Objective:To analyze the differences in clinicopathological features of colon cancers and survival between patients with right- versus left-sided colon cancers.Methods:This was a retrospective cohort study. Information on patients with colon cancer from January 2016 to August 2020 was collected from the prospective registry database at Peking Union Medical College Hospital . Primary tumors located in the cecum, ascending colon, and proximal two‐thirds of the transverse colon were defined as right-sided colon cancers (RCCs), whereas primary tumors located in the distal third of the transverse colon, descending colon, or sigmoid colon were defined as left‐sided colon cancers (LCCs). Clinicopathological features were compared using the χ 2 test or Mann‐Whitney U test. Survival was estimated by Kaplan‐Meier curves and the log‐rank test. Factors that differed significantly between the two groups were identified by multivariate survival analyses performed with the Cox proportional hazards function. One propensity score matching was performed to eliminate the effects of confounding factors. Results:The study cohort comprised 856 patients, with TNM Stage I disease, 391 (45.7%) with Stage II, and 336 (39.3%) with Stage III, including 442 (51.6%) with LCC and 414 (48.4%) with RCC and 129 (15.1%). Defective mismatch repair (dMMR) was identified in 139 patients (16.2%). Compared with RCC, the proportion of men (274/442 [62.0%] vs. 224/414 [54.1%], χ 2=5.462, P=0.019), body mass index (24.2 [21.9, 26.6] kg/m 2 vs. 23.2 [21.3, 25.5] kg/m 2, U=78,789.0, P<0.001), and well/moderately differentiated cancer (412/442 [93.2%] vs. 344/414 [83.1%], χ 2=22.266, P<0.001) were higher in the LCC than the RCC group. In contrast, the proportion of dMMR (40/442 [9.0%] vs. 99/414 [23.9%], χ 2=34.721, P<0.001) and combined vascular invasion (106/442[24.0%] vs. 125/414[30.2%], χ 2=4.186, P=0.041) were lower in the LCC than RCC group. The median follow‐up time for all patients was 48 (range 33, 59) months. The log‐rank test revealed no significant differences in disease-free survival (DFS) ( P=0.668) or overall survival (OS) ( P=0.828) between patients with LCC versus RCC. Cox proportional hazards model showed that dMMR was significantly associated with a longer DFS (HR=0.419, 95%CI: 0.204?0.862, P=0.018), whereas a higher proportion of T3‐4 (HR=2.178, 95%CI: 1.089?4.359, P=0.028), N+ (HR=2.126, 95%CI: 1.443?3.133, P<0.001), and perineural invasion (HR=1.835, 95%CI: 1.115?3.020, P=0.017) were associated with poor DFS. Tumor location was not associated with DFS or OS (all P>0.05). Subsequent analysis showed that RCC patients with dMMR had longer DFS than did RCC patients with pMMR (HR=0.338, 95%CI: 0.146?0.786, P=0.012). However, the difference in OS between the two groups was not statistically significant (HR=0.340, 95%CI:0.103?1.119, P=0.076). After propensity score matching for independent risk factors for DFS, the log‐rank test revealed no significant differences in DFS ( P=0.343) or OS ( P=0.658) between patients with LCC versus RCC, whereas patient with dMMR had better DFS ( P=0.047) and OS ( P=0.040) than did patients with pMMR. Conclusions:Tumor location is associated with differences in clinicopathological features; however, this has no impact on survival. dMMR status is significantly associated with longer survival: this association may be stronger in RCC patients.

