Background: Conventional laparoscopic-assisted surgery (CLS) for sigmoid and upper rectal cancer requires an abdominal extraction incision, linked to pain, surgical site infection and poor cosmesis. Natural orifice specimen extraction surgery (NOSES) removes tumours via the anus without abdominal wounds, yet high-quality randomised controlled trial evidence on long-term oncological safety remains scarce. This multicentre trial aimed to verify whether NOSES is non-inferior to CLS regarding 3-year disease-free survival (DFS), alongside evaluating short-term recovery and complications. Methods: This open-label, parallel-group, non-inferiority randomised trial enrolled patients with cT1-3N0-2M0 sigmoid/upper rectal adenocarcinoma across 13 Chinese tertiary centres between Aug 30, 2020, and Nov 5, 2023. Participants were 1:1 allocated via centre-stratified web randomisation; outcome assessors at discharge were masked to group assignment. The prespecified non-inferiority margin for 3-year DFS was 10%. Primary analysis used the modified intention-to-treat (mITT) population; per-protocol (PP) data served for sensitivity analysis. Trial registration: ChiCTR2000036314. Findings: 516 patients were randomised (258 per group). The mITT survival cohort included 205 CLS and 208 NOSES participants, with median follow-up of 36.9 months. 3-year DFS was 89.7% (95% CI 85.1-94.6) for CLS and 94.7% (91.1-98.4) for NOSES (absolute difference 5.0%, 95% CI -3.4 to 13.3, meeting non-inferiority; log-rank p=0.088). 3-year overall survival and local recurrence rates were similar between groups. NOSES patients had earlier first flatus (p<0.001), lower postoperative NRS pain scores, and less rescue analgesic use (17.5% vs 37.4%, p<0.001). Overall 30-day complication rate was numerically lower in NOSES (12.0% vs 18.3%, p=0.056); all incisional surgical site infections occurred only in the CLS group (6.0%). Hospital costs were higher with NOSES (mean difference 6525 CNY, p<0.001). No 30-day deaths occurred in either arm. Interpretation: For selected patients with cT1-3N0-2M0 sigmoid or upper rectal cancer, NOSES performed by experienced surgeons delivers non-inferior long-term oncological outcomes versus CLS, with meaningful improvements in postoperative pain, bowel recovery and surgical site infection risk. NOSES represents a patient-friendly minimally invasive option for suitable candidates.

Aim:In proficient mismatch repair (pMMR) non metastatic rectal cancer, standard neoadjuvant chemoradiotherapy (nCRT) yields low pathological and clinical complete response rates. Early randomized trials suggest adding PD 1 inhibitors may increase response but randomized evidence has not been synthesized. Methods:We performed a systematic review and meta-analysis of phase II-III randomized trials comparing nCRT plus PD 1 inhibitor versus nCRT alone in adults with untreated pMMR non metastatic rectal cancer. PubMed, Web of Science, Embase and CENTRAL were searched to 30 Sept 2025. Two reviewers extracted data. Dichotomous outcomes were pooled as risk ratios (RRs) with 95% confidence intervals (CIs) using a DerSimonian-Laird random effects model; heterogeneity was assessed by I2. Prespecified subgroup analyses compared short course versus long course radiotherapy. Results:Six trials (n=935; nCRT+PD 1 = 461; nCRT=474) were included; agents evaluated included pembrolizumab, sintilimab, tislelizumab and camrelizumab. PD 1 addition significantly increased pathological complete response (pCR) (RR 1.79, 95% CI 1.34-2.40) and showed a non-definitive increase in clinical complete response (cCR) (RR 1.67, 95% CI 0.89-3.13). No clear differences were seen for R0 resection, sphincter preservation, grade ≥3 neoadjuvant toxicity, or surgery related adverse events. Subgroup analysis suggested greater pCR benefit with short course radiotherapy. Conclusion:Among patients with pMMR non-metastatic rectal cancer, adding PD-1 inhibitors to standard nCRT improves pCR-most markedly when combined with short-course radiotherapy-with no statistically significant increase detected in high-grade neoadjuvant toxicity or major surgical morbidity. These randomized data support progression to confirmatory phase III trials to define optimal sequencing, regimen standardization and long-term oncologic and functional outcomes.Systematic Review Registration: https://www.crd.york.ac.uk/prospero/, identifier 420251137668.

