoadjuvant therapy; (3) Miles, Hartmann, emergency surgery, palliative resection; (4) conversion to open surgery. Clinicopathological data, including age, gender, body mass index (BMI), preoperative albumin, distance from tumor to anus, operation hospital, American Society of Anesthesiologists score (ASA score), operation time, T stage, N stage, M stage, TNM stage, pathological complete response (pCR) were analyzed with univariate analysis to identify predictors for AL after laparoscopic surgery in rectal cancer patient with neoadjuvant therapy. Then, incorporated predictors of AL, which were screened by multivariate logistic regression, were plotted by the “rms” package in R software to establish a nomogram model. According to the scale of the nomogram of each risk factor, the total score could be obtained by adding each single score, then the corresponding probability of postoperative AL could be acquired. The area under ROC curve (AUC) was used to evaluate the predictive ability of each risk factor and nomogram on model. AUC > 0.75 indicated that the model had good predictive ability. The Bootstrap method (1000 bootstrapping resamples) was applied as internal verification to show the robustness of the model. The discrimination of the nomogram was determined by calculating the average consistency index (C-index) whose rage was 0.5 to 1.0. Higher C-index indicated better consistency with actual risk. The calibration curve was used to assess the calibration of prediction model. The Hosmer-Lemeshow test yielding a non-significant statistic (P>0.05) suggested no departure from the perfect fit. Results: Of 359 cases, 224 were male, 135 were female, 189 were ≥ 55 years old, 98 had a BMI > 24 kg/m(2), 176 had preoperative albumin ≤ 40 g/L, 128 had distance from tumor to anus ≤ 5 cm, 257 were TNM 0-II stage, 102 were TNM III-IV stage, and 84 achieved pCR after neoadjuvant therapy. The incidence of postoperative AL was 9.5% (34/359). Univariate analysis showed that gender, preoperative albumin and distance from tumor to the anus were associated with postoperative AL (All P<0.05). Multivariate logistic regression analysis revealed that male (OR=2.480, 95% CI: 1.012-6.077, P=0.047), preoperative albumin ≤40 g/L (OR=5.319, 95% CI: 2.106-13.433, P<0.001) and distance from tumor to anus ≤ 5 cm (OR=4.339, 95% CI: 1.990-9.458, P<0.001) were significant independent risk factors for postoperative AL. According to these results, a nomogram prediction model was constructed. The male was for 55 points, the preoperative albumin ≤ 40 g/L was for 100 points, and the distance from tumor to the anus ≤ 5 cm was for 88 points. Adding all the points of each risk factor, the corresponding probability of total score would indicated the morbidity of postoperative AL predicted by this nomogram modal. The AUC of the nomogram was 0.792 (95% CI: 0.729-0.856), and the C-index was 0.792 after internal verification. The calibration curve showed that the predictive results were well correlated with the actual results (P=0.562). Conclusions: Male, preoperative albumin ≤ 40 g/L and distance from tumor to the anus ≤ 5 cm are independent risk factors for AL after laparoscopic surgery in rectal cancer patient with neoadjuvant therapy. The nomogram prediction model is helpful to predict the probability of AL after surgery.

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Objective: To evaluate the risk factors of coloanal anastomotic stricture after laparoscopic intersphincteric resection (Lap-ISR) for patients with low rectal cancer. Methods: A retrospective case-control study was performed to collect clinicopathological data from a prospective database (registration number: ChiCTR-ONC-15007506) at the Department of Colorectal Surgery, the Characteristic Medical center of PLA Rocket Force. From June 2011 to August 2018, a total of 144 consecutive patients with low rectal cancer who underwent Lap-ISR were enrolled in the study. Inclusion criteria: (1) reconstruction of digestive tract by end-to-end hand-made coloanal anastomosis (HCAA); (2) distance from lower tumor margin to anorected sphincter ring < 1 cm and distance from lower tumor margin to intersphincteric groove ≥ 1 cm; (3) T1-3 stage tumor with expected negative circumferential resection margin evaluated by preoperative MRI or 3D endoanal ultrasound; (4) rectal cancer confirmed as well- or moderately-differentiated adenocarcinoma; (5) preoperative Wexner incontinence score >10 points. Exclusion criteria: (1) follow-up period less than 3 months; (2) multiple primary cancers; (3) undergoing colonic J-pouch, coloplasty or reconstruction of end-to-side coloanal anastomosis; (4) death within perioperative period (within 3 months after surgery). Coloanal anastomotic stricture was diagnosed if the index finger or 12 mm electronic colonoscope had obvious resistance through the anastomosis or new rectum, or could not pass, accompanied by clinical symptoms such as difficult defecation and anal incontinence. Degree of anastomotic stricture was divided into 3 grades: grade A required anal enlargement, laxative or enema to assist defecation without active