Long-term outcomes after endoscopic removal of malignant colorectal polyps:Results from a 10-year cohort

BACKGROUND Choosing an optimal post-polypectomy management strategy of malignant colorectal polyps is challenging,and evidence regarding a surveillance-only strategy is limited.AIM To evaluate long-term outcomes after endoscopic removal of malignant colorectal polyps.METHODS A single-center retrospective cohort study was conducted to evaluate outcomes after endoscopic removal of malignant colorectal polyps between 2010 and 2020.Residual disease rate and nodal metastases after secondary surgery and local and distant recurrence rate for those with at least 1 year of follow-up were invest-igated.Event rates for categorical variables and means for continuous variables with 95%confidence intervals were calculated,and Fisher’s exact test and Mann-Whitney test were performed.Potential risk factors of adverse outcomes were RESULTS In total,135 lesions(mean size:22.1 mm;location:42%rectal)from 129 patients(mean age:67.7 years;56%male)were enrolled.The proportion of pedunculated and non-pedunculated lesions was similar,with en bloc resection in 82%and 47%of lesions,respectively.Tumor differentiation,distance from resection margins,depth of submucosal invasion,lymphovascular invasion,and budding were reported at 89.6%,45.2%,58.5%,31.9%,and 25.2%,respectively.Residual tumor was found in 10 patients,and nodal metastasis was found in 4 of 41 patients who underwent secondary surgical resection.Univariate analysis identified piecemeal resection as a risk factor for residual malignancy(odds ratio:1.74;P=0.042).At least 1 year of follow-up was available for 117 lesions from 111 patients(mean follow-up period:5.59 years).Overall,54%,30%,30%,11%,and 16%of patients presented at the 1-year,3-year,5-year,7-year,and 9-10-year surveillance examinations.Adverse outcomes occurred in 9.0%(local recurrence and dissemination in 4 patients and 9 patients,respectively),with no difference between patients undergoing secondary surgery and surveillance only.CONCLUSION Reporting of histological features and adherence to surveillance colonoscopy needs improvement.Long-term adverse outcome rates might be higher than previously reported,irrespective of whether secondary surgery was performed.

Association between triglyceride-glucose index and colorectal polyps:A retrospective cross-sectional study

BACKGROUND Colorectal polyps(CPs)are frequently occurring abnormal growths in the colorectum,and are a primary precursor of colorectal cancer(CRC).The triglyceride-glucose(TyG)index is a novel marker that assesses metabolic health and insulin resistance,and has been linked to gastrointestinal cancers.AIM To investigate the potential association between the TyG index and CPs,as the relation between them has not been documented.METHODS A total of 2537 persons undergoing a routine health physical examination and colonoscopy at The First People's Hospital of Kunshan,Jiangsu Province,China,between January 2020 and December 2022 were included in this retrospective cross-sectional study.After excluding individuals who did not meet the eligibility criteria,descriptive statistics were used to compare characteristics between patients with and without CPs.Logistic regression analyses were conducted to determine the associations between the TyG index and the prevalence of CPs.The TyG index was calculated using the following formula:Ln[triglyceride(mg/dL)×glucose(mg/dL)/2].The presence and types of CPs was determined based on data from colonoscopy reports and pathology reports.RESULTS A nonlinear relation between the TyG index and the prevalence of CPs was identified,and exhibited a curvilinear pattern with a cut-off point of 2.31.A significant association was observed before the turning point,with an odds ratio(95% confidence interval)of 1.70(1.40,2.06),P<0.0001.However,the association between the TyG index and CPs was not significant after the cut-off point,with an odds ratio(95% confidence interval)of 0.57(0.27,1.23),P=0.1521.CONCLUSION Our study revealed a curvilinear association between the TyG index and CPs in Chinese individuals,suggesting its potential utility in developing colonoscopy screening strategies for preventing CRC.

