Risk factors for metachronous peritoneal carcinomatosis after radical resection for patients with nonmetastatic pT3-4 colon cancer.

BACKGROUND: Patients with nonmetastatic pT3-4 colon cancers are prone to develop metachronous peritoneal carcinomatosis (mPC). Risk factors for mPC and the influence of mutant kirsten rat sarcoma viral oncogene (KRAS)/neuroblastoma rat sarcoma (NRAS)/v-raf murine sarcoma viral oncogene homolog B1 (BRAF) and DNA mismatch repair (MMR) status on mPC remain to be described in these patients. METHOD: All enrolled patients were identified from the prospectively collected colorectal cancer database of a tertiary referral hospital between 2013 and 2018. Multivariate analysis was used to identify risk factors associated with mPC. RESULTS: Of the 1689 patients with nonmetastatic pT3-4 colon carcinoma, 8.4% (142/1689) progressed to mPC. Endoscopic obstruction (HR = 3.044, p < 0.001), elevated CA125 (HR = 1.795, p = 0.009), pT (T4a vs. T3, HR = 2.745, p < 0.001; T4b vs. T3, HR = 3.167, p = 0.001), pN (N1 vs. N0, HR = 2.592, p < 0.001; N2 vs. N0, HR = 4.049, p < 0.001), less than 12 lymph nodes harvested (HR = 2.588, p < 0.001), mucinous or signet ring cell carcinoma (HR = 1.648, p = 0.038), perineural invasion (HR = 1.984, p < 0.001), and adjuvant chemotherapy (HR = 1.522, p = 0.039) were strongly related to mPC but that mutant KRAS/NRAS/BRAF and MMR status was not associated with mPC. CONCLUSION: This study identified the high-risk factors for mPC in patients with nonmetastatic pT3-4 colon carcinoma, and these factors should be considered in selective preventive therapy and close follow-up for patients subsequently deemed to have high risk for mPC.

Enteral nutrition is associated with a decreased risk of surgical intervention in Crohn's disease patients with spontaneous intra-abdominal abscess.

BACKGROUND: The impact of enteral nutrition (EN) on surgical risk in Crohn's disease (CD) patients suffering from spontaneous intra-abdominal abscess (IAA) was evaluated. METHODS: CD patients diagnosed with spontaneous IAA from 2008 to 2015 were included in the study. The impact of EN on surgical risk was evaluated using both univariate and multivariate analyses. RESULTS: A total of 87 patients were enrolled, 66 (75.9%) were male. The mean age at the development of an abscess was 30.2 ± 10.1 years and the median duration of illness from CD diagnosis until the development of an abscess was three (2-6) years. After a median follow-up of 1.9 (1.1-2.9) years, surgical intervention was performed in 42 patients (48.3%). Patients treated with EN were less likely to require surgical intervention (26.1% vs 56.3%, p = 0.01). Multivariate analysis showed that EN was an independent protective factor for the risk of surgery with a hazard ratio of 0.27 (95% confidence interval: 0.11-0.65, p = 0.004) after adjusting for abdominal pain, history of abdominal surgery, concomitant intestinal stenosis and prior use of antibiotics within three months. CONCLUSIONS: Surgical intervention is common for CD patients with IAA. Appropriate application of EN may help obviate the need for surgical treatment.

Prognostic Implications of Endoscopic Obstruction in Patients with Pathological Stage II Colon Cancers: a Single-Center Retrospective Cohort Study.