The Tianhe Procedure is a functional sphincter-preserving surgical approach developed for patients with rectal cancer following radiotherapy. This technique involves proximal extended resection of the colon beyond the pelvic cavity, followed by anastomosis of the non-irradiated proximal colon to the distal rectum or anal canal. This strategy aims to reduce the incidence of anastomotic complications and postoperative bowel dysfunction. However, there is currently a lack of standardized practice guidelines for implementing the Tianhe Procedure in China. Therefore, the Chinese Radiation Intestinal Injury Research Group, the Colorectal Surgery Group of Surgery Branch of the Chinese Medical Association, the Anorectal Branch of Chinese Medical Doctor Association, the Colorectal Cancer Committee of the Chinese Medical Doctor Association, the Colorectal Cancer Committee of China Anti-cancer Association, and the Gastrointestinal Surgical Branch of Guangdong Medical Doctor Association have jointly convened a panel of national experts to discuss and establish this standardized surgical procedure. This standard, based on the latest evidence from literature, research advancements, and expert experience, focuses on key aspects of the Tianhe Procedure, including its precise definition, indications, critical procedural steps, postoperative complications, and functional rehabilitation strategies. It aims to promote standardized implementation and broader clinical adoption of this innovative surgical technique.

Purpose:To evaluate the incidence and risk factors of severe postoperative complications in patients aged ≥80 years undergoing laparoscopic colorectal cancer surgery. Patients and Methods:Patients aged ≥80 years who underwent laparoscopic colorectal cancer surgery between February 2007 and September 2018. Severe complications were defined as Clavien-Dindo grade III or higher. Univariate and multivariate logistic regression analyses were performed to identify risk factors. Results:Among 170 patients, 26 (15.3%) experienced severe postoperative complications. Gastrointestinal events were most common (8.0%), followed by respiratory (3.5%) and cardiovascular (2.9%) complications. Two patients (1.2%) died postoperatively. Multivariate analysis identified estimated blood loss >100 mL (OR = 4.53, 95% CI: 1.75-11.70, P < 0.01) and age ≥85 years (OR = 4.48, 95% CI: 1.27-15.79, P = 0.02) as independent risk factors. Hemoglobin <120 g/L (OR = 2.56, 95% CI: 0.99-6.60, P = 0.05) and ASA III (OR = 2.49, 95% CI: 0.98-6.35, P = 0.06) showed borderline significance. Conclusion:Severe complications occurred in 15.3% of octogenarians undergoing laparoscopic colorectal cancer surgery. Age ≥85 years and intraoperative blood loss >100 mL were independent risk factors. Preoperative anemia and ASA III were borderline predictors. These factors may aid in perioperative risk stratification and surgical decision-making in elderly patients.

Serum bile acids (BAs) emerge as risk factors for cancer, but their roles in colorectal cancer (CRC) remain unclear. We show that glycocholic acid (GCA), a primary BA, is elevated in the serum of CRC patients. In a mouse CRC model, GCA promotes tumor programmed death-ligand 1 (PD-L1) expression in tumors, suppressing CD8⁺ T cell-mediated antitumor immunity and facilitating tumor growth. Mechanistically, GCA inhibits the BA receptor farnesoid X receptor (FXR), a transcriptional repressor for SRY-box transcription factor 14 (SOX14). Loss of FXR repression upregulates SOX14-mediated expression of zinc finger DHHC-type palmitoyl transferase 9 (DHHC9), thereby reducing PD-L1 palmitoylation and stabilization. Silencing SOX14 or DHHC9, or activating FXR, synergizes with anti-PD-1 therapy, reducing tumor growth in GCA-treated mice. These findings uncover a mechanism that GCA remodels the tumor microenvironment to mediate CRC resistance to immunotherapy, highlighting therapeutic opportunities targeting the FXR-PD-L1 axis in CRC patients with elevated serum GCA.