Artificial intelligence for characterization of diminutive colorectal polyps:A feasibility study comparing two computer-aided diagnosis systems

BACKGROUND Artificial intelligence(AI)has potential in the optical diagnosis of colorectal polyps.AIM To evaluate the feasibility of the real-time use of the computer-aided diagnosis system(CADx)AI for ColoRectal Polyps(AI4CRP)for the optical diagnosis of diminutive colorectal polyps and to compare the performance with CAD EYE^(TM)(Fujifilm,Tokyo,Japan).CADx influence on the optical diagnosis of an expert endoscopist was also investigated.METHODS AI4CRP was developed in-house and CAD EYE was proprietary software provided by Fujifilm.Both CADxsystems exploit convolutional neural networks.Colorectal polyps were characterized as benign or premalignant and histopathology was used as gold standard.AI4CRP provided an objective assessment of its characterization by presenting a calibrated confidence characterization value(range 0.0-1.0).A predefined cut-off value of 0.6 was set with values<0.6 indicating benign and values≥0.6 indicating premalignant colorectal polyps.Low confidence characterizations were defined as values 40%around the cut-off value of 0.6(<0.36 and>0.76).Self-critical AI4CRP’s diagnostic performances excluded low confidence characterizations.RESULTS AI4CRP use was feasible and performed on 30 patients with 51 colorectal polyps.Self-critical AI4CRP,excluding 14 low confidence characterizations[27.5%(14/51)],had a diagnostic accuracy of 89.2%,sensitivity of 89.7%,and specificity of 87.5%,which was higher compared to AI4CRP.CAD EYE had a 83.7%diagnostic accuracy,74.2%sensitivity,and 100.0%specificity.Diagnostic performances of the endoscopist alone(before AI)increased nonsignificantly after reviewing the CADx characterizations of both AI4CRP and CAD EYE(AI-assisted endoscopist).Diagnostic performances of the AI-assisted endoscopist were higher compared to both CADx-systems,except for specificity for which CAD EYE performed best.CONCLUSION Real-time use of AI4CRP was feasible.Objective confidence values provided by a CADx is novel and self-critical AI4CRP showed higher diagnostic performances compared to AI4CRP.

Is endoscopic mucosal resection-precutting superior to conventional methods for removing sessile colorectal polyps?

We reviewed a study that reported a comparative analysis of the effects of endoscopic mucosal resection(EMR)precutting and conventional EMR for removing non-pedunculated,10-20 mm sized colorectal polyps.We identified some statistical deficiencies in this study.In addition,we believe that the differences between the treatments failed to achieve significance,and therefore,further analysis is required.

Ability of lactulose breath test results to accurately identify colorectal polyps through the measurement of small intestine bacterial overgrowth

BACKGROUND While colorectal polyps are not cancerous,some types of polyps,known as adenomas,can develop into colorectal cancer over time.Polyps can often be found and removed by colonoscopy;however,this is an invasive and expensive test.Thus,there is a need for new methods of screening patients at high risk of developing polyps.AIM To identify a potential association between colorectal polyps and small intestine bacteria overgrowth(SIBO)or other relevant factors in a patient cohort with lactulose breath test(LBT)results.METHODS A total of 382 patients who had received an LBT were classified into polyp and non-polyp groups that were confirmed by colonoscopy and pathology.SIBO was diagnosed by measuring LBTderived hydrogen(H)and methane(M)levels according to 2017 North American Consensus recommendations.Logistic regression was used to assess the ability of LBT to predict colorectal polyps.Intestinal barrier function damage(IBFD)was determined by blood assays.RESULTS H and M levels revealed that the prevalence of SIBO was significantly higher in the polyp group than in the non-polyp group(41%vs 23%,P<0.01;71%vs 59%,P<0.05,respectively).Within 90 min of lactulose ingestion,the peak H values in the adenomatous and inflammatory/hyperplastic polyp patients were significantly higher than those in the non-polyp group(P<0.01,and P=0.03,respectively).In 227 patients with SIBO defined by combining H and M values,the rate of IBFD determined by blood lipopolysaccharide levels was significantly higher among patients with polyps than those without(15%vs 5%,P<0.05).In regression analysis with age and gender adjustment,colorectal polyps were most accurately predicted with models using M peak values or combined H and M values limited by North American Consensus recommendations for SIBO.These models had a sensitivity of≥0.67,a specificity of≥0.64,and an accuracy of≥0.66.CONCLUSION The current study made key associations among colorectal polyps,SIBO,and IBFD and demonstrated that LBT has moderate potential as an alternative noninvasive screening tool for colorectal polyps.

