Objective:To investigate the effect of ligation methods of inferior mesenteric artery (IMA) on preserving left colic artery (LCA) in laparoscopic radical resection of rectal cancer.Methods:The prospective randomized controlled study was conducted. The clinical data of 864 patients who underwent laparoscopic radical resection of rectal cancer at Renji Hospital of Shanghai Jiaotong University School of Medicine from January 2020 to December 2024 were selected. Patients were randomly divided into the low ligation group and high ligation group using a random number table. Patients of the low ligation group underwent laparoscopic radical resection of rectal cancer with preserving LCA by low ligation of IMA and apical lymph node dissection, and patients of the high ligation group underwent laparoscopic radical resection of rectal cancer with traditional high ligation of IMA. Observation indicators: (1) grouping of the enrolled patients; (2) intraoperative conditions; (3) postoperative pathological examination; (4) postoperative recovery. Comparison of measurement data with normal distribution between groups was conducted using the independent sample t test. Comparison of count data between groups was conducted using the chi-square test or Fisher exact probability. Comparison of ordinal data between groups was conducted using the non-parametric test. Results:(1) Grouping of the enrolled patients. A total of 864 patients with rectal cancer who underwent laparoscopic radical resection of rectal cancer were screened for eligibility, including 410 males and 454 females, aged (63±11)years. All 864 patients were randomly divided into the low ligation group and high ligation group, with 432 patients in each group. There was no significant difference in gender, age, body mass index, carcinoembryonic antigen, distance from tumor to anal margin, diabetes, hypertension, neoadjuvant radiochemotherapy, IMA subtypes and IMA length between the two groups ( P>0.05), ensuring comparability. (2) Intraoperative conditions. All patients of the two groups successfully completed surgery, with no errors in blood vessel ligation during operation or conversion to open surgery. There was a significant difference in time of IMA dissection between the low ligation group and high ligation group [(31±11)minutes vs. (28±9)minutes, t=4.39, P<0.05], and there was no significant difference in total operation time, volume of intra-operative blood loss or prophylactic stoma rate between the two groups ( P>0.05). (3) Postopera-tive pathological examination. There was a significant difference in the number of lymph node dissected between the low ligation group and high ligation group (1.8±1.4 vs. 1.5±1.4, t=2.51, P<0.05), and there was no significant difference in tumor diameter, the total number of lymph node dissected, total lymph node positive status, No.253 lymph node positive status, TNM staging between the two groups ( P>0.05). (4) Postoperative recovery. The time to postoperative first flatus and the number of anastomotic leakage of patients in the low ligation group were (74±22)hours and 16 cases, versus (78±20)hours and 31 cases in the high ligation group, respectively, showing significant differences in the above indicators between the two groups ( t=2.52, χ2=5.06, P<0.05). There was no significant difference in the time to postoperative initial liquid food intake, duration of post-operative hospital stay, duration of abdominal drainage tube indwelling, duration of anal tube indwelling, postoperative wound infection, pulmonary infection, intestinal obstruction, or urinary dysfunction between the two groups ( P>0.05). None of patients in the two groups had readmission or death during the postoperative 30 days. Conclusion:Low ligation of IMA in laparoscopic radical resection of rectal cancer can guide precise LCA preservation, which is beneficial for accelerating the recovery of intestinal function and reducing the incidence of anastomotic leakage.