BACKGROUND: The prognostic effect of endoscopic obstruction (eOB) on the survival of stage II colon cancer patients and the role of eOB in guiding postoperative adjuvant chemotherapy of stage II colon cancer are little known. METHODS: In this retrospective, single-center cohort study, patients who had undergone curative surgery and preoperative colonoscope for stage II colon carcinoma were included. The eOB was defined as severe luminal colon obstruction that prevented the standard colonoscope from passing beyond the tumor. The association between eOB and stage II colon cancer survival and the predictive role of eOB for adjuvant chemotherapy were evaluated using multivariate Cox regression analysis. RESULTS: Of 1102 included patients, 616 (55.9%) had eOB and 486 (44.1%) had no eOB. The median follow-up was 49 months (interquartile range, 38-68 months). Kaplan-Meier curves showed that patients with eOB had poor 5-year overall survival (OS; 85.3% vs. 95.3%, p < 0.001) compared to patients without eOB. Five-year disease-free survival (DFS; 78.5% vs. 87.6%, p = 0.004) was also poor in these patients. Multivariate analysis demonstrated eOB was a significant prognostic factor for poor OS (hazard ratio [HR] = 2.531, p < 0.001), but not for DFS (p = 0.081). Even when patients with clinical colonic obstruction were excluded from the population with eOB, the worse OS (HR = 2.262, p = 0.001) was observed. The OS and DFS of eOB patients improved slightly after adjuvant chemotherapy, but there was no statistical significance. CONCLUSIONS: Stage II colon cancer patients with eOB have a poor prognosis. However, whether eOB can guide adjuvant chemotherapy still needs further study.

Endoscopic management of delayed bleeding after polypectomy of small colorectal polyps: two or more clips may be safe.

Background: The resection of small colorectal polyps (≤10 mm) is routine for endoscopists. However, the management of one of its main complications, namely delayed (within 14 days) postpolypectomy bleeding (DPPB), has not been clearly demonstrated. We aimed to assess the role of coloscopy in the management of DPPB from small colorectal polyps and identify the associated factors for initial hemostatic success. Methods: We conducted a retrospective study of 69 patients who developed DPPB after the removal of colorectal polyps of ≤10 mm and underwent hemostatic colonoscopy at the Sixth Affiliated Hospital of Sun Yat-sen University (Guangzhou, China) between April 2013 and June 2021. Demographics, clinical variables, and colonoscopic features were collected independently. We applied univariate and multivariate analyses to assess factors associated with initial hemostatic success. Results: General colonoscopy without oral bowel preparation was successfully performed in all the patients, with a median duration of 23.9 (12.5-37.9) minutes. Among 69 patients, 62 (89.9%) achieved hemostasis after initial hemostatic colonoscopy and 7 (10.1%) rebled 2.7 ± 1.1 days after initial colonoscopic hemostasis and had rebleeding successfully controlled by one additional colonoscopy. No colonoscopy-related adverse events occurred. Multivariate analysis showed that management with at least two clips was the only independent prognostic factor for initial hemostatic success (odds ratio, 0.17; 95% confidence interval, 0.03-0.91; P = 0.04). All the patients who had at least two clips placed at the initial hemostatic colonoscopy required no further hemostatic intervention. Conclusions: Colonoscopy is a safe, effective, and not too time-consuming approach for the management of patients with DPPB of small colorectal polyps and management with the placement of at least two hemoclips may be beneficial.

Nomogram for predicting overall survival time of patients with stage IV colorectal cancer.

Background: Prognosis varies among stage IV colorectal cancer (CRC). Our study aimed to build a robust prognostic nomogram for predicting overall survival (OS) of patients with stage IV CRC in order to provide evidence for individualized treatment. Method: We collected the information of 16,283 patients with stage IV CRC in the Surveillance, Epidemiology, and End Results (SEER) database and then randomized these patients in a ratio of 7:3 into a training cohort and an internal validation cohort. In addition, 501 patients in the Sixth Affiliated Hospital of Sun Yat-sen University (Guangzhou, China) database were selected and used as an external validation cohort. Univariate and multivariate Cox analyses were used to screen out significant variables for nomogram establishment. The nomogram model was assessed using time-dependent receiver-operating characteristic curve (time-dependent ROC), concordance index (C-index), calibration curve, and decision curve analysis. Survival curves were plotted using the Kaplan-Meier method. Result: The C-index of the nomogram for OS in the training, internal validation, and external validation cohorts were 0.737, 0.727, and 0.655, respectively. ROC analysis and calibration curves pronounced robust discriminative ability of the model. Further, we divided the patients into a high-risk group and a low-risk group according to the nomogram. Corresponding Kaplan-Meier curves showed that the prediction of the nomogram was consistent with the actual practice. Additionally, model comparisons and decision curve analysis proved that the nomogram for predicting prognosis was significantly superior to the tumor-node-metastasis (TNM) staging system. Conclusions: We constructed a nomogram to predict OS of the stage IV CRC and externally validate its generalization, which was superior to the TNM staging system.