Background:Repetitive elements account for a large proportion of the human genome and undergo alterations during early tumorigenesis. However, the exclusive fragmentation pattern of DNA-derived cell-free repetitive elements (cfREs) remains unclear. Methods:This study enrolled 32 healthy volunteers and 112 patients with five types of cancer. A novel repetitive fragmentomics approach was proposed to profile cfREs using low-pass whole genome sequencing (WGS). Five innovative repetitive fragmentomic features were designed: fragment ratio, fragment length, fragment distribution, fragment complexity, and fragment expansion. A machine learning-based multimodal model was developed using these features. Results:The multimodal model achieved high prediction performance for early tumor detection, even at ultra-low sequencing depths (0.1×, AUC = 0.9824). Alu and short tandem repeat (STR) were identified as the primary cfREs after filtering out low-efficiency subfamilies. Characterization of cfREs within tumor-specific regulatory regions enabled accurate tissue-of-origin (TOO) prediction (0.1×, accuracy = 0.8286) and identified aberrantly transcribed tumor driver genes. Conclusion:This study highlights the abundance of repetitive DNA in plasma. The innovative fragmentomics approach provides a sensitive, robust, and cost-effective method for early tumor detection and localization.

BACKGROUND Endoscopy allows for the direct observation of primary tumor characteristics and responses after neoadjuvant treatment. However, reports on endoscopic evaluation following neoadjuvant immunotherapy remain limited. AIM To examine the predictive value of endoscopic findings of primary tumors for responses to neoadjuvant immunotherapy. METHODS This retrospective study, conducted at a tertiary center in China, evaluated 74 patients with colorectal cancer, including 17 with deficient mismatch repair (dMMR) and 15 with proficient mismatch repair (pMMR) tumors. Patients underwent neoadjuvant immunotherapy followed by surgery. Endoscopic findings before and after neoadjuvant immunotherapy were reviewed and compared with the pathology of the resected specimens. RESULTS In the pMMR group (n = 57 evaluable patients), endoscopy identified 11/17 patients who achieved a complete response (CR), while misidentifying 1/40 patients with residual disease as CR (64.7% vs 2.5%, P < 0.01). Conversely, 22/40 patients with residual disease were accurately identified as achieving a partial response (PR), with 1/17 patients who achieved CR misclassified as PR (55.0% vs 5.9%, P < 0.01). The sensitivity, specificity, and accuracy of endoscopic diagnosis for pathological CR were 64.7%, 97.5%, and 87.7%, respectively. In the dMMR cohort, endoscopy classified 9/17 patients as CR and 2 of the remaining patients with residual tumors as PR (64.3% vs 66.7%, P = 0.73). The method demonstrated 100% sensitivity and 82.4% accuracy in diagnosing pathological CR. CONCLUSION Endoscopic evidence of CR or PR was well correlated with postoperative pathological outcomes in the pMMR cohort. Despite endoscopic indications of tumor residue, a complete pathological response post-surgery was possible in the dMMR cohort.

To explore the application effect of the technique of “priority dissecting of the inferior mesenteric artery combined with complete medial approach (IMA-CMA)” in laparoscopic left-sided colon cancer radical resection. A total of 99 patients who underwent laparoscopic left-sided colon cancer radical resection with splenic flexure mobilization between September 2021 to May 2023 were included. Sixty-eight of these patients were analyzed after propensity score matching (PSM). The perioperative characteristics were compared. Among these enrolled patients, 45 underwent the traditional approach, and 54 underwent IMA-CMA approach. After PSM, the patients were matched to include 34 patients in each group, with no significant differences in the sex (p = 0.618) or location of tumor (p = 0.798) between the two groups. The patients in IMA-CMA group had shorter operating time (p = 0.032), less intraoperative blood loss (p = 0.003), a higher number of harvested lymph nodes (p = 0.044) and center group lymph nodes(p = 0.037), and a shorter postoperative hospital stay (p = 0.011). Number of positive lymph nodes and postoperative complications were not significantly different between the two groups. The technique of IMA-CMA for splenic flexure mobilization is safe and feasible. It can reduce operating time, intraoperative blood loss and postoperative hospital stay, which is conducive to achieving a thorough D3 lymphadenectomy without increasing the incidence of perioperative complications.

