Recommendations for Follow-Up After Colonoscopy and Polypectomy: A Consensus Update by the US Multi-Society Task Force on Colorectal Cancer

Reduced Adenoma Miss Rate With 9-Minute vs 6-Minute Withdrawal Times for Screening Colonoscopy: A Multicenter Randomized Tandem Trial

INTRODUCTION

Although the 9-minute mean withdrawal time (m-WT) is often reported to be associated with the optimal adenoma detection rate (ADR), no randomized trials of screening colonoscopy have confirmed the impact of a 9-minute m-WT on adenoma miss rate (AMR) and ADR.

METHODS

A multicenter tandem trial was conducted in 11 centers. Seven hundred thirty-three asymptomatic participants were randomized to receive segmental tandem screening colonoscopy with a 9-minute withdrawal, followed by a 6-minute withdrawal (9-minute-first group, 9MF, n = 366) or vice versa (6-minute-first group, 6MF, n = 367). The primary outcome was the lesion-level AMR.

RESULTS

The intention-to-treat analysis revealed that 9MF significantly reduced the lesion-level (14.5% vs 36.6%, P < 0.001) and participant-level AMR (10.9% vs 25.9%, P < 0.001), advanced adenoma miss rate (AAMR, 5.3% vs 46.9%, P = 0.002), multiple adenomas miss rate (20.7% vs 56.5%, P = 0.01), and high-risk adenomas miss rate (14.6% vs 39.5%, P = 0.01) of 6MF without compromising detection efficiency ( P = 0.79). In addition, a lower false-negative rate for adenomas ( P = 0.002) and high-risk adenomas ( P < 0.05), and a lower rate of shortening surveillance schedule ( P < 0.001) were also found in 9MF, accompanying with an improved ADR in the 9-minute vs 6-minute m-WT (42.3% vs 33.5%, P = 0.02). The independent inverse association between m-WT and AMR remained significant even after adjusting ADR, and meanwhile, 9-minute m-WT was identified as an independent protector for AMR and AAMR.

DISCUSSION

In addition to increasing ADR, 9-minute m-WT also significantly reduces the AMR and AAMR of screening colonoscopy without compromising detection efficiency.

FIT-based risk-stratification model effectively screens colorectal neoplasia and early-onset colorectal cancer in Chinese population: a nationwide multicenter prospective study

No fully validated risk-stratification strategies have been established in China where colonoscopies resources are limited. We aimed to develop and validate a fecal immunochemical test (FIT)-based risk-stratification model for colorectal neoplasia (CN); 10,164 individuals were recruited from 175 centers nationwide and were randomly allocated to the derivation (n = 6776) or validation cohort (n = 3388). Multivariate logistic analyses were performed to develop the National Colorectal Polyp Care (NCPC) score, which formed the risk-stratification model along with FIT. The NCPC score was developed from eight independent predicting factors and divided into three levels: low risk (LR 0-14), intermediate risk (IR 15-17), and high risk (HR 18-28). Individuals with IR or HR of NCPC score or FIT+ were classified as increased-risk individuals in the risk-stratification model and were recommended for colonoscopy. The IR/HR of NCPC score showed a higher prevalence of CNs (21.8%/32.8% vs. 11.0%, P < 0.001) and ACNs (4.3%/9.2% vs. 2.0%, P < 0.001) than LR, which was also confirmed in the validation cohort. Similar relative risks and predictive performances were demonstrated between non-specific gastrointestinal symptoms (NSGS) and asymptomatic cohort. The risk-stratification model identified 73.5% CN, 82.6% ACN, and 93.6% CRC when guiding 52.7% individuals to receive colonoscopy and identified 55.8% early-onset ACNs and 72.7% early-onset CRCs with only 25.6% young individuals receiving colonoscopy. The risk-stratification model showed a good risk-stratification ability for CN and early-onset CRCs in Chinese population, including individuals with NSGS and young age.

Incidence of colorectal cancer at different screening intervals after index colonoscopy and post-polypectomy: a meta-analysis of 811,181 participants

OBJECTIVES

To examine the evidence on the incidence of colorectal cancers (CRCs) at a follow-up screening colonoscopy (after index colonoscopy and post-polypectomy) in individuals with no adenoma, low-risk adenomas, and high-risk adenomas.

METHODS

We included studies reporting the incidence of CRCs at different screening intervals after index colonoscopy and post-polypectomy. The main outcome was pooled cumulative incidence rate of CRCs stratified by intervals of 3, 5, 10, and >10 years.

RESULTS

Fourteen studies with 811,181 participants were analyzed, including 10 multicenter studies and 3 national CRC screening programs. The cumulative incidence of CRCs was 0.63% (95% confidence interval [CI]: 0.30, 0.97) in the high-risk-adenoma group at 3 years, 0.37% (95% CI: 0.13, 0.61) and 0.67% (95% CI: 0.36, 0.99) in the low-risk-adenoma group at 5 and 10 years, respectively, and 0.32% (95% CI: 0.20, 0.45) and 0.50% (95% CI: 0.30, 0.69) in the no-adenoma-group at 10 and >10 years, respectively.

CONCLUSION

This meta-analysis summarizes the results of colonoscopy surveillance programs with detailed data support for different screening intervals. The data on date suggest that reasonable surveillance intervals are within 3 years for the high-risk-adenoma group, 5-10 years for the low-risk-adenoma group, and ≥10 years for the no-adenoma group.

Adenoma Detection Rate and Clinical Characteristics Influence Advanced Neoplasia Risk After Colorectal Polypectomy

BACKGROUND AND AIMS

Postpolypectomy risk stratification for subsequent metachronous advanced neoplasia (MAN) is imprecise and does not account for colonoscopist adenoma detection rate (ADR). Our aim was to assess association of ADR with MAN and create a prediction model for postpolypectomy risk stratification incorporating ADR and other factors.

METHODS

We conducted a retrospective cohort study of individuals with baseline polypectomy and subsequent surveillance colonoscopy from 2004 to 2016 within the U.S. Department of Veterans Affairs (VA). Clinical factors, polyp findings, and baseline colonoscopist ADR were considered for the model. Model performance (sensitivity, specificity, and area under the curve) for identifying individuals with MAN was compared with 2020 U.S. Multi-Society Task Force on Colorectal Cancer (USMSTF) surveillance recommendations.

RESULTS

A total of 30,897 individuals were randomly assigned 2:1 into independent model training and validation sets. Increasing age, male sex, diabetes, current smoking, adenoma number, polyp location, adenoma ≥10 mm or with tubulovillous/villous features, and decreasing colonoscopist ADR were independently associated with MAN. A range of 1.48- to 1.66-fold increased risk for MAN was observed for ADR in the lowest 3 quintiles (ADR <19.7%-39.3%) vs the highest quintile (ADR >47.0%). When the final model selected based on the training set was applied to the validation set, improved sensitivity and specificity over 2020 USMSTF risk stratification were achieved (P = .001), with an area under the curve of 0.62 (95% confidence interval, 0.60-0.64).

CONCLUSIONS

Colonoscopist ADR is associated with MAN. Combining clinical factors and ADR for risk stratification has potential to improve postpolypectomy risk stratification. Improving ADR is likely to improve postpolypectomy outcomes.

AGA White Paper: Challenges and Gaps in Innovation for the Performance of Colonoscopy for Screening and Surveillance of Colorectal Cancer

In 2018, the American Gastroenterological Association's Center for GI Innovation and Technology convened a consensus conference, entitled "Colorectal Cancer Screening and Surveillance: Role of Emerging Technology and Innovation to Improve Outcomes." The conference participants, which included more than 60 experts in colorectal cancer, considered recent improvements in colorectal cancer screening rates and polyp detection, persistent barriers to colonoscopy uptake, and opportunities for performance improvement and innovation. This white paper originates from that conference. It aims to summarize current patient- and physician-centered gaps and challenges in colonoscopy, diagnostic and therapeutic challenges affecting colonoscopy uptake, and the potential use of emerging technologies and quality metrics to improve patient outcomes.

