3587 Background: Neoadjuvant chemoradiotherapy is currently the standard strategy for microsatellite stable (MSS) / mismatch repair-proficient (pMMR) locally advanced rectal cancer (LARC) patients. This study aimed to explore the safety and efficacy of combining specific (thymalfasin) and non-specific (tislelizumab) tumor immunotherapy with chemoradiotherapy in MSS/pMMR LARC. Methods: This trial is an open, prospective, multi-center, single-arm phase II clinical study assessing the efficacy and safety of neoadjuvant chemoradiotherapy combined with thymosin andtislelizumab in MSS/pMMR LARC. Stage II/III MSS/pMMR LARC patients (cT 3-4a N 0 M 0 and cT 1-4a N 1-2 M 0 ) with the tumor distal location ≤ 10 cm from anal verge at two centers in China were consecutively enrolled. Patients received chemoradiotherapy (50 Gy/25 f, 2 Gy/f, 5 days/week, 5 weeks; plus capecitabine 850-1000 mg/m 2 , bid, po, 5 days/week, day1-5), thymalfasin (4.8 mg, biw, ih, day 1 and day 4 from week 1-11) and three 21-day cycles tislelizumab (200 mg, iv.gtt, week 2, 5 and 8) as neoadjuvant therapy. Adjuvant therapies after neoadjuvant were nonuniformly specified and decided according to clinical experiences. The primary endpoint is the complete response (CR) rate, defined as the achievement of clinical complete response (cCR) after neoadjuvant therapy or pathological complete response (pCR) after total mesorectal excision (TME). Results: From Feb 2024 to Aug 2024, a total number of patients (n = 25) were enrolled and 3 patients were excluded because of T4b and dMMR. Finally, 2 patients were discontinued and 20 completed neoadjuvant therapy. The median age was 67.5 (from 36 to 74) years while the median tumor distal location was6.0 (from 3.5 to 8.5) cm. The CR, PD, and SD rate was 40.0% (8/20), 45.0% (9/20), and 15.0% (3/20) correspondingly, with the ORR rate of 85.0% (17/20). Grade 3 treatment-related adverse events (trAEs) including leukopenia and neutropenia were observed in 1 (5%) patient, while grade 1-2 trAEs were observed in 15(75.0%) patients. As for Dec 31, 2024, the EFS rate was 100% (20/20) with median follow-up time of 18.57 weeks (from 6.86 to 31.86). Conclusions: Neoadjuvant chemoradiotherapy plus thymalfasin and tislelizumab show promising anti-tumour activity in MSS/pMMR LARC patients, with manageable toxicities. This study suggests that such combination could be a promising therapeutic strategy for patients with MSS/pMMR LARC. Clinical trial information: NCT06056804 .

PURPOSE:The clinical benefit of incorporating oxaliplatin into conventional neoadjuvant chemoradiotherapy (nCRT) for patients with high-risk locally advanced rectal cancer (LARC) remains controversial. METHODS AND MATERIALS:This multicenter, open-label, randomized controlled trial enrolled 505 patients with high-risk LARC, defined by the presence of at least 1 of the following adverse features: clinical T4 stage, clinical N2 stage, high tumor grade, extramural vascular invasion, involvement of the mesorectal fascia, or perianal musculature involvement. Enrollment took place between August 2017 and April 2022. Patients were randomly assigned to receive long-course radiation therapy combined with a 3-cycle chemotherapy regimen of capecitabine and oxaliplatin (CapeOX group; n = 248) or capecitabine alone (Cape group; n = 257). The primary endpoint was 3-year disease-free survival (3y-DFS). RESULTS:Following nCRT, radical surgery was performed in 91.5% of the CapeOX group and 92.2% in the Cape group (P = .778). Pathologic complete response rates were comparable between the CapeOX and Cape groups (25.5% vs 25.3%; P = .954). A significantly greater proportion of patients in the CapeOX group achieved marked tumor regression (College of American Pathologists (CAP 0-1)) compared with the Cape group (58.6% vs 46.8%; P = .011). The incidence of grade 3 to 4 treatment-related toxicities was similar between the groups (CapeOX: 14.1% vs Cape: 9.3%; P = .095). After a median follow-up of 37 months, 3y-DFS and 3-year overall survival rates were comparable between the groups (both P > .050). Overall, patients who achieved CAP 0 to 1 had significantly better 3y-DFS than those with CAP 2 to 3 (89.0% vs 80.9%; P = .018). CONCLUSIONS:The addition of oxaliplatin to conventional nCRT may enhance pathologic tumor regression in patients with high-risk LARC without a significant increase in severe adverse events. However, this intensified 3-cycle chemotherapy regimen did not translate into a long-term survival benefit.