BackgroundNeoadjuvant combination immunotherapy is a potential treatment option for patients with proficient mismatch repair/microsatellite stable colorectal cancer. Preoperative screening via endoscopy and imaging examinations could help identify patients who may potentially achieve a complete response after neoadjuvant combination immunotherapy. This study aims to evaluate the diagnostic accuracy of endoscopic and imaging examinations in predicting pathological complete response after neoadjuvant combination immunotherapy.MethodsThis single-center, retrospective, observational study included patients diagnosed with colorectal cancer by biopsy between 2015 and 2023 at a tertiary referral center. The main outcome measures included endoscopic examination, imaging findings, and pathological results after neoadjuvant combination immunotherapy.ResultsThis study included 36 patients with locally advanced proficient mismatch repair colorectal cancer. Postoperative pathology revealed that 17 patients (47.2%) achieved a complete response (ypT0N0). The sensitivity, specificity, and accuracy of the endoscopic ypT0N0 diagnosis were 62.5%, 80.0%, and 80.6%, respectively; those of imaging-based ypT0N0 diagnosis were 43.8%, 100%, and 75.0%, respectively; and those of the combined diagnosis were 37.5%, 100%, and 72.2%, respectively. The areas under the receiver-operating characteristic curve for the endoscopic and imaging ypT0N0 diagnoses were 0.768 and 0.706, respectively.ConclusionsThe specificities of endoscopy and imaging for diagnosing complete response after neoadjuvant combination immunotherapy for colorectal cancer were high; however, sensitivities were low. Therefore, radical surgery should still be recommended for patients with an incomplete response based on either examination. Larger scale studies are required to determine if a watch-and-wait strategy is suitable for patients with a complete response based on these two examinations.

BACKGROUND:The aim of the study was to increase the specificity and targeting of tumour imaging, targeting molecules that enable the simultaneous recognition and binding of multiple tumour-associated receptors. We constructed a NIR-II fluorescence probe based on a bispecific antibody to epidermal growth factor receptor (EGFR) and cellular mesenchymal-epithelial transition factor (c-Met) for visualising colorectal cancers (CRCs) and metastatic lymph nodes. METHODS:The expression of EGFR and c-Met in tumour and metastatic lymph node specimens from patients with CRC was examined using immunohistochemistry. The EGFR and c-Met bispecific antibody (Rybrevant) was labelled, and its cell-specific binding ability was assessed using laser confocal microscopy. Subcutaneous CRC and orthotopic tumour models were constructed to evaluate the fluorescence imaging of the probe in vivo. To assess the performance of Rybrevant-IRDye800CW in the differential diagnosis of metastatic lymph nodes, a CRC lymph node metastasis model was constructed using human CRC cells implanted in mouse claw pads. Finally, surgically resected CRC tumours and lymph node specimens were incubated with Rybrevant-IRDye800CW for fluorescence NIR-II imaging to evaluate the efficacy of Rybrevant-IRDye800CW for preclinical visualisation. FINDINGS:The combined expression rate of EGFR and c-Met in CRC and metastatic lymph nodes was significantly higher than the single-target expression rate. The bispecific probe Rybrevant-IRDye800CW was successfully synthesised, and its fluorescence signal could be extended up to 1600 nm using NIR-II imaging. Cell incubation experiments showed that the fluorescence intensity of Rybrevant-IRDye800CW was strongly correlated with EGFR and c-Met overexpression of the cells. NIR-II in vivo fluorescence imaging showed that double-positively expressing subcutaneous tumours significantly uptook Rybrevant-IRDye800CW after tail vein injection of the probe, which rapidly accumulated within the tumours in about 6 h. In EGFR and or c-Met blockade assays, subcutaneous tumours showed weaker uptake of Rybrevant-IRDye800CW. Similarly, Rybrevant-IRDye800CW was specifically identified in orthotopic CRC and lymph node metastasis models, with all orthotopic tumours showing high tumour-to-background ratios in NIR-II imaging. In a NIR-II preclinical study, Rybrevant-IRDye800CW could specifically identify fresh human CRC and its metastatic lymph node tissue. INTERPRETATION:This study confirmed the complementary EGFR and c-Met expression in CRC and its metastatic lymph nodes. Compared to single-target probes, EGFR and c-Met dual-specific fluorescent probes identified CRC and its metastatic lymph nodes using NIR-II imaging. Thus, NIR-II-guided R0 surgery was performed to resect the CRC and metastatic lymph nodes. FUNDINGS:This study was supported by the Beijing Natural Science Foundation (Grant numbers: L222054, 7244517, 4232058, L248026, L232020), National Natural Science Foundation of China (NSFC) (92059207, 92359301, 92259303, 62027901, 81930053, 81227901, U21A20386), CAS Youth Interdisciplinary Team (JCTD-2021-08), and the Fundamental Research Funds for the Central Universities (Grant no. JK2024-2-35-02).