Histology, Size, and Number of Advanced Polyps are Associated With Guideline-Discordant Surveillance Recommendations

Surveillance guidelines following polypectomy promote cost-effective reductions in future colorectal cancer (CRC) risk, but high nonadherence rates1 can have negative consequences on costs and effectiveness. Professional societies recommend a 3-year interval for patients with advanced colorectal polyps (ACPs), although few studies report provider adherence to surveillance intervals.2 This study evaluated rates and predictors of guideline-discordant recommendations for patients with ACPs.

Geographic Distribution and Time Trends of Colorectal Cancer in Brazil from 2005 to 2018

BACKGROUND

Colorectal cancer (CRC) is the third most common malignancy and the second leading cause of cancer-related death in the world. The aim of this study was to investigate the geographic distribution and time trends of CRC in Brazil.

METHODS

Data were retrospectively retrieved from January 2005 to December 2018 from the Brazilian Public Health System. The incidence and lethality rates of CRC per 100,000 inhabitants in each municipality were estimated from hospitalizations and in-hospital deaths and were classified by age, sex, and demographic features.

RESULTS

During the study period, the mean incidence of CRC estimated from hospitalizations and adjusted to available hospital beds more than tripled from 14.6 to 51.4 per 100,000 inhabitants (352%). Increases in CRC incidence were detected in all age ranges, particularly among people aged 50-69 years (266%). Incidence rates increased in all 5 macroregions, with a clear South to North gradient. The greatest changes in incidence and lethality rates were registered in small-sized municipalities. CRC lethality estimated from in-hospital deaths decreased similarly in both sexes, from 12 to 8% for males and females, from 2005 to 2018. The decline in lethality rates was seen in all age ranges, mainly in people aged 50 to 69 years (- 38%).

CONCLUSIONS

CRC incidence is increasing, predominantly above fifty years of age, and also in areas previously considered as having low incidence, but the increase is not paralleled by lethality rates. This suggests recent improvements in CRC screening programs and treatment, but also supports the spread of environmental risk factors throughout the country.

[Korean Guidelines for Postpolypectomy Colonoscopic Surveillance: 2022 Revised Edition]

Colonoscopic polypectomy is effective in decreasing the incidence and mortality of colorectal cancer (CRC). Premalignant polyps discovered during colonoscopy are associated with the risk of metachronous advanced neoplasia. Postpolypectomy surveillance is the most important method for managing advanced metachronous neoplasia. A more efficient and evidence-based guideline for postpolypectomy surveillance is required because of the limited medical resources and concerns regarding colonoscopy complications. In these consensus guidelines, an analytic approach was used to address all reliable evidence to interpret the predictors of CRC or advanced neoplasia during surveillance colonoscopy. The key recommendations state that the high-risk findings for metachronous CRC following polypectomy are as follows: 1) adenoma ≥10 mm in size; 2) 3-5 (or more) adenomas; 3) tubulovillous or villous adenoma; 4) adenoma containing high-grade dysplasia; 5) traditional serrated adenoma; 6) sessile serrated lesion (SSL) containing any grade of dysplasia; 7) serrated polyp of at least 10 mm in size; and 8) 3-5 (or more) SSLs. More studies are needed to fully comprehend the patients who are most likely to benefit from surveillance colonoscopy and the ideal surveillance interval to prevent metachronous CRC.

[Korean Guidelines for Postpolypectomy Colonoscopic Surveillance: 2022 Revised Edition]

Colonoscopic polypectomy is effective in decreasing the incidence and mortality of colorectal cancer (CRC). Premalignant polyps discovered during colonoscopy are associated with the risk of metachronous advanced neoplasia. Postpolypectomy surveillance is the most important method for managing advanced metachronous neoplasia. A more efficient and evidence-based guideline for postpolypectomy surveillance is required because of the limited medical resources and concerns regarding colonoscopy complications. In these consensus guidelines, an analytic approach was used to address all reliable evidence to interpret the predictors of CRC or advanced neoplasia during surveillance colonoscopy. The key recommendations state that the high-risk findings for metachronous CRC following polypectomy are as follows: 1) adenoma ≥10 mm in size; 2) 3-5 (or more) adenomas; 3) tubulovillous or villous adenoma; 4) adenoma containing high-grade dysplasia; 5) traditional serrated adenoma; 6) sessile serrated lesion (SSL) containing any grade of dysplasia; 7) serrated polyp of at least 10 mm in size; and 8) 3-5 (or more) SSLs. More studies are needed to fully comprehend the patients who are most likely to benefit from surveillance colonoscopy and the ideal surveillance interval to prevent metachronous CRC.

Sessile serrated lesions: Clinicopathological characteristics, endoscopic diagnosis, and management

The 2019 World Health Organization (WHO) Classification of Tumours of the Digestive System (5th edition) introduced the term "sessile serrated lesion" (SSL) to replace the term "sessile serrated adenoma/polyp" (SSA/P). SSLs are early precursor lesions in the serrated neoplasia pathway that result in colorectal carcinomas with BRAF mutations, methylation for DNA repair genes, a CpG island methylator phenotype, and high levels of microsatellite instability. Some of these lesions can rapidly become dysplastic or invasive carcinomas that exhibit high lymphatic invasion and lymph node metastasis potential. The 2019 WHO classification noted that dysplasia arising in an SSL most likely is an advanced polyp, regardless of the morphologic grade of the dysplasia. Detecting SSLs with or without dysplasia is critical; however, detection of SSLs is challenging, and their identification by endoscopists and pathologists is inconsistent. Furthermore, indications for their endoscopic treatment have not been established. Moreover, SSLs are considered to contribute to the development of post-colonoscopy colorectal cancers. Herein, the clinicopathological and endoscopic characteristics of SSLs, including features determined using white light and image-enhanced endoscopy, therapeutic indications, therapeutic methods, and surveillance are reviewed based on the literature. This information may lead to more intensive research to improve detection, diagnosis, and rates of complete resection of these lesions and reduce post-colonoscopy colorectal cancer rates.

Improved adenoma detection by a novel distal attachment device-assisted colonoscopy: a prospective randomized controlled trial

BACKGROUND AND AIMS

WingCap (A&A Medical Supply LLC, Seongnam, South Korea) is a novel distal attachment device for colonoscopy that combines a cap and an existing mucosal exposure device, such as Endocuff Vision (Arc Medical Design Ltd, Leeds, UK) and AmplifEYE (Medivators Inc, Minneapolis, Minn, USA). We aimed to investigate whether WingCap-assisted colonoscopy can improve the adenoma detection rate (ADR) and adenoma per colonoscopy (APC) and simultaneously shorten cecal intubation time compared with standard colonoscopy.

METHODS

We conducted a single-center, prospective, randomized controlled trial for outpatients aged ≥18 years undergoing colonoscopy. The primary outcome was ADR differences with the assistance of WingCap. Secondary outcomes were APC and other colonoscopy quality indicators, such as cecal intubation and withdrawal times.

RESULTS

In total, 537 patients were randomized for WingCap-assisted or standard colonoscopy. Their mean age was 59.3 years, and 48.5% were men. ADR was significantly higher in the WingCap group than in the control group (37.2% vs 26.6%, P = .012). APC was greater with WingCap than with standard colonoscopy (.72 ± 1.34 vs .45 ± 0.97, P = .008), prominently for nonpedunculated (.65 ± 1.25 vs .42 ± .95, P = .015) and diminutive (.42 ± .94 vs .20 ± .64, P = .002) adenomas. With WingCap, ADR and APC significantly increased for beginner endoscopists, whereas a modest increase was seen for experienced endoscopists. There were no differences in cecal intubation and withdrawal times between the 2 arms. No serious adverse event was associated with the use of WingCap.

CONCLUSIONS

WingCap-assisted colonoscopy was tolerable and efficacious for improving ADR and APC compared with standard colonoscopy, especially for nonpedunculated and diminutive adenomas and for beginner endoscopists. (Clinical trial registration number: KCT0005214.).