This multicenter, randomized, non-inferiority phase III trial (NCT03792100) aimed to evaluate the efficacy and safety of SmofKabiven®, a three-chamber parenteral nutrition (PN) emulsion in adult patients undergoing gastrointestinal surgery. Eligible participants were randomized to either SmofKabiven® group (SEG) (n = 135) or hospital-compounded PN group (HCG) (n = 134) for five consecutive postoperative days. The primary endpoint was the change in serum prealbumin levels from baseline to day 6, with a non-inferiority margin of -2.75 mg/dL. By day 6, change of serum prealbumin levels from baseline was 3.22 mg/dl in the SEG and 2.74 mg/dl in the HCG, with a difference of 0.48 mg/dl (95% confidence interval: -0.80 to 1.77), indicating comparable improvement in nutritional status. Linoleic acid decreased more with SEG than that with HCG (between-group difference: -7.84 mg/l, P = 0.0128), while arachidonic acid decreased more with HCG (between-group difference: 0.38 mg/l, P = 0.0025). Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were significantly higher with SEG (between-group difference: EPA, 0.48 mg/l, P < 0.0001; DHA, 0.64 mg/l, P < 0.0001, respectively), and taurine levels also increased significantly (between-group difference: 14.77 µM, P = 0.0217). Treatment-related adverse events were comparable in the two groups. SmofKabiven® was comparable to hospital-compounded PN in improving postoperative nutritional status and safety profile and its enrichment with omega-3 fatty acids and taurine may provide additional benefits.

Background:Sentinel lymph nodes and lymph node metastases in patients with colorectal cancer (CRC) seriously affect prognosis. In order to improve the accuracy of lymph node assessment during surgery, it is crucial to explore advanced imaging techniques. This study aimed to evaluate the diagnostic value of endoscopic ultrasound (EUS) versus indocyanine green (ICG) fluorescence imaging for sentinel lymph node metastasis (SLNM) and lymph node metastasis (LNM) in patients with CRC. Methods:A total of 120 patients with CRC admitted to our hospital from March 2022 to December 2023 were included in this retrospective study and, according to the detection method, they were divided into ICG group (ICG fluorescence imaging group, n=50) and control group (EUS group, n=70). The general data of patients, sensitivity, specificity, and accuracy of ICG imaging for the diagnosis of SLNM and LNM in patients with CRC were statistically compared between the two groups using gold standard postoperative pathology reports. Area under receiver operating characteristic (ROC) curve was used to analyze the diagnostic value of ICG fluorescence imaging for SLNM and LNM in patients with CRC. Results:For diagnosing SLNM in CRC patients, ICG fluorescence imaging achieved sensitivities, specificities, and accuracies of 94.44%, 93.75%, and 94.00%, respectively, significantly outperforming EUS, which achieved sensitivities, specificities, and accuracies of 40.74%, 69.77%, and 58.58% respectively. For LNM diagnosis, ICG fluorescence imaging showed sensitivities, specificities, and accuracies of 80.00%, 92.5%, and 90.00%, compared to 28.57%, 71.43%, and 62.86% for EUS. The area under curve (AUC) of ICG for LNM in patients with CRC was 0.932 with an optimal cut-off value of 0.77, achieving sensitivities and specificities of 95.45% and 81.82%. Conclusions:In the assessment of SLNM and LNM in patients with CRC, ICG fluorescence imaging is proven to be more valuable than EUS.

Introduction Anastomotic leakage (AL) is defined as the failure of complete healing or disruption of the anastomosis subsequent to rectal cancer surgery, resulting in the extravasation of intestinal contents into the intra-abdominal or pelvic cavity. It is a serious complication of rectal cancer surgery, accounting for a considerable increase in morbidity and mortality. The use of fluorescence imaging technology in surgery allows surgeons to better evaluate blood perfusion. However, the conclusions of some existing studies are not consistent, so a consensus on whether the near-infrared indocyanine green (NIR–ICG) imaging system can reduce the incidence of AL is needed.Methods This POSTER trial is designed as a multicentre, prospective, randomised controlled clinical study adhering to the “population, interventions, comparisons, outcomes (PICO)” principles. It is scheduled to take place from August 2019 to December 2024 across eight esteemed hospitals in China. The target population consists of patients diagnosed with rectal cancer through pathological confirmation, with tumours located≤10 cm from the anal verge, eligible for laparoscopic surgery. Enrolled patients will be randomly assigned to either the intervention group or the control group. The intervention group will receive intravenous injections of ICG twice, with intraoperative assessment of anastomotic blood flow using the near-infrared NIR–ICG system during total mesorectal excision (TME) surgery. Conversely, the control group will undergo conventional TME surgery without the use of the NIR-ICG system. A 30-day follow-up period postoperation will be conducted to monitor and evaluate occurrences of AL. The primary endpoint of this study is the incidence of AL within 30 days postsurgery in both groups. The primary outcome investigators will be blinded to the application of ICG angiography. Based on prior literature, we hypothesise an AL rate of 10.3% in the control group and 3% in the experimental group for this study. With a planned ratio of 2:1 between the number of cases in the experimental and control groups, and an expected 20% lost-to-follow-up rate, the initial estimated sample size for this study is 712, comprising 474 in the experimental group and 238 in the control group.Ethics and dissemination This study has been approved by Ethics committee of Beijing Friendship Hospital, Capital Medical University (approval number: 2019-P2-055-02). The results will be disseminated in major international conferences and peer-reviewed journals.Trial registration number NCT04012645.

