Guidelines for colonoscopy surveillance after polypectomy: a consensus update by the US Multi-Society Task Force on Colorectal Cancer and the American Cancer Society

Cellular and molecular events in colorectal cancer: biological mechanisms, cell death pathways, drug resistance and signalling network interactions

Colorectal cancer (CRC) is a leading cause of cancer-related deaths worldwide, affecting millions each year. It emerges from the colon or rectum, parts of the digestive system, and is closely linked to both genetic and environmental factors. In CRC, genetic mutations such as APC, KRAS, and TP53, along with epigenetic changes like DNA methylation and histone modifications, play crucial roles in tumor development and treatment responses. This paper delves into the complex biological underpinnings of CRC, highlighting the pivotal roles of genetic alterations, cell death pathways, and the intricate network of signaling interactions that contribute to the disease's progression. It explores the dysregulation of apoptosis, autophagy, and other cell death mechanisms, underscoring the aberrant activation of these pathways in CRC. Additionally, the paper examines how mutations in key molecular pathways, including Wnt, EGFR/MAPK, and PI3K, fuel CRC development, and how these alterations can serve as both diagnostic and prognostic markers. The dual function of autophagy in CRC, acting as a tumor suppressor or promoter depending on the context, is also scrutinized. Through a comprehensive analysis of cellular and molecular events, this research aims to deepen our understanding of CRC and pave the way for more effective diagnostics, prognostics, and therapeutic strategies.

Randomized Trial of Patient Outreach Approaches to De-implement Outdated Colonoscopy Surveillance Intervals

BACKGROUND AND AIMS

Guidelines now recommend patients with low-risk adenomas receive colonoscopy surveillance in 7-10 years and those with the previously recommended 5-year interval be re-evaluated. We tested 3 outreach approaches for transitioning patients to the 10-year interval recommendation.

METHODS

This was a 3-arm pragmatic randomized trial comparing telephone, secure messaging, and mailed letter outreach. The setting was Kaiser Permanente Northern California, a large integrated healthcare system. Participants were patients 54-70 years of age with 1-2 small (<10 mm) tubular adenomas at baseline colonoscopy, due for 5-year surveillance in 2022, without high-risk conditions, and with access to all 3 outreach modalities. Patients were randomly assigned to the outreach arm (telephone [n = 200], secure message [n = 203], and mailed letter [n = 201]) stratified by age, sex, and race/ethnicity. Outreach in each arm was performed by trained medical assistants (unblinded) communicating in English with 1 reminder attempt at 2-4 weeks. Participants could change their assigned interval to 10 years or continue their planned 5-year interval.

RESULTS

Sixty-day response rates were higher for telephone (64.5%) and secure messaging outreach (51.7%) vs mailed letter (31.3%). Also, more patients adopted the 10-year surveillance interval in the telephone (37.0%) and secure messaging arms (32.0%) compared with mailed letter (18.9%) and rate differences were significant for telephone (18.1%; 97.5% confidence interval: 8.3%-27.9%) and secure message outreach (13.1%; 97.5% confidence interval: 3.5%-22.7%) vs mailed letter outreach.

CONCLUSIONS

Telephone and secure messaging were more effective than mailed letter outreach for de-implementing outdated colonoscopy surveillance recommendations among individuals with a history of low-risk adenomas in an integrated healthcare setting. (ClinicalTrials.gov, Number: NCT05389397).

Survival trends for left and right sided colon cancer using population-based SEER database: A forty-five-year analysis from 1975 to 2019

BACKGROUND

Survival differences between left-sided colon cancer (LSCC) and right-sided colon cancer (RSCC) has been previously reported with mixed results, with various study periods not accounting for other causes of mortality.

PURPOSE

We sought to assess the trends in colon cancer cause- specific survival (CSS) and overall survival (OS) based on sidedness.

METHOD

Fine-Gray competing risk and Cox models were used to analyze Surveillance, Epidemiology, and End Results (SEER) population-based cohort from 1975 to 2019. Various interval periods were identified based on the timeline of clinical adoption of modern chemotherapy (1975-1989, interval period A; 1990-2004, B; and 2005-2019, C).

RESULTS

Of the 227,637 patients, 50.1% were female and 46.2% were RSCC. RSCC was more common for African Americans (51.5%), older patients (age ≥65; 51.4%), females (50.4%), while LSCC was more common among Whites (53.1%; p < 0.001), younger patients (age 18-49, 64.6%; 50-64, 62.3%; p < 0.001), males (58.1%; p < 0.001). The Median CSS for LSCC and RCC were 19.3 and 16.7 years respectively for interval period A (1975-1989). Median CSS for interval periods B and C were not reached (more than half of the cohort was still living at the end of the follow-up period). Adjusted CSS was superior for LSCC versus RSCC for the most recent interval period C (HR 0.89; 0.86-0.92; p < 0.001). LSCC consistently showed superior OS for all study periods. Stage stratification showed worse CSS for localized and regional LSCC in the earlier study periods, but the risk attenuated over time. However, left sided distant disease had superior CSS per stage for all interval periods. OS was better for LSCC irrespective of stage, with gradual improvement over time.

CONCLUSION

LSCC was associated with superior survival compared to right sided tumors. With the adoption of modern chemotherapy regimens, prognosis between LSCC and RSCC became more divergent in favor of LSCC. Colon cancer clinical trials should strongly consider tumor sidedness as an enrollment factor.

Gastrointestinal: Weight gain increases the risk of metachronous advanced colorectal neoplasm observed in post-polypectomy surveillance colonoscopy

BACKGROUND AND AIM

Although obesity is a known risk factor for colorectal neoplasms, the correlation between weight change and colorectal neoplasm is unclear. Thus, we aim to evaluate the association between weight change and advanced colorectal neoplasm (ACRN) recurrence during post-polypectomy surveillance colonoscopy.

METHODS

This retrospective cohort study included 7473 participants diagnosed with colorectal neoplasms between 2003 and 2010 who subsequently underwent surveillance colonoscopies until 2020. We analyzed the association between the risk of metachronous ACRN and weight change, defining stable weight as a weight change of <3% and weight gain as a weight increase of ≥3% from baseline during the follow-up period.

RESULTS

During a median 8.5 years of follow-up, 619 participants (8.3%) developed ACRN. Weight gain was reported as an independent risk factor for metachronous ACRN in a time-dependent Cox analysis. A weight gain of 3-6% and ≥6% had adjusted hazard ratios (AHRs) of 1.48 (95% confidence interval [CI]: 1.19-1.84) and 2.14 (95% CI: 1.71-2.69), respectively. Participants aged 30-49 and 50-75 years with weight gain of ≥6% showed AHRs of 2.88 (95% CI: 1.96-4.21) and 1.90 (95% CI: 1.43-2.51), respectively. In men and women, weight gain of ≥3% was significantly correlated with metachronous ACRN.

CONCLUSIONS

Weight gain is associated with an increased risk of metachronous ACRN. Furthermore, weight gain is associated with the recurrence of ACRN in both men and women regardless of age.

Development and Validation of a Deep Learning-Based Histologic Diagnosis System for Diagnosing Colorectal Sessile Serrated Lesions

OBJECTIVES

The histopathologic diagnosis of colorectal sessile serrated lesions (SSLs) and hyperplastic polyps (HPs) is of low consistency among pathologists. This study aimed to develop and validate a deep learning (DL)-based logical anthropomorphic pathology diagnostic system (LA-SSLD) for the differential diagnosis of colorectal SSL and HP.

METHODS

The diagnosis framework of the LA-SSLD system was constructed according to the current guidelines and consisted of 4 DL models. Deep convolutional neural network (DCNN) 1 was the mucosal layer segmentation model, DCNN 2 was the muscularis mucosa segmentation model, DCNN 3 was the glandular lumen segmentation model, and DCNN 4 was the glandular lumen classification (aberrant or regular) model. A total of 175 HP and 127 SSL sections were collected from Renmin Hospital of Wuhan University during November 2016 to November 2022. The performance of the LA-SSLD system was compared to 11 pathologists with different qualifications through the human-machine contest.

RESULTS

The Dice scores of DCNNs 1, 2, and 3 were 93.66%, 58.38%, and 74.04%, respectively. The accuracy of DCNN 4 was 92.72%. In the human-machine contest, the accuracy, sensitivity, and specificity of the LA-SSLD system were 85.71%, 86.36%, and 85.00%, respectively. In comparison with experts (pathologist D: accuracy 83.33%, sensitivity 90.91%, specificity 75.00%; pathologist E: accuracy 85.71%, sensitivity 90.91%, specificity 80.00%), LA-SSLD achieved expert-level accuracy and outperformed all the senior and junior pathologists.

CONCLUSIONS

This study proposed a logical anthropomorphic diagnostic system for the differential diagnosis of colorectal SSL and HP. The diagnostic performance of the system is comparable to that of experts and has the potential to become a powerful diagnostic tool for SSL in the future. It is worth mentioning that a logical anthropomorphic system can achieve expert-level accuracy with fewer samples, providing potential ideas for the development of other artificial intelligence models.

Publication trends and hotspots of colorectal adenoma during 2002-2022: a bibliometric and visualized analysis

Background

Prevention and treatment of colorectal adenoma (CRA) are great significant to reduce morbidity and mortality of colorectal cancer. Although there have been numerous studies on CRA recently, few publications utilized the bibliometrics to evaluate this field. The objective of current study was to provide a comprehensive analysis of the current state and frontier progress of CRA over the past 20 years.