Potential applications of artificial intelligence in colorectal polyps and cancer: Recent advances and prospects

Since the advent of artificial intelligence(AI)technology,it has been constantly studied and has achieved rapid development.The AI assistant system is expected to improve the quality of automatic polyp detection and classification.It could also help prevent endoscopists from missing polyps and make an accurate optical diagnosis.These functions provided by AI could result in a higher adenoma detection rate and decrease the cost of polypectomy for hyperplastic polyps.In addition,AI has good performance in the staging,diagnosis,and segmentation of colorectal cancer.This article provides an overview of recent research focusing on the application of AI in colorectal polyps and cancer and highlights the advances achieved.

Underwater vs conventional endoscopic mucosal resection in treatment of colorectal polyps:A meta-analysis

BACKGROUND Underwater endoscopic mucosal resection(UEMR)of colorectal lesions is emerging as an alternative method to conventional endoscopic mucosal resection(EMR);however,it is still controversial whether there is a difference in the effectiveness between UEMR and EMR.AIM To evaluate the effectiveness and safety of UEMR in the treatment of colorectal polyps.METHODS Clinical studies comparing the effectiveness or safety of UEMR in the treatment of colorectal polyps were searched in medical databases,including Pub Med,Embase,Cochrane Library,CNKI,and Wanfang Data,monographs,theses,and papers presented at conferences.Statistical analyses were performed using Revman 5.3 software.RESULTS Seven non-randomized controlled trials and one randomized controlled trial met the inclusion criteria.In total,1382 patients(1511 polyps)were included in the study,including 722 who received UEMR and 789 who received EMR.In the UEMR and EMR groups,the en bloc resection rates were 85.87%and 73.89%,respectively,with a relative risk(RR)value of 1.14(95%confidence interval[CI]:1.01-1.30;P<0.05).In the sub-group analysis,the en bloc resection rate showed no statistically significant difference between the EMR and UEMR groups for polyps less than 20 mm in diameter.However,a statistically significant difference was found between the EMR and UEMR groups for polyps equal to or greater than 20 mm in diameter.The post-endoscopic resection recurrence rates at 3-6 mo of the UEMR and EMR groups were 3.26%and 15.17%,respectively,with an RR value of 0.27(95%CI:0.09-0.83;P<0.05).The post-endoscopic resection recurrence rates of UEMR and EMR at 12 mo were 6.25%and 14.40%,respectively,with an RR value of 0.43(95%CI:0.20-0.92;P<0.05).Additionally,the incidence of adverse events was 8.17%and 6.21%,respectively,with an RR value of 1.07(95%CI:0.50-2.30;P>0.05).CONCLUSION UEMR is an effective technique for colorectal polyps and appears to have some advantages over EMR,particularly with regard to some treatment outcomes.