Objective To investigate the risk factors for lymph node metastasis in resectable lung adenocarcinoma by combining spatial location, clinical, and imaging features, and to construct a lymph node metastasis prediction model. Methods A retrospective study on patients who underwent chest CT at the First Affiliated Hospital of Nanjing Medical University from June 2016 to June 2020 and were surgically confirmed to have invasive lung adenocarcinoma with or without lymph node metastasis was conducted. Patients were divided into a positive group and a negative group based on the presence or absence of lymph node metastasis. Clinical and imaging data of the patients were collected, and the independent risk factors for lymph node metastasis in resectable lung adenocarcinoma were analyzed using univariate and multivariate logistic regression. A combined spatial location-clinical-imaging feature prediction model for lymph node metastasis was established and compared with the traditional lymph node metastasis prediction model that does not include spatial location features. Results A total of 611 patients were included, with 333 in the positive group, including 172 males and 161 females, with an average age of (58.9±9.7) years; and 278 in the negative group, including 127 males and 151 females, with an average age of (60.1±11.4) years. Univariate and multivariate logistic regression analyses showed that the spatial relationship of the lesion to the lung hilum, nodule type, pleural changes, and serum carcinoembryonic antigen (CEA) levels were independent risk factors for lymph node metastasis. Based on this, the combined spatial location-clinical-imaging feature prediction model had a sensitivity of 91.67%, specificity of 74.05%, accuracy of 87.88%, and area under the curve (AUC) of 0.885. The traditional lymph node metastasis prediction model, which did not include spatial location features, had a sensitivity of 76.40%, specificity of 72.10%, accuracy of 53.86%, and AUC of 0.827. The difference in AUC between the two prediction methods was statistically significant (P=0.026). Compared with the traditional prediction model, the predictive performance of the combined spatial location-clinical-imaging feature prediction model was significantly improved. Conclusion In patients with resectable lung adenocarcinoma, those with central/inner spatial location, solid density, pleural changes with wide base depression, and elevated serum CEA levels have a higher risk of lymph node metastasis.

Objective:To compare postoperative anal function recovery between laparoscopic subtotal colectomy with antiperistaltic cecorectal anastomosis and laparoscopic total colectomy with ileorectal anastomosis for slow transit constipation.Methods:This multicenter retrospective cohort study enrolled patients meeting the following criteria: (1) severe constipation symptoms (<2 bowel movements/week), absent or insignificant defecation urge, abdominal distension, requiring laxatives to maintain bowel movements or laxatives being ineffective; (2) constipation symptoms for over 5 years, ineffective after >2 years of medical treatment, with strong desire for surgery; (3) significantly prolonged colon transit time (>72 hours) without significant gastric or small intestinal transit dysfunction; (4) no organic colonic lesions confirmed by colonoscopy and abdominal CT. Exclusion criteria: (1) patients undergoing open surgery; (2) exclusion of outlet obstruction constipation (e.g., rectocele, rectal prolapse, puborectalis spasm) by functional defecation MRI; (3) comorbid psychiatric disorders; (4) missing clinical data or loss to follow-up (postoperative follow-up <24 months). Based on these criteria, clinical and follow-up data were collected from 220 patients who underwent either laparoscopic subtotal colectomy with antiperistaltic cecorectal anastomosis (LSC group, n = 115) or laparoscopic total colectomy with ileorectal anastomosis (LTC group, n = 105) for slow transit constipation between January 2013 and December 2022. Subjective anal function (Constipation Severity Score and Wexner Fecal Incontinence Score) and objective anal function (positive rate of rectoanal inhibitory reflex [RAIR] and anorectal manometry) were observed preoperatively and at 6, 12, and 24 months postoperatively. Results:No significant differences were found in baseline characteristics between the two groups (all P >0.05). All surgeries were completed successfully without major significant complications. Subjective anal function assessment: At 24 months postoperatively, Constipation Severity Scores decreased significantly compared to preoperative scores in both groups [LSC group: (25.2±2.8) vs. (2.9±1.8), P <0.001; LTC group: (25.8±2.9) vs. (2.8±1.9), P<0.001]. No significant differences were found between the groups at 6, 12, and 24 months postoperatively (all P>0.05). Wexner Fecal Incontinence Scores at 24 months were significantly lower than those at 6 months in both groups [LSC group: (12.9±1.8) vs. (3.9±2.5), P<0.001; LTC group: (12.6±1.8) vs. (5.4±2.4), P<0.001]. Although no significant difference was found at 6 months ( P = 0.190), the LSC group had significantly