Development and validation of an individualized gene expression-based signature to predict overall survival in metastatic colorectal cancer.

BACKGROUND: Metastatic colorectal cancer (mCRC) is a heterogeneous disease. Predictive biomarkers are in great demand to optimize patient selection at high risk for death and to provide a novel insight into potential targeted therapy. METHODS: The present study retrospectively analyzed the gene expression profiles of tumor tissue samples from 4 public CRC cohorts, including 1 RNA-Seq data set from The Cancer Genome Atlas (TCGA) CRC cohort and 3 microarray data sets from GEO. Prognostic analysis was performed to test the predictive value of prognostic gene signature. RESULTS: Of 192 patients, 108 patients (56.3%) were men and median age was 65 years. A prognostic gene signature that consisted of 15 unique genes was generated in the discovery cohort. In the meta-validation cohorts, the signature significantly classified patients into high-risk and low-risk groups with regard to overall survival (OS) in mCRC patients with advanced stage disease and remained as an independent prognostic marker in multivariable analysis (1.57; 95% CI: 1.16-2.11; P=0.003) after adjusting for clinical parameters and molecular types. Gene Set Enrichment Analysis showed that several biological processes, including angiogenesis (P<0.001), epithelial mesenchymal transit (P<0.001) and inflammatory response (P=0.001), were enriched among this prognostic gene signature. CONCLUSIONS: The proposed prognostic gene signature is a promising prognostic tool to estimate OS in mCRC. Prospective larger studies to examine the clinical utility of the biomarkers to guide individualized treatment of mCRC are warranted.

Laparoscopic Surgery for Complex Crohn's Disease: A Meta-Analysis.

Aim: There is still no consensus on whether laparoscopic surgery can be routinely recommended as a safe approach for complex Crohn's disease (CD). Methods: PubMed, Embase, and Cochrane library databases were searched (up to February 2019). Comparative studies reporting laparoscopic surgery for complex CD (LC group) comparing with simple CD (LS group) were included. The outcomes were blood loss, operative time, conversion rate, length of hospital stay, postoperative complications, and reoperation rate within 30 days after surgery. Results: Thirteen retrospective studies with 1120 participants were included. The LC group has significantly more blood loss (weighted mean difference [WMD] 43.64 mL; 95% confidence interval (CI) 8.37-78.91; P = .020), longer operative time (WMD 17.59 minutes; 95% CI 6.38-28.81; P = .002), higher conversion rate (WMD 2.04%; 95% CI 1.43-2.91; P < .001), and longer length of hospital stay (WMD 0.86 day; 95% CI 0.53-1.19; P < .001). Overall postoperative complication rates (WMD 0.98; 95% CI 0.71-1.34; P = .90) did not differ significantly between the 2 groups. Conclusions: LC is safe and feasible with comparable postoperative complications, although there is a more blood loss, longer operative time, higher conversion rate, and longer length of hospital stay.

Preoperative assessment of lymph node metastasis in clinically node-negative rectal cancer patients based on a nomogram consisting of five clinical factors.

