AimDifferent degrees of defecation dysfunction emerge after sphincter-saving surgery. It is essential to implement dietary management interventions to manage defecation dysfunction. This scoping review aimed to map the existing literature on nurse-led dietary modification recommendations for defecation dysfunction management and highlight any gaps in the literature.DesignA systematic scoping review model was applied.MethodsFour comprehensive databases were searched (01 November 2014 to 26 May 2025) and records were independently screened by two researchers using eligibility criteria. Articles were included if they were published in a peer-reviewed journal, employed quantitative research designs, and described a nurse-led dietary modification intervention for patients after sphincter-saving surgery. Data from the included studies were charted using a purpose-designed template, and data charting included participant characteristics, study methodology, information about the nurse-led dietary modification intervention, and the effectiveness of the intervention.ResultsFive publications met the study inclusion criteria: four randomized controlled pilot studies and one population-based, before-and-after pilot study. The studies varied in terms of intervention components, timing of delivery, and delivery mode. Two studies specifically focused on the effects of dietary modification programs, while the other three studies listed dietary management as one of the comprehensive nurse-led interventions. Nurse-led dietary recommendations included dietary fiber management, a diet diary, symptom-specific dietary modifications, and fiber supplement usage.Patient or public contributionNurse-led dietary modification recommendations had different degrees of effectiveness in improving defecation dysfunction in this review. Further research regarding remote and precise nurse-led dietary management is warranted, and a more standardized, evidence-based nurse-led dietary modification program could be provided for clinical nursing care.Systematic Review RegistrationPROSPERO ChiCTR2400082167.

Objectives This pilot cross-sectional observational study explored how dietary intake affects post-sphincter-preserving surgery defecation dysfunction via regulating intestinal flora. Methods: The study enrolled 81 patients at an East China tertiary hospital (Sep–Dec 2024). General/clinical questionnaires, LARS score, simplified FFQ were used to collect data on demographics, defecation dysfunction and dietary intake; 16S rRNA sequencing analyzed stool samples’ gut microbiota. PCA grouped defecation dysfunction into frequency-dominant and incontinence-dominant subtypes, and parallel mediation models examined diet-microbiota-dysfunction mediating effects. Results: The more severe frequency-dominant symptoms were correlated with lower gut microbiota alpha-diversity (Chao1, Faith_pd, Observed_species) and reduced Synergistota enterotype(P = 0.020). Egg-based foods were found to reduce Fusobacteriota abundance, thereby mediating the control of post-surgery defecation dysfunction (especially defecation frequency) within 6 months(-0.019(-0.368,-0.036)). Conclusions: This study clarifies the gut microbiota-mediated mechanism of dietary effects on defecation dysfunction, providing a theoretical basis for scientific dietary management, and suggests further research on postoperative diet-bowel symptom associations and microbiota-dysfunction causality to validate these pilot findings.

PURPOSE:Neoadjuvant chemoradiotherapy (nCRT) is the standard treatment for patients with locally advanced rectal cancer (LARC); however, pathologic complete response (pCR) rates and long-term outcomes remain suboptimal. This study evaluated the safety and efficacy of atezolizumab (Atezo) with or without tiragolumab (Tira) after nCRT in patients with LARC. METHODS:This randomized, parallel-group, phase II study included a safety run-in and a subsequent randomized phase. Eligible patients (cT3N+M0 or cT4NanyM0) received long-course nCRT (45-50.4 Gy in 25-28 fractions with concurrent capecitabine), followed by three 21-day cycles of Atezo (1,200 mg once on day 1 of each cycle), either combined with Tira (600 mg; Atezo + Tira arm) or alone (Atezo arm). Radical surgery was performed 2 weeks after final dose. The primary end point was pCR rate. Secondary end points included 1-year event-free survival (EFS) rate and safety. Outcomes were compared with historical controls. RESULTS:At data cutoff (January 6, 2025), three patients were enrolled in safety run-in and received Atezo + Tira. In randomized phase, 55 patients were assigned 1:1 to Atezo + Tira arm (n = 28) or Atezo arm (n = 27). pCR rate was 35.7% (95% CI, 18.6 to 55.9; v historical control [15%] P = .002) in Atezo + Tira arm and 22.2% (95% CI, 8.6 to 42.3; v historical control [15%] P = .293) in Atezo arm. After a median follow-up of 21.55 months (range, 20.67-22.24), 1-year EFS rates were 96.3% (95% CI, 76.5 to 99.5) in Atezo + Tira arm and 92.1% (95% CI, 72.1 to 98.0) in Atezo arm. Grade 3 to 4 treatment-related adverse events occurred in 31.0% and 26.9%. Grade 3 to 4 AEs related to Atezo or Tira were 10.3% and 11.5%, respectively. No treatment-emergent deaths were reported. CONCLUSION:In patients with LARC, Atezo + Tira after nCRT statistically improved the pCR rate compared with historical controls, with an acceptable safety profile.