lower Wexner scores than the LTC group at 12 and 24 months postoperatively (both P < 0.001). Objective anal function assessment: (1) Positive RAIR rate: Preoperative positive RAIR rates were 33.0% (38/115) in the LSC group and 25.7% (27/105) in the LTC group ( P > 0.05). At 24 months, positive rates increased significantly in both groups [LSC: 66.1% (76/115); LTC: 63.8% (67/105)] compared to preoperative rates (both P<0.001), but no significant differences were found between groups at 6, 12, and 24 months (all P>0.05). (2) Resting pressure (RP) and squeeze pressure (SP): No significant differences were found in preoperative RP and SP between groups (all P>0.05). The LSC group had significantly higher RP and SP than the LTC group at 6 and 12 months postoperatively (all P<0.05), but no significant differences were found at 24 months ( P>0.05). Conclusion:Both laparoscopic subtotal colectomy with antiperistaltic cecorectal anastomosis and laparoscopic total colectomy with ileorectal anastomosis are safe for patients with slow transit constipation. However, laparoscopic subtotal colectomy with antiperistaltic cecorectal anastomosis offers superior postoperative anal function recovery.

Objective:To investigate the effect of ligation methods of inferior mesenteric artery (IMA) on preserving left colic artery (LCA) in laparoscopic radical resection of rectal cancer.Methods:The prospective randomized controlled study was conducted. The clinical data of 864 patients who underwent laparoscopic radical resection of rectal cancer at Renji Hospital of Shanghai Jiaotong University School of Medicine from January 2020 to December 2024 were selected. Patients were randomly divided into the low ligation group and high ligation group using a random number table. Patients of the low ligation group underwent laparoscopic radical resection of rectal cancer with preserving LCA by low ligation of IMA and apical lymph node dissection, and patients of the high ligation group underwent laparoscopic radical resection of rectal cancer with traditional high ligation of IMA. Observation indicators: (1) grouping of the enrolled patients; (2) intraoperative conditions; (3) postoperative pathological examination; (4) postoperative recovery. Comparison of measurement data with normal distribution between groups was conducted using the independent sample t test. Comparison of count data between groups was conducted using the chi-square test or Fisher exact probability. Comparison of ordinal data between groups was conducted using the non-parametric test. Results:(1) Grouping of the enrolled patients. A total of 864 patients with rectal cancer who underwent laparoscopic radical resection of rectal cancer were screened for eligibility, including 410 males and 454 females, aged (63±11)years. All 864 patients were randomly divided into the low ligation group and high ligation group, with 432 patients in each group. There was no significant difference in gender, age, body mass index, carcinoembryonic antigen, distance from tumor to anal margin, diabetes, hypertension, neoadjuvant radiochemotherapy, IMA subtypes and IMA length between the two groups ( P>0.05), ensuring comparability. (2) Intraoperative conditions. All patients of the two groups successfully completed surgery, with no errors in blood vessel ligation during operation or conversion to open surgery. There was a significant difference in time of IMA dissection between the low ligation group and high ligation group [(31±11)minutes vs. (28±9)minutes, t=4.39, P<0.05], and there was no significant difference in total operation time, volume of intra-operative blood loss or prophylactic stoma rate between the two groups ( P>0.05). (3) Postopera-tive pathological examination. There was a significant difference in the number of lymph node dissected between the low ligation group and high ligation group (1.8±1.4 vs. 1.5±1.4, t=2.51, P<0.05), and there was no significant difference in tumor diameter, the total number of lymph node dissected, total lymph node positive status, No.253 lymph node positive status, TNM staging between the two groups ( P>0.05). (4) Postoperative recovery. The time to postoperative first flatus and the number of anastomotic leakage of patients in the low ligation group were (74±22)hours and 16 cases, versus (78±20)hours and 31 cases in the high ligation group, respectively, showing significant differences in the above indicators between the two groups ( t=2.52, χ2=5.06, P<0.05). There was no significant difference in the time to postoperative initial liquid food intake, duration of post-operative hospital stay, duration of abdominal drainage tube indwelling, duration of anal tube indwelling, postoperative wound infection, pulmonary infection, intestinal obstruction, or urinary dysfunction between the two groups ( P>0.05). None of patients in the two groups had readmission or death during the postoperative 30 days. Conclusion:Low ligation of IMA in laparoscopic radical resection of rectal cancer can guide precise LCA preservation, which is beneficial for accelerating the recovery of intestinal function and reducing the incidence of anastomotic leakage.