Objective:To explore the impact on safety and prognosis in patients with right-sided colon cancer participating in surgical clinical research.Methods:This retrospective cohort study utilized data from a randomized controlled trial (RELARC study) conducted by the colorectal surgery group at Peking Union Medical College Hospital in which laparoscopic complete mesocolic excision (CME) was compared with D2 radical resection for the management of right-sided colon cancer. The eligibility criteria were age 18–75 years, biopsy-proven colon adenocarcinoma, tumor located between the cecum and right 1/3 of the transverse colon, enhanced chest, abdomen, and pelvic CT scans suggesting tumor stage T2–T4N0M0 or TanyN+ M0, and having undergone radical surgical treatment from January 2016 to December 2019. Exclusion factors included multiple primary colorectal cancers, preoperative stage T1N0 or enlarged central lymph nodes, tumor involving surrounding organs requiring their resection, definite distant metastasis or otherwise unable to undergo R0 resection, history of any other malignant tumors within previous 5 years, intestinal obstruction, perforation, or gastrointestinal bleeding requiring emergency surgery, and assessed as unsuitable for laparoscopic surgery. Patients who had participated in the RELARC study were included in the RELARC group, whereas those who met the inclusion criteria but refused to participate in the RELAEC study were included in the control group. The main indicators studied were the patient's baseline data, surgery and perioperative conditions, pathological characteristics, adjuvant treatment, and postoperative follow-up (including average frequency of follow-up within the first 3 years) and survival (including 3-year disease-free survival rate (DFS) and 3-year overall survival rate (OS). Differences in these indicators between the RELARC and control groups were compared.Results:The study cohort comprised 290 patients, 173 in the RELARC group (RELARC-CME group, 82; RELARC-D2 group, 91) and 117 in the control group (CME control group, 72; D2 control group, 45). There was a significantly higher proportion of overweight patients (BMI ≥24 kg/m 2) in the RELARC-CME than in the CME control group (67.1% [55/82] vs. 33.3% [24/72], χ 2=17.469, P<0.001). There were no other statistically significant differences in baseline characteristics (all P>0.05). No significant disparities were found between the CME and D2 groups in terms of operation duration, intraoperative blood loss, rate of conversion to open surgery, combined organ resection, intraoperative blood transfusion, or intraoperative complications (all P>0.05). There was a trend toward Clavien–Dindo grade II or higher postoperative complications in the RELARC-CME group (24.4% [20/82]) than in the CME control group (18.1% [13/72]); however, this difference was not statistically significant (χ 2=0.914, P=0.339). Similarly, the difference in this rate did not differ significantly between the RELARC-D2 group (25.3% [23/91]) and D2 control group (24.4% [11/45], χ 2=0.011, P=0.916). The median duration of postoperative follow-up was significantly shorter in the RELARC groups than in the corresponding control groups. Specifically, the median duration of follow-up was 4.5 (4.5, 4.5) months in the RELARC-CME and 7.2 (6.0, 9.0) months in the CME control group ( Z=-10.608, P<0.001). Similarly, the median duration of follow-up was 4.5 (4.5, 4.5) months in the RELARC-D2 group as opposed to 8.3 (6.6, 9.0) months in the D2 control group ( Z=-10.595, P<0.001). The 3-year DFS rate (91.5%) and OS rate (96.3%) tended to be higher in the RELARC-CME group than in the CME control group (84.7% and 90.3%, respectively). The 3-year DFS rate (87.9%) and OS rate (96.7%) tended to be higher in the RELARC-D2 group than in the D2 control group (81.8% and 88.6%, respectively); however, these differences were not statistically significant (all P>0.05). Subgroup analysis according to pathological stage revealed that patients in the RELARC-D2 group with pN0 stage achieved a significantly superior 3-year OS rate than did those in the D2 control group (100% vs. 88.9%, P=0.008). We identified no statistically significant differences in survival rates between the remaining subgroups (all P>0.05). Conclusions:A high-quality surgical clinical trial with close follow-up can achieve perioperative safety and a trend toward improved survival outcomes.