e15612 Background: Thymalfasin, as an immunomodulator, can enhance the anti-tumor effects of T cells, NK cells, and macrophages. This study explored the efficacy and safety of a new adjuvant treatment regimen for rectal cancer, combining thymalfasin with chemoradiotherapy and the PD-1 inhibitor tislelizumab, and its impact on the immune microenvironment. Methods: This retrospective study enrolled 26 patients with locally advanced rectal cancer from March 2021 to December 2022. Thirteen patients received long-course concurrent chemoradiotherapy combined with concurrent tislelizumab treatment, and thirteen received thymalfasin combined with long-course chemoradiotherapy and concurrent tislelizumab treatment (radiotherapy: 50 Gy/25 f; capecitabine, 1000mg/m2, bid; tislelizumab: 200mg, every 21 days, 3 cycles; Thymalfasin: 1.6mg, biw). The postoperative pathological complete response rate (ypT0N0M0), tumor regression grade (AJCC 8th Version), and adverse event (CTCAE 4.0) incidence were assessed, along with changes in the immune microenvironment before and after treatment using multiplex immunofluorescence staining. Results: The pathological complete response rates observed postoperatively were 61.5% in the treatment group, compared to 38.5% in the control group. The distribution of tumor regression grades 0, 1, 2, and 3 was 69.2%, 15.4%, 15.4%, 0% in the treatment group respectively, and 38.5%, 38.5%, 7.7%, 15.4%, in the control group respectively. The adverse event rates reached 84.6% in the treatment group and 76.9% in the control group, with all events classified as either grade 1 or 2 according to the CTCAE 4.0. Significant reductions in CD4+PD1+ cell density (p < 0.001), CD8+PD1+ cell density (p = 0.024), CD68+ cell density (p = 0.007), the CD4/CD8 ratio (p < 0.001), and the CD68+CD86+/CD68+CD163+ ratio (p = 0.012) were demonstrated through multiplex immunofluorescence following neoadjuvant treatment. The treatment group exhibited significant decreases in CD8+PD1+ cell density (p = 0.025) and CD68+CD163+ cell density (p = 0.021) when compared to the control group. Conclusions: Thymalfasin combined with chemoradiotherapy and tislelizumab as a neoadjuvant treatment regimen for patients with locally advanced lower rectal cancer has shown favorable efficacy and safety. Neoadjuvant chemoradiotherapy combined with immunotherapy restored T cell function and reduced the proportion of tumor-associated macrophages, but macrophages polarized towards an M2-like phenotype. Thymalfasin may play a role by synergizing with the PD-1 inhibitor to restore cytotoxic T cell function and block macrophage polarization towards M2 cells. Clinical trial information: NCT06024356 .