Objective:To compare postoperative anal function recovery between laparoscopic subtotal colectomy with antiperistaltic cecorectal anastomosis and laparoscopic total colectomy with ileorectal anastomosis for slow transit constipation.Methods:This multicenter retrospective cohort study enrolled patients meeting the following criteria: (1) severe constipation symptoms (<2 bowel movements/week), absent or insignificant defecation urge, abdominal distension, requiring laxatives to maintain bowel movements or laxatives being ineffective; (2) constipation symptoms for over 5 years, ineffective after >2 years of medical treatment, with strong desire for surgery; (3) significantly prolonged colon transit time (>72 hours) without significant gastric or small intestinal transit dysfunction; (4) no organic colonic lesions confirmed by colonoscopy and abdominal CT. Exclusion criteria: (1) patients undergoing open surgery; (2) exclusion of outlet obstruction constipation (e.g., rectocele, rectal prolapse, puborectalis spasm) by functional defecation MRI; (3) comorbid psychiatric disorders; (4) missing clinical data or loss to follow-up (postoperative follow-up <24 months). Based on these criteria, clinical and follow-up data were collected from 220 patients who underwent either laparoscopic subtotal colectomy with antiperistaltic cecorectal anastomosis (LSC group, n = 115) or laparoscopic total colectomy with ileorectal anastomosis (LTC group, n = 105) for slow transit constipation between January 2013 and December 2022. Subjective anal function (Constipation Severity Score and Wexner Fecal Incontinence Score) and objective anal function (positive rate of rectoanal inhibitory reflex [RAIR] and anorectal manometry) were observed preoperatively and at 6, 12, and 24 months postoperatively. Results:No significant differences were found in baseline characteristics between the two groups (all P >0.05). All surgeries were completed successfully without major significant complications. Subjective anal function assessment: At 24 months postoperatively, Constipation Severity Scores decreased significantly compared to preoperative scores in both groups [LSC group: (25.2±2.8) vs. (2.9±1.8), P <0.001; LTC group: (25.8±2.9) vs. (2.8±1.9), P<0.001]. No significant differences were found between the groups at 6, 12, and 24 months postoperatively (all P>0.05). Wexner Fecal Incontinence Scores at 24 months were significantly lower than those at 6 months in both groups [LSC group: (12.9±1.8) vs. (3.9±2.5), P<0.001; LTC group: (12.6±1.8) vs. (5.4±2.4), P<0.001]. Although no significant difference was found at 6 months ( P = 0.190), the LSC group had significantly lower Wexner scores than the LTC group at 12 and 24 months postoperatively (both P < 0.001). Objective anal function assessment: (1) Positive RAIR rate: Preoperative positive RAIR rates were 33.0% (38/115) in the LSC group and 25.7% (27/105) in the LTC group ( P > 0.05). At 24 months, positive rates increased significantly in both groups [LSC: 66.1% (76/115); LTC: 63.8% (67/105)] compared to preoperative rates (both P<0.001), but no significant differences were found between groups at 6, 12, and 24 months (all P>0.05). (2) Resting pressure (RP) and squeeze pressure (SP): No significant differences were found in preoperative RP and SP between groups (all P>0.05). The LSC group had significantly higher RP and SP than the LTC group at 6 and 12 months postoperatively (all P<0.05), but no significant differences were found at 24 months ( P>0.05). Conclusion:Both laparoscopic subtotal colectomy with antiperistaltic cecorectal anastomosis and laparoscopic total colectomy with ileorectal anastomosis are safe for patients with slow transit constipation. However, laparoscopic subtotal colectomy with antiperistaltic cecorectal anastomosis offers superior postoperative anal function recovery.