The risk of advanced neoplasia after polypectomy of one to two non-advanced adenomas less than 5 mm in size vs. normal colonoscopy

BACKGROUND

Current guidelines are inconsistent regarding the follow-up of patients with 1-2 diminutive (1-5 mm) non-advanced adenomas (DNAAs).

AIMS

To evaluate the risk of metachronous advanced neoplasia (AN), defined as cancer or advanced adenoma (AA), among patients with either normal colonoscopy or 1-2 DNAAs.

METHODS

A retrospective cohort study. Cohort I included 2,347 subjects with normal colonoscopy and 483 subjects with polypectomy of 1-2 DNAAs followed by colonoscopy. Cohort II included 11,881 subjects with normal colonoscopy and 1,342 subjects with 1-2 DNAAs followed through the cancer registry.

RESULTS

In cohort I, the rate of AN, cancer and AA among the polypectomy group vs. normal colonoscopy was 5.0% vs. 2.5%, Hazard Ratio (HR) 2.96 (95%CI [Confidence Interval]1.86-4.78) for AN; 0.6% vs. 0.3%, HR 3.32 (95%CI 0.85-13) for cancer; 4.3% vs. 2.2% HR 2.91 (95%CI 1.75-4.86) for AA. In cohort II, cancer occurred in 0.4% of the polypectomy group and 0.2% of the normal colonoscopy group, HR 2.27 (95% CI 0.56-9.19).

CONCLUSION

Compared to subjects with normal colonoscopy, subjects with polypectomy of 1-2 DNAAs, are at increased risk for AA when followed by colonoscopy, while the risk for cancer is non-significantly increased. Our findings suggest that patients with 1-2 DNNAs should be followed more tightly than patients with normal colonoscopy.

Randomized Controlled Trials of Artificial Intelligence in Clinical Practice: Systematic Review

BACKGROUND

The number of artificial intelligence (AI) studies in medicine has exponentially increased recently. However, there is no clear quantification of the clinical benefits of implementing AI-assisted tools in patient care.

OBJECTIVE

This study aims to systematically review all published randomized controlled trials (RCTs) of AI-assisted tools to characterize their performance in clinical practice.

METHODS

CINAHL, Cochrane Central, Embase, MEDLINE, and PubMed were searched to identify relevant RCTs published up to July 2021 and comparing the performance of AI-assisted tools with conventional clinical management without AI assistance. We evaluated the primary end points of each study to determine their clinical relevance. This systematic review was conducted following the updated PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) 2020 guidelines.

RESULTS

Among the 11,839 articles retrieved, only 39 (0.33%) RCTs were included. These RCTs were conducted in an approximately equal distribution from North America, Europe, and Asia. AI-assisted tools were implemented in 13 different clinical specialties. Most RCTs were published in the field of gastroenterology, with 15 studies on AI-assisted endoscopy. Most RCTs studied biosignal-based AI-assisted tools, and a minority of RCTs studied AI-assisted tools drawn from clinical data. In 77% (30/39) of the RCTs, AI-assisted interventions outperformed usual clinical care, and clinically relevant outcomes improved with AI-assisted intervention in 70% (21/30) of the studies. Small sample size and single-center design limited the generalizability of these studies.

CONCLUSIONS

There is growing evidence supporting the implementation of AI-assisted tools in daily clinical practice; however, the number of available RCTs is limited and heterogeneous. More RCTs of AI-assisted tools integrated into clinical practice are needed to advance the role of AI in medicine.

TRIAL REGISTRATION

PROSPERO CRD42021286539; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=286539.

Yield of Surveillance Colonoscopy in Older Adults with a History of Polyps: A Systematic Review and Meta-Analysis

BACKGROUND

The benefit of surveillance colonoscopy in older adults is not well described.

AIMS

To quantify the detection of colorectal cancer (CRC) and advanced polyps during surveillance colonoscopy in older adults with a history of colon polyps.

METHODS

We conducted a systematic review (MEDLINE, Cochrane Library, Web of Science, and Embase) for all published studies through May 2020 in adults age > 70 undergoing surveillance colonoscopy. The main outcome was CRC and advanced polyps detection. We performed meta-analysis to pool results by age (>70 vs. 50-70).

RESULTS

The search identified 6239 studies, of which 569 underwent full-text review and 64 data abstraction, of which 19 were included. The risk of detecting CRC (N = 11) was higher in those >70 compared to 50-70 (risk ratio 1.5 (95% CI 1.1-2.2); risk difference 0.8% (95% CI -0.2%-1.8%)). Similarly, the risk of detecting advanced polyps (N = 8) was higher in those >70 compared to 50-70 (risk ratio 1.3 (95% CI 1.2-1.3), risk difference 2.7% (95% CI 1.3%-4.0%)). Most studies did not stratify results by baseline polyp risk.

CONCLUSIONS

The detection of CRC and advanced polyps during surveillance colonoscopy in older individuals was higher than in younger controls; however, the absolute risk increase for both was small. These differences must be weighed against competing medical problems and limited life expectancy in older adults when making decisions about surveillance colonoscopy. More primary data on the risks of CRC and advanced polyps accounting for number of past colonoscopies, prior polyp risk, and duration of time since last polyp are needed.

Implementing precision medicine in endoscopy practice

In contrast to the "one-size-fits-all" approach, precision medicine focuses on providing health care tailored to individual variabilities. Implementing precision medicine in endoscopy practice involves selecting the appropriate procedures among the endoscopic armamentarium in the diagnosis and management of patients in a logical sequence, jointly considering the pretest probabilities of possible diagnoses, patients' comorbidities and preference, and risk-benefit ratio of the individual procedures given the clinical scenario. The aim of this review is to summarize evidence-supported strategies and measures that may enhance precision medicine in general endoscopy practice.

Adherence to Recommendations for Repeat Surveillance After Publication of New Postpolypectomy Guidelines

Background and Aims

The 2012 and 2020 US Multi-Society Task Force postpolypectomy guidelines have recommended progressively longer surveillance intervals for patients with low-risk adenomas (LRAs). These guidelines require data from past colonoscopies. We examined the impact of the 2012 guidelines for second surveillance on clinical practice, including the availability of prior colonoscopy data, with the aim of informing the implementation of the 2020 guidelines.

Methods

We identified surveillance colonoscopies at Stanford Health Care and the Palo Alto Veterans Affairs Health Care System in 3 periods: preguideline (March-August 2012), postguideline (January-June 2013), and delayed postguideline (July-September 2017). We collected data on the most recent previous colonoscopy, findings at the study entry surveillance colonoscopy, and recommendations for subsequent surveillance.

Results

Among 977 patients, the most recent prior colonoscopy data were available in 78% of preguideline, 78% of postguideline, and 61% of delayed postguideline cases (P < .001). The fraction of surveillance colonoscopy reports that deferred recommendations awaiting pathology increased from 6% to 11% in preguideline and postguideline to 59% in delayed postguideline cases (P < .001). Overall adherence to guidelines for subsequent surveillance was similar in all 3 periods (54%-67%; P = .089). In the postguideline and delayed postguideline periods combined, a 10-year subsequent surveillance interval was recommended in 0 of 29 cases with LRA followed by normal surveillance colonoscopy.

Conclusion

In patients undergoing surveillance, prior colonoscopy data were not always available and recommendations were often deferred awaiting pathology. Adherence to subsequent surveillance guidelines was suboptimal, especially for LRA followed by normal colonoscopy. Strategies addressing these gaps are needed to optimize implementation of the updated 2020 postpolypectomy guidelines.

Normal Gastrointestinal Mucosa at Biopsy and Overall Mortality: Nationwide Population-Based Cohort Study

BACKGROUND

Normal gastrointestinal (GI) mucosa on endoscopy has been linked to a lower risk of colorectal cancer (CRC) but its association to overall death is unknown.

METHODS

We identified 466,987 individuals with a first GI biopsy 1965-2016 with normal mucosa (60.6% upper GI and 39.4% lower GI) through all Swedish pathology departments (n = 28). They were individually matched to 2,321,217 reference individuals without a GI biopsy and also compared to 505,076 full siblings. Flexible parametric models were applied to estimate hazard ratio (HRs) and 95% confidence interval (95% CI) for death.

