Objective:To investigate the value of surgical classification and pelvic floor reconstruction in pelvic exenteration for locally recurrent or locally advanced rectal cancer. Methods:A retrospective descriptive study method was used.Perioperative data were collected from 67 consecutive patients with locally advanced or locally recurrent rectal cancer who underwent pelvic exenteration at the Department of Anorectal Surgery,the Second Affiliated Hospital of Navy Military Medical University between November 2021 and November 2022 through the Chinese Combined Pelvic Exenteration Case Database for rectal cancer.The surgical range was divided into two categories:mainly localized in the pelvic cavity(48 cases)and combined with resection of the main tissue of the pelvic wall(1 9 cases).Outcome indexes included:(1)preoperative general data of patients;(2)intraoperative conditions;(3)postoperative recovery and complications(postoperative complications were evaluated by international Clavien-Dindo classification);(4)follow-up(outpatient and telephone follow-up were used to understand the postoperative survival,tumor recurrence and metastasis of patients,and the follow-up time was up to February 28,2023 or the case died).Measurement data are expressed by median(range),and enumeration data are expressed by example(％). Results:In the pelvic resection group,the median age of 48 patients was 57.5 years(range:31-82 years);29 were males and 19 were females;26 of them had locally advanced rectal cancer and 22 had locally recurrent rectal cancer;39 had a history of chemotherapy,immunotherapy or targeted therapy,and 26 had a history of radiotherapy;the median operation time was 425 min(range:240-1 020 min);the median intraoperative blood loss was 500 mL(range:200-4 000 mL);the median time to recovery of intestinal function was 3 d(range:1-9 d);the median recovery time of empty pelvis syndrome was 25.3 d(range:5-105 d);43 patients had postoperative complications＜grade Ⅲ,and of the 5 patients with ≥ grade Ⅲcomplications,2 died of multiple organ failure 7 d after operation,2 patients had surgical hemostasis for massive hemorrhage of pelvic floor wounds after operation,and 1 patient recovered from postoperative respiratory failure after rescue.In the combined pelvic wall resection group,the median age of 1 9 patients was 54.5 years(range:43-76 years);9 were males and 10 were females;4 patients had locally advanced rectal cancer and 15 patients had locally recurrent rectal cancer,all of whom had a history of chemotherapy,immunotherapy or targeted therapy,and 1 5 patients had a history of radiotherapy;the median operation time was 580 min(range:360-960 min);the median intraoperative blood loss was 1 600 mL(range:400-4 000 mL);the median intestinal function recovery time was 3 d(range:2-7 d);the median empty pelvis syndrome recovery time was 62.3 d(range:7-120 d);15 patients had postoperative complications＜grade Ⅲ,and of the 4 patients with grade ≥ Ⅲ,3 patients had surgical hemostatis for postoperative pelvic floor wound bleeding and 1 patient recovered after the second operation for intestinal obstruction.As of February 28,2023 or death,67 patients were followed up for a median of 7.5 months(range:3-1 5 months),and 3 patients died 3-8 months after operation due to rapid tumor progression,severe urinary tract infection,and sudden heart disease during the follow-up period.The remaining 62 cases survived. Conclusion:The surgical classification has guiding significance for preoperative surgical planning in patients with locally advanced or locally recurrent rectal cancer who undergo combined pelvic exenteration,and the method of pelvic floor reconstruction based on biological mesh is safe and feasible in combined pelvic exenteration for locally advanced or locally recurrent rectal cancer.