Objective:To analyze the differences in clinicopathological features of colon cancers and survival between patients with right- versus left-sided colon cancers.Methods:This was a retrospective cohort study. Information on patients with colon cancer from January 2016 to August 2020 was collected from the prospective registry database at Peking Union Medical College Hospital . Primary tumors located in the cecum, ascending colon, and proximal two‐thirds of the transverse colon were defined as right-sided colon cancers (RCCs), whereas primary tumors located in the distal third of the transverse colon, descending colon, or sigmoid colon were defined as left‐sided colon cancers (LCCs). Clinicopathological features were compared using the χ 2 test or Mann‐Whitney U test. Survival was estimated by Kaplan‐Meier curves and the log‐rank test. Factors that differed significantly between the two groups were identified by multivariate survival analyses performed with the Cox proportional hazards function. One propensity score matching was performed to eliminate the effects of confounding factors. Results:The study cohort comprised 856 patients, with TNM Stage I disease, 391 (45.7%) with Stage II, and 336 (39.3%) with Stage III, including 442 (51.6%) with LCC and 414 (48.4%) with RCC and 129 (15.1%). Defective mismatch repair (dMMR) was identified in 139 patients (16.2%). Compared with RCC, the proportion of men (274/442 [62.0%] vs. 224/414 [54.1%], χ 2=5.462, P=0.019), body mass index (24.2 [21.9, 26.6] kg/m 2 vs. 23.2 [21.3, 25.5] kg/m 2, U=78,789.0, P<0.001), and well/moderately differentiated cancer (412/442 [93.2%] vs. 344/414 [83.1%], χ 2=22.266, P<0.001) were higher in the LCC than the RCC group. In contrast, the proportion of dMMR (40/442 [9.0%] vs. 99/414 [23.9%], χ 2=34.721, P<0.001) and combined vascular invasion (106/442[24.0%] vs. 125/414[30.2%], χ 2=4.186, P=0.041) were lower in the LCC than RCC group. The median follow‐up time for all patients was 48 (range 33, 59) months. The log‐rank test revealed no significant differences in disease-free survival (DFS) ( P=0.668) or overall survival (OS) ( P=0.828) between patients with LCC versus RCC. Cox proportional hazards model showed that dMMR was significantly associated with a longer DFS (HR=0.419, 95%CI: 0.204?0.862, P=0.018), whereas a higher proportion of T3‐4 (HR=2.178, 95%CI: 1.089?4.359, P=0.028), N+ (HR=2.126, 95%CI: 1.443?3.133, P<0.001), and perineural invasion (HR=1.835, 95%CI: 1.115?3.020, P=0.017) were associated with poor DFS. Tumor location was not associated with DFS or OS (all P>0.05). Subsequent analysis showed that RCC patients with dMMR had longer DFS than did RCC patients with pMMR (HR=0.338, 95%CI: 0.146?0.786, P=0.012). However, the difference in OS between the two groups was not statistically significant (HR=0.340, 95%CI:0.103?1.119, P=0.076). After propensity score matching for independent risk factors for DFS, the log‐rank test revealed no significant differences in DFS ( P=0.343) or OS ( P=0.658) between patients with LCC versus RCC, whereas patient with dMMR had better DFS ( P=0.047) and OS ( P=0.040) than did patients with pMMR. Conclusions:Tumor location is associated with differences in clinicopathological features; however, this has no impact on survival. dMMR status is significantly associated with longer survival: this association may be stronger in RCC patients.

Objective:To explore the impact on safety and prognosis in patients with right-sided colon cancer participating in surgical clinical research.Methods:This retrospective cohort study utilized data from a randomized controlled trial (RELARC study) conducted by the colorectal surgery group at Peking Union Medical College Hospital in which laparoscopic complete mesocolic excision (CME) was compared with D2 radical resection for the management of right-sided colon cancer. The eligibility criteria were age 18–75 years, biopsy-proven colon adenocarcinoma, tumor located between the cecum and right 1/3 of the transverse colon, enhanced chest, abdomen, and pelvic CT scans suggesting tumor stage T2–T4N0M0 or TanyN+ M0, and having undergone radical surgical treatment from January 2016 to December 2019. Exclusion factors included multiple primary colorectal cancers, preoperative stage T1N0 or enlarged central lymph nodes, tumor involving surrounding organs requiring their resection, definite distant metastasis or otherwise unable to undergo R0 resection, history of any other malignant tumors within previous 5 years, intestinal obstruction, perforation, or gastrointestinal bleeding requiring emergency surgery, and assessed as unsuitable for laparoscopic surgery. Patients who had participated in the RELARC study were included in the RELARC group, whereas those who met the inclusion criteria but refused to participate in the RELAEC study were included in the control group. The main indicators studied were the patient's baseline data, surgery and perioperative conditions, pathological characteristics, adjuvant treatment, and postoperative follow-up (including average frequency of follow-up within the first 3 years) and survival (including 3-year disease-free