Objective:To explore the practical application and clinical significance of modified grading system for Gastrointestinal Symptom Rating Scale (GSRS) scores in evaluating long-term postoperative gastrointestinal dysfunction (PGID) in patients after colon cancer surgery.Methods:A retrospective analysis was conducted on the case data of 122 patients who underwent right hemicolectomy for colorectal cancer at Beijing Friendship Hospital, Capital Medical University from September 2021 to September 2022. Among these patients, 69 were males (56.6%), and 53 were females (43.4%). The median age was 66.5 years, and the body mass index was (24.4±3.3) kg/m 2. The main observe indiator was GSRS scores of patients. The measurement data of normal distribution were represented as mean±standard deviation( ± s), and intergroup comparisons were conducted using ANOVA. The measurement data of non-normal distribution were expressed as the median (interquartile distance) [ M( Q1, Q3)], the Kruskal-Wallis H test was employed. Unordered count data comparisons were performed using the χ2 test, while comparisons for ordered count data between groups were conducted using the Kruskal-Wallis H test. GSRS scores were represented using density plots, and the scores were categorized into five symptom groups, presented using radar charts to illustrate the distribution of each symptom group. Results:Among the 122 patients, the most common long-term PGID syndromes was dyspepsia, followed by abdominal pain, diarrhea, and constipation. GSRS score data in the study population exhibited a nearly trimodal trend. Based on the overall data trend, the GSRS scale was refined, with cut-off values of 20 and 30, categorizing patients with right-sided colon cancer into low-risk, moderate-risk, and high-risk groups for quantifying the severity of long-term PGID. In terms of gender distribution, the differences among the three groups was statistically significant ( P=0.031), suggesting that males may be more susceptible to long-term PGID. However, there were no significant differences among the three groups concerning age, tumor location, surgical approach, anastomotic technique, lymph node dissection, pathological staging, adjuvant chemotherapy, and other factors. Conclusions:The modified grading system for GSRS scores aligns with the distribution characteristics of postoperative gastrointestinal function in colorectal cancer patients. It can quantify the risk of long-term PGID, allowing for a graded management approach to improve the postoperative quality of life for patients.

Background: This study aimed to assess the Caprini score in predicting venous thromboembolism (VTE) events and develop a risk assessment model to predict the occurrence of short-term VTE after colorectal cancer surgery. Methods: The study included 181 patients who underwent colorectal cancer surgery at Beijing Friendship Hospital, from October 2020 to May 2022. The results of the Caprini score 24 h after surgery were recorded to evaluate its predictive value. Multifactorial staging was used to determine independent risk factors for VTE, and nomogram models were constructed based on these factors. Sixty-one patients at Beijing Chaoyang Hospital were used for external validation. Results: The incidence of VTE after colorectal cancer was 17.6% in 32 patients. Age (odds ratio [OR] 1.106, 95% confidence interval [CI] 1.049–1.167, P < 0.001), sex (female) (OR 2.981, 95% CI 1.176–7.557, P = 0.021), and cardiovascular disease [CVD] (OR 5.611, 95% CI 2.043–15.413, P = 0.001) were independent risk factors for postoperative VTE. The nomogram model showed good predictive performance (area under the curve [AUC], 0.837 [95% CI, 0.762–0.917]; Nagelkerke R 2 , 0.347; Brier score, 0.106) compared with the Caprini score (AUC, 0.760 [95% CI, 0.674–0.847]; Nagelkerke R 2 , 0.104; Brier score, 0.131). The decision curve analysis showed that the nomogram model had a better net clinical benefit. Conclusions: The Caprini score is moderately efficient in predicting the occurrence of VTE after colorectal cancer surgery, and the 3-item nomogram model can be used as a predictive tool in VTE prevention decisions after colorectal cancer surgery.

Objective:To investigate the role of subcutaneous negative pressure drainage device in the prevention of surgical site infections (SSI) of superficial incisional in lower digestive tract open surgeries.Methods:Clinical data of 104 patients receiving open surgeries on lower digestive tract at Beijing Friendship Hospital, Capital Medical University from October 2018 to June 2020 was analyzed by a propensity score matching (PSM), and the clinical data of 104 patients receiving open surgeries on lower digestive tract at Beijing Friendship Hospital, Capital Medical University from February to December 2021 was analyzed by a randomized controlled trial (RCT). Chi-square tests were conducted to analyze the association of subcutaneous negative pressure drainage device with SSI of superficial incisional. Univariate and multivariate Logistic regression analysis were used to identify the risk factors for SSI in superficial incisions.Results:Patients with subcutaneous negative pressure drainage device encounter significantly less SSI of superficial incisional in both the PSM study ( P=0.007) and the RCT study ( P=0.049). In the PSM study, the independent risk factors for SSI of superficial incisional via univariate and multivariate Logistic regression analysis were absence of subcutaneous drainage ( Puni=0.012, Pmulti=0.009) and postoperative anastomosis leak ( Puni=0.054, Pmulti=0.034). In the RCT study, the independent risk factors for SSI of superficial incisional via univariate and multivariate Logistic regression analysis were absence of subcutaneous drainage ( Puni=0.061, Pmulti=0.017), eldly ( Puni=0.076, Pmulti=0.032), long incision ( Puni=0.078, Pmulti=0.040). Conclusion:Subcutaneous negative pressure drainage device can significantly reduce SSI of superficial incisional in lower digestive tract open surgeries.