Objective:To investigate the influencing factors of anastomotic leakage after laparoscopic intersphincter resection (ISR) for extremely low rectal cancer and construction of nomogram prediction model.Methods:The retrospective case-control study was conducted. The clinicopathological data of 812 patients who underwent laparoscopic ISR for extremely low rectal cancer in the Second Affiliated Hospital of Naval Medical University (Shanghai Changzheng Hospital) from February 2012 to February 2022 were collected. There were 459 males and 353 females, aged (51±11)years. Observation indicators: (1) surgical situations; (2) follow-up; (3) influencing factors of postoperative anastomotic leakage; (4) construction and evaluation of nomogram prediction model for postoperative 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 described as absolute numbers. The COX proportional hazard model was used for univariate and multivariate analyses. The R software(3.5.1 version) was used to construct nomogram prediction model. The receiver operating characteristic (ROC) curve was drawn and the area under curve (AUC) was used to evaluate the efficacy of the nomogram prediction model. The Bootstrap method was used for internal verification and to calculate the average consistency index (C-index). Results:(1) Surgical situations. All 812 patients underwent laparoscopic ISR for extremely low rectal cancer, including 388 cases undergoing partial ISR, 218 cases undergoing subtotal ISR and 206 cases undergoing complete ISR. All 812 patients underwent ileal protective ostomy, and there were 306 cases with double anastomosis and 203 cases with left colic artery preserved, respectively. The operation time and volume of intraoperative blood loss of 812 patients was (179±33)minutes and (33±13)mL, respectively. (2) Follow-up. All 812 patients were followed up for (13.5±0.9)months. Of the 812 patients, there were 62 cases with postoperative anastomotic leakage and the healing time of these cases was (33±6)days. (3) Influencing factors of postoperative anastomotic leakage. Results of multivariate analysis showed that male, neoadjuvant chemoradiotherapy, failure of reser-ving left colic artery were independent risk factors of anastomotic leakage after laparoscopic ISR for extremely low rectal cancer ( hazard ratio=5.98, 4.00, 16.26, 95% confidence interval as 1.66-24.12, 1.30-12.42, 3.00-90.89, P<0.05). (4) Construction and evaluation of nomogram prediction model for postoperative anastomotic leakage. According to the results of multivariate analysis, male, neoadju-vant chemoradiotherapy and failure of reserving left colic artery were used to construct the nomogram prediction model for anastomotic leakage after laparoscopic ISR for extremely low rectal cancer, and the score of these indexes in the nomogram prediction model was 50, 49, 93, respectively. The total score of these index corresponded to the incidence rate of anastomotic leakage. Results of ROC curve showed that the AUC of nomogram prediction model of anastomotic leakage after laparoscopic ISR for extremely low rectal cancer was 0.87 (95% confidence interval as 0.80-0.93, P<0.05), with sensi-tivity and specificity 0.96 and 0.60, respectively. Results of internal verification showed that the C-index of nomogram prediction model was 0.87. Conclusion:Male, neoadjuvant chemoradiotherapy, failure of reserving left colic artery are independent risk factors of anastomotic leakage after laparo-scopic ISR for extremely low rectal cancer, and the nomogram prediction model based on these indexes can predict the incidence rate of postoperative anastomotic leakage.

Objective:To investigate the construction and application value of a nomogram predictive model for the prognosis of rectal cancer liver metastases based on Surveillance, Epidemio-logy, and End Results (SEER) database.Methods:The retrospective cohort study was conducted. The clinicopathological data of 6 192 patients with rectal cancer liver metastases in the SEER database ( http://seer.cancer.gov/) and 312 patients who were admitted to The Second Affiliated Hospital of Naval Medical University January 2010 to December 2016 were collected. Of 6 192 patients, there were 3 592 males and 2 600 cases. There were 1 076 cases with age lower than 50 years, 2 862 cases with age as 50-69 years, 2 254 cases with age equal to or more than 70 years, respectively. Of 312 pati-ents, there were 177 males and 135 cases. There were 51 cases with age lower than 50 years, 155 cases with age as 50-69 years, 109 cases with age equal to or more than 70 years, respectively. Patients of the SEER database were set as the training set, and patients in The Second Affiliated Hospital of Naval Medical University were set as the validation set. Univariate and multivariate COX proportional hazards regression models were used to analyze risk factors associated with prognosis, and construct and verify the accuracy of nomogram predictive model for the prognosis of rectal cancer liver metas-tasis. The training set were used to construct the nomogram prediction model, and the validation set were used to verify its performance. Observation indicators: (1) prognostic factors analysis in patients with rectal cancer liver metastases; (2) construction and verificative of the predictive model for the prognosis of rectal cancer liver metastasis. Measurement data with normal distribution were represented as Mean± SD, and comparison between groups was conducted using the t test. Count data were described as absolute numbers or percentages, and comparison between groups was conducted using the chi-square test. Comparison of ordinal data was analyzed using the rank sum test. The COX regression model was used for univariate and multivariate analyses. Kaplan-Meier method was used to calculate survival rates, and Log-Rank test was used for survival analysis. Results:(1) Prognostic factors analysis in patients with rectal cancer liver metastases. Results of multivariate analysis showed that age >50 years, TNM Ⅱ-Ⅳ stage, stage T3-T4, stage N1-N2, the number of lymph nodes dissected <12, tumor diameter >5.1 cm, positive carcinoembryonic antigen, peripheral nerve infiltration, radiotherapy and adjuvant chemotherapy, poorly differentiated or undifferented tumor were independent prognostic factors of patients ( P<0.05). (2) Construction and verification of the predictive model for the prognosis of rectal cancer liver metastasis. A nomogram predictive model for the prognosis of rectal cancer liver metastasis was constructed based in the multivariate analysis. The C-index of the nomogram predictive model was 0.91, with area under the curve as 0.726, indicating a good discriminant ability. Results of the calibration curve in validation dataset showed that the colorectal cancer survival rate predicted by the nomogram predictive model was consistent with the actual survival rate. Conclusion:The nomogram predictive model can accurately predict the survival probability of patients with rectal cancer liver metastases.