Immunotherapy has been one of the hot topics in the field of colorectal cancer research in recent years. Patients with microsatellite instability-high (MSI-H) or mismatch repair deficient (dMMR) are the main beneficiaries of immunotherapy. The response rate of patients with dMMR/MSI-H colorectal cancer receiving neoadjuvant immunotherapy is nearly 100%, of which the pathological complete response rate approximately accounts for 60%-67%. The prospect of neoadjuvant immunotherapy in dMMR or MSI-H colorectal cancer patients, especially in the rectal cancer patients, lies in achieving sustainable clinical complete response so as to achieve organ preservation and avoid adverse effects on reproductive, sexual, bowel and bladder function after surgery and radiotherapy. Studies have shown that part of the colorectal cancer patients of microsatellite stability (MSS) or mismatch repair proficient (pMMR) can respond to neoadjuvant immunotherapy in combination with other treatment methods such as radiotherapy and chemotherapy. In pMMR or MSS colorectal cancer, optimizing neoadjuvant immunotherapy regimens and finding effective efficacy prediction biomarkers are important research directions. In neoadjuvant immunotherapy, overcoming primary and secondary resistance and identifying the pseudoprogression and hyperprogression of neoadjuvant immunotherapy are clinical challenges that require attention. This paper comprehensively reviews the research progress, controversies,challenges and future research directions of neoadjuvant immunotherapy (mainly immune checkpoint inhibitors) in colorectal cancer.
Humans ; Neoadjuvant Therapy/methods* ; Colorectal Neoplasms/drug therapy* ; Colonic Neoplasms/pathology* ; Immunotherapy/methods* ; DNA Mismatch Repair ; Microsatellite Instability

Humans ; Hemangiosarcoma/pathology* ; Colonic Neoplasms ; Molecular Biology

Peritoneal metastatic colorectal cancer (pmCRC) is common and has been considered as the terminal stage. The theory of "seed and soil" and "oligometastasis" are the acknowledged hypotheses of pathogenesis of pmCRC. In recent years, the molecular mechanism related to pmCRC has been deeply researched. We realize that the formation of peritoneal metastasis, from detachment of cells from primary tumor to mesothelial adhesion and invasion, depends on the interplay of multiple molecules. Various components of tumor microenvironment also work as regulators in this process. Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) have been widely used in clinical practice as an established treatment for pmCRC. Besides systemic chemotherapy, targeted and immunotherapeutic drugs are also increasingly used to improve prognosis. This article reviews the molecular mechanisms and treatment strategies related to pmCRC.
Humans ; Colorectal Neoplasms/pathology* ; Combined Modality Therapy ; Peritoneal Neoplasms/secondary* ; Hyperthermia, Induced ; Colonic Neoplasms/therapy* ; Rectal Neoplasms/therapy* ; Antineoplastic Combined Chemotherapy Protocols/therapeutic use* ; Prognosis ; Cytoreduction Surgical Procedures ; Survival Rate ; Tumor Microenvironment

Although it has become a consensus in the field of colorectal surgery to perform radical tumor treatment and functional protection under the minimally invasive concept, there exist many controversies during clinical practice, including the concept of embryonic development of abdominal organs and membrane anatomy, the principle of membrane anatomy related to right hemicolectomy, D3 resection, and identification of the inner boundary. In this paper, we analyzed recently reported literature with high-level evidence and clinical data from the author's hospital to recognize and review the membrane anatomy-based laparoscopic assisted right hemicolectomy for right colon cancer, emphasizing the importance of priority of surgical dissection planes, vascular orientation, and full understanding of the fascial space, and proposing that the surgical planes should be dissected in the parietal-prerenal fascial space, and the incision should be 1 cm from the descending and horizontal part of the duodenum. The surgery should be performed according to a standard procedure with strict quality control. To identify the resection range of D3 dissection, it is necessary to establish a clinical, imaging, and pathological evaluation model for multiple factors or to apply indocyanine green and nano-carbon lymphatic tracer intraoperatively to guide precise lymph node dissection. We expect more high-level evidence of evidence-based medicine to prove the inner boundary of laparoscopic assisted radical right colectomy and a more rigorous consensus to be established.
Humans ; Laparoscopy/methods* ; Colonic Neoplasms/pathology* ; Lymph Node Excision/methods* ; Colectomy/methods* ; Dissection