Methods

The Web of Science Core Collection was utilized to extracted all studies of CRA during 2002-2022. Bibliometric tools including CiteSpace, VOSviewer, and the Online Analysis Platform of Literature Metrology were used for statistical analysis. CiteSpace and the Online Analysis Platform were used to evaluate the contributions of various countries/regions, institutions, authors, and journals in this field. Research hotspots and trends were identified through keywords and references analysis by VOSviewer and CiteSpace.

Results

2,268 publications from 2002 to 2022 in total were identified. The number of global publications in this field has increased annually. The USA was the most productive country, contributing nearly 30% of global publications. But in recent years, China's publications grew rapidly and had the highest citation strength. The most productive institutions was the National Cancer Institute. Baron JA from the USA was the most productive and the one of most co-cited authors. Cancer Epidemiology Biomarkers & Prevention had the highest number of publications and Gastroenterology was the most co-cited journals. Analysis of keywords clusters showed that "mechanism/pathophysiology", "risk factors and prevention", "colonoscopy screening and treatment", "metabolism", and "microbiota" were the major frontier topics and the main research directions.

Conclusions

CRA publications have shown a gradual upward trend in recent years, most of which have been published by developed countries. Developing countries should further focus on CRA research and transnational cooperation with developed countries in the future, in order to better improve the situation of the increasing morbidity and mortality of CRC. Baron JA was the most outstanding researcher in this field. More attention should be devoted to "pathogenesis of CRA", "less invasive diagnostic methods", "chemoprevention", and "screening and risk prediction of CRA including gut microbiome and metabolism", which will be frontiers in the future.

Use of surveillance colonoscopy among individuals with removal of high-risk polyps according to the US Multi-Society Task Force recommendations

BACKGROUND

Individuals with colorectal polypectomy are recommended to undergo surveillance colonoscopies at certain intervals to prevent subsequent colorectal cancer. Use of postpolypectomy surveillance according to the 2006 US Multi-Society Task Force (USMSTF) recommendations in an integrated health care system was investigated.

METHODS

Use of surveillance colonoscopies was prospectively assessed among 3691 patients with removal of high-risk polyps at a screening colonoscopy during 2007-2012 in the Mass General Brigham Colonoscopy Cohort. With the follow-up up to 2017, the compliance with, overuse, and underuse of postpolypectomy surveillance according to the 2006 USMSTF recommendations was assessed. Surveillance use according to demographic factors was also investigated.

RESULTS

During a median follow-up of 4.4 years (5th percentile, 95th percentile, 1.0, 9.9) 2360 (64%) patients had undergone a surveillance colonoscopy, among whom 758 (21%) were considered compliant with the USMSTF recommendations. A substantial underuse of surveillance colonoscopies of 62% was observed. Older age and lower income were associated with a higher incidence of underuse, whereas having a family history of colorectal cancer were associated with lower incidence of underuse. Overuse of surveillance colonoscopies was present in 17% of patients but showed no significant associations with demographic factors.

CONCLUSION

Substantial underuse of surveillance in patients with high-risk polyps was observed, particularly those with low income and older age. Efforts are needed to improve delivery and use of surveillance colonoscopy.

PLAIN LANGUAGE SUMMARY

The US Multi-Society Task Force recommends follow-up surveillance colonoscopy after polyp removal in the bowel, with intervals depending on the most severe findings. Adherence to surveillance recommendations in a large study with up to 10 years of follow-up among patients with high-risk polyps was investigated. Only 21% of patients adhered to the surveillance recommendations, whereas 62% showed delayed or no use of surveillance. Findings highlight the need for improved use of surveillance colonoscopy among patients at high risk of colorectal cancer.

Optimization of screening strategies for colorectal cancer based on fecal DNA and occult blood testing

BACKGROUND

Fecal DNA and occult blood testing have been gradually developed for colorectal cancer (CRC) screening. Comparison of different testing strategies for these methods in CRC screening is in urgent need. This study aims to examine the efficacy of different testing strategies including multi-target fecal DNA testing, qualitative and quantitative fecal immunoassay tests (FITs).

METHODS

Fecal samples were collected from patients diagnosed by colonoscopy. Tests using fecal DNA, quantitative FIT or qualitative FIT were performed on same fecal samples. Efficiency of different testing strategies within different populations was investigated.

RESULTS

For high-risk populations (CRC and advanced adenoma), the positive rate of the three methods alone was 74.3-80%; the positive predictive values (PPVs) ranged from 37.3% to 77.8%, and the negative predictive values (NPVs) ranged from 86.3% to 92.2%. For combined testing strategies, the positive rate was 71.4-88.6%, PPVs ranged from 38.3% to 86.2%, and NPVs ranged from 89.6% to 92.9%. Parallel fecal multi-target DNA test and quantitative FIT appears to be superior when using a combined testing strategy. For the normal population, no significant difference was identified in efficacy between these methods when used alone and in combination.

CONCLUSIONS

Single testing strategy among the three methods is more suitable for the general population screening, and the combined testing strategy is more suitable for high-risk populations screening. The use of different combination strategies may have superiority in CRC high-risk population screening, but cannot conclude significant differences which may be attributed to the small sample size, large samples controlled trials are needed.

Real-world compliance with the 2020 U.S. Multi-Society Task Force on Colorectal Cancer polypectomy surveillance guidelines: an observational study

BACKGROUND AND AIMS

Overuse of screening colonoscopy increases cost and procedural adverse events, but inadequate surveillance can miss the development of colorectal cancer. We measured compliance with the 2020 U.S. Multi-Society Task Force on Colorectal Cancer (USMSTF) polypectomy surveillance guidelines in clinical records and a survey.

METHODS

We performed a retrospective study comparing surveillance intervals for first-time average-risk colonoscopies with the 2020 USMSTF guidelines. Cases were analyzed from 3 intervals (March 2021 to May 2021, November 2021 to January 2022, and April 2022 to May 2022), collectively termed the postguideline period, and a baseline period from November 2019 to January 2020. Real-world compliance rates were compared with results of a survey conducted between November 2020 and February 2021.

RESULTS

Overall compliance was 48.9% among 532 colonoscopies, ranging from 8.3% for low-risk adenomas (LRAs), 88.3% for high-risk adenomas, 63.1% for sessile serrated polyps (SSPs), and 88.6% for hyperplastic polyps. Compliance for LRA increased from the baseline period (.8% vs 8.3%, P = .003), and 95.3% of nonadherent LRA cases followed the 2012 USMSTF guidelines. Compliance for LRAs was 18.6% among respondents who provided a compliant surveillance interval for LRAs in the survey. Noncompliance was associated with finishing training >10 years ago (odds ratio, 1.9; 95% confidence interval, 1.4-2.7) and performing over 800 colonoscopies annually (odds ratio, 2.0; 95% confidence interval, 1.5-2.6).

CONCLUSIONS

Adoption of the 2020 USMSTF surveillance guidelines remains low at 2 years. Further research into outcomes for patients with LRAs and SSPs may increase guideline adoption.

Risk of Metachronous Advanced Colorectal Neoplasia After Removal of Diminutive Versus Small Nonadvanced Adenomas: A Multicenter Study

BACKGROUND

Current postpolypectomy guidelines treat 1-9 mm nonadvanced adenomas (NAAs) as carrying the same level of risk for metachronous advanced colorectal neoplasia (ACRN).

AIMS

To evaluate whether small (6-9 mm) NAAs are associated with a greater risk of metachronous ACRN than diminutive (1-5 mm) NAAs.

METHODS

We retrospectively evaluated 10,060 index colonoscopies performed from July 2011 to June 2019. A total of 1369 patients aged ≥ 40 years with index NAAs and having follow-up examinations were categorized into 5 groups based on size and number of index findings: Group 1, ≤ 2 diminutive NAAs (n = 655); Group 2, ≤ 2 small NAAs (n = 529); Group 3, 3-4 diminutive NAAs (n = 78); Group 4, 3-4 small NAAs (n = 65); and Group 5, 5-10 NAAs (n = 42). Size was classified based on the largest NAA. ACRN was defined as finding an advanced adenoma or colorectal cancer at follow-up.

RESULTS

The absolute risk of metachronous ACRN increased from 7.2% in patients with all diminutive NAAs to 12.2% in patients with at least 1 small NAA (P = 0.002). Patients in Group 2 (adjusted odds ratio [AOR] 1.89; 95% confidence interval [CI], 1.21-2.95), Group 3 (AOR 2.40; 95% CI 1.78-4.90), Group 4 (AOR 2.77; 95% CI 1.35-5.66), and Group 5 (AOR 3.71; 95% CI 1.65-8.37) were associated with an increased risk of metachronous ACRN compared with Group 1.

CONCLUSIONS

Patients with small NAAs have an increased risk of metachronous ACRN. Postpolypectomy guidelines should consider including risk stratification between small and diminutive adenomas.

Metformin combined with endoscopic therapy in patients with familial polyposis associated with carcinoma: A case report

RATIONALE

Familial adenomatous polyposis (FAP) is an autosomal dominant genetic disease, with a very high cancer rate. At present, endoscopic resection of polyps ≥ 1 cm is often chosen for patients with non-cancerous polyps who are unwilling to undergo surgery, and regular review is conducted. Once the polyps are pathologically confirmed to be cancerous, surgical resection of the diseased large intestine is generally recommended, but surgery often leads to a series of complications. So what do you do with cancer patients who don't want surgery?