Robotic surgery has become a new trend in minimally invasive surgery. Robotic surgery for rectal cancer has developed rapidly in the past decade. Many studies show that robotic surgery can reduce surgical trauma, promote postoperative recovery, and protect pelvic nerve and organ function, compared with conventional laparoscopic surgery. In terms of tumor radicality for rectal cancer, there is evidence that robotic surgery has advantages, although these are not yet sufficient. Similarly, in long-term oncological outcomes, robotic surgery shows promise, but the evidence remains insufficient. The learning curves, surgeons’ fatigue, and the cost effectiveness of robotic surgery for rectal cancer also deserve attention. New technologies such as trans-anal total mesorectal excision and remote robotic surgery are gradually maturing and may bring significant changes to surgical concepts. More technological advances and clinical evidence for robotic surgery in patients with preoperative immunotherapy are necessary. Artificial intelligence also brings progress and new prospects to robotic surgery. This review briefly summarizes the current status and future directions of robotic surgery for rectal cancer.

BACKGROUND Current guidelines have not reached consensus on hemostatic management for large polyps (10-20 mm) removed by cold snare polypectomy (CSP). In light of the low complication rate of CSP and the potential hypercoagulability in colorectal cancer (CRC) patients, prophylactic hemoclip use after CSP for polyps >= 10 mm appears unlikely to reduce bleeding risk in patients with suspected colorectal cancer. AIM To evaluate the necessity of prophylactic hemoclip use after CSP for polyps >= 10 mm in patients with CRC. METHODS This prospective cohort study with a historical control was conducted in Zhongshan Hospital. A total of 110 patients undergoing CSP without prophylactic hemoclip closure were prospectively enrolled (November 2022-October 2023), while 94 patients who received prophylactic hemoclip closure (November 2021-November 2022) served as controls. Inverse probability of treatment weighting (IPTW) was applied to balance baseline confounders. Rare bleeding events were analyzed using Firth penalized-likelihood logistic regression, and quantile regression was used to evaluate procedural time and cost. RESULTS Before weighting, the non-clipping group showed significantly shorter procedural time (25.31 +/- 16.75 minutes vs 29.31 +/- 14.97 minutes; Z = 2.49, P = 0.01) and lower cost (4604.75 +/- 2564.28 CNY vs 4915.55 +/- 2327.80 CNY; Z = 2.06, P = 0.04) compared to the control group. After IPTW adjustment, no statistically significant differences were found in intraoperative or postoperative bleeding rates between the groups. Quantile regression indicated no significant difference in operative time across quantiles (all P > 0.05). However, a significant association was observed at the 0.25 quantile with cost (coefficient =-382.282, P = 0.035), suggesting non-use of clips was associated with reduced cost in the lower-cost subgroup. CONCLUSION In this cohort, prophylactic hemoclip use does not significantly alter bleeding risk or procedural time for CSP of polyps >= 10 mm, but its utilization strategy may impact cost containment.