BACKGROUND:The therapeutic efficacy and mode of combining immunotherapy with neoadjuvant chemoradiotherapy in proficient mismatch repair (pMMR)/microsatellite stable (MSS) locally advanced rectal cancer (LARC) remain uncertain. METHODS:In this multicenter, randomized, seamless phase 2/3 trial (ClinicalTrials.gov: NCT05484024), eligible participants were randomly assigned (1:1) to receive short-course radiotherapy (SCRT) (5 Gy × 5), followed by 4 cycles of capecitabine and oxaliplatin or 6 cycles of leucovorin, oxaliplatin, and fluorouracil, with (iTNT group) or without (total neoadjuvant therapy [TNT] group) 4 cycles of sintilimab. Following neoadjuvant therapy, participants underwent surgery or a watch-and-wait strategy based on clinical complete response. The primary endpoints were the complete response (CR) rate for phase 2 and the 3-year disease-free survival (DFS) rate for phase 3. FINDINGS:218 patients were randomized to the iTNT group (n = 110) and the TNT group (n = 108). All patients completed SCRT, with 88.2% in the iTNT group and 93.5% in the TNT group completing 4 cycles of neoadjuvant treatment. The CR rate was significantly higher in the iTNT group (45.5% vs. 25.0%; p = 0.003). Grade 3-4 treatment-related adverse events were reported in 34.5% of the iTNT group and 19.4% of the TNT group (p = 0.012), with thrombocytopenia, diarrhea, leukopenia, and neutropenia being the most frequently observed. Grade 3-4 immune-related adverse events occurred in 5.5% of patients in the iTNT group. CONCLUSIONS:The addition of the PD-1 inhibitor sintilimab significantly enhances the CR rate compared to SCRT-based TNT, with favorable tolerability in patients with pMMR/MSS LARC. FUNDING:This work was funded by the National Natural Science Foundation of China (82473248) and the Shenzhen Medical Research Fund (C2301001).

The diagnosis of lymph node metastasis (LNM) is essential for colorectal cancer (CRC) treatment. The primary method of identifying LNM is to perform frozen sections and pathologic analysis, but this method is labor-intensive and time-consuming. Therefore, combining intraoperative fluorescence imaging with deep learning (DL) methods can improve efficiency. The majority of recent studies only analyze uni-modal fluorescence imaging, which provides less semantic information. In this work, we mainly established a multi-modal fluorescence imaging feature fusion prediction (MFI-FFP) model combining white light, fluorescence, and pseudo-color imaging of lymph nodes for LNM prediction. Firstly, based on the properties of various modal imaging, distinct feature extraction networks are chosen for feature extraction, which could significantly enhance the complementarity of various modal information. Secondly, the multi-modal feature fusion (MFF) module, which combines global and local information, is designed to fuse the extracted features. Furthermore, a novel loss function is formulated to tackle the issue of imbalanced samples, challenges in differentiating samples, and enhancing sample variety. Lastly, the experiments show that the model has a higher area under the receiver operating characteristic (ROC) curve (AUC), accuracy (ACC), and F1 score than the uni-modal and bi-modal models and has a better performance compared to other efficient image classification networks. Our study demonstrates that the MFI-FFP model has the potential to help doctors predict LNM and shows its promise in medical image analysis.