RESULTS

During a median follow-up of ~11 years, 85,859 (18.39%) of individuals with normal mucosa and 377,653 (16.27%) of reference individuals died. This corresponded to incidence rates of 147.56/10,000 vs 127.90/10,000 person-years respectively (rate difference: 19.66/10,000 person-years), with the multivariable-adjusted HR of 1.21 (95% CI: 1.20-1.22). Excess mortality was seen for both upper and lower biopsy with normal mucosa. Particularly higher HRs for death were seen in males, individuals biopsied when aged <40 years, those without a prior record of GI disease, and those with high education. Mortality risk was most increased in the first five years after biopsy (HR = 1.34; 95% CI: 1.32-1.36) but decreased thereafter. Having a GI biopsy with normal mucosa was associated with excess mortality from cardiovascular (CVD)disease (HR = 1.02; 95% CI: 1.01-1.03), cancer (HR = 1.58; 95% CI: 1.56-1.61), GI disease (HR = 1.65; 95% CI: 1.58-1.71), and other causes (HR = 1.10; 95% CI: 1.08-1.11). Sibling comparisons yielded similar results.

CONCLUSION

Compared with individuals without a GI biopsy, those with a normal GI biopsy due to clinical symptoms had a higher mortality particularly in the first five years after biopsy, and especially from GI disease and cancer.

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.

Colonoscopy Findings in FIT+ and mt-sDNA+ Patients versus in Colonoscopy-only Patients: New Hampshire Colonoscopy Registry Data

Few studies compare fecal immunochemical test (FIT) and multi-target stool DNA (mt-sDNA) outcomes in practice. We compared colonoscopy yield following FIT+ or mt-sDNA+ tests to colonoscopies without preceding stool tests in the comprehensive population-based New Hampshire Colonoscopy Registry (NHCR). Outcomes were any neoplasia and an ordered outcome: adenocarcinoma, advanced neoplasia (adenoma/serrated polyp ≥ 1 cm/villous/high-grade dysplasia), nonadvanced neoplasia, or normal. Our total sample included 306 mt-sDNA+ (average age ± SD 67.0 ± 7.9), 276 FIT+ (66.6 ± 8.7), and 50,990 colonoscopy-only patients (61.8 ± 8.1). Among average-risk patients (N = 240 mt-sDNA+, N = 194 FIT+, N = 26,221 colonoscopy only), mt-sDNA+ patients had a higher risk for any neoplasia (67.1%) compared with FIT+ (54.6%, P = 0.00098) or colonoscopy (40.8%, P < 0.0001). Severity of findings and histology subtypes differed across the three groups (P < 0.0001 for both), with a higher yield of advanced findings in mt-sDNA+ patients. In particular, clinically relevant serrated polyps (hyperplastic polyps ≥10 mm/traditional serrated adenomas/sessile serrated polyps) were detected at a higher frequency in mt-sDNA+ patients as compared with FIT+ or colonoscopy-only patients. Even after adjustment, patients with positive mt-sDNA [OR = 2.82; 95% confidence interval (CI), 2.00-4.02] or FIT+ tests (OR = 1.67; 95% CI, 1.19-2.36) were more likely to have histologically more advanced findings than colonoscopy alone. At follow-up colonoscopy, mt-sDNA+ tests were more likely to predict neoplasia than FIT+, largely due to increased detection of serrated polyps. Prevention Relevance: Colorectal cancer screening options include colonoscopy and stool-based tests, including the fecal immunochemical test (FIT) and the multi-target stool DNA (mt-sDNA) test which, if positive, must be followed by a colonoscopy. Assessing "real-world" outcomes of colonoscopies following positive stool tests can inform their clinical use. See related Spotlight, p. 417.

Prevalence of Adenomas on Surveillance Colonoscopies for Patients with a History of Colonic Polyps of Unknown Histology

BACKGROUND

Guidelines for surveillance colonoscopy depend on polyp histology. When patients present to a new healthcare system and report a personal history of "colon polyps," however, information on polyp histology is frequently unavailable.

AIMS

To assess adenoma prevalence in patients with a history of colonic polyps of unknown histology and to compare it to patients undergoing either screening colonoscopy or surveillance colonoscopy for known adenomatous polyps.

METHODS

This cohort study evaluated colonoscopies of patients ≥ 50 years of age over a 14-year period at a single institution. The exposure of interest was colonoscopy indication, categorized into three groups: screening colonoscopy, surveillance colonoscopy for history of colonic polyp(s) of unknown histology, and surveillance colonoscopy for history of adenoma(s). The primary outcome was adenoma detection rate. Multivariable logistic regression was used to assess the association between colonoscopy indication and adenoma detection rate.

RESULTS

Of 31,856 colonoscopies, the adenoma prevalence was 26.1% for patients undergoing screening colonoscopy, 32.9% for patients with a history of polyps of unknown histology, and 41.9% for patients with a history of known adenomatous polyps. Relative to screening colonoscopies, there were higher odds of adenoma detection in surveillance colonoscopies for polyps of unknown histology (aOR compared to screening 1.42, 95% CI 1.30-1.55) and even higher odds among surveillance colonoscopies for a history of adenoma (aOR compared to screening 1.89, 95% CI 1.75-2.05).

CONCLUSION

The adenoma prevalence on surveillance colonoscopy for patients with polyps of unknown histology was higher than that of screening colonoscopies but lower than that of surveillance colonoscopies for patients with adenomatous polyps.

Adenoma characteristics associated with post-polypectomy proximal colon cancer incidence: a retrospective cohort study

BACKGROUND

Colorectal cancer (CRC) screening is less effective at reducing cancer incidence in the proximal colon compared to the distal colorectum. We aimed to identify adenoma characteristics associated with proximal colon cancer (PCC).

METHODS

Endoscopy and pathology data for patients with ≥1 adenoma detected at baseline colonoscopy were obtained from 17 UK hospitals between 2001 and 2010. Multivariable Cox regression models were used to estimate adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) for PCC, and, for comparison, distal CRC incidence, by adenoma characteristics.

RESULTS

Among 18,431 patients, 152 and 105 developed PCC and distal CRC, respectively, over a median follow-up of 9.8 years. Baseline adenoma characteristics positively associated with PCC incidence included number (≥3 vs. < 3: aHR 2.10, 95% CI: 1.42-3.09), histology (tubulovillous/villous vs. tubular: aHR 1.61, 95% CI: 1.10-2.35) and location (any proximal vs. distal only: aHR 1.70, 95% CI: 1.20-2.42), for which there was borderline evidence of heterogeneity by subsite (p = 0.055). Adenoma dysplasia (high vs. low grade) was associated with distal CRC (aHR 2.42, 95% CI: 1.44-4.04), but not PCC (p-heterogeneity = 0.023).

CONCLUSIONS

Baseline adenoma number, histology and proximal location were independently associated with PCC and may be important to identify patients at higher risk for post-polypectomy PCC.

Screening for Colorectal Cancer

Colorectal cancer (CRC) is the second-leading cause of cancer death in the United States. Screening reduces CRC incidence and mortality. 2021 US Preventive Service Task Force (USPSTF) guidelines and available evidence support routine screening from ages 45 to 75, and individualized consideration of screening ages 76 to 85. USPSTF guidelines recommend annual guaiac fecal occult blood testing, annual fecal immunochemical testing (FIT), annual to every 3-year multitarget stool DNA-FIT, every 5-year sigmoidoscopy, every 10-year sigmoidoscopy with annual FIT, every 5-year computed tomographic colonography, and every 10-year colonoscopy as options for screening. The "best test is the one that gets done."

Non-optical polyp-based resect and discard strategy: A prospective clinical study

BACKGROUND

Post-polypectomy surveillance intervals are currently determined based on pathology results.

AIM

To evaluate a polyp-based resect and discard model that assigns surveillance intervals based solely on polyp number and size.