To develop a postoperative risk stratification model integrating baseline T2 mapping and histopathologic factors for predicting disease-free survival (DFS) in patients with locally advanced non-mucinous rectal adenocarcinoma after neoadjuvant chemoradiotherapy (NCRT) and surgery. This retrospective study included 116 patients with non-mucinous rectal adenocarcinoma who underwent NCRT followed by surgery. Baseline T2 values and apparent diffusion coefficient (ADC) values were measured. Prognostic factors for DFS were assessed using Cox proportional hazards regression. Given the limited number of DFS events, the multivariable model size was prespecified, with baseline pretreatment T2 forced into the model. To assess the incremental prognostic value of T2, a clinicopathologic model was compared with a full model additionally including baseline pretreatment T2. The full model was refitted in the entire cohort and presented as a nomogram. Internal validation was performed using 1000 bootstrap resamples. Model performance was assessed by Harrell’s concordance index (C-index), bootstrap-estimated calibration slope, bootstrap calibration plots, time-dependent receiver operating characteristic analysis, and decision curve analysis. During a median follow-up of 51 months after surgery, 35 of 116 patients (30.2

While physical activity, sedentary behavior, and sleep have individually been linked to long-term outcomes in cancer survivors, few studies have evaluated their synergistic effects across a full 24-h period. This study aimed to examine the association between adherence to the Canadian 24-Hour Movement Guidelines and mortality risk in a nationally representative sample of US cancer survivors. Data from 2551 cancer survivors participating in the 2007–2018 National Health and Nutrition Examination Survey were analyzed. Adherence to the 24-Hour Movement Guidelines for aerobic physical activity, sedentary behavior, and sleep was summed to categorize participants into four groups. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95

Neoadjuvant therapy is expanding rapidly across tumor types, yet efficacy endpoints remain anchored in subjective tumor regression grading systems developed for cytotoxic therapy. We argue that post-treatment histopathology should evolve toward quantitative and biologically interpretable metrics integrating tumor burden, immune contexture, and spatial organization. We outline a validation pathway distinguishing prognostic biomarkers from true surrogate endpoints and propose a tumor- and regimen-aware framework for developing reproducible histologic endpoints in neoadjuvant oncology.

Introduction Given the metabolic vulnerability of colorectal cancer (CRC) cells, periodic fasting-mimicking diets (FMDs) have emerged as a promising dietary strategy for improving clinical outcomes. Although preclinical studies have suggested that FMDs may suppress tumour growth and early-phase clinical trials have demonstrated their safety and feasibility, evidence regarding their effects on long-term survival outcomes in CRC remains limited because of certain constraints in patient cohorts and study designs.Method and analysis This multicentre, prospective, randomised controlled trial will be conducted at six tertiary comprehensive hospitals in China. It is anticipated that 602 eligible participants with clinical stage III CRC will be recruited. Participants will be randomly assigned at a 1:1 ratio to either the FMD group or the control group. After the 4-month dietary intervention, participants will continue to be followed up for 3 years. The primary outcome is 3-year disease-free survival. Participant enrolment began in June 2022, and the study is expected to be completed in December 2027.Ethics and dissemination The study protocol was approved by the ethics committees of Zhongshan Hospital, Fudan University and other participating centres. The findings of this study will be disseminated through publication in peer-reviewed journals and presentation at academic conferences.Trial registration number NCT05384444.

In the past 5 years, clinical trials on immune checkpoint inhibitors (ICIs) for the treatment of locally advanced rectal cancer (LARC) have flourished globally, and China has become one of the leading regions in this field. In response to the breakthrough progress and accumulation of evidence from key clinical trials, the Chinese Society of Colorectal Surgery has recognised the need for updated consensus guidance on the development of perioperative and organ-preserving treatment strategies for LARC. This expert consensus guidance provided unified standards for the indications, medication regimens, efficacy evaluations and follow-up of ICIs in this population, with a focus mainly on perioperative management and organ-sparing strategies. The diagnostic part of this consensus guidance is based on the internationally recognised definition of mismatch repair/microsatellite instability detection and emphasises the importance of multidisciplinary teams in treatment decision-making. In terms of treatment, based on the results of key trials that have changed clinical practice in the past 5 years, this expert consensus provides graded recommendations for the duration of preoperative immunotherapy and the necessity of postoperative adjuvant therapy, local resection and organ preservation strategies. Moreover, we refined the management process for the safety of perioperative immunotherapy. This document aims to provide a reference for surgeons; internal medicine, radiation therapy, pathology and imaging physicians; patients and nursing staff involved in the treatment of LARC, as well as health policy makers.