Abstract Purpose As transanal total mesorectal excision (taTME) is performed worldwide, the optimization of existing training and guidance programs to enhance new taTME learners’ competence in performing this procedure is warranted. This study aimed to evaluate the taTME learning curve in patients with mid-low rectal cancer. Methods Patients who underwent taTME for mid-low rectal cancer between October 2015 and August 2021 at a single center were included. A cumulative sum (CUSUM) learning curve analysis was performed with the total operation time as the study outcome. The learning curve was analyzed using risk-adjusted CUSUM analysis, with postoperative complications and anastomotic leakage (AL) as outcomes. Results In total, 104 consecutive patients were included in this study. The CUSUM learning curve for total operative time started declining after 42 cases (309.1 ± 84.4 vs. 220.2 ± 46.4, P < 0.001). The risk-adjusted CUSUM (RA-CUSUM) learning curve for postoperative complications fluctuated in cases 44–75 and declined significantly after case 75. The RA-CUSUM learning curve for AL declined after 68 cases. Conclusions taTME had learning curves of 42, 75, and 68 cases for total operative time, postoperative complications, and AL, respectively. A surgeon may require 42 and 75 cases to achieve “proficiency” and “mastery” in taTME procedures, respectively.

Objective:To investigate the effect of obstruction on the prognosis and possible mechanisms in colorectal cancer patients.Methods:Among 1574 cases of colorectal cancer who were treated in Beijing Friendship Hospital, Capital Medical University from January 2003 to December. 2014, 194 cases had preoperative intestinal obstruction. Firstly, described the clinical characteristics of 194 patients with obstruction, then COX multivariate regression analysis was performed on the 1574 colorectal cancer cohort to confirm whether the preoperative obstruction was independent predictor for the overall survival. Finally, propensity score matching method was used to match obstruction and non-obstruction cases, then compared overall survival difference.Results:In 194 cases of obstructive colorectal cancer, 60.3% and 37.1% of the tumors were located in the left and right respectively. The 55.7% of the patients had tumors larger than 5 cm in diameter, the median survival time was 39.7 months (95% CI: 28.3-60.4). Multivariate COX analysis, after adjusted for related confounding factors, found that preoperative obstruction is still an independent risk factor for poor prognosis ( HR=1.41, 95% CI: 1.01-1.97). After propensity score matching, 140 and 560 patients were included in the obstructive group and the non-obstructive group. The two groups were more balanced in most baseline characteristics. The median survival time of the two groups was 42.4 and 116.3 months ( P<0.001), the overall survival of obstructive patients was significantly worse than that of non-obstructive patients. Conclusions:Preoperative obstruction is an independent risk factor for poor prognosis of colorectal cancer. This may be due to the difficulty of surgery and low radical cure rate for obstructive colorectal cancer.

目的 探索长程放化疗联合替雷利珠单克隆抗体作为错配修复基因蛋白无缺失型(pMMR)局部进展期中低位直肠癌病人新辅助治疗方案的安全性和有效性.方法 前瞻性分析2021年4月至2021年12月首都医科大学附属北京友谊医院11例临床分期为cT3-4N0M0或cTl-4N+M0接受全直肠系膜切除手术且术前行新辅助放化疗联合替雷利珠单克隆抗体治疗的pMMR中低位直肠癌病人临床资料.研究主要终点为病理完全缓解,同时分析药物不良反应发生率,手术安全性,术后并发症发生率以及病理组织学改变.结果 11例病人均完成放化疗,10例病人接受3次替雷利珠单克隆抗体治疗,1例接受2次替雷利珠单克隆抗体治疗.1例(9.1％)病人出现3级免疫性肠炎的不良反应.保肛手术率为100.0％.1例病人术后出现Clavien-Dindo Ⅱ级吻合口漏.所有病人肿瘤均为pMMR,共有6例(54.5％)病人达到病理完全缓解,3例(27.3％)达到主要病理缓解,客观缓解率达100.0％.6例病理完全缓解的病人中,有2例(18.2％)达到临床完全缓解.结论 pMMR局部进展期中低位直肠癌病人行长程放化疗联合靶向程序性细胞死亡受体-1(PD-l)抗体治疗具有良好的安全性和有效性,并不增加手术的并发症发生率,后续需要更大样本的研究进行进一步的验证.