PATIENT CONCERNS

A 19-year-old woman presented with intermittent hematochezia with abdominal pain. A colonoscopy revealed hundreds of intestinal polyps.

DIAGNOSES

The patient had a family history of FAP, and there were hundreds of polyps in the intestine. The pathology was adenomatous, and some polyps became cancerous, which met the diagnostic criteria of FAP.

INTERVENTIONS

Endoscopic examination was arranged for the patient, the resection of intestinal polyps ≥ 1 cm was given priority, and other polyps were removed as far as possible. After that, metformin 500 mg orally was given twice a day, and endoscopic follow-up was conducted every 6 months. During each endoscopic follow-up, intestinal polyps ≥ 1 cm were preferred to be removed, and other polyps were removed as far as possible.

OUTCOMES

The patient's abdominal pain and blood in the stool disappeared after endoscopic treatment. Cancerous polyps were found at the second and third follow-up visits, but the patient always refused surgical treatment. After 4 years of follow-up, polyp load was significantly reduced, abdominal pain and bloody stool symptoms did not appear again, and imaging examination showed no tumor recurrence and metastasis.

LESSONS

Endoscopic polyp resection is an important method to treat the clinical symptoms of FAP. Metformin combined with endoscopic therapy is a good alternative for patients with familial polyposis who do not want surgery. When the polyp is cancerous and the polyp is radically resected by the endoscope, if the patient refuses additional surgery, oral metformin combined with endoscopic follow-up can be considered.

Colon Capsule Endoscopy in the Diagnosis of Colon Polyps: Who Needs a Colonoscopy?

Colon screening programs have reduced colon cancer mortality. Population screening should be minimally invasive, safe, acceptably sensitive, cost-effective, and scalable. The range of screening modalities include guaiac or immunochemical fecal occult blood testing and CT colonography and colonoscopy. A number of carefully controlled studies concur that second-generation capsule endoscopy has excellent sensitivity for polyp detection and a high negative predictive value. Colon capsules fulfill the screening expectation of safety, high sensitivity for polyp detection, and patient acceptance, and appear to straddle the divide between occult blood testing and colonoscopy. While meeting these criteria, there remains the challenges of scaling, capsule practitioner training, resource allocation, and implementing change of practice. Like CT colonography, capsule screening presents the clinician with a decision on the threshold for colonoscopy referral. Overall, colon capsules are an invaluable tool in polyp detection and colon screening and offer a filter that determines “who needs a colonoscopy?”.

Post-polypectomy surveillance: the present and the future

An appropriate post-polypectomy surveillance program requires the effectiveness of reducing colorectal cancer and safety. In addition, the post-polypectomy surveillance program should consider the burden of limited medical resource capacity, cost-effectiveness, and patient adherence. In this sense, a risk-stratified surveillance program based on baseline colonoscopy results is ideal. Major international guidelines for post-polypectomy surveillance, such as those from the European Union and the United States, have recommended risk-stratified surveillance programs. Both guidelines have recently been updated to better differentiate between high- and low-risk individuals. In both updated guidelines, more individuals have been downgraded to lower-risk groups that require less frequent or no surveillance. Furthermore, increased attention has been paid to the surveillance of patients who undergo serrated polyp removal. Previous guidelines in Japan did not clearly outline the risk stratification in post-polypectomy surveillance. However, the new colonoscopy screening and surveillance guidelines presented by the Japan Gastroenterological Endoscopy Society include a risk-stratified post-polypectomy surveillance program. Further discussion and analysis of unresolved issues in this field, such as the optimal follow-up after the first surveillance, the upper age limit for surveillance, and the ideal method for improving adherence to surveillance guidelines, are warranted.

Calibrating Natural History of Cancer Models in the Presence of Data Incompatibility: Problems and Solutions

The calibration of cancer natural history models is often challenged by a lack of representative calibration targets, forcing modellers to rely on potentially incompatible datasets. Using a microsimulation colorectal cancer model as an example, the purposes of this paper are to (1) highlight the reasons for uncertainty in calibration targets, (2) illustrate practical and generalisable approaches for dealing with incompatibility in calibration targets, and (3) discuss the importance of future research in the area of incorporating uncertainty in calibration. The low quality of data and differences in populations, outcome definitions, and healthcare systems may result in incompatibility between the model and the data. Acknowledging reasons for data incompatibility allows assessment of the risk of incompatibility before calibrating the model. Only a few approaches are available to address data incompatibility, for instance addressing biases in calibration targets and their adjustment, relaxing the goodness-of-fit metric, and validation of the calibration targets to the data not used in the calibration. However, these approaches lack explicit comparison and validation, and so more research is needed to describe the nature and causes of indirect uncertainty (i.e. uncertainty that cannot be expressed in absolute quantitative forms) and identify methods for managing this uncertainty in healthcare modelling.

Efficacy and safety of endoscopic resection techniques of large colorectal lesions: experience of a referral center in Italy

BACKGROUND

Endoscopic mucosal resection and submucosal dissection (ESD) are treatments of choice for superficial neoplastic colorectal lesions. Only a few studies have compared these techniques.

AIM

To compare the efficacy and safety of endoscopic piecemeal mucosal resection (EPMR), ESD and hybrid-endoscopic submucosal dissection (H-ESD) of large colorectal lesions in a Western endoscopic center.

METHODS

This is a retrospective analysis on a prospective medical database of consecutive colorectal superficial lesions larger than 20 mm, resected by EPMR, ESD or H-ESD collected from 2015 to 2019.

RESULTS

Two hundred twenty-nine colorectal lesions were included. All lesions were completely endoscopically resected, 65.9% by EPMR, 19.7% by ESD and 14.4% by H-ESD. Endoscopic control after the index procedure was available for 86.5% patients. Among these patients, 80% had a second follow-up colonoscopy. The overall recurrence rate was 13.2, 0 and 6.1% for EPMR, ESD and H-ESD respectively, with a significant difference between EPMR and ESD. All recurrences were endoscopically treated during follow-up procedures. Risk of complications was not significantly different between the three groups.

CONCLUSIONS

EPMR, ESD and H-ESD are effective and safe procedures. Recurrence rate in EPMR was higher but can be managed endoscopically with high success rates. EPMR is faster and technically simpler so should be considered a potential first-line therapy for colorectal superficial neoplastic lesions.

Safety and Efficacy of Cold Snare Polypectomy Without Submucosal Injection for Large Sessile Serrated Lesions: A Prospective Study

BACKGROUND & AIMS

Cold snare polypectomy (CSP) has become the standard resection method for small colorectal polyps (<10 mm). Sessile serrated lesions (SSL) have low prevalence of advanced histology irrespective of size, and thus could be amenable to CSP. In this study, we evaluated the safety and efficacy of CSP for SSLs ≥10 mm.

METHODS

Between November 2018 and January 2020, we prospectively enrolled 300 consecutive patients who underwent CSP for 474 SSLs ≥10 mm. To delineate SSL borders, indigo carmine chromoendoscopy and/or image-enhanced endoscopy was conducted. Piecemeal CSP (pCSP) was performed in cases where en-bloc resection was difficult. Biopsy specimens were obtained from the margins of the post-polypectomy defect to confirm complete resection. Surveillance colonoscopy was performed to screen for local recurrence.

RESULTS

All lesions were successfully resected using CSP without submucosal injection. The median diameter of the resected lesions was 14 mm, and pCSP was used to resect 106 (22%) lesions. Post-polypectomy biopsies revealed residual serrated tissue in only one case (0.2%). Adverse events included immediate bleeding in 8 (3%) patients; no delayed bleeding events occurred, irrespective of the use of antithrombotic drugs. During a 7-month median follow-up period, surveillance colonoscopies were performed for 384 lesions (81%), and no local recurrences were detected.

CONCLUSIONS

CSP without submucosal injection is a safe and effective treatment for SSLs ≥10 mm. UMIN Clinical Trials, Number: UMIN000034763.

Recommendations for follow-up interval after colonoscopy with inadequate bowel preparation in a national colonoscopy quality registry

BACKGROUND AND AIMS

Endoscopist recommendations regarding a repeat colonoscopy after inadequate bowel cleanliness have not been fully described. Our aim was to evaluate the timing of recommendations for repeat colonoscopy after inadequate bowel preparation using a large, national colonoscopy registry.

METHODS

We performed a cross-sectional analysis of all outpatient screening and surveillance colonoscopies among adults ages 50 to 75 reported in the GI Quality Improvement Consortium from 2011 to 2018. The primary outcome was a recommendation to repeat colonoscopy within 1 year. Secondary outcomes were recommendations based on indication of colonoscopy and colonoscopy findings and predictors of a recommendation to follow-up within 1 year.

RESULTS

There were 260,314 colonoscopies with inadequate bowel preparation performed at 672 different sites by 4001 endoscopists. Of these, 31.9% contained a recommendation for follow-up within 1 year. This did not differ meaningfully by examination indication. The severity of colonoscopy findings influenced the recommendations for follow-up (within 1 year in 84.0% of cases with adenocarcinoma, 51.8% with any advanced lesion, and 23.2% with 1-2 small adenomas). Younger age, more severe pathology, location in the Northeast, and performance by an endoscopist with an adenoma detection rate ≥25% were associated with recommendations for follow-up within 1 year.