BACKGROUND: Currently, reliable approaches for accurate assessment of lymph node metastases (LNM), which is an important indication of preoperative chemoradiotherapy (CRT), are not available for clinically node-negative rectal cancer patients. This study aims to identify clinical factors associated with LNM and to establish a nomogram for LNM prediction in clinically node-negative rectal cancer patients. METHODS: The least absolute shrinkage and selection operator (LASSO) aggression and multivariate logistic regression analyses were applied to identify clinical factors associated with LNM. A nomogram was established to predict the probability of LNM in clinically node-negative rectal cancer patients based on the multivariate logistic regression model. RESULTS: Six potential risk factors were selected on the basis of LASSO aggression analysis, and five of them were identified as independent risk factors for LNM based on multivariate analysis, including MRI-reported tumor location, clinical T classification, MRI-reported tumor diameter, white blood cell count (WBC), and preoperative elevated tumor markers. A nomogram consisting of the five clinical factors was established and showed good discrimination. Decision curve analysis demonstrated that the established nomogram was reliable and accurate for LNM prediction in clinically node-negative rectal cancer patients. CONCLUSIONS: A nomogram based on five clinical factors, including MRI-reported tumor location, clinical T classification, MRI-reported tumor diameter, WBC, and preoperative elevated tumor markers, are useful for assessing LNM in clinically node-negative rectal cancer patients, which is important for preoperative CRT regimens.

Engulfment and Cell Motility Protein 1 Protects Against DSS-induced Colonic Injury in Mice via Rac1 Activation.

BACKGROUND AND AIMS: Mucosal healing is an emerging therapeutic goal that could result in clinical remission of inflammatory bowel disease [IBD]. We sought to determine the role of engulfment and cell motility protein 1 [ELMO1] in wound healing in vitro and in vivo and to investigate the underlying pathways. METHODS: RNA transcriptome sequencing was performed to detect the expression profiles of mRNA between inflamed tissues and corresponding non-inflamed tissues of IBD patients, followed by Gene Expression Omnibus [GEO] datasets and western blot analysis. The effects of ELMO1 overexpression or knockdown on cell migration and proliferation were determined. The dependence of these effects on Rac1 was assessed using a Rac1 inhibitor [NSC23766] and a Rac1 pull-down assay. We identified the underlying pathways involved by Gene Ontology [GO] analysis. A dextran sulphate sodium [DSS]-induced colitis model was established to evaluate the role of ELMO1 in colonic mucosal healing. RESULTS: ELMO1 was upregulated in inflamed tissues compared with corresponding non-inflamed tissues. ELMO1 overexpression increased cell migration in a Rac1-dependent manner. Depletion of ELMO1, or NSC23766 administration, abolished this effect. GO analysis revealed that ELMO1 overexpression preferentially affected pathways involved in cytoskeletal regulation and wound healing, which was demonstrated by enhanced F-actin staining and increased numbers of extending lamellipodia in cells overexpressing ELMO1. In DSS-induced colitis, systemic delivery of pSin-EF2-ELMO1-Pur attenuated colonic inflammation and promoted recovery from colonic injury. The protective effect of ELMO1 was dependent on Rac1 activation. CONCLUSIONS: ELMO1 protects against DSS-induced colonic injury in mice through its effect on epithelial migration via Rac1 activation.

Overexpression of G protein-coupled receptor 31 as a poor prognosticator in human colorectal cancer.