Objective:To analyze the genetic and molecular characteristics of H9N2 subtype avian influenza viruses from external environment and humans in Anhui Province from 2013 to 2022.Methods:Environmental samples and human samples were collected from Anhui influenza surveillance network laboratory. Sixty-three strains of virus were isolated in chicken embryos. RT-PCR was used to amplify the virus and whole genome sequencing was performed. To construct gene evolutionary tree and analyze its genetic characteristics and potential glycosylation sites.Results:The hemagglutinin (HA) gene belongs to the 9.2.4.5 clade, and the protein cleavage sites are mostly " PSRSSR\GL". The neuraminidase (NA) gene, basic protein-1(PB1) gene, acidic protein (PA) gene, non-structural protein (NS) gene and nucleoprotein (NP) gene belong to the F/98 clade, the matrix protein (MP) gene belongs to the G1/97 clade, and the basic protein-2 (PB2) gene belongs to the ST/7488 clade. Mutations of T155N, R164Q, H183N, T189D/V, A190V/T and Q226L occurred in HA protein, deletion of NA protein occurred at 62-64 sites, and mutations of T271A, I292V/M and E627V/L occurred in PB2 protein. At the same time, mutations of K356R and S409N occurred in the PA protein.Conclusions:The H9N2 subtype avian influenza viruses collected from external environment and human sources in Anhui province from 2013 to 2022 belong to the same evolutionary branch, and amino acid site mutations suggest that the virus shows a tendency to gradually adapt to the mammalian host environment. Therefore, further studies on the adaptive evolution of the virus and related monitoring work are needed.

Objective:Analysis of the characteristics of influenza epidemic in Anhui Province and quantification of the impact of different factors on influenza occurrence, providing scientific basis for better influenza prevention and control.Methods:Descriptive analysis and factor analysis were conducted on influenza-like illness (ILI) cases and RT-PCR results in Anhui Province from 2013 to 2021 using data from China's Influenza Monitoring Information System.Results:The percentage of influenza-like illness (ILI%) of sentinel hospitals in Anhui Province from April 1, 2013 to March 31, 2021 was 3.80% (1 209 142/31 779 987), showing an overall increasing trend, with a relatively high proportion in 2017-2018 at 4.30% (191 148/4 448 211). The proportion of ILI cases in infants and young children aged 0-4 years was a relatively high at 54.14% (654 676/1 209 142), and the highest ILI% was observed in Fuyang City, Anhui Province (6.25%, 236 863/3 788 863). Laboratory monitoring results showed that the positive rate of ILI cases in sentinel hospitals in 8 influenza monitoring years was 16.38% (34 868/212 912), showing an increasing trend year by year, with a relatively proportion in 2017-2018 at 26.19% (6 936/26 488). The detection rate of school-age children aged 5-14 years was a relativelyhigh at 28.81% (13 869/48 144), and the positive rate was a relatively high in Wuhu City among the 16 cities, reaching 22.01% (2 693/122 237). Influenza activity showed a single peak in winter-spring and alternating double peaks in winter-spring and summer, with different subtypes alternating, and A (H3N2) was the dominant subtype in summer. The results of a multiple logistic regression model showed that the positive rate was higher in 2017-2018, among children aged 5-14 years, in winter, and in southern Anhui.Conclusions:Influenza epidemic in Anhui Province has a clear seasonal pattern, and the ILI% and detection rate have shown an upward trend from 2013 to 2021. Therefore, it is suggested to ensure vaccine supply before the winter-spring influenza season arrives, and to strengthen vaccine uptake and health education to avoid the risk of infection during the peak period of influenza.