Effect of cold snare polypectomy for small colorectal polyps

BACKGROUND Colorectal cancer remains a considerable challenge in healthcare nowadays.Approximately 60%-80%of colorectal cancer is caused by intestinal polyps,and resection of intestinal polyps has been proved to reduce the incidence of colorectal cancer.The vast majority of intestinal polyps can be found during colonoscopy and removed endoscopically.Therefore,more attention has been paid to the development of endoscopic resection of intestinal polyps.In this study,we compared the efficacy and safety of cold snare polypectomy(CSP)and hot snare polypectomy(HSP).AIM To investigate the efficacy and safety of CSP and HSP for colorectal polyps.METHODS Between January and December 2020,301 patients with colorectal polyps 4-9 mm in diameter were treated with endoscopic therapy in our hospital,and were divided into the CSP group(n=154)and HSP group(n=147).The operating time,incidence of bleeding and perforation,use of titanium clips,and complete resection rate were compared between the two groups.RESULTS We included 249 patients(301 polyps).No differences in gender,age,and polyp size,location,shape and type were observed between the CSP and HSP groups,and the resection rates in these two groups were 93.4%and 94.5%,respectively,with no significant difference.The use of titanium clips was 15.6%and 95.9%,the operating time was 3.2±0.5 min and 5.6±0.8 min,the delayed bleeding rate was 0%and 2.0%,and delayed perforation was 0%and 0.7%,in the CSP and HSP groups,respectively.CONCLUSIONFor sessile colorectal polyps < 10 mm, CSP had the same resection rate of impaired tissue integrityas traditional HSP had. The rate of complications was lower in the CSP group. CSP is a safe andeffective method for polypectomy.

Optical diagnosis of colorectal polyps using convolutional neural networks

Colonoscopy remains the gold standard investigation for colorectal cancer screening as it offers the opportunity to both detect and resect pre-malignant and neoplastic polyps.Although technologies for image-enhanced endoscopy are widely available,optical diagnosis has not been incorporated into routine clinical practice,mainly due to significant inter-operator variability.In recent years,there has been a growing number of studies demonstrating the potential of convolutional neural networks(CNN)to enhance optical diagnosis of polyps.Data suggest that the use of CNNs might mitigate the inter-operator variability amongst endoscopists,potentially enabling a“resect and discard”or“leave in”strategy to be adopted in real-time.This would have significant financial benefits for healthcare systems,avoid unnecessary polypectomies of non-neoplastic polyps and improve the efficiency of colonoscopy.Here,we review advances in CNN for the optical diagnosis of colorectal polyps,current limitations and future directions.

Endoscopic mucosal resection-precutting vs conventional endoscopic mucosal resection for sessile colorectal polyps sized 10-20 mm

BACKGROUND The optimal method to remove sessile colorectal lesions sized 10-20 mm remains uncertain.Piecemeal and incomplete resection are major limitations in current practice,such as endoscopic mucosal resection(EMR)and cold or hot snare polypectomy.Recently,EMR with circumferential precutting(EMR-P)has emerged as an effective technique,but the quality of current evidence in comparative studies of conventional EMR(CEMR)and EMR-P is limited.AIM To investigate whether EMR-P is superior to CEMR in removing sessile colorectal polyps.METHODS This multicenter randomized controlled trial involved seven medical institutions in China.Patients with colorectal polyps sized 10-20 mm were enrolled and randomly assigned to undergo EMR-P or CEMR.EMR-P was performed following submucosal injection,and a circumferential mucosa incision(precutting)was conducted using a snare tip.Primary outcomes included a comparison of the rates of en bloc and R0 resection,defined as one-piece resection and one-piece resection with histologically assessed clear margins,respectively.RESULTS A total of 110 patients in the EMR-P group and 110 patients in the CEMR group were finally evaluated.In the per-protocol analysis,the proportion of en bloc resections was 94.3%[95%confidence interval(CI):88.2%-97.4%]in the EMR-P group and 86%(95%CI:78.2%-91.3%)in the CEMR group(P=0.041),while subgroup analysis showed that for lesions>15 mm,EMR-P also resulted in a higher en bloc resection rate(92.0%vs 58.8%P=0.029).The proportion of R0 resections was 81.1%(95%CI:72.6%-87.4%)in the EMR-P group and 76.6%(95%CI:68.8%-84.4%)in the CEMR group(P=0.521).The EMR-P group showed a longer median procedure time(6.4 vs 3.0 min;P<0.001).No significant difference was found in the proportion of patients with adverse events(EMR-P:9.1%;CEMR:6.4%;P=0.449).CONCLUSION In this study,EMR-P served as an alternative to CEMR for removing nonpedunculated colorectal polyps sized 10-20 mm,particularly polyps>15 mm in diameter,with higher R0 and en bloc resection rates and without increasing adverse events.However,EMR-P required a relatively longer procedure time than CEMR.Considering its potential benefits for en bloc and R0 resection,EMR-P may be a promising technique in colorectal polyp resection.