survival rate (DFS) and 3-year overall survival rate (OS). Differences in these indicators between the RELARC and control groups were compared.Results:The study cohort comprised 290 patients, 173 in the RELARC group (RELARC-CME group, 82; RELARC-D2 group, 91) and 117 in the control group (CME control group, 72; D2 control group, 45). There was a significantly higher proportion of overweight patients (BMI ≥24 kg/m 2) in the RELARC-CME than in the CME control group (67.1% [55/82] vs. 33.3% [24/72], χ 2=17.469, P<0.001). There were no other statistically significant differences in baseline characteristics (all P>0.05). No significant disparities were found between the CME and D2 groups in terms of operation duration, intraoperative blood loss, rate of conversion to open surgery, combined organ resection, intraoperative blood transfusion, or intraoperative complications (all P>0.05). There was a trend toward Clavien–Dindo grade II or higher postoperative complications in the RELARC-CME group (24.4% [20/82]) than in the CME control group (18.1% [13/72]); however, this difference was not statistically significant (χ 2=0.914, P=0.339). Similarly, the difference in this rate did not differ significantly between the RELARC-D2 group (25.3% [23/91]) and D2 control group (24.4% [11/45], χ 2=0.011, P=0.916). The median duration of postoperative follow-up was significantly shorter in the RELARC groups than in the corresponding control groups. Specifically, the median duration of follow-up was 4.5 (4.5, 4.5) months in the RELARC-CME and 7.2 (6.0, 9.0) months in the CME control group ( Z=-10.608, P<0.001). Similarly, the median duration of follow-up was 4.5 (4.5, 4.5) months in the RELARC-D2 group as opposed to 8.3 (6.6, 9.0) months in the D2 control group ( Z=-10.595, P<0.001). The 3-year DFS rate (91.5%) and OS rate (96.3%) tended to be higher in the RELARC-CME group than in the CME control group (84.7% and 90.3%, respectively). The 3-year DFS rate (87.9%) and OS rate (96.7%) tended to be higher in the RELARC-D2 group than in the D2 control group (81.8% and 88.6%, respectively); however, these differences were not statistically significant (all P>0.05). Subgroup analysis according to pathological stage revealed that patients in the RELARC-D2 group with pN0 stage achieved a significantly superior 3-year OS rate than did those in the D2 control group (100% vs. 88.9%, P=0.008). We identified no statistically significant differences in survival rates between the remaining subgroups (all P>0.05). Conclusions:A high-quality surgical clinical trial with close follow-up can achieve perioperative safety and a trend toward improved survival outcomes.

Objective:To investigate the interactive effect of mismatch repair (MMR) protein status and adverse clinicopathological features on prognosis of stage Ⅰ-Ⅲ colon cancer.Methods:The retrospective cohort study was conducted. The clinicopathological data of 1 650 patients with colon cancer of stage Ⅰ-Ⅲ who were admitted to 7 hospitals in China from January 2016 to December 2017 were collected. There were 963 males and 687 females, aged 62(53,71)years. Patients were classified as 230 cases of MMR deficiency (dMMR) and 1 420 cases of MMR proficiency (pMMR) based on their MMR protein status. Observation indicators: (1) comparison of clinicopathological characteristics between patients of different MMR protein status; (2) analysis of factors affecting the survival outcomes of patients of dMMR; (3) analysis of factors affecting the survival outcomes of patients of pMMR; (4) interaction analysis of MMR and adverse clinicopathological features on survival outcomes. Measurement data with normal distribution were represented as Mean± SD, and comparison between groups was conducted using the independent t test. Measurement data with skewed distribution were represented as M( Q1, Q3), and comparison between groups was conducted using the Mann-Whitney U test. Count data were described as absolute numbers, and comparison between groups was conducted using the chi-square test or Fisher exact probability. Comparison of ordinal data was conducted using the Mann-Whitney U test. The random forest interpolation method was used for missing values in data interpolation. Univariate analysis was conducted using the COX proportional risk regression model, and multivariate analysis was conducted using the COX stepwise regression with forward method. The coefficient of multiplication interaction effect was obtained using the interaction term coefficient of COX proportional risk regression model. Evaluation of additive interaction effects was conducted using the relative excess risk due to interaction ( RERI). Results:(1) Comparison of clinicopathological characteristics between patients of different MMR protein status. There were significant differences in age, T staging, the number of lymph node harvest, the number of lymph node harvest <12, high grade tumor between patients of dMMR and pMMR ( P<0.05). (2) Analysis of factors affecting the survival outcomes of patients of dMMR. Results of multivariate analysis showed that T staging, N staging, the number of lymph node harvest <12 