CONCLUSIONS

Only some colonoscopies with inadequate bowel preparation are recommended to be repeated within 1 year, which may have implications for potential missed lesions. Further understanding of reasons driving recommendations is an important next step to improving guideline-concordant colonoscopy practice.

Measuring and Improving Quality of Colonoscopy for Colorectal Cancer Screening

Colorectal cancer (CRC) is largely preventable, yet it remains a major public health issue as it is the third most common and deadly malignancy in the United States. While there are many ways to screen for CRC, colonoscopy remains the gold standard as it is the only test that is both cancer-detecting and cancer-preventing through removal of precancerous polyps. Through identifying and removing neoplastic lesions, colonoscopy reduces CRC incidence by 31%-91% and CRC mortality by 65%-88%. However, colonoscopy is not an infallible test-there is a chance for missed lesions during the exam and there is substantial variation in outcomes among endoscopists. To enhance the quality of colonoscopic exams, and ultimately to improve CRC outcomes, quality indicators have been developed for measuring endoscopists' performance. In this review, we describe the colonoscopic quality indicators and benchmarks recommended by the American Society for Gastrointestinal Endoscopy/American College of Gastroenterology Task Force on Quality in Endoscopy for screening colonoscopies in average-risk individuals. Measuring and monitoring endoscopists' performance on these measures are critical first steps in striving toward conducting high quality exams. We also review the evidence for interventions that aim to improve critical measures including adenoma detection rate, withdrawal time, cecal intubation, and bowel preparation quality. Finally, we provide a preview of the forthcoming Advancing Care for Appropriate Colon Health Merit-Based Incentive Payment System Value Pathway by the Centers for Medicare & Medicaid Services and its potential impact on clinical practice.

Designing a Predictive Model for Colorectal Neoplasia Diagnosis Based on Clinical and Laboratory Findings in Colonoscopy Candidate Patients

BACKGROUND

Health authorities have expanded two strategies to diminish CRC-related influence: CR screening and improve diagnostic process in symptomatic patients. The aim of the current study is to design a predictive model to identify the most important risk factors that can efficiently predict patients who have high risk of colorectal neoplasia.

METHOD

A cross-sectional study was constructed to include all patients who had positive test for FIT or had one or more risk factors for colorectal cancer based on the guidelines of detecting high-risk groups for colorectal cancer in Iran. Multivariable binary logistic regression model was constructed for prediction of colorectal neoplasia. We used sensitivity, specificity, positive and negative predictive value, and positive and negative likelihood ratio to check the accuracy. The Hosmer-Lemeshow test, chi-square test, and p value were used to determine the precision of model.

RESULT

Following an AIC stepwise selection model, only nine potential variables, namely gender, watery diarrhea, IBD, abdominal pain, melena, body mass index, depression drug, anti-inflammatory drug, and age, were found to be a predictor of colorectal neoplasia. The best cut-point probability in the final model was 0.27 and results of sensitivity and specificity, based on maximizing these two criteria, were 66% and 62%, respectively.

CONCLUSION

Overall, our model prediction was comparable with other risk prediction models for colorectal cancer. It had a modest discriminatory power to distinguish an individual's neoplasia colorectal risk.

Establishment and Verification of Scoring System for Colorectal Adenoma Recurrence

Objective

The purpose of this study was to establish and verify a risk-scoring system for colorectal adenoma recurrence.

Methods

A total of 359 patients with colorectal adenoma who underwent polypectomy from October 2017 to December 2018 were included in this retrospective study. Information including taking traditional Chinese medicine, demographic characteristics, adenoma characteristics were collected. The patients will review the colonoscopy one year after surgery. The patients were divided into a modeling cohort (216 cases) and a model validation cohort (143 cases) according to the ratio of 6:4. Modeling and model verification were performed by logistic regression, ROC curve, nomogram (calibration chart) and other methods.

Results

After adjusting for confounding factors by logistic regression, it was found that taking Chinese medicine, the number, size, site, pathological type and morphology of adenoma were independent influencing factors for the recurrence of colorectal adenoma. The area under the ROC curve (AUC) in the model validation cohort of established risk scoring system was 0.771 (95% CI: 0.694–0.847), indicating that there was good consistency.

Conclusion

The established risk prediction model of colorectal adenoma recurrence and its risk scoring system performed well and had high predictive value.

Long-term cumulative incidence of metachronous advanced colorectal neoplasia after colonoscopy and a novel risk factor: a cohort study

BACKGROUND AND AIM

Long-term cumulative incidence of and risk factors for metachronous advanced colorectal neoplasia, including both advanced colorectal adenoma (≥10 mm, or with villous or high-grade dysplasia) and colorectal cancer, are critical for surveillance strategies. The aim of this study was to determine the cumulative incidence of metachronous advanced colorectal neoplasia and its risk factors.

METHODS

A retrospective cohort study was conducted on 6720 consecutive individuals who underwent general health check-ups and colonoscopy. Colorectal adenomas at initial colonoscopy were categorized as low-risk (1-2 small [<10 mm] tubular adenomas) or high-risk adenoma (≥3 tubular adenomas of any size; at least one adenoma ≥10 mm; or villous adenoma or adenoma with high-grade dysplasia). Kaplan-Meier estimates and hazard ratio by Cox-proportional hazard regression were calculated.

RESULTS

The cumulative incidence (95% confidence interval [CI]) of metachronous advanced colorectal neoplasia at 5 and 10 years was 5.7% [4.6-7.1], and 11% [8.9-14] in the low-risk adenoma group, and 10% [8.6-13], and 17% [14-21] in high-risk adenoma group, respectively. Adjusted hazard ratio [95% CI] of low-risk adenoma (vs. no colorectal adenoma), high-risk adenoma (vs. no colorectal adenoma), current smoking and positive fecal immunochemical test were 1.34 [1.04-1.74], 1.94 [1.48-2.55], 1.55 [1.2-2.02] and 1.69 [1.35-2.1], respectively. Adjusted hazard ratio [95% CI] of positive fecal immunochemical test was 1.88 [1.29-2.74] in those with normal colonoscopy.

CONCLUSIONS

Both low-risk and high-risk adenomas confer substantial risk for metachronous advanced colorectal neoplasia at 10 years. Positive fecal immunochemical test was a significant risk factor for metachronous advanced colorectal neoplasia despite normal colonoscopy.

The necessity of intensive surveillance colonoscopy for patients with a remaining right colon after resection of colorectal cancer: a retrospective cohort study

PURPOSE

To clarify how often postoperative surveillance colonoscopy should be undertaken based on the risk factors for the development of metachronous cancer (MC) and advanced adenoma (AA) after surgery for colorectal cancer.

METHODS

We collected data of consecutive patients who underwent curative resection for primary colorectal cancer between 2005 and 2012, with preoperative colonoscopy and surveillance colonoscopy at 1 year after surgery (406 patients, mean age: 69 years, 59% male). The detection rates of AA (with villous features, > 10 mm or high-grade dysplasia) and MC by surveillance colonoscopy were the primary outcomes.

RESULTS

At 5 years, colonoscopy was performed as postoperative surveillance an average of 3.2 times. AA and MC were detected in 57 (14.0%) and 18 patients (4.4%), respectively. Both lesions were more common in the right colon (n = 43) than in the left colon (n = 28). The detection rate did not differ to a statistically significant extent according to the number of colonoscopies performed for surveillance (p = 0.21). However, after left-sided colectomy, both types of lesions were more commonly detected in those who received ≥ 3 colonoscopies than in those with one or two colonoscopies (p = 0.04).

CONCLUSION

A remaining right colon after left-sided colectomy was associated with a higher risk of developing AA and MC. Physicians should consider performing surveillance colonoscopy more frequently if the right colon remains after surgery.

Risk of colorectal cancer in patients with positive results of fecal immunochemical test performed within 5 years since the last colonoscopy

BACKGROUND/AIMS

Annual fecal immunochemical tests (FITs) are often repeated within the recommended colonoscopy surveillance intervals. However, it remains unclear whether interval FITs are useful. To answer this question, we assessed the risk of colorectal cancer (CRC) according to the interval from the last colonoscopy to an FIT.

METHODS

Using the Korean National Cancer Screening Program database, we collected data on patients who underwent FITs in 2011. Patients with positive FIT results were classified into three groups according to their previous colonoscopy interval: 0.5 to 5 years (group 1), 5 to 10 years (group 2), and ≥ 10 years or no colonoscopy (group 3). CRC incidence was defined as CRC diagnosed within 1 year after an FIT.

RESULTS

Among 177,660 patients with positive FIT results, the incidence of CRC in groups 1, 2, and 3 was 0.72% (n = 214/29,575), 1.28% (n = 116/9,083), and 3.88% (n = 5,387/139,002), respectively. The age- and sex-adjusted risk for CRC was higher in groups 2 (odds ratio [OR], 1.79; 95% confidence interval [CI], 1.43 to 2.25) and 3 (OR, 5.56; 95% CI, 4.85 to 6.38) than in group 1. Among patients who did and did not undergo a polypectomy during the previous colonoscopy, those in group 2 had a higher rate of CRC than those in group 1 (without polypectomy: 1.15% vs. 0.63%; OR, 1.79; 95% CI, 1.37 to 2.34) (with polypectomy: 2.37% vs. 0.93 %; OR, 2.30; 95% CI, 1.44 to 3.69).

CONCLUSION

In patients with positive FIT results who had undergone a colonoscopy within the past 5 years, the risk of CRC is very low, regardless of whether a polypectomy was performed, suggesting that interval FITs are not useful.