Analysis of 234 cases of colorectal polyps treated by endoscopic mucosal resection

BACKGROUND Colorectal polyps refer to all neoplasms that protrude into the intestinal cavity.Researchers believe that 50%-70%of colorectal cancers originate from adenomatous polyps.AIM To investigate the endoscopic morphologic features,pathologic types,and clinical situation;evaluate the efficacy and safety of endoscopic mucosal resection(EMR);and guide clinicians in their daily practice.METHODS Two hundred thirty-four patients who underwent EMR in our hospital from January 1,2018 to December 31,2019 were recruited.Data including sex,age,endoscopic morphology of the polyps,and pathological characteristics were analyzed among groups.RESULTS A total of 295 polyps were resected from the 234 subjects enrolled in the study,of which 4(1.36%)were Yamada type I.There were 75(25.42%)type II,101(34.24%)type III,and 115(38.98%)type IV adenomas.Among them,41 were nonadenomas,110 were low-risk adenomas,139 were high-risk adenomas,and 5 were carcinomas.The differences in distribution were not statistically significant,with P values greater than 0.05.The risk of cancer significantly increased for polyps≥1 cm in diameter(c2=199.825,P=0.00).Regarding the endoscopic morphological features,congestion,erosion,and lobulation were more common on the surface morphology of high-risk adenomas and cancerous polyps(c2=75.257,P=0.00),and most of them were Yamada types III and IV.In all,6 of the 295 polyps could not be removed completely,with a one-time resection rate of 97.97%.There were two cases of postoperative bleeding and no cases of perforation,with an overall complication rate of 0.09%.CONCLUSION Colorectal polyps ranging from non-adenomatous polyps,low-risk adenomas,and high-risk adenomas to adenocarcinomas each has their own endoscopic features,while EMR,as a mature intervention,has good safety and operability and should be promoted clinically,especially at the primary care level.

Real-world local recurrence rate after cold polypectomy in colorectal polyps less than 10 mm using propensity score matching

BACKGROUND Cold polypectomy(CP)is a simple and safe procedure for polyps less than 10 mm in size;however,there is concern about local recurrence following CP because of unidentified margins of excised specimens and the lack of tumor suppression effect by coagulation.Some clinical trials have evaluated local persistent recurrence;their results suggest that a higher rate of local recurrence has not been documented so far.There were few reports that observed the course over long periods of time after CP in clinical practice.AIM To evaluate the presence of local recurrence following CP and hot polypectomy(HP)using propensity score matching.METHODS We analyzed 275 patients who underwent polypectomy for non-pedunculated colorectal polyps less than 10 mm(959 Lesions)between October 2016 and 2017 and underwent follow-up endoscopy subsequently.We divided them into the CP group(706 Lesions),wherein CP was performed,and the HP group(253 Lesions),wherein HP was performed.Using propensity score matching,we extracted 215 Lesions in each group and evaluated the local recurrence and content of CP in the real clinic and adverse events using medical records.RESULTS After propensity score matching,there were no significant differences in the patients’and their endoscopic background(age,use of antithrombotics,indications,size,morphology,location of polyps,and polypectomy device)between the groups.The mean duration between colorectal polypectomy and the next follow-up colonoscopy was 17.5±7.1(range,6-39)mo in the CP group and 15.7±6.0(range,6-35)mo in the HP group,which was significantly longer in the CP group(P=0.005).The local recurrence rate was 0.93%in the CP group and 0.93%in the HP group,without a significant difference(P=0.688).Additionally,no differences were observed in the macroscopic en bloc resection rate,histopathological complete resection rate,and pathological results between the groups.Adverse events did not occur in either group.CONCLUSION Local recurrence after CP was equivalent to that following HP in clinical practice.CP is useful and safe in the treatment of non-pedunculated polyps of less than 10 mm.