目的 探究经肛全直肠系膜切除(transanal total mesorectal excision,taTME)术后吻合口失败的发生率,并确定其危险因素.方法 分析首都医科大学附属北京友谊医院2016年11月至2021年10月期间前瞻性收集的88例连续性接受taT M E手术并行一期吻合的直肠癌病人的临床资料.主要研究终点为吻合口失败,包括早期和晚期吻合口漏、盆腔脓肿、吻合口瘘管形成、慢性窦道形成及吻合口狭窄.计数资料比较采用χ2检验或Fisher确切概率法来探究组间基线差异,计量资料比较采用Mann-Whitney U检验来探究组间基线差异.使用二元Logistic模型确定吻合口失败的独立危险因素.结果 88例接受taTME手术的病人中发生吻合口失败19例(21.6％).总的吻合口漏发生率为18.2％(16/88),A级7例,B级8例,C级1例.早期(术后≤30 d)吻合漏13例(14.8％),其中3例(3.4％)病人出院后被诊断;晚期(术后>30 d)吻合口漏3例(3.4％).5例病人因吻合口漏再次入院治疗,4例病人形成慢性盆腔脓肿.吻合口狭窄的发生率为11.4％(10/88),其中7例病人同时被诊断为吻合口漏.未发现病人有吻合口瘘管及慢性窦道形成.单因素分析结果显示,吸烟、美国麻醉医师协会分级≥ Ⅲ级和低位肿瘤与taT M E术后吻合口失败的发生显著相关;多因素分析显示,糖尿病是吻合口失败的独立危险因素.结论 根据吻合失败危险因素,对于高风险病人个体化制定前期管理、术中决策以及术后治疗方案,以减少和减轻吻合口相关并发症的发生.

Transanal total mesorectal excision (taTME) is a promising surgical procedure for middle and low rectal cancer; however, it is linked to significant morbidity. This study aimed to determine the incidence of postoperative surgical complications and anastomotic leakage following taTME and to identify their associated risk factors. The prospective clinical data of 114 patients, who underwent taTME and primary anastomosis for mid-low rectal cancer between November 2016 and June 2022, were retrospectively analyzed. Univariate and multivariate analyses were performed to identify clinical characteristics and risk factors for predicting surgical complications and anastomotic leakage. Surgical complications occurred in 40 (35.1%) patients within the first 30 days following surgery. Based on the Clavien–Dindo classification, minor complications (Clavien–Dindo grades I + II) accounted for 30.7%, while major complications (Clavien–Dindo grades III + IV) accounted for only 4.4%. None of the patients died within 30 days. The incidence of anastomotic leakage was 15.8%: 4.4% as grade A (5 cases), 9.6% as grade B (11 cases), and 1.8% as grade C (2 cases). Preoperative T3-4 was identified as an independent risk factor for surgical complications (p = 0.031) by multivariate analysis. American Society of Anesthesiology score ≥ 3 (P = 0.021) and incomplete total mesorectal excision specimens (P = 0.030) were significantly associated with the risk of anastomotic leakage. In this study, the incidence of surgical complications and anastomotic leakage in taTME aligned with previously reported rates. Preoperative T3-4 was significantly associated with surgical complications. American Society of Anesthesiology score ≥ 3 and incomplete TME specimens independently increased the risk of anastomotic leakage.

PurposeSurgical complications following laparoscopic rectal cancer surgery remain a major clinical problem. The prognostic nutritional index (PNI) is reportedly associated with postoperative outcomes. We aimed to evaluate the correlation between PNI and short-term surgical complications in patients with rectal cancer after laparoscopic surgery.MethodsThe prospective clinical data of 225 patients with rectal cancer receiving laparoscopic surgery between January 2021 and April 2022 were retrospectively analyzed. The cut-off values and diagnostic accuracy of PNI preoperatively and on postoperative day (POD) 1 were determined using receiver operating characteristic (ROC) curves. Univariate and multivariate analyses were performed to identify clinical characteristics and risk factors for surgical complications.ResultsIn total, 81 (36.0%) patients developed surgical complications. The optimal cut-off value for preoperative PNI was 40.15, and that for PNI on POD 1 was 35.28. The DeLong test found no statistically between–group difference in the area under the ROC curve (P = 0.598). Multivariate analysis identified that a preoperative PNI ≤40.15 [odds ratio (OR): 2.856, 95% confidence interval (CI): 1.287–6.341, P = 0.010] and PNI on POD 1 ≤35.28 (OR: 2.773, 95% CI: 1.533–5.016, P = 0.001) were independent risk factors for surgical complications. Patients with a preoperative PNI ≤40.15 or PNI on POD 1 ≤35.28 were more likely to have surgical complications after laparoscopic surgery for rectal cancer (61.1% vs. 31.2%, P = 0.001; 53.0% vs. 28.9%, P = 0.001).ConclusionPreoperative and POD 1 PNI were independent predictors of short-term surgical complications after laparoscopic surgery for rectal cancer.