Associations of Novel Lifestyle- and Whole Foods-Based Inflammation Scores with Incident Colorectal Cancer Among Women

BACKGROUND

Chronic inflammation, associated with lifestyle and dietary factors, may contribute to colorectal carcinogenesis. To address this, we investigated associations of previously validated, inflammation biomarker panel-weighted, novel, 4-component lifestyle (LIS) and 19-component predominately whole foods-based dietary (DIS) inflammation scores with incident colorectal cancer (CRC) in the prospective Iowa Women's Health Study (IWHS; 1986-2012; n = 34,254, of whom 1,632 developed CRC).

METHODS

We applied the published scores' components' weights, summed the weighted components to constitute the scores (higher scores reflect a higher balance of pro-inflammatory exposures), and investigated LIS- and DIS-CRC associations using multivariable Cox proportional hazards regression.

RESULTS

The multivariable-adjusted hazards ratios (HR) and their 95% confidence intervals (CI) for CRC among participants in the highest relative to the lowest LIS and DIS quintiles were 1.47 (1.26, 1.72; Ptrend < 0.01) and 1.07 (0.91, 1.25; Ptrend = 0.22), respectively. The corresponding findings for distal colon cancers were HR 1.78 (1.29, 2.47) and HR 1.34 (0.98, 1.84), respectively. Among those in the highest relative to the lowest joint LIS/DIS quintile, the HR for CRC was 1.60 (95% CI 1.30, 1.98).

CONCLUSIONS

Our results suggest that a more pro-inflammatory lifestyle, alone and jointly with a more pro-inflammatory diet, may be associated with higher CRC risk.

Role of Bowel Preparation in Adenoma Detection Rate and Follow-up Recommendations in African American Dominant Patient Population

Introduction: Bowel preparation quality in colonoscopy is one of the most essential components of quality assessment. According to the latest guidelines, inadequate bowel preparation warrants repeat colonoscopy in less than a year. Our aim was to investigate the role of bowel preparation in adenoma detection rate (ADR), its relationship with patients' demographics, and compliance with subsequent surveillance recommendations with guidelines.

Methods: This is a retrospective chart review study. Bowel preparation quality was divided into three categories: high, intermediate, and low. ADR and polyp detection rates (PDR) were calculated as the number of patients with adenoma or polyp divided by the total number of patients.

Results: Among 1,062 patients (934 African American and 128 non-African American) 81%, 11%, and 8% had high, intermediate, and low-quality bowel preparations, respectively. Race, gender, age, type of endoscopist, and body mass index did not play any role in bowel preparation quality. ADR and PDR were significantly higher in African Americans as compared to non-African Americans. ADR was significantly lower in the low-quality as compared to the high- and intermediate-quality bowel preparations (OR=2.13; p=0.0032). Bowel preparation quality was not correlated with subsequent follow-up recommendations. Academic gastroenterologists and surgeons had the highest and lowest compliance with surveillance guidelines, respectively.

Conclusions: Racial and gender disparity appears to have no meaningful effect on the quality of bowel preparation. Only two categories (adequate [high/intermediate] or inadequate [low-quality]) may be used for follow-up recommendations. Non-compliance with surveillance guidelines is concerning and may inadvertently increase the interval risk of colorectal cancer.

Risk of Colorectal Cancer and Cancer Related Mortality After Detection of Low-risk or High-risk Adenomas, Compared With No Adenoma, at Index Colonoscopy: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

The risk of metachronous colorectal cancer (CRC) among patients with no adenomas, low-risk adenomas (LRAs), or high-risk adenomas (HRAs), detected at index colonoscopy, is unclear. We performed a systematic review and meta-analysis to compare incidence rates of metachronous CRC and CRC-related mortality after a baseline colonoscopy for each group.

METHODS

We searched the PubMed, Embase, Google Scholar, and Cochrane databases for studies that reported the incidence of CRC and adenoma characteristics after colonoscopy. The primary outcome was odds of metachronous CRC and CRC-related mortality per 10,000 person-years of follow-up after baseline colonoscopy for all the groups.

RESULTS

Our final analysis included 12 studies with 510,019 patients (mean age, 59.2 ± 2.6 years; 55% male; mean duration of follow up, 8.5 ± 3.3 years). The incidence of CRC per 10,000 person-years was marginally higher for patients with LRAs compared to those with no adenomas (4.5 vs 3.4; odds ratio [OR], 1.26; 95% CI, 1.06-1.51; I²=0), but significantly higher for patients with HRAs compared to those with no adenoma ( 13.8 vs 3.4; odds ratio [OR], 2.92; 95% CI, 2.31-3.69; I²=0 ) and patients with HRAs compared to LRAs (13.81 vs 4.5; OR, 2.35; 95% CI, 1.72-3.20; I²=55%). However, the CRC-related mortality per 10,000 person-years did not differ significantly for patients with LRAs compared to no adenomas (OR, 1.15; 95% CI, 0.76-1.74; I²=0) but was significantly higher in persons with HRAs compared with LRAs (OR, 2.48; 95% CI, 1.30-4.75; I²=38%) and no adenomas (OR, 2.69; 95% CI, 1.87-3.87; I²=0).

CONCLUSIONS

The results of this systematic review and meta-analysis demonstrate that the risk of metachronous CRC and mortality is significantly higher for patients with HRAs, but this risk is very low in patients with LRAs, comparable to patients with no adenomas. Follow-up of patients with LRAs detected at index colonoscopy should be the same as for persons with no adenomas.

Increased Sessile Serrated Adenoma Detection Rate With Mechanical New Technology Devices: A Systematic Review and Meta-Analysis

GOAL

This meta-analysis aims to compare the sessile-serrated adenoma detection rate (SSADR) of currently available mechanical new technology devices (NTDs) to conventional colonoscopy (CC).

BACKGROUND

NTDs including Endocuff, EndoRing, G-Eye, and AmplifEYE were developed with the aim of improving adenoma detection rate by enhancing colonic mucosal visualization. Increasing awareness of the risk of sessile-serrated adenoma progression to malignancy has ushered a need to increase the detection of these characteristically flat lesions.

STUDY

Embase and PubMed/Medline databases were searched from inception through January 2019 for published manuscripts or major conference abstracts reporting SSADR with Endocuff, EndoRing, G-Eye, AmplifEYE, and CC. Randomized controlled trials, high-quality case-control, cohort, and observational studies in adults with >10 subjects were included. The primary outcome was pooled SSADR odds ratio (ORs) with 95% confidence interval (95% CI) comparing CC with the NTDs. In addition, an analysis comparing each device to CC was performed.

RESULTS

Of 207 citations identified, a total of 14 studies with 12,655 subjects were included in our analysis (5931 subjects with NTDs and 6724 with CC). There were 12 studies with Endocuff, 2 with EndoRing, 1 with G-EYE, and 1 with AmplifEYE. The mean age was 62.4 years and 57.5% were males. Pooled SSADR with NTDs was 12.3% as compared with 6.4% with CC, with an OR of 1.81 (95% CI: 1.6-2.0, I2: 77%). Analysis of Endocuff alone yielded an OR 1.81 (95% CI: 1.6-2.1, I2: 79%).

CONCLUSION

Mechanical NTDs, notably Endocuff, are a safe and effective tool to increase the SSADR.

Metachronous neoplasms in patients with laterally spreading tumours during surveillance

Background

Laterally spreading tumours represent a major challenge for endoscopic detection and resection.

Objective

To examine synchronous and metachronous neoplasms in patients with laterally spreading tumours.

Methods

We prospectively collected colonoscopy and histopathology data from patients who underwent colonoscopy in our centre at up to 6 years' follow‐up. Post‐resection surveillance outcomes between laterally spreading tumours, flat colorectal neoplasms 10 mm or greater, and large polypoid colorectal neoplasms, polypoid colorectal neoplasms 10 mm or greater, were compared.

Results

Between 2008 and 2012, 8120 patients underwent colonoscopy for symptoms (84.6%), screening (6.7%) or surveillance (8.7%). At baseline, 151 patients had adenomatous laterally spreading tumours and 566 patients had adenomatous large polypoid colorectal neoplasms. Laterally spreading tumour patients had more synchronous colorectal neoplasms than large polypoid colorectal neoplasm patients (mean 3.34 vs. 2.34, p < 0.001). Laterally spreading tumour patients significantly more often developed metachronous colorectal neoplasms (71.6% vs. 54.2%, p = 0.0498) and colorectal neoplasms with high grade dysplasia/submucosal invasion than large polypoid colorectal neoplasm patients (36.4% vs. 15.8%, p < 0.001). After correction for age and gender, laterally spreading tumour patients were more likely than large polypoid colorectal neoplasm patients to develop a colorectal neoplasm with high grade dysplasia or submucosal invasion (hazard ratio 2.9, 95% confidence interval 1.8–4.6). The risk of metachronous colorectal cancer was not significantly different in laterally spreading tumours compared to large polypoid colorectal neoplasm patients.

Conclusion

Patients with laterally spreading tumours developed more metachronous colorectal neoplasms with high grade dysplasia/submucosal invasion than large polypoid colorectal neoplasm patients. Based on these findings endoscopic treatment and surveillance recommendations for patients with laterally spreading tumours should be optimised.