Abstract The liver is the primary target organ for hematogenous metastasis of colorectal cancer, and colorectal cancer liver metastasis is one of the key and challenging aspects in its treatment. In order to improve the diagnosis and comprehensive treatment of colorectal cancer liver metastasis, the guideline development group has summarized advanced experiences and the latest achievements from both domestic and international sources, and has once again revised and updated the Guideline for the diagnosis and comprehensive treatment of colorectal cancer liver metastases (2025 edition) to continuously provide guidance and reference for clinical practice in this field.

LBA3563 Background: The optimal second-line treatment for metastatic colorectal cancer (mCRC) after failure of oxaliplatin-based chemotherapy therapy remains an area of active research, while bevacizumab combined with chemotherapy is a standard option. Fruquintinib (Fru) is a highly selective and potent oral tyrosine kinase inhibitor of VEGFR 1, 2, and 3. This study aimed to compare the efficacy and safety of fruquintinib combined with chemotherapy versus bevacizumab combined with chemotherapy as second-line treatment for mCRC. Methods: This was a non-inferiority trial conducted across 12 hospitals and cancer centers in China. Patients with mCRC who had progressed on fluoropyrimidine and oxaliplatin-based first-line chemotherapy therapy were randomly assigned (1:1) to receive either Fru (4 mg orally, once daily for 3 weeks on/1 week off) plus FOLFIRI, or bevacizumab (Bev) (5 mg/kg intravenous, every 2 weeks) plus FOLFIRI. Randomization was stratified by primary tumor location and RAS/BRAF status. During combination therapy, pts who achieve disease control after 4-6 months of treatment proceeded to maintenance therapy, receiving either fruquintinib combined with capecitabine or bevacizumab combined with capecitabine. The primary endpoint was progression-free survival (PFS). Final analysis occurred after either 97 PFS events or after the last patient had completed 12 months of follow-up, whichever occurred first. The non-inferiority upper margin of HR was 1.33. Results: Between Jul 13, 2023, and Mar 4, 2025, 122 pts were enrolled and randomly assigned to the Fru group (n=60) or the Bev group (n=62). The median age was 59.0 (IQR 54-69) and 60.0 (IQR 51-70) years, 45 (75%) and 48 (77%) had left-sided tumors, 36 (60%) and 36 (58%) were RAS/BRAF mutant, respectively. At data cut-off (Feb 28, 2026), the median PFS of the Fru group was non-inferior to the Bev group, whether in the Intention to Treat Population (ITT) (9.40 vs 7.39 months, hazard ratio [HR]=0.806 [95% CI 0.522–1.244, 80% CI 0.607-1.07]; p=0.33) or the per-protocol set (PPS) (9.49 vs 7.85 months, HR=0.848 [95% CI 0.542–1.326, 80% CI 0.633-1.136]; p=0.469). In the subgroup analysis , the Fru group showed longer PFS in prior never used VEGF inhibitor pts (10.6 vs 8.5 months, HR=0.94, 95% CI 0.54-1.62), and pts without liver metastasis (14.5 vs 9.9 months, HR=0.97, 95% CI 0.43-2.22) compared to the Bev group. The objective response rate was 35.0% with Fru vs 22.6% with Bev group. Any-grade treatment-emergent adverse events (TEAEs) occurred in 100.0% (Grade ≥3, 28.1%) of the Fru group and 93.2% (Grade ≥3, 28.8%) of the Bev group. Conclusions: Fruquintinib combined with FOLFIRI demonstrated non-inferiority in PFS compared with bevacizumab combined with FOLFIRI as a second-line treatment for mCRC, with a manageable safety profile. Clinical trial information: NCT05555901 .