were independent factors affecting the disease-free survival (DFS) of colon cancer patients of dMMR ( hazard ratio=3.548, 2.589, 6.702, 95% confidence interval as 1.460-8.620, 1.064-6.301, 1.886-23.813, P<0.05). Age and N staging were independent factors affecting the overall survival (OS) of colon cancer patients of dMMR ( hazard ratio=1.073, 10.684, 95% confidence interval as 1.021-1.126, 2.311-49.404, P<0.05). (3) Analysis of factors affecting the survival outcomes of patients of pMMR. Results of multivariate analysis showed that age, T staging, N staging, vascular tumor thrombus were independent factors affecting the DFS of colon cancer patients of pMMR ( hazard ratio=1.018, 2.214, 2.598, 1.549, 95% confidence interval as 1.006-1.030, 1.618-3.030, 1.921-3.513, 1.118-2.147, P<0.05). Age, T staging, N staging, high grade tumor were independent factors affecting the OS of colon cancer patients of pMMR ( hazard ratio=1.036, 2.080, 2.591, 1.615, 95% confidence interval as 1.020-1.052, 1.407-3.075, 1.791-3.748, 1.114-2.341, P<0.05). (4) Interaction analysis of MMR and adverse clinicopathological features on survival outcomes. Results of interaction analysis showed that the multiplication interaction effect between the number of lymph node harvest <12 and MMR protein status was significant on DFS of colon cancer patients ( hazard ratio=3.923, 95% confidence interval as 1.057-14.555, P<0.05). The additive interaction effects between age and MMR protein status, between high grade tumor and MMR protein status were significant on OS of colon cancer patients ( RERI=-0.033, -1.304, 95% confidence interval as -0.049 to -0.018, -2.462 to -0.146). Conclusions:There is an interaction between the MMR protein status and the adverse clinicopathological features (the number of lymph node harvest <12, high grade tumor) on prognosis of colon cancer patients of stage Ⅰ-Ⅲ. In patients of dMMR, the number of lymph node harvest <12 has a stronger predictive effect on poor prognosis. In patients of pMMR, the high grade tumor has a stronger predictive effect on poor prognosis.

Objective:To investigate the incidence and influencing factors of anastomotic leakage after laparoscopic anterior resection for rectal cancer.Methods:The retrospective case-control study was conducted. The clinicopathological data of 804 patients with rectal cancer who were admitted to Peking Union Medical College Hospital of Chinese Academy of Medical Sciences from January 2017 to December 2019 were collected. There were 521 male and 283 female, aged 63(range, 27-94)years. All 804 patients underwent laparoscopic anterior resection for rectal cancer. Observation indicators: (1) surgical situations; (2) incidence of postoperative anastomotic leakage; (3) follow-up; (4) influencing factors of postoperative anastomotic leakage; (5) subgroup analysis. Measurement data with normal distribution were represented as Mean± SD, and comparison between groups was conducted using the independent sample t test. Measurement data with skewed distribu-tion were represented as M(range), and comparison between groups was conducted using the Mann-Whitney U test. Count data were described as absolute numbers or percentages, and comparison between groups was conducted using the chi-square test or Fisher exact probability. Univariate analysis was conducted using the chi-square test or independent sample t test. Factors with P≤0.2 in univariate analysis were included in multivariate Logistic regression analysis. Results:(1) Surgical situations. All 804 patients underwent laparoscopic radical resection of upper and middle rectal cancer successfully, with the operation time and volume of intraoperative blood loss as 135(range, 118-256)minutes and 30(range, 5-350)mL. All 804 patients completed end-to-end colon rectal anastomosis, including 287 patients with reinforced sutures at the anastomotic site, and 517 patients with routine anastomosis. (2) Incidence of postoperative anastomotic leakage. Of the 804 patients, 40 patients had postoperative anastomotic leakage, with the incidence rate as 4.98%(40/804). (3) Follow-up. All 804 patients were followed up for 32(range, 6-49)months. None of patient died during the perioperative period. (4) Influencing factors of postoperative anastomotic leakage. Results of multivariate analysis showed that unreinforced suture at the anastomotic site was an independent risk factor for postoperative anastomotic leakage ( odds ratio=2.78, 95% confidence interval as 1.21-6.37, P<0.05). (5) Subgroup analysis. Of the 804 patients, 202 patients received neoadjuvant therapy and 602 patients did not receive neoadjuvant therapy. Of the 602 patients who did not receive neo-adjuvant therapy, cases with postoperative anastomotic leakage was 6 in the 253 patients with reinforced sutures, versus 21 in the 349 patients with routine sutures, showing a significant difference between them ( χ2=4.56, P<0.05). Conclusion:Unreinforced anastomosis at the anasto-motic site is an independent risk factor for anastomotic leakage after laparoscopic anterior rectal resection, especially for rectal cancer patients without neoadjuvant radiochemotherapy.