METHODS

Patients undergoing elective colonoscopies at the Montreal University Medical Center were enrolled prospectively. The polyp-based strategy was used to assign the next surveillance interval using polyp size and number. Surveillance intervals were also assigned using optical diagnosis for small polyps (< 10 mm). The primary outcome was surveillance interval agreement between the polyp-based model, optical diagnosis, and the pathology-based reference standard using the 2020 United States Multi-Society Task Force guidelines. Secondary outcomes included the proportion of reduction in required histopathology evaluations and proportion of immediate post-colonoscopy recommendations provided to patients.

RESULTS

Of 944 patients (mean age 62.6 years, 49.3% male, 933 polyps) were enrolled. The surveillance interval agreement for the polyp-based strategy was 98.0% [95% confidence interval (CI): 0.97-0.99] compared with pathology-based assignment. Optical diagnosis-based intervals achieved 95.8% (95%CI: 0.94-0.97) agreement with pathology. When using the polyp-based strategy and optical diagnosis, the need for pathology assessment was reduced by 87.8% and 70.6%, respectively. The polyp-based strategy provided 93.7% of patients with immediate surveillance interval recommendations vs 76.1% for optical diagnosis.

CONCLUSION

The polyp-based strategy achieved almost perfect surveillance interval agreement compared with pathology-based assignments, significantly reduced the number of required pathology evaluations, and provided most patients with immediate surveillance interval recommendations.

Active exercise after polypectomy reduces the risk of metachronous advanced colorectal neoplasm

BACKGROUND AND STUDY AIMS

Exercise is associated with a lower risk of colorectal neoplasm but its association with metachronous advanced colorectal neoplasm development after polypectomy remains unclear. We aimed to investigate associations between subjects' exercise habits and the risk of metachronous advanced colorectal neoplasm.

PATIENTS AND METHODS

This study analyzed subjects older than 40 years who received screening colonoscopy with polypectomy and surveillance colonoscopy between January 2009 and December 2016. All participants completed a standard questionnaire containing exercise habits before surveillance colonoscopy. Subjects' exercise habits were quantified as weekly exercise amounts (metabolic equivalents of task-day/week) and dichotomized (active/sedentary exercise habit) using averages as the cut-off point. The associations between incidence of metachronous advanced colorectal neoplasm and exercise habits were evaluated using Kaplan-Meier analysis and Cox regression models.

RESULTS

A total of 1820 subjects comprised the study cohort and 86 (4.73%) of them developed metachronous advanced colorectal neoplasm during the surveillance period. An active exercise habit after polypectomy was associated with a lower risk of metachronous advanced colorectal neoplasm (adjusted hazard ratio [aHR] 0.57, 95% confidence interval [CI] 0.35-0.91). Furthermore, this protective effect from exercise was specific for subjects having advanced neoplasm at screening colonoscopy (aHR 0.32, 95% CI 0.11-0.94).

CONCLUSIONS

An active exercise habit after polypectomy, a surrogate for a more active lifestyle, is associated with a lower risk for developing metachronous advanced colorectal neoplasm. A positive lifestyle modification, such as maintaining/establishing an active exercise habit, should be advised after polypectomy, especially for those with advanced colorectal neoplasm during screening.

Margin marking before colorectal endoscopic mucosal resection and its impact on neoplasia recurrence (with video)

BACKGROUND AND AIMS

Ablation of resection margins after EMR of large nonpedunculated colorectal polyps decreases recurrence. Margin marking before EMR (EMR-MM) may represent an alternative method to achieve a healthy resection margin. We aimed to determine the efficacy of EMR-MM in reducing neoplasia recurrence.

METHODS

We conducted a single-center historical control study of EMR cases (EMR-MM vs conventional EMR) for nonpedunculated polyps ≥20 mm between 2016 and 2021. For EMR-MM, cautery marks were placed along the lateral margins of the polyp with the snare tip. EMR was then performed to include resection of the healthy mucosa containing the marks. We compared recurrence at surveillance colonoscopy after EMR-MM versus historical control subjects. Multivariable logistic regression was performed to identify factors associated with recurrence.

RESULTS

Two hundred ten patients with 210 polyps (median size, 30 mm; interquartile range: 25-40) underwent EMR-MM (n = 74) or conventional EMR (n = 136). Patient and lesion characteristics were similar between the groups. At a median follow-up of 6 months, the recurrence rate was lower with EMR-MM (6/74; 8%) compared with historical control subjects (39/136; 29%) (P < .001). EMR-MM was not associated with an increased rate of adverse events. On multivariable analysis, EMR-MM remained the strongest predictor of recurrence (odds ratio, .20; 95% confidence interval, .13-.64; P = .003) aside from polyp size (odds ratio, 2.81; 95% confidence interval, 1.35-6.01; P = .008).

CONCLUSIONS

In this single-center historical control study, EMR-MM of large nonpedunculated colorectal polyps reduced the recurrence risk by 80% when compared with conventional EMR. This simple technique may provide an alternative to margin ablation.

Sessile serrated lesions in patients with adenoma on index colonoscopy do not increase metachronous advanced adenoma risk

OBJECTIVES

Post-polypectomy surveillance intervals should be determined based on index colonoscopy findings. However, the risk of metachronous lesions, resulting from the coexistence of adenoma and sessile serrated lesions (SSLs), has rarely been addressed. We evaluated the impact of synchronous SSL on the risk of metachronous lesions within similar adenoma risk groups.

METHODS

We retrieved individuals with one or more adenomas on index colonoscopy in a single-center retrospective cohort and stratified them into four groups depending on the presence of SSL and low-risk/high-risk adenoma (LRA/HRA). Participants who underwent surveillance colonoscopies at least 12 months apart were included. We compared the risks of metachronous lesions including HRA, advanced adenoma (AA), or SSL within similar adenoma risk groups according to the presence of SSL.

RESULTS

Overall 4493 individuals were included in the analysis. The risk of metachronous HRA/AA was not significantly higher in the adenoma with SSL group compared with the adenoma without SSL group, irrespective of LRA (HRA, 6/86 vs. 231/3297, P = 1.00; AA, 0/86 vs. 52/3297, P = 0.64) or HRA (HRA, 11/64 vs. 240/1046, P = 0.36; AA, 3/64 vs. 51/1046, P = 1.00). However, the risk of metachronous SSL in individuals with synchronous SSL was higher than that in those without SSL for both LRA (15/86 vs. 161/3297, P < 0.001) and HRA groups (11/64 vs. 61/1046, P = 0.002).

CONCLUSION

The presence of synchronous SSL did not increase the risk of metachronous HRA/AA, compared with isolated adenoma, but increased the risk of metachronous SSL.

Practice Patterns and Predictors of Stopping Colonoscopy in Older Adults With Colorectal Polyps

BACKGROUND & AIMS

Older adults with colorectal polyps undergo frequent surveillance colonoscopy. There is no specific guidance regarding when to stop surveillance. We aimed to characterize endoscopist recommendations regarding surveillance colonoscopy in older adults and identify patient, procedure, and endoscopist characteristics associated with recommendations to stop.

METHODS

This was a retrospective cohort study at a single academic medical center of adults aged ≥75 years who underwent colonoscopy for polyp surveillance or screening during which polyps were found. The primary outcome was a recommendation to stop surveillance. Predictors examined included patient age, sex, family history of colorectal cancer, polyp findings, and endoscopist sex and years in practice. Associations were evaluated using multilevel logistic regression.

RESULTS

Among 1426 colonoscopies performed by 17 endoscopists, 34.6% contained a recommendation to stop and 52.3% to continue. Older patients were more likely to receive a recommendation to stop, including those 80-84 years (odds ratio [OR], 7.7; 95% confidence interval [CI], 4.8-12.3) and ≥85 years (OR, 9.0; 95% CI, 3.3-24.6), compared with those 75-79 years. Family history of colorectal cancer (OR, 0.42; 95% CI, 0.24-0.74) and a history of low-risk (OR, 0.17; 95% CI, 0.11-0.24) or high-risk (OR, 0.02; 95% CI, 0.01-0.04) polyps were inversely associated with recommendations to stop. The likelihood of a recommendation to stop varied significantly across endoscopists.