A T cell-inflamed tumor microenvironment is predictive of better prognosis and clinical response to immunotherapy. Proteinase-activated receptor 2 (PAR2), a member of G-protein coupled receptors is involved in inflammatory process and the progression of various cancers. However, the role of PAR2 in modulating the tumor microenvironment remains unclear. Here, we found that PAR2 high-expression was associated with a favorable prognosis in patients with colorectal cancer. Intriguingly, PAR2 expression in human colorectal cancer was mainly confined to tumor cells and was significantly associated with CD8+ T cell infiltration. Tumor-intrinsic PAR2 deficiency blunted antitumor immune responses to promote tumor growth and attenuated the therapeutic efficacy of anti-PD1 in a mouse model of colon cancer. Tumors with downregulated PAR2 showed decreased CD8+ T cell infiltration and impaired effector function. Mechanistically, PAR2 activation in tumor cells induced CXCL9 and CXCL10 production via PI3K/AKT/mTOR signaling, thereby enhancing CD8+ T cell recruitment in the tumor microenvironment. In addition, PAR2 was essential for dendritic cell activation and differentiation towards conventional type 1 subset. PAR2 deficiency in dendritic cells markedly impaired their ability to prime CD8+ T cells and control tumor growth in vivo. Thus, our findings identify new roles for PAR2 in promoting antitumor immunity and provide a promising target to improve immunotherapy efficacy in colorectal cancer.

Anastomotic leakage (AL) is a serious complication in colorectal surgery, particularly after laparoscopic intersphincteric resection (LsISR) for ultra-low rectal cancer. This study evaluates the effectiveness of ICG fluorescence laparoscopic (FL) resection in reducing AL and improving recovery, especially in high-BMI patients. A retrospective cohort study was conducted on patients undergoing LsISR for ultra-low rectal adenocarcinoma from January 2012 to July 2023, comparing FL (n = 133) and non-FL groups (n = 266). The primary endpoint was the incidence of anastomotic leakage, including symptomatic AL. Secondary endpoints included intraoperative blood loss, lymph node yield, and short-term recovery parameters such as bowel function recovery, soft diet initiation, and hospital stay.Propensity score matching (PSM) was used to reduce baseline differences. In the PSM cohort, the FL group had a significantly lower AL rate (3.0

There have been previously reported associations between the gut microbiota, immune cells, and colorectal cancer; however, the specific mechanisms underlying these relationships remain largely unexplored and require further research. Therefore, in this study, we aimed to unravel the interactions between the gut microbiota, immune cells, and colorectal cancer. The analysis used genome-wide association study (GWAS) data encompassing 207 microbial taxa and 205 functional pathways and data on 731 immune cell phenotypes. Colorectal cancer data on 6 581 cases and 463 421 controls were sourced from the Integrative Epidemiology Unit Open GWAS Project. Univariate inverse-variance weighted Mendelian randomization analysis was used to identify gut microbial taxa associated with colorectal cancer. Mediation analysis was used to identify the mediating role of specific immune cells in the link between gut bacteria and colorectal cancer. Univariate inverse-variance weighted Mendelian randomization analysis revealed that several microbial taxa from the Actinobacteria and Firmicutes phyla were significantly associated with colorectal cancer. Coriobacteriaceae (odds ratio [OR]: 0.84, 95