Mucosa color and size may indicate malignant transformation of chicken skin mucosa-positive colorectal neoplastic polyps

BACKGROUND Lipid metabolism reprogramming is suspected to exist in pre-cancerous lesions,including colorectal adenoma.Screening colonoscopy frequently reveals chicken skin mucosa(CSM;white or yellow-white speckled mucosa)surrounding colo-rectal polyps,caused by macrophages engulfing and accumulating the lipids decomposed by colon cells or adjacent tumors.CSM-positive colorectal polyps are associated with various diseases;however,their prognosis varies greatly.Cold snare polypectomy is commonly used to resect lesions up to 10 to 15 mm in diameter without signs of submucosal invasion but is controversial for CSM-positive colorectal polyps.Improved imaging is required to diagnose and treat CSM-positive colorectal polyps.METHODS This retrospective cohort study included 177 patients with CSM-positive colorectal polyps diagnosed using endoscopy.All patient-related information was extracted from the Goldisc soft-clinic DICOM system or electronic medical record system.Based on the pathological results,patients were classified as non-neoplastic polyps(five juvenile polyps),neoplastic polyps,non-invasive high-grade neoplasia(NHGN),or submucosal invasive carcinoma(SM stage cancer).We analyzed and compared the clinical features,suspected risk factors for malignant transformation of neoplastic polyps,and early infiltration of sub-mucosal carcinoma.RESULTS The diameters of NHGN and SM polyps were much smaller than those of neoplastic polyps.Most NHGN polyps had a deeper red mucosal color.On logistic regression analyses,diameter and deeper red mucosal color were independent risk factors for malignant transformation of neoplastic polyps.Type 1 CSM was more common in high-grade intraepithelial neoplasia and SM;type 2 CSM was more common in neoplastic polyps.Logistic regression analyses revealed no significant differences in the malignant transformation of neoplastic polyps or early submucosal invasion of CSM-positive colorectal cancer.Changes in the CSM mucosa surrounding neoplastic polyps and submucosal invasion of colorectal cancer disappeared within 12 months.No tumor recurrence was found during either partial or complete endoscopic resection of the CSM.CONCLUSION CSM-positive colorectal polyps>1 cm in diameter or with deeper red mucosa may be related to NHGN.Resection of CSM surrounding colorectal adenomas did not affect tumor recurrence.

Transient elastography with controlled attenuation parameter for the diagnosis of colorectal polyps in patients with nonalcoholic fatty liver disease

BACKGROUND The severity of nonalcoholic fatty liver disease(NAFLD)and lipid metabolism are related to the occurrence of colorectal polyps.Liver-controlled attenuation parameters(liver-CAPs)have been established to predict the prognosis of hepatic steatosis patients.AIM To explore the risk factors associated with colorectal polyps in patients with NAFLD by analyzing liver-CAPs and establishing a diagnostic model.METHODS Patients who were diagnosed with colorectal polyps in the Department of Gastroenterology of our hospital between June 2021 and April 2022 composed the case group,and those with no important abnormalities composed the control group.The area under the receiver operating characteristic curve was used to predict the diagnostic efficiency.Differences were considered statistically significant when P<0.05.RESULTS The median triglyceride(TG)and liver-CAP in the case group were significantly greater than those in the control group(mmol/L,1.74 vs 1.05;dB/m,282 vs 254,P<0.05).TG and liver-CAP were found to be independent risk factors for colorectal polyps,with ORs of 2.338(95%CI:1.154–4.733)and 1.019(95%CI:1.006–1.033),respectively(P<0.05).And there was no difference in the diagnostic efficacy between liver-CAP and TG combined with liver-CAP(TG+CAP)(P>0.05).When the liver-CAP was greater than 291 dB/m,colorectal polyps were more likely to occur.CONCLUSION The levels of TG and liver-CAP in patients with colorectal polyps are significantly greater than those patients without polyps.Liver-CAP alone can be used to diagnose NAFLD with colorectal polyps.