Robot surgery is an important trend in contemporary colorectal cancer surgical treatment. The Robotic Surgery Group, Colorectal Cancer Committee of Chinese Medical Doctor Association organized experts in relevant fields across the country to update and revise the application standards of robotic colorectal cancer surgery based on the Expert consensus on robotic surgery for colorectal cancer (2015 edition) and the revised version in 2020, in accordance with the development of robotic surgery concepts, technologies, and equipment in recent years, in order to promote the application and promotion of robotic surgery.

INTRODUCTION:Clinical management of RAS wild-type colorectal cancer liver metastases (CRLM) remains challenging because many patients exhibit primary resistance to anti-EGFR therapy. Our research centered on the development of a multi-omics deep learning framework, designed to bridge the gap between complex multi-omics data and the necessity for precise therapeutic response forecasting in this specific cohort. MATERIALS AND METHODS:Patient cohorts receiving cetuximab from a prior investigation (PMID: 30305811) constituted the training and testing sets. For external validation, an independent cohort of consecutive patients with RAS wild-type CRLM patients was prospectively enrolled from other institutions between January and December 2018. Utilizing the PyTorch deep learning framework, we initially developed individual radiomic and genetic signatures. Subsequently, computed tomography (CT) images and genetic data were processed through pre-trained ResNet18 and Random Forest models, respectively. The final classification probability of the integrated model was calculated by weighted summation of the output probabilities from the two models, with weights of 3 and 7, respectively. RESULTS:The developed signature demonstrated predictive capability for cetuximab sensitivity, with area under the curve (AUC) values of 0.75 for the radiomic model, 0.81 for the genetic model, and 0.86 for the combined model. In contrast, it did not predict response to chemotherapy (fusion signature AUC: 0.54). Within cohorts treated with cetuximab, the fusion signature proved superior to established biomarkers for identifying treatment-sensitive cases (hazard ratio (HR), 17.9; 95% confidence interval (CI), 3.22-154.31; P = 0.003). Furthermore, it showed a significant correlation with progression-free survival (PFS), with a median PFS of 9.0 versus 5.0 months (HR, 0.44; 95% CI, 0.20-0.99; P = 0.047). DISCUSSION:The proposed multi-omics signature showed a promising ability to identify RAS wild-type CRLM patients more likely to benefit from anti-EGFR therapy using routinely available pretreatment CT and genomic data. Although the external validation cohort was relatively small and further validation is still needed, it may provide a practical tool for early treatment stratification and individualized decision-making. CONCLUSIONS:The developed multi-omics signature demonstrated promising performance in predicting sensitivity to anti-EGFR therapy and may help refine survival-based treatment stratification in patients with RAS wild-type CRLM.

Immunotherapy has demonstrated efficacy in colorectal cancer (CRC), primarily benefiting the microsatellite instability-high (MSI-H) population, which comprises approximately 15% of cases. However, it remains unclear whether any patients with microsatellite stability (MSS) CRC will benefit from immunotherapy. This study aims to identify a novel subtype within MSS CRC that may respond to immunotherapy. Single-cell RNA-sequencing data were utilized to define immune cell signatures in MSS CRC. Using these signatures, we developed a classification panel by integrating data from five independent transcriptomic databases. Spatial transcriptomics was employed to analyze gene panel localization. Multiple immunofluorescence assays were conducted to explore the tumor microenvironment. Additionally, organoids co-cultured with paired peripheral blood mononuclear cells were used to assess immunotherapy responsiveness. Signatures of multiple immune cell types were identified from the single-cell RNA-sequencing database for MSS CRC. Based on these signatures, MSS CRC was classified into two distinct subtypes: "immune-enriched" and "immune-desert", each exhibiting unique prognostic and tumor microenvironment profiles. The classification panel achieved an area under the curve greater than 0.9 across five independent databases. In a cohort of 223 patients, survival analysis indicated that "immune-enriched" patients had a significantly better prognosis. Multiple immunofluorescence assays revealed higher immune cell infiltration in these patients. When treated with anti-PD-1 antibodies, "immune-enriched" organoids in peripheral blood mononuclear cell co-culture models showed increased sensitivity. In conclusion, we have developed a panel that identifies a novel MSS CRC subtype with a tumor microenvironment resembling that of MSI-H CRC patients, demonstrating potential responsiveness to immunotherapy.