BACKGROUND:Diverting stoma (DS) is routinely proposed in intersphincteric resection for ultralow rectal cancer, but it is associated with increased stoma-related complications and economic burden. Appropriate patient selection and operative strategies to avoid stoma formation need further elucidation. AIM:To select patients who may not require DS. METHODS:This study enrolled 505 consecutive patients, including 84 who underwent stoma-free (SF) intersphincteric resection. After matching, patients were divided into SF (n = 78) and DS (n = 78) groups. The primary endpoint was the anastomotic leakage (AL) rate within 6 months and its protective factors for both the total and SF cohorts. The secondary endpoints included overall survival and disease-free survival. RESULTS:The AL rate was greater in the SF group than in the DS group (12.8% vs 2.6%, P = 0.035). Male sex [(odds ratio (OR) = 2.644, P = 0.021], neoadjuvant chemoradiotherapy (nCRT) (OR = 6.024, P < 0.001), and tumor height from the anal verge ≤ 4 cm (OR = 4.160, P = 0.007) were identified as independent risk factors. Preservation of the left colic artery (LCA) was protective in both the total cohort (OR = 0.417, P = 0.013) and the SF cohort (OR = 0.312, P = 0.027). The female patients who did not undergo nCRT and had preservation of the LCA experienced a significantly lower incidence of AL (2/97, 2.1%). The 3-year overall survival or disease-free survival did not significantly differ between the groups. CONCLUSION:Female patients who do not receive nCRT may avoid the need for DS by preserving the LCA without increasing the risk of AL or compromising oncological outcomes.

To identify the clinical and molecular factors that effectively predict pathological complete response (pCR) and assess the safety of patients receiving neoadjuvant combination immunotherapy. This retrospective study evaluated 81 patients with colorectal cancer (CRC) at a Chinese tertiary center between 2015 and 2023. The cohort included 24 patients with deficient mismatch repair (dMMR) and 57 patients with proficient mismatch repair (pMMR) tumors. Patients were treated with a neoadjuvant combination of immunotherapy and surgery. We divided 81 patients into pCR (40.7

In colon cancer patients with tumor-associated inflammatory adhesions (TAIA), the preoperative clinical staging is cT4b, but postoperative pathology reveals that the tumor has not invaded surrounding organs (non-pT4b). We aimed to investigate the impact of TAIA on prognosis and treatment strategies for colon cancer patients. Colon cancer patients from the Surveillance, Epidemiology, and End Results (SEER) database (2010 to 2019) and Chinese multicenter cohort were included to compare survival differences between the TAIA and non-TAIA groups. A Cox proportional hazards model was used to evaluate independent risk factors for survival in colon cancer patients. Additionally, we analyzed the impact of adjuvant chemotherapy on survival in TAIA patients. A total of 112,659 colon cancer patients from the SEER database and 881 colon cancer patients from the Chinese database were included in this study. After PSM, both cohorts found that patients in the TAIA group exhibited worse overall survival (P < 0.05) and cancer-specific survival (P < 0.05). Additionally, the Cox multivariate proportional hazards model identified TAIA as an independent risk factor for cancer-specific survival in colon cancer patients (SEER: HR 1.45, 95

To comprehensively evaluate the efficacy and safety of neoadjuvant therapy combined with immunotherapy in patients with MMR-proficient/microsatellite stable (pMMR/MSS) non-metastatic rectal cancer. Major databases, including PubMed, Web of Science, Cochrane Library, Embase, ASCO, and ESMO, were systematically searched for studies on neoadjuvant therapy combined with immunotherapy in pMMR/MSS non-metastatic rectal cancer, up to April 2025. Statistical analysis utilized Stata 18 software, calculating outcomes with pathological complete response (pCR), major pathological response (MPR), clinical complete response (cCR), R0 resection, anal preservation rate, and the incidence of adverse events. Heterogeneity and publication bias were evaluated using I² and funnel plots. A total of 21 trial cohorts from 18 studies were included in the meta-analysis. The overall pooled pCR, MPR, and cCR rates were 35