Immunotherapies, especially the programmed cell death 1/programmed cell death ligand 1 (PD-1/PD-L1) inhibitors, have revolutionized the therapeutic strategies of various cancers. As for colorectal cancer (CRC), the current clinical application of PD-1/PD-L1 inhibitors are mainly used according to the mutation pattern, which is categorized into deficient mismatch repair (dMMR)/high levels of microsatellite instability (MSI-H) and proficient mismatch repair (pMMR), or non-high levels of microsatellite instability (non-MSI-H). PD-1/PD-L1 inhibitors have been proven to have favorable outcomes against dMMR/MSI-H CRC because of more T-cell infiltration into tumor tissues. Nevertheless, the effectiveness of PD-1/PD-L1 inhibitors in pMMR/non-MSI-H CRC is still uncertain. Because of the quite-lower proportion of dMMR/MSI-H in CRC, PD-1/PD-L1 inhibitors have been reported to combine with other antitumor treatments including chemotherapy, radiotherapy, and targeted therapy for better therapeutic effect in recent clinical trials. Neoadjuvant therapy, mainly including chemotherapy and radiotherapy, not only can reduce clinical stage but also benefit from local control, which can improve clinical symptoms and the quality of life. Adding immunotherapy into neoadjuvant therapy may change the treatment strategy of primary resectable or some metastatic CRC. In this review, we focus on the development of neoadjuvant anti-PD-1/PD-L1 therapy and discuss the future perspectives in CRC.

Background Prediction and management of short-term postoperative complications in patients with colorectal cancer are essential in postoperative rehabilitation. Through CT scan images, we can easily measure some parameters of abdomen anatomic characteristics. This study aimed to assess whether there is a relationship between the abdomen anatomic characteristics and short-term postoperative complications. Materials and methods We conducted a retrospective study. Eighty patients in each complication group and non-complication group were recruited with propensity score match. Demographics, perioperative laboratory results and surgical information were collected and compared between groups with univariate analysis. Significant elements were brought into subsequent logistic regression analysis and ROC analysis for further identification. Results Univariate analysis showed that preoperative white blood cells, preoperative neutrophil counts, rectus abdominis thickness (RAT), subcutaneous fat thickness (SFT), and abdomen depth (AD) were significantly different between the complication group and non-complication group. Logistic regression analysis demonstrated that higher RAT ( p = 0.002), SFT ( p < 0.001) and AD ( p < 0.001) independently predicted the incidence of short-term postoperative complications. Conclusions In this study on patients undergoing radical resection of colorectal cancer, abdomen anatomic characteristics including higher RAT, SFT and AD are associated with an increased risk of short-term postoperative complications.

目的:探讨分析开腹消化道手术后发生延迟性肠麻痹(PPOI)对术后住院时间、医疗花费等的不良影响程度。方法:回顾性分析2016年10月—2018年11月首都医科大学北京友谊医院普外科行开腹消化道手术的126例消化道肿瘤患者资料，根据奥克兰大学提出的PPOI诊断标准，将纳入患者分为PPOI组( n＝14)和非PPOI组( n＝112)。选取术后并发症、术后住院时间以及住院期间医疗花费为研究终点指标。采用 t检验或者Fisher精确检验比较两组差异，并通过回归分析探讨PPOI对住院时间、医疗花费的独立影响。 结果:本研究队列PPOI发病率为11.1%。PPOI组总并发症发生率升高(64.29%比38.39%， P＝0.08)。PPOI组患者术后平均住院时间较非PPOI组较长[(21.21±14.83) d比(13.98±14.21) d， P＝0.070]。调整各种可能的混杂因素，影响住院时间的PPOI回归系数beta(95% CI)为[-0.43(-7.16，6.3)， P＝0.90]。PPOI组患者平均医疗花费较非PPOI组升高[(104 389.64±52 427.66)元比(79 111.41±50 832.29)元， P＝0.070]。调整各种可能的混杂因素，影响医疗花费的PPOI回归系数beta(95% CI)为[-134.12(-21656.85，21388.62)， P＝0.99]。 结论:延迟性术后肠麻痹导致术后康复的延迟，与术后并发症发生增加相关，增加住院时间和医疗花费。但尚需大样本数据进一步证实。