Deep learning (DL) approaches leveraging multi-parametric magnetic resonance imaging (mpMRI) hold significant promise for the preoperative assessment of rectal cancer T-stage. In this study, we investigate whether a mpMRI fusion-based DL model can effectively evaluate the T-stage of rectal cancer. To enable robust development and comprehensive evaluation of an automated T-staging system, we assembled the largest mpMRI cohort to date, comprising 756 patients from three institutions with nine distinct imaging sequences. We introduce a multi-view multi-parametric (MVMP) MRI fusion model for this purpose. The strategy for effective sequence fusion involves grouping different MRI sequences based on scanning directions and integrating features from each group using an attention module. During evaluations, the MVMP model achieves performance comparable to that of two radiologists in both the internal test cohort (AUC: 0.84 vs. 0.79 vs. 0.79) and the external test cohort (AUC: 0.83 vs. 0.81 vs. 0.75). Moreover, it outperforms other DL competitors in both the internal (AUC: 0.840 vs. 0.766 vs. 0.787) and external test cohorts (AUC: 0.826 vs. 0.792 vs. 0.821). The validity of our design is further substantiated through ablation studies on backbone networks, view-specific branches, and individual sequences. In summary, our DL model based on mpMRI and multi-view fusion accurately evaluates the preoperative T-stage of rectal cancer and shows great promise as a valuable tool for clinical assessment.

188 Background: While PD-1/PD-L1 blockade combined with chemoradiotherapy benefits dMMR/MSI-H colorectal cancer (CRC) patients, its efficacy in pMMR/MSS locally advanced rectal cancer (LARC) remains unclear. The mechanisms underlying differential therapeutic responses, particularly immunosuppressive pathways limiting treatment success, require further exploration. Methods: A phase II clinical trial evaluated neoadjuvant chemoradiotherapy (long-course radiotherapy + capecitabine) with Atezolizumab (anti-PD-L1) in 12 MSS LARC patients, followed by total mesorectal excision surgery. Single-cell RNA sequencing was performed on surgical specimens from major pathological responders (MPR) and non-responders (non-MPR), supplemented by spatial transcriptomics, cell-cell communication analysis, and functional validation through in vitro and in vivo testing of TIGIT blockade combined with PD-L1 inhibition and radiotherapy in CRC models. Results: Non-responders exhibited distinct immunosuppressive ecosystems characterized by elevated regulatory T cells, M2-like macrophages, and genomically unstable stem-like epithelial cells. Notably, non-MPR tumors showed significant expansion of functionally exhausted TIGIT+ CD8+ T cells compared to responders, alongside enhanced NECTIN2-TIGIT interactions between cancer-associated fibroblasts and CD8+ T cells. Mechanistically, NECTIN2-TIGIT ligation inhibited the cGAS-STING pathway, suppressing CD8+ T cell cytotoxicity. Therapeutic blockade of TIGIT synergized with PD-L1 inhibition and radiotherapy, effectively reprogramming the tumor immune microenvironment, reducing tumor burden, and extending survival in preclinical models. Conclusions: The NECTIN2-TIGIT axis is a critical immune checkpoint driving resistance to PD-L1 blockade combined with chemoradiotherapy in MSS CRC by inducing CD8+ T cell exhaustion through suppression of the cGAS-STING pathway. Targeting this axis restores anti-tumor immunity, demonstrating that combined TIGIT and PD-L1 blockade with chemoradiotherapy represents a rational therapeutic strategy to overcome resistance in MSS locally advanced rectal cancer.