OBJECTIVE: To explore the therapeutic mechanism of Liushen Wan (LSW) against colitis-associated colorectal cancer (CAC) by network pharmacology. METHODS: TCMSP, BATMAN-TCM, CNKI, PubMed, Genecards, OMIM, and TTD databases were used to obtain the related targets of LSW and CAC. The common targets of LSW and CAC were obtained using Venny online website. The PPI network was constructed using Cytoscape 3.8.2 to screen the core targets of LSW in the treatment of CAC. GO and KEGG enrichment analysis were conducted using DAVID database. The therapeutic effect of LSW on CAC was evaluated in a C57BL/6J mouse model of AOM/DSS-induced CAC by observing the changes in body weight, disease activity index, colon length, and size and number of the tumor. HE staining and RT-qPCR were used to analyze the effect of LSW on inflammatory mediators. Immunohistochemistry and TUNEL staining were used to evaluate the effect of LSW on the proliferation and apoptosis of AOM/DSS-treated colon tumor cells. Immunohistochemistry and Western blotting were used to detect the effects of LSW on the expression of TLR4 proteins in CAC mice. RESULTS: Network pharmacology analysis identified 69 common targets of LSW and CAC, and 33 hub targets were screened in the PPI network. KEGG pathway enrichment analysis suggested that the effect of LSW on CAC was mediated by the Toll-like receptor signaling pathway. In the mouse model of AOM/DSS-induced CAC, LSW significantly inhibited colitis-associated tumorigenesis, reduced tumor number and tumor load (P < 0.05), obviously improved histopathological changes in the colon, downregulated the mRNA levels of proinflammatory cytokines, and inhibited the proliferation (P < 0.01) and promoted apoptosis of colon tumor cells (P < 0.001). LSW also significantly decreased TLR4 protein expression in the colon tissue (P < 0.05). CONCLUSION LSW can inhibit CAC in mice possibly by regulating the expression of TLR4 to reduce intestinal inflammation, inhibit colon tumor cell proliferation and promote their apoptosis.
Mice ; Animals ; Toll-Like Receptor 4 ; Colitis-Associated Neoplasms ; Network Pharmacology ; Mice, Inbred C57BL ; Colonic Neoplasms/pathology*

Objective: To explore the efficacy of chemotherapy re-challenge in the third-line setting for patients with metastatic colorectal cancer (mCRC) in the real world. Methods: The clinicopathological data, treatment information, recent treatment efficacy, adverse events and survival data of mCRC patients who had disease progression after treatment with oxaliplatin-based and/or irinotecan-based chemotherapy and received third-line chemotherapy re-challenge from January 2013 to December 2020 at Tianjin Medical University Cancer Institute and Hospital were retrospectively collected. Survival curves were plotted with the Kaplan-Meier method, and the Cox proportional hazard model was used to analyze the prognostic factors. Results: A total of 95 mCRC patients were included. Among them, 32 patients (33.7%) received chemotherapy alone and 63 patients (66.3%) received chemotherapy combined with targeted drugs. Eighty-three patients were treated with dual-drug chemotherapy (87.4%), including oxaliplatin re-challenge in 35 patients and irinotecan re-challenge in 48 patients. The remaining 12 patients were treated with triplet chemotherapy regimens (12.6%). Among them, as 5 patients had sequential application of oxaliplatin and irinotecan in front-line treatments, their third-line therapy re-challenged both oxaliplatin and irinotecan; 7 patients only had oxaliplatin prescription before, and these patients re-challenged oxaliplatin in the third-line treatment. The overall response rate (ORR) and disease control rate (DCR) reached 8.6% (8/93) and 61.3% (57/93), respectively. The median progression free survival (mPFS) and median overall survival (mOS) were 4.9 months and 13.0 months, respectively. The most common adverse events were leukopenia (34.7%) and neutropenia (34.7%), followed by gastrointestinal adverse reactions such as nausea (32.6%) and vomiting (31.6%). Grade 3-4 adverse events were mostly hematological toxicity. Cox multivariate analysis showed that gender (HR=1.609, 95% CI: 1.016-2.548) and the PFS of front-line treatments (HR=0.598, 95% CI: 0.378-0.947) were independent prognostic factors. Conclusion: The results suggested that it is safe and effective for mCRC patients to choose third-line chemotherapy re-challenge, especially for patients with a PFS of more than one year in front-line treatments.
Humans ; Irinotecan/therapeutic use* ; Oxaliplatin/therapeutic use* ; Colorectal Neoplasms/pathology* ; Retrospective Studies ; Fluorouracil ; Colonic Neoplasms/chemically induced* ; Rectal Neoplasms/drug therapy* ; Antineoplastic Combined Chemotherapy Protocols/adverse effects* ; Camptothecin/adverse effects*