Summarize the established knowledge on this subject

Laterally spreading tumours (LSTs) are a heterogeneous group of large, predominantly benign flat neoplasms that can be endoscopically treated, requiring additional time and expertise

LSTs consist of different endoscopic subtypes which are predictive of the risk of submucosal invasion (SMI)

Patients with LSTs harbour more synchronous neoplasms than patients with large polypoid colorectal neoplasms (LP‐CRNs)

What are the significant and/or new findings of this study?

Patients with LSTs more frequently have metachronous neoplasms than patients with LP‐CRNs, justifying strict surveillance

LSTs can be effectively managed by conventional endoscopic resections in most cases

Optimal surveillance interval after piecemeal endoscopic mucosal resection for large colorectal neoplasia: a multicenter randomized controlled trial

BACKGROUND AND AIMS

Colorectal neoplastic lesions (≥ 20 mm) are commonly treated via piecemeal endoscopic mucosal resection (p-EMR) but have a high rate of local recurrence. We aimed to clarify the optimal surveillance interval after p-EMR for these neoplasias.

METHODS

In this multicenter (15 participating institutions) prospective, randomized trial, 180 patients recruited over a 4-year period and were classified based on tumor location, tumor diameter, histological diagnosis, institution, and number of resected specimens. The patients underwent curative p-EMR followed by scheduled surveillance colonoscopy at 3, 6, 12, and 24 months after p-EMR (group A; n = 90) or at 6, 12, and 24 months after p-EMR (group B; n = 90). The primary endpoint was cumulative local recurrence at 6 months after p-EMR. Secondary endpoints included local recurrence and the cumulative surgical resection rate of recurrent tumors during the 24-month follow-up period.

RESULTS

The median tumor diameter was 25 mm (IQR 20-30). Six months after p-EMR, 12 and 6 local recurrences were noted in groups A and B, which corresponded to 13 and 8 recurrences, respectively, during the 24-month surveillance period. The primary and secondary endpoints of recurrence were not significantly different between the groups on either intention-to-treat or per-protocol analysis; no surgery case was observed in group B when a strict surveillance protocol of 6-, 12-, and 24-month follow-up post-EMR was followed.

CONCLUSIONS

For patients who underwent p-EMR for neoplastic lesions, additional postprocedural 3-month surveillance did not show superior results in detecting recurrence compared with a 6-month surveillance interval.

CLINICAL TRIAL REGISTRATION

UMIN000015740.

Relationship between the polyp detection rate and the post-colonoscopy colorectal cancer rate

AIM

the adenoma detection rate is the quality indicator of colonoscopy that is most closely related to the development of interval colorectal cancer or post-colonoscopy colorectal cancer. However, the recording of this indicator in different units of gastrointestinal endoscopy is obstructed due to the large consumption of resources required for its calculation. Several alternatives have been proposed, such as the polyp detection rate. The objective of this study was to evaluate the relationship between the polyp detection rate and its influence on post-colonoscopy colorectal cancer rate.

PATIENTS AND METHODS

in this study, 12,482 colonoscopies conducted by 14 endoscopists were analyzed. The polyp detection rate was calculated for each endoscopist. Endoscopists were grouped into quartiles (Q1, Q2, Q3, and Q4), from lowest to highest polyp detection rate, in order to evaluate whether there were any differences in the development of post-colonoscopy colorectal cancer.

RESULTS

the lowest polyp detection rate was 20.66% and the highest was 52.16%, with a median of 32.78 and a standard deviation of ± 8.54. A strong and positive association between polyp endoscopy diagnosis and adenoma histopathology result was observed and a linear regression was performed. A significantly higher post-colonoscopy colorectal cancer rate was observed in the group of endoscopists with a lower polyp detection rate (p < 0.02).

CONCLUSION

polyp detection rate is a valuable quality indicator of colonoscopy and its calculation is much simpler than that of the adenoma detection rate. In our study, the prevalence of post-colonoscopy colorectal cancer was inversely and significantly related to the endoscopists' polyp detection rate.

Management of malignant colonic polyps

With the implementation of colorectal cancer screening programs, there has been an increasing incidence of malignant colonic polyps (MP). The attending surgeon is often faced with the management dilemma of whether polypectomy can be considered adequate treatment or if formal oncological resection is required. While endoscopic therapy avoids the risks and morbidity of surgery, there is a potential trade-off of under-staging and inadequate treatment. Surgery, on the other hand confers the benefits of clear resection margins, nodal staging and the ability to prognosticate and guide the decision for adjuvant therapy. This article sets out to review the histopathologic prognostic factors of MP and the various management and surveillance strategies.

Increased Risk of Colorectal Cancer Tied to Advanced Colorectal Polyps: An Untapped Opportunity to Screen First-Degree Relatives and Decrease Cancer Burden

Advanced adenomas represent a subset of colorectal polyps that are known to confer an increased risk of colorectal neoplasia to the affected individual and their first-degree relatives (FDRs). Accordingly, professional guidelines suggest earlier and more intensive screening for FDRs of those with advanced adenomas similar to FDRs of those with colorectal cancer (CRC). Although the risk to family members is less clear among patients with advanced serrated polyps, they are often considered in the same category. Unfortunately, there is a growing concern that patients, endoscopists, and primary care providers are unaware of the familial risk associated with these polyps, leaving a wide gap in screening these high-risk individuals. Herein, we propose a standardized language around advanced colorectal polyps and present a detailed review of the literature on associated familial risk. We outline the challenges to implementing the current screening recommendations and suggest approaches to overcome these limitations, including a proposed new colonoscopy quality metric to capture communication of familial CRC risk. Improving screening in these high-risk groups has the potential to substantially reduce the burden of CRC.

Association Between Age and Complications After Outpatient Colonoscopy

Importance

There are insufficient data describing the incidence and risk factors of postcolonoscopy complications in older individuals.

Objective

To assess the association between older age (≥75 years) and the risk of postcolonoscopy complications.

Design, Setting, and Participants

This population-based retrospective cohort study included adults (≥50 years) undergoing outpatient colonoscopy between April 2008 and September 2017, identified from Ontario administrative databases. Individuals with inflammatory bowel disease and hereditary colorectal cancer syndromes were excluded. The study population was subdivided into a colorectal cancer screening-eligible cohort (patients aged 50-74 years) and an older cohort (patients aged ≥75 years). The statistical analysis was conducted from December 2018 to September 2019.

Exposures

Older age (≥75 years).

Main Outcomes and Measures

The primary outcome was postcolonoscopy complications, defined as the composite of hospitalization or emergency department visits in the 30-day period after the outpatient colonoscopy. Secondary outcomes included incidence of surgically treated colorectal cancer and all-cause mortality at 30 days. Independent variables associated with postcolonoscopy complications were also assessed.

Results

The study sample included 38 069 patients; the mean (SD) age was 65.2 (10.1) years, there were 19 037 women (50.0%), and 27 831 patients (73.1%) underwent a first colonoscopy. The cumulative incidence of complications was 3.4% (1310 patients) in the overall population, and it was higher in individuals aged 75 years or older (515 of 7627 patients [6.8%]) than in screening-eligible cohort (795 of 30 443 patients [2.6%]) (P < .001). Independent risk factors for postcolonoscopy complications were age 75 years or older (odds ratio [OR], 2.3; 95% CI, 2.0-2.6), anemia (OR, 1.4; 95% CI, 1.2-1.7), cardiac arrhythmia (OR, 1.7; 95% CI, 1.2-2.2), congestive heart failure (OR, 3.4; 95% CI, 2.5-4.6), hypertension (OR, 1.2; 95% CI, 1.0-1.5), chronic kidney disease (OR, 1.8; 95% CI, 1.1-3.0), liver disease (OR, 4.7; 95% CI, 3.5-6.5), smoking history (OR, 3.2; 95% CI, 2.4-4.3), and obesity (OR, 2.3; 95% CI, 1.2-4.2). The number of previous colonoscopies was associated with a lower risk of complications (OR, 0.9; 95% CI, 0.7-1.0). The incidence of surgically treated colorectal cancer was higher in the older cohort than the screening-eligible cohort (119 patients [1.6%] vs 144 patients [0.5%]; P < .001). All-cause mortality rates were 0.1% overall (39 patients) and 0.1% (19 patients) for individuals aged 50 to 74 years and 0.2% (20 patients) for those aged 75 years and older (P < .001).

Conclusions and Relevance

In this population-based cohort study of individuals living in southern Ontario, age of 75 years and older was associated with a higher risk of 30-day postprocedure complications after outpatient colonoscopy. These findings suggest that the decision to perform a colonoscopy should be carefully considered in patients older than 75 years, especially in the presence of comorbidities. Further studies are needed to better understand the benefits of invasive procedures as opposed to less invasive approaches for colorectal cancer screening and surveillance among older patients.

Challenges and Approaches to Measuring Repeat Fecal Immunochemical Test for Colorectal Cancer Screening

BACKGROUND

Colorectal cancer screening with fecal immunochemical testing (FIT) can reduce colorectal cancer-related mortality. Effectiveness of FIT may be compromised when patients do not adhere to a regular schedule. However, having no standard measure of repeat FIT presents challenges for assessing effectiveness across populations and settings. We compared three measures of repeat FIT in a large, integrated health care system in Dallas, Texas.

METHODS

We identified 18,257 patients age-eligible (50-60 years) for FIT in January 1-December 31, 2010 and followed over four rounds of screening. Measures included: (i) repeat FIT in prior screeners, or completion of FIT within 9-15 months of the previous; (ii) yes-no patterns, whereby patients were assigned yes or no in 9-15 month windows; and 3) proportion of time covered (PTC), or the amount of time patients were up-to-date with screening relative to time eligible.