Objective:To compare the differences between suspension and adherent cells of MDCK cell line in the isolation of influenza virus, and to explore the application prospects of MDCK cell suspension.Methods:Determination of viable cell density and cell specific growth rate were recorded by cell count. The WHO recommended vaccine strains were used for virus infection experiments. After five passages, hemagglutination titers were detected, while the sequencing analysis of their HA and NA genes revealed the mutation frequency.Results:The 24-hour and 48-hour viable cell density of the cell suspension was more stable than that of adherent cells. The cell suspension achieved an HA titer of 1∶256 or higher in the third generation, while adherent cells had no titer. In the fourth and fifth generations, one amino acid site mutation was found in the HA gene of H3N2 and BV subtypes of influenza virus cultured in the cell suspension, while no gene mutation was found in adherent cells in two passages. There were no mutations in the whole NA gene.Conclusions:Suspension of MDCK cells have more stable growth and higher efficiency in virus isolation than adherent cells, meanwhile there was a low rate of virus mutation during continuous passage. This study demonstrated the feasibility of this suspension of MDCK cells for influenza vaccine production based on cell culture technology.

Objective To investigate the effect of indocyanine green(ICG) fluorescence imaging to indicate blood supply of sigmoid-rectal anastomosis in laparoscopic anterior resection of rectal cancer. Methods Here a retrospective cohort study including 175 consecutive patients with rectal cancer scheduled for laparoscopic surgery in Department of Gastrointestinal Surgery of Renji Hospital between January 2019 and December 2022 was analysed. These patients were classified into two groups, according to using ICG or not within surgery: the ICG group (n=65) and the control group (n=110). Operation situations and complications were compared between the two groups. Results The operation time of ICG group was longer than that of control group [(151.6±4.8) min vs (139.5±3.7) min, P=0.04], and the preventive ileostomy rate was lower than that of control group (12.3% vs 34.6%, P=0.01), while the other operation data (intraoperative blood loss, number of lymph node dissection), were similar between the two groups (P>0.05). The rate of anastomotic leakage in ICG group were lower than that in control group (4.6% vs 14.6%, P=0.04), and there was no significant differences in wound infection, urinary retention and intestinal obstruction between the two groups (P>0.05). Conclusions The ICG displays that the blood supply in laparoscopic anterior resection of rectal cancer can reduce the incidence of anastomotic leakage, which improves the surgical safety and the quality of postoperative life.

Objective:To investigate the risk factors for anastomotic leakage after laparo-scopic lower anterior resection (LAR) of rectal cancer, and the application value of its risk assess-ment scoring model.Methods:The retrospective case-control study was conducted. The clinico-pathological data of 539 patients who underwent laparoscopic LAR of rectal cancer in 13 medical centers, including 248 cases in Renji Hospital of Shanghai Jiaotong University School of Medicine, 35 cases in Ningbo First Hospital, 35 cases in Changzhou Second People's Hospital, 32 cases in the First People's Hospital of Nantong, 32 cases in Linyi People's Hospital, 31 cases in Changzhou Wujin People's Hospital, 28 cases in Jiading District Hospital of Traditional Chinese Medicine, 27 cases in the First Hospital of Taizhou, 26 cases in Shanghai Pudong Gongli Hospital, 21 cases in the People's Hospital of Rugao, 11 cases in Central Hospital of Fengxian District, 7 cases in Ningbo Hangzhou Bay Hospital and 6 cases in Jiangsu jianhu People's Hospital, from January 2016 to November 2020 were collected. There were 157 males and 382 females, aged (62.7±0.5)years. Observation indicators: (1) follow-up; (2) risk factors for anastomotic