Objective: To examine a predictive model that incorporating high risk pathological factors for the prognosis of stage Ⅰ to Ⅲ colon cancer. Methods: This study retrospectively collected clinicopathological information and survival outcomes of stage Ⅰ~Ⅲ colon cancer patients who underwent curative surgery in 7 tertiary hospitals in China from January 1, 2016 to December 31, 2017. A total of 1 650 patients were enrolled, aged (M(IQR)) 62 (18) years (range: 14 to 100). There were 963 males and 687 females. The median follow-up period was 51 months. The Cox proportional hazardous regression model was utilized to select high-risk pathological factors, establish the nomogram and scoring system. The Bootstrap resampling method was utilized for internal validation of the model, the concordance index (C-index) was used to assess discrimination and calibration curves were presented to assess model calibration. The Kaplan-Meier method was used to plot survival curves after risk grouping, and Cox regression was used to compare disease-free survival between subgroups. Results: Age (HR=1.020, 95%CI: 1.008 to 1.033, P=0.001), T stage (T3:HR=1.995,95%CI:1.062 to 3.750,P=0.032;T4:HR=4.196, 95%CI: 2.188 to 8.045, P<0.01), N stage (N1: HR=1.834, 95%CI: 1.307 to 2.574, P<0.01; N2: HR=3.970, 95%CI: 2.724 to 5.787, P<0.01) and number of lymph nodes examined (≥36: HR=0.438, 95%CI: 0.242 to 0.790, P=0.006) were independently associated with disease-free survival. The C-index of the scoring model (model 1) based on age, T stage, N stage, and dichotomous variables of the lymph nodes examined (<12 and ≥12) was 0.723, and the C-index of the scoring model (model 2) based on age, T stage, N stage, and multi-categorical variables of the lymph nodes examined (<12, 12 to <24, 24 to <36, and ≥36) was 0.726. A scoring system was established based on age, T stage, N stage, and multi-categorical variables of lymph nodes examined, the 3-year DFS of the low-risk (≤1), middle-risk (2 to 4) and high-risk (≥5) group were 96.3% (n=711), 89.0% (n=626) and 71.4% (n=313), respectively. Statistically significant difference was observed among groups (P<0.01). Conclusions: The number of lymph nodes examined was an independent prognostic factor for disease-free survival after curative surgery in patients with stage Ⅰ to Ⅲ colon cancer. Incorporating the number of lymph nodes examined as a multi-categorical variable into the T and N staging system could improve prognostic predictive validity.
Male ; Female ; Humans ; Prognosis ; Neoplasm Staging ; Retrospective Studies ; Nomograms ; Lymph Nodes/pathology* ; Risk Factors ; Colonic Neoplasms/surgery*