RESULTS

Repeat FIT varied by measure. Using a prior screeners measure, 15.8% of patients with a normal FIT in round 1 completed repeat FIT in round 2. Repeat FIT was notably higher (52.3%) using PTC. The most common yes-no pattern was YNNN or "one-and-done," and only 9.4% of patients completed two consecutive FITs across all rounds (YYNN).

CONCLUSIONS

Different measures of repeat FIT yielded a range of estimates, making comparison across studies difficult. Researchers should weigh the advantages and disadvantages of each measure and select the most appropriate to their research question.

IMPACT

Our study highlights the need for future research of repeat FIT measures that best approximate screening effectiveness.

Water Exchange (WE) and Quality Improvement-Enhanced Advanced Adenoma Detection: A Pooled Data Analysis of 6 Randomized Controlled Trials

INTRODUCTION

Advanced adenomas (≥10 mm in diameter, >25% villous, or high-grade dysplasia), a marker of colorectal cancer risk, are used to stratify patients for closer surveillance. Modern accessories, endoscopes, and age-adjusted evaluation have variable impacts on the advanced adenoma detection rate (AADR). In 1 randomized controlled trial (RCT) comparing air insufflation (AI) with water exchange (WE), the right colon AADR was significantly increased by WE. Four network meta-analyses reported that WE significantly increased overall adenoma detection rate (ADR), but the impact on AADR was not addressed.

AIM

The aim of this study was to test the hypothesis that WE significantly increased AADR compared with AI.

METHOD

Six Clinicaltrial.gov-registered RCTs were reported by a group of WE investigators. Data including AADR (primary outcome) and overall ADR (secondary outcome) were pooled.

RESULTS

A total of 5407 patients were randomized to AI (2699) and WE (2708). Compared with AI, WE significantly increased AADR (5.7% vs. 8.3%, P=0.001) and overall ADR (20.9% vs. 27.4%, P=0.001).

CONCLUSIONS

In contrast to published reports, which showed variable impacts on AADR, WE was consistent in increasing AADR in 6 reported RCTs. The pooled data confirm that the impact of WE in increasing AADR was significant. The significantly enhanced overall ADR indicated that WE provided a higher quality outcome than AI. The significant improvement in AADR confirmed WE to be clinically relevant and has finally arrived as a timely addition to colorectal cancer prevention programs.

Long-term risk of colorectal cancer after screen-detected adenoma: Experiences from a Danish gFOBT-positive screening cohort

Fecal occult blood test (FOBT) screening for colorectal cancer (CRC) is implemented in several countries. Approximately half of all FOBT-positive persons have screen-detected adenomas. Despite removal of these, patients with large/multiple adenomas have increased risk of later developing new advanced adenomas and CRC. International guidelines exist for colonoscopic surveillance following adenoma removal. These divide patients into low-, intermediate- and high-risk groups. We followed 711 FOBT-positive patients with screening adenoma identified during population-based CRC screening in two Danish counties in 2005-2006. As reference population, we included 1,240,348 persons in the same age group from the rest of Denmark not included in the screening. We estimated the long-term CRC risk stratified by adenoma findings during screening and compared to the reference group. After 12 years follow-up, the CRC incidence among all adenoma patients was 322 cases per 100,000 person-years (95% confidence interval [CI]: 212-489) ranging from 251 (95% CI: 94-671) to 542 (95% CI: 300-978) cases per 100,000 person-years in the low- and high-risk groups, respectively. In the reference population, the CRC incidence was 244 (95% CI: 242-247) per 100,000. Patients with screen-detected high-risk adenomas after a positive FOBT had an almost doubled risk of CRC compared to the reference population (adjusted hazard ratio [aHR] 1.95, 95% CI: 1.08-3.51), and the incidence in those with no follow-up visits was over 3.6 (aHR 3.64, 95% CI: 1.82-7.29) times the incidence in the reference population. The increased CRC risk could be controlled if high-risk patients underwent follow-up colonoscopy (aHR 0.87, 95% CI: 0.28-2.69).

"Obscure" Appendiceal Orifice Polyps Can Be Challenging to Identify by Colonoscopy

The primary purpose of screening colonoscopy is the detection and subsequent removal of precancerous polyps. However, effective recognition of appendiceal lesions with a standard endoscope is often challenging and is limited to the base of the cecum and appendiceal orifice. The majority of appendiceal polyps are found incidentally following an appendectomy, though rarely they may be discovered during a colonoscopy. Despite being visualized by colonoscopy, most of these polyps are generally referred for surgical resection. The risk of developing carcinoma in patients with appendiceal polyps is likely similar to that of other colonic polyps, so it is essential for the endoscopist to examine and visualize the appendiceal orifice thoroughly. Various techniques are available to the endoscopist that can increase the accuracy of colonoscopic evaluation. These include luminal inflation and deflation, looking behind and pressing haustral folds, and repetitive passage of the scope over poorly visualized areas. To our knowledge, only 3 cases have been reported in the literature describing the discovery of obscure appendiceal polyps using colonoscopic techniques. Here we describe three cases of appendiceal orifice polyps missed on initial visualization but subsequently protruded into the cecum following prolonged examination and gentle deflation in the cecum. The endoscopist should consider the possibility of an appendiceal neoplasm, especially if other colonic polyps have been found. Endoscopists should spend adequate time examining the cecum during a screening colonoscopy to expose and thoroughly examine the appendiceal region.

Berberine versus placebo for the prevention of recurrence of colorectal adenoma: a multicentre, double-blinded, randomised controlled study

BACKGROUND

Chemoprevention of colorectal adenoma and colorectal cancer remains an important public health goal. The present study aimed to investigate the clinical potential and safety of berberine for prevention of colorectal adenoma recurrence.

METHODS

This double-blind, randomised, placebo-controlled trial was done in seven hospital centres across six provinces in China. Individuals aged 18-75 years who had at least one but no more than six histologically confirmed colorectal adenomas that had undergone complete polypectomy within the 6 months before recruitment were recruited and randomly assigned (1:1) to receive berberine (0·3 g twice daily) or placebo tablets via block randomisation (block size of six). Participants were to undergo a first follow-up colonoscopy 1 year after enrolment, and if no colorectal adenomas were detected, a second follow-up colonoscopy at 2 years was planned. The study continued until the last enrolled participant reached the 2-year follow-up point. All participants, investigators, endoscopists, and pathologists were blinded to treatment assignment. The primary efficacy endpoint was the recurrence of adenomas at any follow-up colonoscopy. Analysis was based on modified intention-to-treat, with the full analysis set including all randomised participants who received at least one dose of study medication and who had available efficacy data. The study is registered with ClinicalTrials.gov, number NCT02226185; the trial has ended and this report represents the final analysis.

FINDINGS

Between Nov 14, 2014, and Dec 30, 2016, 553 participants were randomly assigned to the berberine group and 555 to the placebo group. The full analysis set consisted of 429 participants in the berberine group and 462 in the placebo group. 155 (36%) participants in the berberine group and 216 (47%) in the placebo group were found to have recurrent adenoma during follow-up (unadjusted relative risk ratio for recurrence 0·77, 95% CI 0·66-0·91; p=0·001). No colorectal cancers were detected during follow-up. The most common adverse event was constipation (six [1%] of 446 patients in the berberine group vs one [<0·5%] of 478 in the placebo group). No serious adverse events were reported.

INTERPRETATION

Berberine 0·3 g twice daily was safe and effective in reducing the risk of recurrence of colorectal adenoma and could be an option for chemoprevention after polypectomy.

FUNDING

National Natural Science Foundation of China.

Computer-assisted assessment of colonic polyp histopathology using probe-based confocal laser endomicroscopy

INTRODUCTION

Probe-based confocal laser endomicroscopy (pCLE) is a promising modality for classifying polyp histology in vivo, but decision making in real-time is hampered by high-magnification targeting and by the learning curve for image interpretation. The aim of this study is to test the feasibility of a system combining the use of a low-magnification, wider field-of-view pCLE probe and a computer-assisted diagnosis (CAD) algorithm that automatically classifies colonic polyps.

METHODS

This feasibility study utilized images of polyps from 26 patients who underwent colonoscopy with pCLE. The pCLE images were reviewed offline by two expert and five junior endoscopists blinded to index histopathology. A subset of images was used to train classification software based on the consensus of two GI histopathologists. Images were processed to extract image features as inputs to a linear support vector machine classifier. We compared the CAD algorithm's prediction accuracy against the classification accuracy of the endoscopists.

RESULTS

We utilized 96 neoplastic and 93 non-neoplastic confocal images from 27 neoplastic and 20 non-neoplastic polyps. The CAD algorithm had sensitivity of 95%, specificity of 94%, and accuracy of 94%. The expert endoscopists had sensitivities of 98% and 95%, specificities of 98% and 96%, and accuracies of 98% and 96%, while the junior endoscopists had, on average, a sensitivity of 60%, specificity of 85%, and accuracy of 73%.

CONCLUSION

The CAD algorithm showed comparable performance to offline review by expert endoscopists and improved performance when compared to junior endoscopists and may be useful for assisting clinical decision making in real time.