surgical treatment; grade B required surgery or endoscopic intervention; grade C required definitive ostomy, including unreducible preventive ileostomy or permanent colostomy. Univariate and multivariate analysis were used to evaluate the effects of 28 variables, including baseline data (age, gender, body mass index, neoadjuvant therapy, etc.), tumor-related factors (distance between tumor low margin and anal edge, maximum diameter of tumor, TNM staging, etc.), surgery-related factors (operation time, intraoperative blood loss, ISR procedure, anastomotic height, etc.) and anastomotic leakage, on the postoperative coloanal anastomotic stricture. Univariate analysis used χ(2) test or Fisher’s exact test, then factors with P<0.05 were further included in multivariate analysis using logistic regression. Results: A total of 144 patients were enrolled in the study, including 90 males and 54 females with a median age of 59 years and median BMI of 24.88 kg/m(2). R0 resection rate was 96.5% (139/144). Median tumor distal resection margin was 1.5 (0.5 to 3.0) cm. Median follow-up was 31.5 (4 to 86) months. Coloanal anastomotic stricture was observed in 19 patients (13.2%), including 3 cases (2.1%) of grade A, 9 cases (6.2%) of grade B, and 7 cases (4.9%) of grade C. The median interval from the initial surgery to diagnosis of anastomotic stricture was 7 (1 to 31) months. Univariate analysis showed that male (χ(2)=6.795, P=0.009), radiotherapy (χ(2)=13.330, P=0.001), operation type of ISR (χ(2)=7.996, P=0.013), and anastomotic leakage (χ(2)=10.198, P=0.004) were associated with the postoperative coloanal anastomotic stricture. Multivariate analysis further indicated that male (OR=5.975, 95% CI: 1.209-29.534, P=0.028), postoperative radiotherapy (OR=8.748, 95% CI: 2.397-31.929, P=0.001), and anastomotic leakage (OR=6.313, 95% CI: 1.834-21.734, P=0.003) were independent risk factor of postoperative coloanal anastomotic stricture. Conclusion: For male patients, or patients with postoperative radiotherapy or anastomotic leakage, close follow-up should be carried out to prevent postoperative coloanal anastomotic stricture following Lap-ISR.

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Objective: To evaluate the efficacy of reinforcement on duodenal stump using single purse-string suture during laparoscopic radical gastrectomy for gastric cancer in preventing duodenal stump leakage. Methods: A descriptive cohort study was conducted to retrospectively collect clinical data of 211 patients with gastric adenocarcinoma who underwent laparoscopic radical gastrectomy with Roux-en-Y or Billroth Ⅱ reconstruction and reinforcement on duodenal stump using laparoscopic single purse-string suture in Zhongshan Hospital of Fudan University between January 2013 and December 2016. Of 211 patients, 136 were male and 75 were female with mean age of (57.5±11.1)(24 to 87) years. Tumors locating at gastric upper 1/3, middle 1/3 and low 1/3 were found in 62, 68 and 81 patients respectively. Eighty-three cases underwent total gastrectomy, 128 underwent distal subtotal gastrectomy, 107 underwent Roux-en-Y reconstruction and 104 underwent Billroth II reconstruction. The procedure of reinforcement on duodenal stump using single purse-string suture during laparoscopic radical gastrectomy was as follows: (1) after cutting the duodenal stump to about 2.0 cm in length, use a 3-0 single-strand absorbable suture to make a muscle layer purse at a distance of 1.0 to 1.5 cm from the duodenal stump; (2) use the purse line to make a slipknot; (3) push the duodenum stump into the purse with a needle holder or grasper; (4) tighten the knot of the purse string, and then make 4 to 5 knots for reinforcement. Postoperative complications were defined and graded according to the Clavien-Dindo grading criteria, and the incidence of early complications was recorded. Clinicopathologic features and postoperative outcomes were analyzed. Results: All patients completed operations successfully. The mean time of laparoscopic single purse-string suture was (5.1±1.6) (3.6 to 10.2) minutes. Postoperative early complication occurred in 31 cases (14.7%), of whom 27 cases developed surgery-related complications (12.8%), including 7 cases (3.3%) of peritoneal infection, 6 (2.8%) of pancreatic leakage, 4 (1.9%) of wound infection, 4 (1.9%) of gastroplegia, 2 (0.9%) of peritoneal hemorrhage, 2 (0.9%) of intestinal obstruction, 2 (0.9%) of lymphatic leakage, and no duodenal stump leakage; while 4 cases (1.9%) developed internal non-surgical complication, including 3 cases (1.4%) of pulmonary infection and 1 (0.5%) of cardiovascular event. The patient with peritoneal hemorrhage was healed after re-operation and all other patients were discharged uneventfully after conservative treatment. Four cases (1.9%) developed complications beyond grade III a of Clavien-Dindo criteria. Conclusion: Reinforcement on duodenal stump using laparoscopic single purse-string suture during laparoscopic radical gastrectomy with Roux-en-Y or Billroth II reconstruction is simple and effective, and can prevent the risk of development of duodenal stump leakage.