CONCLUSIONS

Only 35% of adults ≥75 years of age are recommended to stop surveillance colonoscopy. The presence of polyps was strongly associated with fewer recommendations to stop. The variation in endoscopist recommendations highlights an opportunity to better standardize recommendations following colonoscopy in older adults.

Colorectal Neoplasia Detection in Individuals With Positive Multitarget Stool DNA Tests: Data From the New Hampshire Colonoscopy Registry

BACKGROUND

The US Preventive Services Task Force (USPSTF) includes multitarget stool DNA (mt-sDNA) testing as a colorectal cancer (CRC) screening option in average-risk individuals, but data on colonoscopy outcomes after positive mt-sDNA tests in community settings are needed.

AIM

The aim of this study was to investigate colonoscopy outcomes and quality following positive mt-sDNA in the population-based New Hampshire Colonoscopy Registry.

METHODS

We compared colonoscopy outcomes and quality between age-matched, sex-matched, and risk-matched patients from 30 endoscopy practices with and without a preceding positive mt-sDNA test. Main outcomes were colonoscopy findings of CRC, advanced noncancerous neoplasia, nonadvanced neoplasia, or normal examination. Quality measures included withdrawal time, bowel preparation quality, examination completion, and percentage of average-risk individuals with normal colonoscopies receiving a USPSTF-recommended 10 year rescreening interval.

RESULTS

Individuals with positive mt-sDNA tests (N=306, average age 67.0 y; 61.8% female) were significantly more likely than colonoscopy-only patients (N=918, 66.2 y; 61.8% female) to have CRC (1.3% vs. 0.4%) or advanced noncancerous neoplasia (27.1% vs. 8.2%) (P<0.0001). Neoplasia was found in 68.0% of patients having colonoscopy after a positive mt-sDNA test, (positive predictive value, was 68.0%), versus 42.3% of patients with colonoscopy only (P<0.0001). No significant differences in colonoscopy quality measures were observed between cohorts.

CONCLUSIONS

Colonoscopy after a positive mt-sDNA test was more frequently associated with CRC and colorectal neoplasia than colonoscopy alone. Positive mt-sDNA tests can enrich the proportion of colonoscopies with clinically relevant findings. Follow-up recommendations suggest that endoscopists do not inappropriately shorten rescreening intervals in mt-sDNA-positive patients with normal colonoscopy. These findings support the clinical utility of mt-sDNA for CRC screening in community practice.

The location-based resect and discard strategy for diminutive colorectal polyps: a prospective clinical study

BACKGROUND

Clinical implementation of the resect-and-discard strategy has been difficult because optical diagnosis is highly operator dependent. This prospective study aimed to evaluate a resect-and-discard strategy that is not operator dependent.

METHODS

The study evaluated a resect-and-discard strategy that uses the anatomical polyp location to classify colonic polyps into non-neoplastic or low risk neoplastic. All rectosigmoid diminutive polyps were considered hyperplastic and all polyps located proximally to the sigmoid colon were considered neoplastic. Surveillance interval assignments based on these a priori assumptions were compared with those based on actual pathology results and on optical diagnosis. The primary outcome was ≥ 90 % agreement with pathology in surveillance interval assignment.

RESULTS

1117 patients undergoing complete colonoscopy were included and 482 (43.1 %) had at least one diminutive polyp. Surveillance interval agreement between the location-based strategy and pathological findings using the 2020 US Multi-Society Task Force guideline was 97.0 % (95 % confidence interval [CI] 0.96-0.98), surpassing the ≥ 90 % benchmark. Optical diagnoses using the NICE and Sano classifications reached 89.1 % and 90.01 % agreement, respectively (P < 0.001), and were inferior to the location-based strategy. The location-based resect-and-discard strategy allowed a 69.7 % (95 %CI 0.67-0.72) reduction in pathology examinations compared with 55.3 % (95 %CI 0.52-0.58; NICE and Sano) and 41.9 % (95 %CI 0.39-0.45; WASP) with optical diagnosis.

CONCLUSION

The location-based resect-and-discard strategy achieved very high surveillance interval agreement with pathology-based surveillance interval assignment, surpassing the ≥ 90 % benchmark and outperforming optical diagnosis in surveillance interval agreement and the number of pathology examinations avoided.

Post-polypectomy follow-up recommendations by practicing academic gastroenterologists-does number of years in practice matter?

AIM

Colorectal cancer (CRC) is the third most deadly and fourth most common cancer worldwide. Early detection, resection, and appropriate surveillance of precursor polyps result in better outcomes. Colonoscopy is a safe, accurate, and effective tool for surveillance and follow-up of premalignant polyps. Recommended surveillance intervals are based on polyp, procedural, and patient-related factors. The United States Multi-Society Task Force (MSTF) on CRC publishes guidelines with periodic updates on surveillance. We sought to evaluate adherence to post-polypectomy surveillance guidelines by academic gastroenterologists at a high-volume center.

METHODS

One-year retrospective study evaluating compliance with post-polypectomy recommendations after average risk adult screening colonoscopies. Data was collected on number and size of polyps, quality of bowel prep, initial follow-up recommendations, polyp pathology, and follow-up recommendations. Correlation with the 2012 MSTF guidelines was also evaluated. Endoscopist experience was categorized as greater or less than 10 years of practice experience. Binomial regression was used to model the association between the providers' years of experience (<10 vs. >10) and the likelihood of agreement between initial assessment and post-pathology assessment.

RESULTS

There was a greater than 85% adherence to post-polypectomy surveillance guidelines, independent of endoscopist experience.

CONCLUSION

There is a high level of adherence to post-polypectomy guidelines by practicing academic gastroenterologists independent of post-fellowship clinical experience.

Tailoring Surveillance Colonoscopy in Patients With Advanced Adenomas

BACKGROUND & AIMS

Patients with advanced colorectal adenomas (AAs) are directed to undergo intensive surveillance. However, the benefit derived from surveillance may be outweighed by the risk of death from non-colorectal cancer (CRC) causes, leading to uncertainty on how best to individualize follow-up. The aim of this study was to derive a risk prediction model and risk index that estimate and stratify the risk for non-CRC cancer mortality (NCM) subsequent to diagnosis and removal of AA.

METHODS

We conducted a retrospective cohort study of veterans ≥40 years old who had colonoscopy for diagnostic or screening indications at 13 Veterans Affairs Medical Centers between 2002 and 2009 and had 1 or more AAs. The primary outcome was NCM using a fixed follow-up time period of 5 years. Logistic regression using the lasso technique was used to identify factors independently associated with NCM, and an index based on points from regression coefficients was constructed to estimate risk of 5-year NCM.

RESULTS

We identified 2943 veterans with AA (mean age [standard deviation] 63 [8.6] years, 98% male, 74% white), with an overall 5-year mortality of 16.7%, which was nearly all due to NCM (16.6%). Age, comorbidity burden, specific comorbid conditions, and hospitalization within the preceding year were independently associated with NCM. The risk prediction model had a goodness of fit (calibration) P value of .41 and c-statistic (discrimination) of 0.74 (95% confidence interval, 0.71-0.76). On the basis of comparable 5-year risks of NCM, the scores comprised 3 risk categories: low (score of 0-1), intermediate (score of 2-4), and high (score of ≥5), in which NCM occurred in 6.5%, 14.1%, and 33.2%, respectively.

CONCLUSIONS

We derived a risk prediction model that identifies veterans with advanced adenomas who are at high risk of NCM within 5 years, and who are thus unlikely to benefit from further surveillance.