leakage after laparoscopic LAR; (3) establishment of risk assessment scoring model for anastomotic leakage after laparoscopic LAR. Follow-up was conducted by outpatient examination or telephone interview. Patients were followed up at 1 week after discharge or 1 month after the operation to detect the anastomotic leakage. Measurement data with normal distribution were represented as Mean± SD, and measurement data with skewed distribution were represented as M(range). Count data were represented as absolute numbers or percentages, and comparison between groups was analyzed using the chi-square test. Univariate analysis was conducted using the chi-square test and multivariate analysis was conducted usong the Logistic regression model. The area under curve of receiver operating characteristic curve was used to estimate the efficiency of detecton methods. The maximum value of the Youden index was defined as the best cut-off value. Results:(1) Follow-up: 539 patients were followed up at postoperative 1 week and 1 month. During the follow-up, 79 patient had anastomotic leakage, with an incidence of 14.66%(79/539). Of the 79 patients, 39 cases were cured after conservative treatment, 40 cases were cured after reoperation (ileostomy or colostomy). (2) Risk factors for anastomotic leakage after laparoscopic LAR. Results of univariate analysis showed that sex, age, body mass index, smoking and/or drinking, tumor diameter, diabetes mellitus, hemoglobin, albumin, grade of American Society of Anesthesio-logists (ASA), neoadjuvant chemoradiotherapy, distance from anastomotic level to dentate line, the number of pelvic stapler, reinforced anastomosis, volume of intraoperative blood loss, placement of decompression tube, preservation of left colic artery, operation time and professional doctors were related factors for anastomotic leakage after laparoscopic LAR ( χ2=14.060, 4.387, 5.039, 4.094, 17.488, 33.485, 25.066, 28.959, 34.973, 34.207, 22.076, 13.208, 16.440, 17.708, 17.260, 4.573, 5.919, 5.389, P<0.05). Results of multivariate analysis showed that male, tumor diameter ≥3.5 cm, diabetes mellitus, hemoglobin <90 g/L, albumin <30 g/L, grade of ASA ≥Ⅲ, neoadjuvant chemoradiotherapy, distance from anastomotic level to dentate line <1 cm, the number of pelvic stapler ≥3, non-reinforced anastomosis, volume of intraoperative blood loss ≥100 mL and no placement of decom-pression tube were independent risk factors for anastomotic leakage after laparoscopic LAR ( odds ratio=2.864,3.043,12.556,7.178,8.425,12.895,8.987,4.002,3.084,4.393,3.266,3.224,95% confidence interval as 1.279?6.411, 1.404?6.594, 4.469?35.274, 2.648?19.459, 2.471?28.733, 4.027?41.289, 3.702?21.777, 1.746?9.171, 1.365?6.966, 1.914?10.083, 1.434?7.441, 1.321?7.867, P<0.05). (3) Establishment of risk assessment scoring model for anastomotic leakage after laparoscopic LAR. based on the results of univariate analysis, clinicopathological factors with χ2>20, χ2>10 and ≤20 or χ2≤10 were defined as scoring of 3, 2, 1, respectively. The cumulative clinicopatho-logical factors scoring ≥6 was defined as an effective evaluating indicator for postoperative anastomotic leakage. The risk assessment scoring model (6-321) for anastomotic leakage after laparoscopic LAR was established. The cumulative value ≥6 indicated high incidence of anastomotic leakage, and the cumulative value <6 indicated low incidence of anastomotic leakage. Conclusions:Male, tumor diameter ≥3.5 cm, diabetes mellitus, hemoglobin <90 g/L, albumin <30 g/L, grade of ASA ≥Ⅲ, neo-adjuvant chemoradiotherapy, distance from anastomotic level to dentate line <1 cm, the number of pelvic stapler ≥3, non-reinforced anastomosis, volume of intraoperative blood loss ≥100 mL and no placement of decompression tube are independent risk factors for anastomotic leakage after laparoscopic LAR. The risk assessment scoring model (6-321) is established according to the above results.The cumulative value ≥6 indicates high incidence of anastomotic leakage and the cumulative value <6 indicates low incidence of anastomotic leakage.