PURPOSE:Renin-angiotensin system inhibitors (RASIs) have been reported to exert anticancer effects. However, there is still a lack of persuasive evidence for their role in improving postoperative long-term oncologic outcomes of colorectal cancer. This retrospective cohort study emulated a hypothetical randomized controlled trial to evaluate the efficacy of RASIs in improving postoperative long-term oncologic outcomes of patients with stage II/III colon cancer and hypertension. METHODS:Patients were consecutively enrolled from multicenter databases, which contained data from medical centers in Shanghai, China. Eligible criteria were adults with radical resected stage II or III colon adenocarcinoma and hypertension. Eligible patients were classified into the RASI group or the no-RASI group, and propensity score was matched at a 1:1 ratio. The primary outcome was the 3-year disease-free survival (DFS) rate. RESULTS:From 2,640 eligible patients, 2,292 were included in the primary analysis after matching: 1,146 in the RASI group and 1,146 in the no-RASI group. The median follow-up time was 46.3 months. The RASI group had a higher 3-year DFS rate (83.4% v 78.3%; P = .001; hazard ratio [HR], 0.736 [95% CI, 0.617 to 0.878]). The RASI group also had a lower 3-year distant metastasis rate (15.6% v 20.5%; P < .001; HR, 0.717 [95% CI, 0.596 to 0.863]) and a higher 3-year overall survival rate (92.4% v 89.6%; P = .001; HR, 0.682 [95% CI, 0.539 to 0.864]). CONCLUSION:RASIs may improve the postoperative long-term oncologic outcomes for patients with stage II/III colon cancer and hypertension.

To compare the overall survival (OS) and cancer-specific survival (CSS) of right-sided colon cancer patients undergoing CME versus D2 surgery after 5 years of follow-up, and to assess the heterogeneity of treatment effectiveness of CME between different subgroups. The 3-year result of the Radical Extent of lymphadenectomy of Laparoscopic Right Colectomy for colon cancer (RELARC) trial showed that standard D2 dissection should be performed in right-sided colon cancer patients. In patients with lymph node metastasis, complete mesocolic excision (CME) showed potentially favorable results. The parallel, open label, randomized controlled trial was conducted between January, 2016 to December, 2019 in 17 hospitals in China. Of a total of 1072 eligible patients enrolled, 995 patients were included in the modified intention-to-treat analysis. In the present study, the primary outcome was 5-year OS and the secondary outcome was 5-year CSS. The trial is registered with ClinicalTrials.gov (Identifier: NCT02619942). 995 patients were included in the final analysis. There was no significant difference between the 5-year OS (HR: 0.74, 95%CI: 0.51–1.07, P=0.105) or CSS (HR: 0.72, 95%CI: 0.49–1.06, P=0.091) in the CME and D2 groups. CME appears to improve 5-year outcomes in patients with stage III disease (OS: HR: 0.58, 95% CI: 0.37–0.93, P=0.023; CSS: HR: 0.59, 95% CI: 0.37–0.94, P=0.028), particularly in those with pN2 (OS: HR: 0.25, 95% CI: 0.11–0.57, P=0.001; CSS: HR: 0.25, 95% CI: 0.11–0.57, P=0.001), where a statistically significant interaction was identified. Patients with lymphovascular invasion also demonstrated favorable outcomes with CME with significant interaction effect (OS: HR: 0.34, 95% CI: 0.17–0.70; interaction P=0.009; CSS: HR: 0.32, 95% CI: 0.15–0.67, interaction P=0.008). The standard D2 dissection provides oncologic outcomes comparable to CME on the 5-year follow-up. However, CME seems to improve 5-year outcomes in patients with stage III, particularly those with pN2 status, and may confer benefit in patients with LVI.