Endoscopic management of colorectal polyps

Colorectal polyps are premalignant lesions in the lower gastrointestinal tract.Endoscopic polypectomy is an effective strategy to prevent colorectal cancer morbidity and more invasive procedures.Techniques for the endoscopic resection of polyps keep evolving,and endoscopists are required to perform the most appropriate technique for each polyp.In this review,we outline the evaluation and classification of polyps,update the recommendations for optimal treatment,describe the polypectomy procedures and their strengths/weaknesses,and discuss the promising innovative methods or concepts.

Endoscopic treatment of scarred polyps with a non-thermal device(Endorotor):A review of the literature

Endoscopic resection(ER)of colorectal polyps has become a daily practice in most endoscopic units providing a colorectal cancer screening program and requires the availability of local experts and high-end endoscopic devices.ER procedures have evolved over the past few years from endoscopic mucosal resection(EMR)to more advanced techniques,such as endoscopic submucosal dissection and endo-scopic full-thickness resection.Complete resection and disease eradication are the ultimate goals of ER-based techniques,and novel devices have been developed to achieve these goals.The EndoRotor®Endoscopic Powered Resection System(Interscope Medical,Inc.,Northbridge,Massachusetts,United States)is one such device.The EndoRotor is a powered resection tool for the removal of alimentary tract mucosa,including post-EMR persistent lesions with scarring,and has both CE Mark and FDA clearance.This review covers available published evidence documenting the usefulness of EndoRotor for the management of recurrent colorectal polyps.

Multi-Classification of Polyps in Colonoscopy Images Based on an Improved Deep Convolutional Neural Network

Achieving accurate classification of colorectal polyps during colonoscopy can avoid unnecessary endoscopic biopsy or resection.This study aimed to develop a deep learning model that can automatically classify colorectal polyps histologically on white-light and narrow-band imaging(NBI)colonoscopy images based on World Health Organization(WHO)and Workgroup serrAted polypS and Polyposis(WASP)classification criteria for colorectal polyps.White-light and NBI colonoscopy images of colorectal polyps exhibiting pathological results were firstly collected and classified into four categories:conventional adenoma,hyperplastic polyp,sessile serrated adenoma/polyp(SSAP)and normal,among which conventional adenoma could be further divided into three sub-categories of tubular adenoma,villous adenoma and villioustublar adenoma,subsequently the images were re-classified into six categories.In this paper,we proposed a novel convolutional neural network termed Polyp-DedNet for the four-and six-category classification tasks of colorectal polyps.Based on the existing classification network ResNet50,Polyp-DedNet adopted dilated convolution to retain more high-dimensional spatial information and an Efficient Channel Attention(ECA)module to improve the classification performance further.To eliminate gridding artifacts caused by dilated convolutions,traditional convolutional layers were used instead of the max pooling layer,and two convolutional layers with progressively decreasing dilation were added at the end of the network.Due to the inevitable imbalance of medical image data,a regularization method DropBlock and a Class-Balanced(CB)Loss were performed to prevent network overfitting.Furthermore,the 5-fold cross-validation was adopted to estimate the performance of Polyp-DedNet for the multi-classification task of colorectal polyps.Mean accuracies of the proposed Polyp-DedNet for the four-and six-category classifications of colorectal polyps were 89.91%±0.92%and 85.13%±1.10%,respectively.The metrics of precision,recall and F1-score were also improved by 1%∼2%compared to the baseline ResNet50.The proposed Polyp-DedNet presented state-of-the-art performance for colorectal polyp classifying on white-light and NBI colonoscopy images,highlighting its considerable potential as an AI-assistant system for accurate colorectal polyp diagnosis in colonoscopy.