Objective:To investigate the relationship between systematic immune-inflamma-tion index(SII) and clinicopathological characteristics for colorectal cancer.Methods:The retrospec-tive cohort study was conducted. The clinicopathological data of 513 patients with colorectal cancer who were admitted to the Beijing Friendship Hospital of Capital Medical University from February 2019 to May 2021 were collected. There were 311 males and 202 females, aged (64±12)years. Observation indicators: (1) SII of colorectal cancer and relationship between SII and clinicopatholo-gical characteristics; (2) influencing factors for SII in colorectal cancer patients. According to the median of SII as the cutoff value, the patients were divided into high SII and low SII patients. Measurement data with normal distribution were represented as Mean± SD, and comparison between groups was analyzed using the t test. Count data were represented as absolute numbers or percen-tages, and comparison between groups was conducted using the chi-square test. Measurement data with skewed distribution were represented as M( P25, P75), and comparison between groups was analyzed using the non-parameter rank sum test. Comparison of ordinal data was analyzed using the Mann-Whitney U non-parameter test. Variables with statistically significant differences between groups were included for further analysis. Pearson correlation coefficient analysis was used for continuous data, and Wilcoxon or Kruskal-Willas analysis was used for categorical data and Bonferroni correction was performed. Univariate and multivariate linear regression analyses were conducted. Results:(1) SII of colorectal cancer and relationship between SII and clinicopathological charac-teristics: the SII of 513 patients was 355(253,507). Taking the median SII 355 as the cutoff value, 257 of 513 patients with SII>355 had high SII and 256 cases with SII≤355 had low SII. Of high SII patients, the Karnofsky performance status(KPS) score, preoperative albumin(Alb), CA125, cases with tumor located at left or right hemicolon, tumor diameter, cases with laparoscopic assisted surgery or laparotomy (surgical approach), cases in stage T0, T1, T2, T3, T4 (pathological T staging), cases in stage Ⅰ, Ⅱ, Ⅲ, Ⅳ (pathological TNM staging) were 87±17, (37±5)g/L, 8.80 U/mL(5.90 U/mL, 14.15 U/mL), 174, 83, (5.2±2.8)cm, 208, 44, 5, 19, 25, 131, 63, 34, 98, 94, 14. The above indicators of low SII patients were 91±13, (38±4)g/L, 7.20 U/mL(5.40 U/mL, 10.03 U/mL), 200, 56, (4.0±1.9)cm, 221, 24, 8, 39, 35, 118, 45, 61, 84, 79, 12. There were significant differences in above indicators between the two groups ( t=-2.770, -3.211, Z=-3.799, χ2=7.050, t=5.324, χ2=6.179, Z=-3.390, -2.227, P<0.05). Results of Pearson correlation coefficient analysis showed that SII was positively correlated with the tumor diameter ( r=0.390, P<0.05), and negatively correlated with preoperative Alb ( r=-0.200, P<0.05). Results of Wilcoxon analysis showed that SII was 447(311,720), 352(251,493) in patients with tumor located at right hemicolon and left hemicolon, 439(284,640), 345(243,481) in patients undergoing laparotomy and laparoscopic assisted surgery, respectively. There were signi-ficant differences in SII between patients with tumor located at right and left hemicolon,between patients undergoing laparotomy and laparoscopic assisted surgery ( P<0.05). Results of Kruskal-Willas analy-sis showed that SII was 289(201,463), 296(210,398), 329(252,446), 369(265,505), 434(274,631) in patients with pathological T staging as stage T0, stage T1, stage T2, stage T3, stage T4, respectively, and 307(226,400), 380(260,503), 381(272,563), 376(273,634) in patients with patho-logical TNM staging as stage Ⅰ, stage Ⅱ, stage Ⅲ, stage Ⅳ, respectively. There were significant differences in SII between patients with different pathological T staging and between patients with different pathological TNM staging ( P<0.05). (2) Influencing factors for SII in colorectal cancer patients: results of univariate analysis showed that KPS score, preoperative Alb, CA125, tumor location, tumor diameter, patholo-gical N staging, pathological TNM staging were related factors for SII in colorectal cancer patients ( Beta=-3.5, -15.8, 3.7, 106.3, 51.8, 115.1, 104.7, 141.2,95% confidence interval as -5.7 to -1.3, -22.6 to -9.1, 1.8 to 5.5,34.6 to 177.9, 38.5 to 65.2, 40.5 to 189.7, 11.2 to 198.2, 46.9 to 235.9, P<0.05). Multivariate analysis showed that tumor location and tumor diameter were independent influencing factors for SII in colorectal cancer patients ( Beta=79.5, 42.5, 95% confidence interval as 8.4 to 150.7, 26.6 to 58.4, P<0.05). Conclusions:The SII is correlated with tumor location, tumor diameter, preoperative Alb, pathological T staging, pathological TNM staging. Preoperative hypoproteinemia indicates a high SII score. The longer of tumor diameter, right hemicolon tumor and high TNM staging indicate the more serious immune-inflammatory imbalance. Tumor location and tumor diameter are independent influencing factors for SII in colorectal cancer patients.