Comprehensive Analysis of the Expression Profiles of Long Non-Coding RNAs with Associated ceRNA Network Involved in the Colon Cancer Staging and Progression

Long non-coding RNAs (lncRNAs) act as competing endogenous RNAs (ceRNAs) to compete with microRNAs (miRNAs) in cancer occurrence and development. However, the differential expression of RNAs and their ceRNA network during the development of colon cancer (CC) remains unclear. This study was aimed at comprehensive analysis of the lncRNAs and their ceRNA networks associated with CC. Whole transcriptome sequencing was performed on colorectal and adjacent normal tissues at different pathological stages. Forty-nine lncRNAs were differently expressed between the CC tissues and their adjacent normal tissues at all stages. Aberrant expression of lncRNA CDKN2B-AS1 and lncRNA MIR4435-2HG was confirmed by TCGA database. Moreover, 14 lncRNAs were differentially expressed between early and advance stages of the tumor tissues, and 117 miRNAs were specifically expressed in stage III & IV. Weighted gene co-expression network analysis of 17105 differently expressed mRNAs revealed that the mRNAs shown in module pink, midnight blue, black, and light cyan were related to TNM and pathological stage, and that these mRNAs were enriched in cancer related functions and pathways. As DElncRNA showed a trend of change similar to that of the DEmRNA and opposite to that of DEmiRNA, ceRNA network was constructed with 3 DEmiRNAs, 5 DElncRNAs, and 130 DEmRNAs. Real time PCR revealed that expression of MEG3 was decreased in the tumor tissues belonging to stage III and IV as compared to that in stage I. Moreover, hsa-miR-324-5p was upregulated, while FGFR3, PLCB4, and IKBKB were downregulated in the tumor tissues as compared to that in the adjacent normal tissues. Thus, this study revealed differentially expressed lncRNA between different stages of CC as well as suggested that lncRNA CDKN2B-AS1, MIR4435-2HG, and MEG3 may act as diagnostic biomarkers for the development of CC.

Further Defining the 2012 Multi-Society Task Force Guidelines for Surveillance of High-risk Adenomas: Is a 3-Year Interval Needed for All Patients?

GOALS

We set out to determine whether variation from this 3-year follow-up interval was associated with the finding of subsequent high-risk adenoma (HRA).

BACKGROUND

HRAs include the following: (1) an adenoma measuring ≥10 mm, (2) ≥3 adenomas found during a single procedure, and (3) an adenoma with high-grade dysplasia or villous architecture. The current Multi-Society Task Force guideline for timing of surveillance colonoscopy after removal of a HRA is 3 years.

STUDY

In 2016, we analyzed 495 patients who had a HRA removed during a 2008 colonoscopy. We compared the frequency of finding another HRA at follow-up intervals. We used the current guidelines as our referent group and performed logistical regression to identify whether any patient characteristics, procedural factors, or type of HRA predicted the development of HRAs on follow-up colonoscopy.

RESULTS

Individuals who followed-up at a median of 4.5 years did not have more HRA on follow-up compared with those who followed-up at 3 years (25.2% vs. 21.0%, P=0.062). These groups had similar baseline characteristics. Older individuals, male gender, having a history of polyps, and piecemeal resection of an HRA predicted future HRAs. The removal of ≥3 adenomas in 2008 as well as a combination of multiple, large, and advanced polyps showed a higher risk of future HRAs.

CONCLUSIONS

The 2012 Multi-Society Task Force recommendation of 3-year follow-up after removal of HRAs may not apply to all patients. We showed that a combination of patient demographics, procedural factors, and pathology best determines the surveillance colonoscopy interval.

The association between colorectal sessile serrated adenomas/polyps and subsequent advanced colorectal neoplasia

PURPOSE

Colorectal cancer (CRC) screening guidelines recommend increased surveillance of individuals with sessile serrated adenomas/polyps (SSA/Ps), but there is uncertainty about the risk associated with SSA/Ps. We aimed to determine the association between SSA/Ps and subsequent advanced colorectal neoplasia.

METHODS

This case-control study included Kaiser Permanente Washington (KPWA) members who received an index colonoscopy between 1/1/1998 and 12/31/2007, and had hyperplastic polyps (HPs) or SSA/Ps but no conventional adenomas according to study pathologist histologic review. Subsequent pathology reports and biopsies through 1/1/2013 were reviewed for advanced colorectal neoplasia. We linked to the Seattle-Puget Sound Surveillance Epidemiology and End Results (SEER) registry to identify additional CRC cases. We used generalized estimating equations with a logit link to estimate adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for advanced colorectal neoplasia, comparing those with SSA/Ps to those with HPs.

RESULTS

There were 161 individuals with index SSA/Ps, 548 with HPs, and 918 subsequent endoscopies included in analyses. Of those with index SSA/Ps, 19 had subsequent advanced colorectal neoplasia; 39 with HPs had subsequent advanced colorectal neoplasia. Compared to those with HPs, those with SSA/Ps were not statistically significantly more likely to have subsequent advanced colorectal neoplasia (adjusted OR 1.79; CI 0.98-3.28). Polyp size ≥ 10 mm, right colon location, and the presence of multiple serrated polyps were also not associated with advanced colorectal neoplasia.

CONCLUSIONS

Our results suggest that there is not a strong association between SSA/Ps and subsequent advanced colorectal neoplasia during the 5 years following SSA/P removal.

Update in Surveillance Recommendations in Individuals With Conventional Adenomas

PURPOSE OF REVIEW

Conventional adenomas, which are precursors to almost 70% of colorectal carcinomas, are found in more than one-third of screening colonoscopies. Surveillance recommendations, based on adenoma size, histology, and number, have evolved over the years and are currently reflective of index adenoma categorization as either low-risk (LRA) or high-risk (HRA). In this review, recent guideline recommendations as well as primary data that have helped to shape these recommendations are presented.

RECENT FINDINGS

Recent data have demonstrated that individuals with HRA on index exams may be at increased risk for CRC while those with LRA may have a minimal long-term risk for CRC, similar to those adults with normal index exams. Furthermore, the quality of the index exams is important for minimizing CRC risk. While individuals with HRA may require close surveillance intervals of 3 years, those with LRA or normal exams may need longer such as 10-year follow-up.

A Single-center Review of Pediatric Colonoscopy Quality Indicators

OBJECTIVES

Colonoscopy with terminal ileal (TI) intubation is an important diagnostic and therapeutic tool in the care of children with digestive diseases, especially in those with inflammatory bowel disease. Ileal intubation rate is a recognized quality indicator for pediatric colonoscopy. Our primary aim was to identify our single-center ileal intubation rate and to secondarily identify specific factors, including bowel preparation quality, procedure duration, and cecal intubation rates which affect successful ileal intubation and by extension, complete colonoscopy.

METHODS

A retrospective chart review of all colonoscopies in 2015 was completed, identifying 458 procedures. Sixty-seven patients were excluded, resulting in 391 colonoscopies reviewed.

RESULTS

We analyzed 391 colonoscopy procedures with a mean patient age of 14.4 ± 5.3 years. The most frequent primary indications for colonoscopy included abdominal pain with "red flag" symptoms (35.5%), known inflammatory bowel disease (25.1%), and isolated abdominal pain (11.5%). Ileal intubation was achieved in 91% of all colonoscopies, with a 94.4% cecal intubation rate. Failure of ileal and cecal intubations was classified into 4 categories: disease-related conditions, bowel preparation, technical aspects, and miscellaneous issues. Potentially modifiable factors accounted for the majority of cases of failed TI intubation. The mean colonoscopy time with and without successful TI intubation were 39 and 48.1 minutes, respectively.

CONCLUSIONS

Completion of colonoscopy to the TI is an essential part of a complete colonoscopy. TI intubation was possible in 91% of patients. This rate could potentially improve to 95% with optimization of modifiable factors such as improving bowel preparation or further refinement of endoscopic skills.

Yield of repeat colonoscopy in asymptomatic individuals with a positive fecal immunochemical test and recent colonoscopy

BACKGROUND AND AIMS

A fecal immunochemical test (FIT) is often repeated annually, even after a recent colonoscopy. However, there are no published data on the proper approach to FIT-positive patients after a recent colonoscopy. We compared colorectal cancer (CRC) and advanced colorectal neoplasia (ACRN) prevalence based on the interval since the last colonoscopy.

METHODS

We reviewed asymptomatic screenees aged ≥50 years who underwent FIT and colonoscopy.

RESULTS

Of 2228 FIT-positive participants, 514 had a colonoscopy less than 3 years before (group 1), 427 had a colonoscopy had a colonoscopy 3 to 10 years before (group 2), and 1287 had a colonoscopy >10 years before or no colonoscopy (group 3). The prevalence of CRC in groups 1, 2, and 3 was 2.1%, 1.6%, and 7.2%, respectively, and that for ACRN was 10.9%, 12.6%, and 26.0%, respectively. Even after adjusting for confounders, CRC and ACRN detection rates in group 1 were lower than those in group 3 but not lower than those in group 2. Among 6135 FIT-negative participants, the prevalence of CRC in the 3 groups was .7%, .4%, and 3.4%, respectively, and that for ACRN was 6.0%, 6.1%, and 14.7%, respectively. CRC and ACRN detection rates were significantly higher in FIT-positive participants than in FIT-negative participants in all 3 groups.

CONCLUSIONS

In FIT-positive patients who underwent colonoscopy within the prior 3 years, CRC and ACRN prevalence was not low. Our findings support the U.S. Multi-Society Task Force on the CRC screening recommendation that repeat colonoscopy be offered to patients with positive FIT results and recent colonoscopy.