Objective:To examine the prognosis factors of postoperative cardiac complications in colorectal cancer patients co-morbidated with coronary artery disease.Methods:Clinical data of 449 patients colorectal cancer patients co-morbidated with coronary artery disease accepted redical surgery from April 2013 to April 2020 at Department of General Surgery, Peking Union Medical College Hospital were analyzed retrospectively. There were 306 males and 143 females, aging (68.7±8.9) years (range: 44 to 89 years). Postoperative acute coronary syndrome, new-onset arrhythmia and heart failure that causes clinical symptoms were recorded as cardiac complications. t test, χ 2 test and Fisher exact test were used for univariate analysis of prognosis factors of postoperative cardiac events. The variables with P<0.05 were included in the multivariate Logistic regression was used to determine the independent prognosis factors. Results:After surgery, 44 patients (9.8%) suffered from at least one cardiac event, including 30 patients with acute coronary syndrome, 19 patients with new-onset arrhythmia and 9 patients with heart failure. There were 3 deaths in the cohort within 30 days after surgery. Two patients died from cardiac-related complications, and one from septic shock due to postoperative anastomotic leaks. On Univariate analysis showed that cardiac complications were associated with age ≥80 years, co-morbidated diabetes, emergency surgery, re-operation, anastomotic leakage, intestinal flora disorder and elevation of preoperative neutrophil-lymphocyte ratio (χ 2: 4.308 to 12.219, all P<0.05). Multivariate Logistic regression analysis identified age ≥80 years ( OR=3.195, 95% CI: 1.379 to 7.407, P=0.007), co-morbidated diabetes ( OR=2.551, 95% CI: 1.294 to 5.025, P=0.007), emergency surgery ( OR=4.717, 95% CI: 1.052 to 20.833, P=0.043), and elevated preoperative neutrophil-lymphocyte ratio ( OR=1.114, 95% CI: 1.018 to 1.218, P=0.018) as independent prognosis factors for cardiac complications. Conclusions:Emergency surgery, advanced age, co-morbidated type 2 diabetes and elevated preoperative neutrophil-lymphocyte ratio may increase the risk of postoperative cardiac complications in colorectal cancer patients with coronary artery disease. Surgeons should strictly master surgical indications, pay attention to preoperative assessment, perioperative monitoring, and diagnosis and treatment of postoperative complications in order to reduce the risk of complications.

Objective:To examine the prognosis factors of postoperative cardiac complications in colorectal cancer patients co-morbidated with coronary artery disease.Methods:Clinical data of 449 patients colorectal cancer patients co-morbidated with coronary artery disease accepted redical surgery from April 2013 to April 2020 at Department of General Surgery, Peking Union Medical College Hospital were analyzed retrospectively. There were 306 males and 143 females, aging (68.7±8.9) years (range: 44 to 89 years). Postoperative acute coronary syndrome, new-onset arrhythmia and heart failure that causes clinical symptoms were recorded as cardiac complications. t test, χ 2 test and Fisher exact test were used for univariate analysis of prognosis factors of postoperative cardiac events. The variables with P<0.05 were included in the multivariate Logistic regression was used to determine the independent prognosis factors. Results:After surgery, 44 patients (9.8%) suffered from at least one cardiac event, including 30 patients with acute coronary syndrome, 19 patients with new-onset arrhythmia and 9 patients with heart failure. There were 3 deaths in the cohort within 30 days after surgery. Two patients died from cardiac-related complications, and one from septic shock due to postoperative anastomotic leaks. On Univariate analysis showed that cardiac complications were associated with age ≥80 years, co-morbidated diabetes, emergency surgery, re-operation, anastomotic leakage, intestinal flora disorder and elevation of preoperative neutrophil-lymphocyte ratio (χ 2: 4.308 to 12.219, all P<0.05). Multivariate Logistic regression analysis identified age ≥80 years ( OR=3.195, 95% CI: 1.379 to 7.407, P=0.007), co-morbidated diabetes ( OR=2.551, 95% CI: 1.294 to 5.025, P=0.007), emergency surgery ( OR=4.717, 95% CI: 1.052 to 20.833, P=0.043), and elevated preoperative neutrophil-lymphocyte ratio ( OR=1.114, 95% CI: 1.018 to 1.218, P=0.018) as independent prognosis factors for cardiac complications. Conclusions:Emergency surgery, advanced age, co-morbidated type 2 diabetes and elevated preoperative neutrophil-lymphocyte ratio may increase the risk of postoperative cardiac complications in colorectal cancer patients with coronary artery disease. Surgeons should strictly master surgical indications, pay attention to preoperative assessment, perioperative monitoring, and diagnosis and treatment of postoperative complications in order to reduce the risk of complications.