Lipid-Based Nanoparticle Formulation of Diallyl Trisulfide Chemosensitizes the Growth Inhibitory Activity of Doxorubicin in Colorectal Cancer Model: A Novel In Vitro, In Vivo and In Silico Analysis

Garlic's main bioactive organosulfur component, diallyl trisulfide (DATS), has been widely investigated in cancer models. However, DATS is not suitable for clinical use due to its low solubility. The current study seeks to improve DATS bioavailability and assess its chemopreventive and chemosensitizing properties in an AOM-induced colorectal cancer model. The polyethylene glycol coated Distearoylphosphatidylcholine/Cholesterol (DSPC/Chol) comprising DATS-loaded DATSL and doxorubicin (DOXO)-encapsulated DOXL liposomes was prepared and characterized. The changes in the sensitivity of DATS and DOXO by DATSL and DOXL were evaluated in RKO and HT-29 colon cancer cells. The synergistic effect of DATSL and DOXL was studied by cell proliferation assay in the combinations of IC10, IC25, and IC35 of DATSL with the IC10 of DOXL. AOM, DATSL, and DOXL were administered to different groups of mice for a period of 21 weeks. The data exhibited ~93% and ~46% entrapment efficiency of DATSL and DOXL, respectively. The size of sham liposomes was 110.5 nm, whereas DATSL and DOXL were 135.5 nm and 169 nm, respectively. DATSL and DOXL exhibited significant sensitivity in the cell proliferation experiment, lowering their IC50 doses by more than 8- and 14-fold, respectively. However, the DATSL IC10, IC25, and IC35 showed escalating chemosensitivity, and treated the cells in combination with DOXL IC10. Analysis of histopathological, cancer marker enzymes, and antioxidant enzymes revealed that the high dose of DATSL pretreatment and DOXL chemotherapy is highly effective in inhibiting AOM-induced colon cancer promotion. The combination of DATSL and DOXL indicated promise as a colorectal cancer treatment in this study. Intermolecular interactions of DATS and DOXO against numerous cancer targets by molecular docking indicated MMP-9 as the most favourable target for DATS exhibiting binding energy of -4.6 kcal/mol. So far, this is the first research to demonstrate the chemopreventive as well as chemosensitizing potential of DATSL in an animal model of colorectal cancer.

Colorectal cancer screening preferences among physicians and individuals at average risk: A discrete choice experiment

BACKGROUND

Guidelines include several options for average-risk colorectal cancer (CRC) screening that vary in aspects such as invasiveness, recommended frequency, and precision. Thus, patient and provider preferences can help identify an appropriate screening strategy. This study elicited CRC screening preferences of physicians and individuals at average risk for CRC (IAR).

METHODS

IAR aged 45-75 years and licensed physicians (primary care or gastroenterology) completed an online discrete choice experiment (DCE). Participants were recruited from representative access panels in the US. Within the DCE, participants traded off preferences between screening type, screening frequency, true-positive, true-negative, and adenoma true positive (physicians only). A mixed logit model was used to obtain predicted choice probabilities for colonoscopy, multi-target stool DNA (mt-sDNA), fecal immunochemical test (FIT), and methylated septin 9 (mSEPT9) blood test.

RESULTS

Preferences of IAR and physicians were affected by screening precision and screening type. IAR also valued more regular screening. Physicians preferred colonoscopy (96.8%) over mt-sDNA (2.8%; p < 0.001), FIT (0.3%; p < 0.001) and mSEPT9 blood test (0.1%; p < 0.01). IAR preferred mt-sDNA (38.8%) over colonoscopy (32.5%; p < 0.001), FIT (19.2%; p < 0.001), and mSEPT9 blood test (9.4%; p < 0.001). IAR naïve to screening preferred non-invasive screening (p < 0.001), while the opposite was found for those who previously underwent colonoscopy or sigmoidoscopy.

CONCLUSIONS

While physicians overwhelmingly preferred colonoscopy, preferences of IAR were heterogenous, with mt-sDNA being most frequently preferred on average. Offering choices in addition to colonoscopy could improve CRC screening uptake among IAR. This study used a discrete choice experiment in the US to elicit preferences of physicians and individuals at average risk for colorectal cancer screening modalities and their characteristics.

Total polyp number may be more important than size and histology of polyps for prediction of metachronous high-risk colorectal neoplasms

BACKGROUND

To evaluate whether the risk of metachronous high-risk colorectal neoplasm (HR-CRN) differs according to the indication for surveillance colonoscopy.

METHODS

Patients who underwent polypectomy or endoscopic resection of colorectal neoplasms were enrolled and classified into three groups according to the indication for surveillance colonoscopy: advanced colorectal neoplasm (ACRN: adenoma ≥ 10 mm, adenoma with high-degree dysplasia and/or villous component), advanced serrated polyps (ASP: hyperplastic polyp or sessile serrated lesion ≥ 10 mm, traditional serrated polyp), and high-risk polyps (HRP: 3 or more adenomas or serrated polyps). The primary outcome was the development of metachronous HR-CRN, defined as ACRN, ASP, or HRP at the first follow-up colonoscopy.

RESULTS

In total, 367 patients were enrolled (ACRN group: N = 264; ASP group: N = 33; HRP group: N = 70). Among the 160 patients who underwent follow-up colonoscopy, 28 (18%) had HR-CRN. In univariable analysis, indication for surveillance colonoscopy was not found to be associated with the development of metachronous HR-CRN. Instead, the total polyp number at index colonoscopy showed a positive association with the risk of metachronous HR-CRN in trend analysis (p = 0.001). In multivariable analysis, the presence of 5 or more polyps at index colonoscopy was found to be associated with the risk of metachronous HR-CRN (OR, 2.575, p = 0.049) after adjusting for risk factors, such as obesity, diabetes, and smoking.

CONCLUSIONS

The risk of metachronous HR-CRN did not differ according to the main indications for surveillance colonoscopy. The presence of 5 or more polyps at index colonoscopy was the only risk factor for metachronous HR-CRN.

Endoscopic Mucosal Resection: Best Practices for Gastrointestinal Endoscopists

Endoscopic mucosal resection (EMR) is an endoscopic technique used to remove sessile or flat lesions from the gastrointestinal tract. This article reviews EMR and focuses on large colorectal polyps, which constitute the most common indication for EMR. Various methods of polyp evaluation can help gastroenterologists determine whether EMR is feasible and whether referral to an advanced endoscopist may be necessary. Techniques for performing EMR include conventional hot-snare EMR with submucosal injection and electro-cautery snare removal of colorectal lesions, as well as alternative EMR techniques such as cold-snare EMR and underwater EMR. Key adverse events associated with EMR include bleeding, perforation, and post-polypectomy coagulation syndrome. Finally, as residual or recurrent polyp formation is possible regardless of EMR technique, this article addresses the importance of surveillance post-EMR and the patients who are at highest risk for polyp recurrence.

Sessile Serrated Adenoma With Dysplasia of the Colon

OBJECTIVES

Sessile serrated adenomas with dysplasia (SSADs) of the colon are transitional lesions between sessile serrated adenomas (SSAs) and a subset of colorectal adenocarcinomas. We wished to gain insight into the relative percentages and significance of SSAD subtypes.

METHODS

Retrospective (2007-2012) clinicopathologic review of colorectal polyps initially regarded as having mixed serrated and dysplastic elements. SSADs were subdivided into those with cap-like adenomatous dysplasia (ad1), non-cap-like adenomatous dysplasia (ad2), serrated dysplasia (ser), minimal dysplasia (min), and dysplasia not otherwise specified (nos). MLH1 immunostaining was performed on many.

RESULTS

SSADser (7.7%) had a greater propensity for right colon, women, and MLH1 loss vs the entire cohort. SSAad1 (11.6%) had the least female preponderance, was least likely to have MLH1 loss, and was most likely to affect the left colorectum. SSAD with MLH1 loss was associated with an increased burden of SSAs in the background colon (P = .0003) but not tubular adenomas or hyperplastic polyps. Most SSADs (ad2 and nos groups, 80% combined) showed difficult-to-classify dysplasia, intermediate MLH1 loss rates, and intermediate clinical features.

CONCLUSIONS

While some trends exist, morphologically subclassifying SSADs is probably not justified in routine clinical practice. MLH1 loss portends a greater burden of SSAs in the background colon.

Development of a Large Colonoscopy-Based Longitudinal Cohort for Integrated Research of Colorectal Cancer: Partners Colonoscopy Cohort

BACKGROUND AND AIMS

Conventional adenomas (CAs) and serrated polyps (SPs) are precursors to colorectal cancer (CRC). Understanding metachronous cancer risk is poor due to lack of accurate large-volume datasets. We outline the use of natural language processing (NLP) in forming the Partners Colonoscopy Cohort, an integrated longitudinal cohort of patients undergoing colonoscopies.