Objective: To explore the efficacy of chemotherapy re-challenge in the third-line setting for patients with metastatic colorectal cancer (mCRC) in the real world. Methods: The clinicopathological data, treatment information, recent treatment efficacy, adverse events and survival data of mCRC patients who had disease progression after treatment with oxaliplatin-based and/or irinotecan-based chemotherapy and received third-line chemotherapy re-challenge from January 2013 to December 2020 at Tianjin Medical University Cancer Institute and Hospital were retrospectively collected. Survival curves were plotted with the Kaplan-Meier method, and the Cox proportional hazard model was used to analyze the prognostic factors. Results: A total of 95 mCRC patients were included. Among them, 32 patients (33.7%) received chemotherapy alone and 63 patients (66.3%) received chemotherapy combined with targeted drugs. Eighty-three patients were treated with dual-drug chemotherapy (87.4%), including oxaliplatin re-challenge in 35 patients and irinotecan re-challenge in 48 patients. The remaining 12 patients were treated with triplet chemotherapy regimens (12.6%). Among them, as 5 patients had sequential application of oxaliplatin and irinotecan in front-line treatments, their third-line therapy re-challenged both oxaliplatin and irinotecan; 7 patients only had oxaliplatin prescription before, and these patients re-challenged oxaliplatin in the third-line treatment. The overall response rate (ORR) and disease control rate (DCR) reached 8.6% (8/93) and 61.3% (57/93), respectively. The median progression free survival (mPFS) and median overall survival (mOS) were 4.9 months and 13.0 months, respectively. The most common adverse events were leukopenia (34.7%) and neutropenia (34.7%), followed by gastrointestinal adverse reactions such as nausea (32.6%) and vomiting (31.6%). Grade 3-4 adverse events were mostly hematological toxicity. Cox multivariate analysis showed that gender (HR=1.609, 95% CI: 1.016-2.548) and the PFS of front-line treatments (HR=0.598, 95% CI: 0.378-0.947) were independent prognostic factors. Conclusion: The results suggested that it is safe and effective for mCRC patients to choose third-line chemotherapy re-challenge, especially for patients with a PFS of more than one year in front-line treatments.
Humans ; Irinotecan/therapeutic use* ; Oxaliplatin/therapeutic use* ; Colorectal Neoplasms/pathology* ; Retrospective Studies ; Fluorouracil ; Colonic Neoplasms/chemically induced* ; Rectal Neoplasms/drug therapy* ; Antineoplastic Combined Chemotherapy Protocols/adverse effects* ; Camptothecin/adverse effects*

Colorectal cancer is the third most common cancer in the world. The treatments include surgery, chemotherapy, radiotherapy and targeted therapy. The guidelines of many tumor types have been rewritten with the advent of immune checkpoint inhibitors. There are significant differences in the efficacy of immune checkpoint inhibitors in colorectal cancer according to microsatellite status. Microsatellite instability-high (MSI-H) colorectal cancer has made a breakthrough in immunotherapy, whether in the late-line, first-line, adjuvant or neoadjuvant therapy. The success of KEYNOTE-177 study has changed the guidelines with pembrolizumab becoming a standard treatment in the first-line treatment of MSI-H advanced colorectal cancer. The NICHE study, which used immunotherapy as neoadjuvant treatment of colorectal cancer, has made exciting achievements in MSI-H colorectal cancer. For microsatellite stability (MSS) colorectal cancer, many studies are ongoing, and immunotherapy is still unable to challenge the status of traditional treatment. In this paper, we review the clinical trials related to immune checkpoint inhibitors of colorectal cancer, expecting to provide references for the development of colorectal cancer immunotherapy.
Clinical Trials as Topic ; Colonic Neoplasms/drug therapy* ; Colorectal Neoplasms/pathology* ; Humans ; Immune Checkpoint Inhibitors/therapeutic use* ; Immunotherapy

Splenic flexure colon cancer occurs at a relatively lower rate than colon cancer of other sites. It is also associated with more advanced disease and higher rate of acute obstruction. The splenic flexure receives blood supply from both superior and inferior mesenteric arteries (SMA and IMA), and therefore has lymphatic drainage to both areas. The blood supply is also highly variable, causing difficulties in determining the main feeding vessels and the main direction of lymph drainage. Few studies with limited cases focused on this specific tumor site with respect to the patterns of lymph node spread, especially the main lymph node status and the value of its dissection. The lack of information limits the development of a consensus on the extent of surgical resection and lymphadenectomy. Adequate mobilization of the colon facilitates a sufficient length of bowel resection and the high ligation of feeding arteries from both SMA and IMA. Further evidence on the chnoice of procedures and the extent of lymph node dissection need multicenter collaboration, with the use of modern techniques, including CT 3D reconstruction of the colon and angiography, as well as intraoperative fluorescent real-time imaging of lymph nodes.
Colon, Transverse/surgery* ; Colonic Neoplasms/surgery* ; Humans ; Laparoscopy ; Lymph Node Excision/methods* ; Lymph Nodes/pathology* ; Mesenteric Artery, Inferior/surgery*