Objective:To evaluate the clinical efficacy of transanal total mesorectal excision (taTME) on transanal endoscopic microsurgery (TEM) platform in the treatment of middle and low rectal cancer.Methods:The retrospective and descriptive study was conducted. The clinico-pathological data of 28 patients with middle and low rectal cancer who underwent taTME on TEM platform in the Peking Union Medical College Hospital of Chinese Academy of Medical Science from October 2014 to October 2017 were collected. There were 21 males and 7 females, aged 59 years (51 years, 68 years). Observation indicators: (1) surgical and postoperative situations; (2) follow-up. Follow-up was conducted using outpatient examination or telephone interview to detect post-operative defecation function and survival of patients up to October 2020. Patients underwent physical examination, examination of tumor markers including carcinoembryonic antigen and CA19-9, colonoscopy, rectal magnetic resonance imaging, thoracoabdominal and pelvic enhanced computed tomography (CT) and (or) PET-CT examination during the follow-up. Measurement data with normal distribution were represented as Mean±SD, and comparison between groups was analyzed using the independent sample t test. Measurement data with skewed distribution were represented as M( P25,P75) or M (range), and comparison between groups was analyzed using the non parameter Mann-Whitney U test. Count data were described as absolute numbers or percentages, and comparison between groups was analyzed using the chi-square test or Fisher exact probability. Results:(1) Surgical and postoperative situations: 28 patients underwent successful surgery, without intra-operative conversion to laparotomy. Of 28 patients, 24 cases underwent colorectal anastomosis and 4 cases underwent colon-anal anastomosis. Twenty-six cases underwent primary protective enterostomy and 2 cases didn't undergo primary protective enterostomy. The operation time of 28 patients was (182±37)minutes and the volume of intraoperative blood loss was 40mL(30 mL, 55 mL). One patient with intraoperative presacral hemorrhage received compression hemostasis. Eleven patients had postoperative complications, including 4 cases with anastomotic leakage, 2 cases with alteration of intestinal flora, 2 cases with paralytic ileus, 2 cases with urinary retention, 2 cases with urinary infection, 1 case with prolapse necrosis of small intestinal stoma, 1 case with anal hemorrhage, 1 case with rectovaginal fistula, 1 case with pelvic infection; some patients had multiple complications. Three patients had non-planned reoperation. One case without primary protective enterostomy had anastomotic leakage at postoperative 3 days, and was improved after emergency transversostomy. One case had prolapse necrosis of small intestinal stoma at postoperative 3 days and was improved after emergency enterostomy and reconstruction. One case with anal hemorrhage was stopped hemorrhage under anoscopy. Patients with other complications were cured after conservative treatments. The duration of postoperative hospital stay of 28 patients was 8 days(7 days, 9 days). Results of pathological examination in 28 patients showed 16 cases of moderately differentiated adenocarcinoma, 3 cases of moderately to highly differentiated adenocarcinoma, 5 cases of highly differentiated adenocarcinoma, 1 case of mucinous adenocarcinoma, 3 cases of pathological complete response. TNM staging of 28 patients showed 3 cases in stage T0N0, 4 cases in stage T1N0, 6 cases in stage T2N0, 4 cases in stage T2N1, 7 cases in stage T3N0, 3 cases in stage T3N1, 1 case in stage T4N1. The distance from tumor to distal margin was (2.2±1.7)cm. The surgical specimens of 28 patients showed negative for proximal, distal and circumferential margins. The number of lymph node dissection was 15±7. The complete rate of total mesorectal excision was 100%(28/28). Eleven of 28 patients underwent neoadjuvant therapy and 17 patients didn't receive neoadjuvant therapy. The tumor diameter, distance from tumor to anal margin, operation time, volume of intraoperative blood loss, duration of postoperative hospital stay were 2 cm(1 cm, 4 cm), 5 cm(4 cm, 6 cm), (187±25)minutes, 45 mL(38 mL, 53 mL), 8 days(7 days, 12 days) for patients with neoadjuvant therapy, respectively, versus 3 cm(2 cm, 4 cm), 5 cm(4 cm, 6 cm), (177±35)minutes, 40 mL(30 mL, 60 mL), 8 days(7 days, 8 days) for patients without neoadjuvant therapy, showing no significant difference between the two groups ( Z=-1.127, -0.293, t=0.590, Z=-0.790, -0.876, P>0.05). (2) Follow-up: 23 of 28 patients were followed up for (44±14)months. Of the 23 patients,11 cases were classified as grade A of Williams score for defecation function at postoperative 6 months, 8 cases were classified as grade B and 4 cases were classified as grade C. Eighteen of 23 patients with follow-up had disease-free survival, 1 of whom didn't undergo stoma closure due to anastomotic stenosis at postoperative 6 months. Three patients had distant metastasis, including 1 case with parastomal implantation metastasis, 1 case with sacral metastasis, 1 case with pulmonary metastasis. Two patients died, 1 case of whom died of urinary obstruction and 1 case with mucinous adenocarcinoma died at postoperative 24 months. Conclusion:TaTME based on TEM platform is feasible for middle and low rectal cancer, which has the advantages of preserving anus and negative circumferential margin.