METHODS

We identified endoscopy quality data from endoscopy reports for colonoscopies performed from 2007 to 2018 in a large integrated healthcare system, Mass General Brigham). Through modification of an established NLP pipeline, we extracted histopathological data (polyp location, histology and dysplasia) from corresponding pathology reports. Pathology and endoscopy data were merged by polyp location using a four-stage algorithm. NLP and merging procedures were validated by manual review of 500 pathology reports.

RESULTS

305,656 colonoscopies in 213,924 patients were identified. After merging, 76,137 patients had matched polyp data for 334,750 polyps. CAs and SPs were present in 86,707 (28.5%) and 55,373 (18.2%) colonoscopies. Among patients with polyps at index screening colonoscopy, 14,931 (33.4%) had follow-up colonoscopy (median 46.4, interquartile range 33.8-62.4 months); 91 (0.2%) and 1127 (2.5%) patients developed metachronous CRC and high-risk polyps (polyps ≥ 10 mm or CAs having high-grade dysplasia/villous/tublovillous histology or SPs with dysplasia). Genetic data were available for 23,787 (31.7%) patients with polyps from the Partners Biobank. The validation study showed a positive predictive value of 100% for polyp histology and locations.

CONCLUSION

We created the Partners Colonoscopy Cohort providing essential infrastructure for future studies to better understand the natural history of CRC and improve screening and post-polypectomy strategies.

Two vs One Forward View Examination of Right Colon on Adenoma Detection: An International Multicenter Randomized Trial

BACKGROUND & AIMS

Second forward view (SFV) examination of the right colon (RC) in colonoscopy was suggested to improve the adenoma detection rate (ADR), but multicenter data to inform its routine use remain limited. We performed an international multicenter randomized trial comparing SFV vs a standard single forward view examination of the RC on adenoma detection.

METHODS

Asymptomatic individuals undergoing screening or surveillance colonoscopies from 6 Asia Pacific regions were invited for study. A forward view examination of the RC was first performed in all patients, followed by randomization at the hepatic flexure to either SFV examination of the RC and standard withdrawal examination from the hepatic flexure to rectum, or a standard withdrawal colonoscopy (SWC) examination from the hepatic flexure to rectum. The primary outcome was RC ADR.

RESULTS

Between 2016 and 2019, there were 1011 patients randomized (SFV group, 502 patients; SWC group, 509 patients). Forty-five endoscopists performed the colonoscopies. The RC ADR was significantly higher in the SFV group than in the SWC group (27.1% vs 21.6%; P = .042). The whole-colon ADR was high in both groups (49.0% vs 45.0%; P =.201). The SFV examination identified 58 additional adenomas in 49 patients (9.8%), leading to a change in surveillance recommendations in 15 patients (3.0%). The median overall withdrawal time was 1.5 minutes longer in the SFV group (12.0 vs 10.5 min; P < .001). Older age, male sex, ever smoking, and longer RC withdrawal time were independent predictors of right-sided adenoma detection.

CONCLUSIONS

In this multicenter trial, SFV examination significantly increased the RC ADR in screening and surveillance colonoscopies. Routine RC SFV examination should be considered. ClinicalTrials.gov ID: NCT03121495.

Cancer Risk in Patients With and Relatives of Serrated Polyposis Syndrome and Sporadic Sessile Serrated Lesions

INTRODUCTION

Patients with serrated polyposis syndrome (SPS) and their first-degree relatives (FDRs) have increased colorectal cancer (CRC) risk. Patients with sporadic sessile serrated lesion (SSL) have risk for progression to CRC. Yet familial risks of common extracolonic cancers and even CRC in these cohorts are poorly understood. Our aim was to examine cancer risk for patients with SPS and sporadic SSL and their close and more distant relatives using a large population database.

METHODS

Patients with SPS (n = 59) from hereditary patient registries were eligible for study. Sporadic SSL (n = 754) and sex- and age-matched normal colonoscopy controls (n = 1,624) were selected from clinical data linked to the Utah Population Database. Cox models adjusting for the number of relatives, degree of relatedness, and person-years at risk were used to estimate CRC, extracolonic, and any-site adenocarcinoma/carcinoma cancer risk in patients and their relatives.

RESULTS

Compared with controls, CRC risk was elevated 10-fold in patients with SPS (P = 0.04) and 5-fold in their FDRs (P = 0.001). Any-site adenoma/carcinoma risk was increased 2.6-fold in FDRs of patients with SPS. No elevated risks of other common extracolonic cancers were observed in SPS and family members. The FDRs, second-degree relatives, and third-degree relatives of patients with both SSL and adenomatous polyps exhibited a 50% increased CRC risk.

DISCUSSION

Patients with SPS and their FDRs have an increased CRC risk, confirming other reports. Interestingly, patients with SSL were noted to have an increased risk of prostate cancer. Relatives of individuals with both sporadic SSL and adenomas, irrespective of size or dysplasia on examination, may have an elevated CRC risk, suggesting closer colonoscopy surveillance in this population.

Risk and Time Pattern of Recurrences After Local Endoscopic Resection of T1 Colorectal Cancer: A Meta-analysis

BACKGROUND & AIMS

Growing numbers of patients with T1 CRC are being treated with local endoscopic resection only and as a result, the need for optimization of surveillance strategies for these patients also increases. We aimed to estimate the cumulative incidence and time pattern of CRC recurrences for endoscopically treated patients with T1 CRC.

METHODS

Using a systematic literature search in PubMed, EMBASE, Web of Science and Cochrane Library (from inception till 15 May 2020), we identified and extracted data from studies describing the cumulative incidence of local or distant CRC recurrence for patients with T1 CRC treated with local endoscopic resection only. Pooled estimates were calculated using mixed-effect logistic regression models.

RESULTS

Seventy-one studies with 5167 unique, endoscopically treated patients with T1 CRC were included. The pooled cumulative incidence of any CRC recurrence was 3.3% (209 events; 95% CI, 2.6%-4.3%; I² = 54.9%), with local and distant recurrences being found at comparable rates (pooled incidences 1.9% and 1.6%, respectively). CRC-related mortality was observed in 42 out of 2519 patients (35 studies; pooled incidence 1.7%, 95% CI, 1.2%-2.2%; I² = 0%), and the CRC-related mortality rate among patients with recurrence was 40.8% (42/103 patients). The vast majority of recurrences (95.6%) occurred within 72 months of follow-up. Pooled incidences of any CRC recurrence were 7.0% for high-risk T1 CRCs (28 studies; 95% CI, 4.9%-9.9%; I² = 48.1%) and 0.7% (36 studies; 95% CI, 0.4%-1.2%; I² = 0%) for low-risk T1 CRCs.

CONCLUSIONS

Our meta-analysis provides quantitative outcome measures which are relevant to guidelines on surveillance after local endoscopic resection of T1 CRC.

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.

Analysis of Patients Undergoing Colonoscopies and the Importance of Exam Quality for Colorectal Cancer Screening

Objective To determine the impact of the quality of colonoscopy examination for colorectal cancer screening.

Methods Retrospective observational study of medical records from patients treated at the endoscopy and colonoscopy service of Hospital Universitário Evangélico Mackenzie (Curitiba, PR, Brazil) from January 2019 to January 2020.

Results The analysis was based on 337 medical records from patients with adenomas identified during colonoscopy, and 1,385 medical records from patients without adenomas. The estimated occurrence rate of diagnosis of adenoma during colonoscopy in the target population of the study was of 19.6%, with a 95% confidence interval ranging from 17.7 to 21.5%. Of the 337 patients with adenoma, 136 (40.4%) presented the advanced form. Statistical analysis indicated a significant association between the quality of colonoscopy preparation and test completion.

Conclusion The quality of colonoscopy images is a critical factor for colorectal cancer screening, as it leads to higher rates of adenoma detection and test completion.