Oral Glucose Combined with Short-Term Intravenous Nutrition for the Prevention of Hypoglycemia after Endoscopic Colorectal Polypectomy

Objective: To investigate the effect of oral glucose combined with short-term intravenous nutrition on the prevention of hypoglycemia after endoscopic colorectal polypectomy and to provide guidance for better management of such patients. Methods: 860 patients who underwent endoscopic colorectal polypectomy for colorectal polyps in the Department of Gastroenterology of the First Affiliated Hospital of Yangtze University from January 2020 to December 2021 were selected for the study. The patients were divided into experimental and control groups according to the random number table method, with 430 patients in each group. In the control group, 3 L of polyethylene glycol electrolyte dispersion was used for preoperative intestinal preparation and postoperative fasting was performed routinely for 24 h. Short-term intravenous nutrition support was provided by rehydration, and finger blood glucose was monitored at 1, 4, and 8 h after intravenous infusion or when there were symptoms such as panic and cold sweat;in the experimental group, oral glucose intervention was implemented on the basis of the control group. The incidence of postoperative hypoglycemia, quality of bowel preparation, and tolerance of patients during bowel preparation were compared between the 2 groups. Results: The incidence of postoperative blood glucose Conclusion: Based on the present study population, oral glucose combined with short-term intravenous nutrition can effectively prevent the incidence of hypoglycemia in patients after endoscopic colorectal polypectomy;however, this was limited to a single-center study and the number of cases was small.

Genetic heterogeneity of colorectal cancer and the microbiome

In 2020,the International Agency for Research on Cancer and the World Health Organization's GLOBOCAN database ranked colorectal cancer(CRC)as the third most common cancer in the world.Most cases of CRC(>95%)are sporadic and develop from colorectal polyps that can progress to intramucosal carcinoma and CRC.Increasing evidence is accumulating that the gut microbiota can play a key role in the initiation and progression of CRC,as well as in the treatment of CRC,acting as an important metabolic and immunological regulator.Factors that may determine the microbiota role in CRC carcinogenesis include inflammation,changes in intestinal stem cell function,impact of bacterial metabolites on gut mucosa,accumulation of genetic mutations and other factors.In this review,I discuss the major mechanisms of the development of sporadic CRC,provide detailed characteristics of the bacteria that are most often associated with CRC,and analyze the role of the microbiome and microbial metabolites in inflammation initiation,activation of proliferative activity in intestinal epithelial and stem cells,and the development of genetic and epigenetic changes in CRC.I consider longterm studies in this direction to be very important,as they open up new opportunities for the treatment and prevention of CRC.

Artificial intelligence for the early detection of colorectal cancer: A comprehensive review of its advantages and misconceptions

Colorectal cancer(CRC)was the second-ranked worldwide type of cancer during 2020 due to the crude mortality rate of 12.0 per 100000 inhabitants.It can be prevented if glandular tissue(adenomatous polyps)is detected early.Colonoscopy has been strongly recommended as a screening test for both early cancer and adenomatous polyps.However,it has some limitations that include the high polyp miss rate for smaller(<10 mm)or flat polyps,which are easily missed during visual inspection.Due to the rapid advancement of technology,artificial intelligence(AI)has been a thriving area in different fields,including medicine.Particularly,in gastroenterology AI software has been included in computer-aided systems for diagnosis and to improve the assertiveness of automatic polyp detection and its classification as a preventive method for CRC.This article provides an overview of recent research focusing on AI tools and their applications in the early detection of CRC and adenomatous polyps,as well as an insightful analysis of the main advantages and misconceptions in the field.