Objective:To investigate the clinical efficacy of laparoscopic resection of retrorectal cystic lesions.Methods:The retrospective and descriptive study was conducted. The clinicopathological data of 58 patients undergoing laparoscopic resection of retrorectal cystic lesions in the Peking Union Medical College Hospital, Chinese Academy of Medical Sciences from August 2012 to August 2019 were collected. There were 5 males and 53 females, aged from 15 to 70 years, with a median age of 38 years. All the 58 patients underwent laparoscopic resection of retrorectal cystic lesions and the combined operation through the transsacral approach was chosen according to the patient condition. Observation indicators: (1) surgical situations; (2) postoperative situations; (3) postoperative histopathological examination; (4) follow-up. Patients were followed up regularly using outpatient examination once every 6 months during the first postoperative year and once every 12 months after the first postoperative year. The recurrence of cysts was evaluated by computed tomography or magnetic resonance imaging examinations during the follow-up up to August 2020. Measurement data with normal distribution were represented as Mean± SD and measurement data with skewed distribution were described as M(range). Count data were described as absolute numbers. Results:(1) Surgical situations: of the 58 patients, 54 cases underwent laparoscopic resection of retrorectal cystic lesions and 4 cases underwent laparoscopic resection of retrorectal cystic lesions combined with the transsacral approach operation. One of the 58 patients who had a huge cyst surrounding the rectum underwent transverse colostomy after repairing the damage of separated posterior wall of rectum. Two cases underwent preventive transverse colostomy because the external rectal wall heat injury could not be excluded after separation of the tight adhesion between cyst and rectum. The operation time and volume of intraoperative blood loss were (123±56)minutes, 20 mL(range, 5?500 mL) of 54 cases who underwent laparoscopic resection of retrorectal cystic lesions and (232±38)minutes, 90 mL(range, 30?800 mL) of 4 cases who underwent laparoscopic resection of retrorectal cystic lesions combined with the transsacral approach operation, respectively. (2) Postoperative situations: 7 of the 58 patients had complica-tions. Of the 7 patients, 2 cases had postoperative rectal fistula and were cured after the treatment of transverse colostomy combined with pelvic drainage, 2 cases had postoperative urinary tract infection and were relieved after anti-infection treatment, 2 cases had urinary retention after removal of catheter and were recovered after 3 weeks of re-indwelling catheter, and 1 case had poor incision healing of transsacral and was healed after wound dressing change. The duration of postoperative hospital stay of the 58 patients was (7±4)days. (3) Postoperative histopathological examination: results of the postoperative histopathological examination showed that there were 26 of 58 patients with epidermoid cyst, 20 patients with teratoma (2 cases with mature teratoma accompanied by mucinous adenocarcinoma and 1 case with mature teratoma accompanied by neuroendocrine carcinoma), 10 patients with dermoid cyst, and 2 patients with tailgut cyst. (4) Follow-up: 57 of the 58 patients were followed up for 2-85 months, with a median follow-up time of 51 months. Of the 57 patients who were followed up, 1 patient was diagnosed with buttock subcutaneous cyst at postoperative 8 months and treated with local excision, 1 patient was diagnosed with a small presacral cyst recurrence by pelvic magnetic resonance imaging at postoperative 6 months and continued follow-up as the cyst without obvious enlargement, and the other 55 patients had no cyst recurrence.Conclusion:The laparoscopic resection of retrorectal cystic lesions is safe and feasible.