AIM: To investigate the expression of G protein-coupled receptor 31 (GPR31) and its clinical significance in human colorectal cancer (CRC). METHODS: To determine the association between the GPR31 expression and the prognosis of patients, we obtained paraffin-embedded pathological specimens from 466 CRC patients who underwent initial resection. A total of 321 patients from the First Affiliated Hospital of Sun Yat-sen University from January 1996 to December 2008 were included as a training cohort, whereas 145 patients from the Sixth Affiliated Hospital of Sun Yat-sen University from January 2007 to November 2008 were included as a validation cohort. We examined GPR31 expression levels in CRC tissues from two independent cohorts via immunohistochemical staining. All patients were categorized into either a GPR31 low expression group or a GPR31 high expression group. The clinicopathological factors and the prognosis of patients in the GPR31 low expression group and GPR31 high expression group were compared. RESULTS: We compared the clinicopathological factors and the prognosis of patients in the GPR31 low expression group and GPR31 high expression group. Significant differences were observed in the number of patients in pM classification between patients in the GPR31 low expression group and GPR31 high expression group (P = 0.007). The five-year survival and tumor-free survival rates of patients were 84.3% and 82.2% in the GPR31 low expression group, respectively, and both rates were 59.7% in the GPR31 high expression group (P < 0.05). Results of the Cox proportional hazard regression model revealed that GPR31 upregulation was associated with shorter overall survival and tumor-free survival of patients with CRC (P < 0.05). Multivariate analysis identified GPR31 expression in colorectal cancer as an independent predictive factor of CRC patient survival (P < 0.05). CONCLUSION: High GPR31 expression levels were found to be correlated with pM classification of CRC and to serve as an independent predictive factor of poor survival of CRC patients.

MicroRNA-143 Targets ATG2B to Inhibit Autophagy and Increase Inflammatory Responses in Crohn's Disease.

Background: Dysfunctional autophagy is recognized as a contributing factor in many chronic inflammatory diseases, including Crohn's disease (CD). Genetic analyses have found that microRNA (miRNA) levels are altered in the intestinal tissues of CD patients. Methods: The Sequencing Alternative Poly-Adenylation Sites (SAPAS) method was used to compare the 3' end of the total mRNA sequence of 3 surgical specimens of CD patients (including inflamed tissues and corresponding noninflamed tissues in each case). The levels of autophagy-related 2B (ATG2B), LC3, and miR-143 were compared between inflamed tissues and noninflamed tissues using immunoblot and quantitative reverse transcription polymerase chain reaction. Luciferase assays were used to verify the interactions between miR-143 and ATG2B. Autophagy was measured by immunoblot analyses of LC3 and transmission electron microscopy. Inflammatory cytokines and IκBα were analyzed to evaluate the effect of miR-143 on inflammatory response. Results: The tandem repeat 3'-UTR of ATG2B was longer in inflamed tissues than in corresponding noninflamed tissues and contained an miR-143 target site. miR-143 expression was elevated, whereas ATG2B and LC3-II were downregulated in inflamed tissues. The direct interaction between miR-143 and ATG2B was verified by a 3'-UTR dual-luciferase reporter assay. Constitutive expression of miR-143 or depletion of ATG2B in cultured intestinal epithelial cells inhibited autophagy, reduced IκBα levels, and increased inflammatory responses. Conclusions: miR-143 may induce bowel inflammation by regulating ATG2B and autophagy, suggesting that miR-143 might play a critical role in the development of CD. Therefore, miR-143 could be a promising novel target for gene therapy in CD patients.

Male gender is associated with an increased risk of anastomotic leak in rectal cancer patients after total mesorectal excision.

BACKGROUND: The impact of a patient's gender on the development of anastomotic leak (AL) in rectal cancer patients following total mesorectal excision (TME) remains controversial. The aim of this study was to evaluate the association between patients' gender and the risk of AL. METHODS: All rectal cancer patients following TME with a primary anastomosis during the study period from 2010 to 2014 were examined. Comparisons of the post-operative AL incidence rate between male and female patients were performed. RESULTS: Of all patients examined (n = 956), 587 (61.4%) were males and 369 (38.6%) were females. Male patients were more likely to have a history of smoking and drinking alcohol, but less likely to have a history of abdominal surgery compared to female patients. A higher incidence rate of pre-operative bowel obstruction and larger tumor volume in male patients was observed in our study. Of all the patients, 81 (8.5%) developed post-operative AL. More male patients (n = 62, 10.6%) suffered from AL than females (n = 19, 5.1%) (P = 0.003). Multivariate logistic regression analyses confirmed the association between male gender and AL [odds ratio (OR): 2.41, 95% confidence interval (CI): 1.37-4.23, P = 0.002]. Similar results were also obtained in patients who underwent laparoscopic TME (OR: 2.11, 95% CI: 1.15-3.89, P = 0.016). CONCLUSIONS: Male patents were found to have an increased risk for AL following TME with a primary anastomosis. A temporary protecting stoma may help to protect the anastomosis and lessen the risk for AL especially in male patients.

[Lymph nodes distribution and metastatic pattern of ultra-low rectal cancer after neoadjuvant therapy].

OBJECTIVE: To investigate the lymph nodes distribution and metastatic pattern of the ultra-low rectal cancer after neoadjuvant therapy. METHODS: A total of 21 rectal cancer gross specimen after neoadjuvant therapy and 23 rectal cancer gross specimen without neoadjuvant therapy were investigated by whole mount section and tissue microarray techniques with CK20. All the patients were treated by abdominoperineal resection. RESULTS: There were 138 lymph nodes retrieved from the mesorectum in the neoadjuvant group including 39 metastatic lymph nodes and 12 micro-metastatic lymph nodes. Among these nodes, there were 7 rectal cancer cases with lymph nodes and 2 cases with micro-metastatic lymph nodes, and 6 cases had pathological complete remission. There were 415 lymph nodes retrieved from the mesorectum in the group without neoadjuvant therapy including 169 metastatic lymph nodes and 59 micro-metastatic lymph nodes. Among these nodes, there were 12 rectal cancer cases with lymph nodes and 4 cases with micro-metastatic lymph nodes. The proportions of metastatic lymph nodes in outer zone between the two groups were 21.5% and 29.0%, and those in pre-zone were 17.6% and 17.2% respectively. The ratio of metastatic lymph nodes in ischiorectal fossa between the two groups were 25.0% vs. 22.2% respectively. The rate of metastatic or micro-metastatic lymph nodes cases between the two groups were 4.8% vs. 13.0% respectively. CONCLUSIONS: The lymph nodes distribution and metastatic pattern of the ultra-low rectal cancer are affected by neoadjuvant therapy. The proportions of the anal sphincter invasion and metastatic or micro-metastatic lymph nodes in ischiorectal fossa are lower after neoadjuvant therapy. Abdominoperineal resection as the standard treatment of the ultra-low rectal cancer after neoadjuvant therapy should be re-evaluated.

Enteral nutrition is associated with a decreased risk of surgical intervention in Crohn's disease patients with spontaneous intra-abdominal abscess

Background: The impact of enteral nutrition (EN) on surgical risk in Crohn’s disease (CD) patients suffering from spontaneous intra-abdominal abscess (IAA) was evaluated. Methods: CD patients diagnosed with spontaneous IAA from 2008 to 2015 were included in the study. The impact of EN on surgical risk was evaluated using both univariate and multivariate analyses. Results: A total of 87 patients were enrolled, 66 (75.9%) were male. The mean age at the development of an abscess was 30.2 ± 10.1 years and the median duration of illness from CD diagnosis until the development of an abscess was three (2-6) years. After a median follow-up of 1.9 (1.1-2.9) years, surgical intervention was performed in 42 patients (48.3%). Patients treated with EN were less likely to require surgical intervention (26.1% vs 56.3%, p = 0.01). Multivariate analysis showed that EN was an independent protective factor for the risk of surgery with a hazard ratio of 0.27 (95% confidence interval: 0.11-0.65, p = 0.004) after adjusting for abdominal pain, history of abdominal surgery, concomitant intestinal stenosis and prior use of antibiotics within three months. Conclusions: Surgical intervention is common for CD patients with IAA. Appropriate application of EN may help obviate the need for surgical treatment (AU)

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