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

The natural history of sporadic non‐ampullary duodenal epithelial tumors: Can we wait and see?

Objectives

Methods

Results

Conclusion

≥3 Nonadvanced Adenomas are More Common in the Era of Contemporary Colonoscopy and Not Associated With Metachronous Advanced Neoplasia

INTRODUCTION

Data from standard definition colonoscopy era demonstrate patients with an advanced adenoma (≥10 mm, villous features or high-grade dysplasia) or ≥3 nonadvanced adenomas are considered high-risk for metachronous advanced neoplasia (MAN). Low-risk adenoma (LRA) patients are those with 1 to 2, <10 mm tubular adenomas. High definition colonoscopy, split-dose bowel preparation, and attention to adenoma detection enhance diminutive adenoma detection. We compared baseline adenoma characteristics between patients undergoing colonoscopy in a historic cohort (HC) and contemporary cohort (CC) to determine if number of patients with ≥3 nonadvanced adenomas are increased in CC, and if those features are associated with MAN in CC.

MATERIALS AND METHODS

Patients undergoing their first colonoscopy in HC (<2006) and CC (≥2006) at age 50 and above were identified through natural language processing. Multivariable regression analysis compared baseline adenoma characteristics between HC and CC, and determined the association between baseline characteristics and MAN in CC patients.

RESULTS

In total, 255,074 colonoscopies were performed between 1990 and 2015. A total of 9773 colonoscopies performed in the HC and 59,531 in the CC were included. At baseline, CC patients were more likely to have ≥3 nonadvanced adenomas [odds ratio (OR): 2.1, 95% confidence interval (CI): 1.7-2.6]. In 3,377 CC patients undergoing follow-up colonoscopy, the risk of MAN did not differ between patients with LRA versus those with ≥3 nonadvanced adenomas (6.3% vs. 4.6%, OR: 1.4, CI: 0.58-3.5) including 3-4 (6.1%, OR: 1.4, CI: 0.52-3.6) and ≥5 (7.7%, OR: 1.8, CI: 0.23-14.6), although few patients had ≥5 nonadvanced adenomas.

CONCLUSIONS

Colonoscopy in the contemporary era increases detection of patients with ≥3 nonadvanced adenomas, which do not increase the risk of MAN compared with LRA patients. A similar surveillance to LRA patients should be considered for those patients.

Are the current colonoscopy recommendations for interval surveillance in patients with polyps enough? Machine learning-augmented propensity score cohort analysis of 1840 patients

BACKGROUND

Colonoscopy remains the gold standard for screening and surveillance of colorectal neoplasms, and is associated with a lower risk of colorectal cancer (CRC)-related mortality. The current interval surveillance recommendations in patients with previous adenomas lack sufficient evidence. The prevalence of subsequent adenomas, and especially high-risk adenomas, during surveillance is not well known.

METHODS

The primary outcome of this study was to determine the prevalence of polyps upon surveillance colonoscopy in patients who have a history of adenomas on initial average-risk-screening colonoscopy, but then have a normal initial surveillance (second) colonoscopy between 2003 and 2017. This is the first known retrospective cohort study of adenoma detection rate (ADR) with sub-group analysis of patients with serial surveillance colonoscopies by abnormal and high-risk surveillance findings separately by prior abnormal colonoscopies and correct surveillance strategies based on the recent March 2020 updated guidelines. After ADR calculation, machine learning-augmented propensity score adjusted multivariable regression with augmented inverse-probability weighting propensity (AIPW) score analysis was used to assess the relationship between guideline adherence, as well as abnormal and high-risk surveillance findings.

RESULTS

A total of 1840 patients with pathologically confirmed adenomas or cancer on an initial average-risk-screening (first) colonoscopy met study criteria. 837 (45.5%) had confirmed adenomas on second colonoscopy, and 1003 (54.5%) had normal findings. Of 837 patients with polyps on both first and second colonoscopy, 423 (50.5%) had adenomas on third colonoscopy. Of the 1003 patients without polyps on second colonoscopy, 406 (40.5%) had confirmed adenomas on third colonoscopy. Guideline adherence was low at 9.18%, though was associated in propensity score adjusted multivariable regression with increased odds of an abnormal third (but not high-risk) colonoscopy, with comparable AIPW results.

CONCLUSION

This 14-year study demonstrates the ADR to be > 40% on the third colonoscopy for patients with adenomas on initial screening colonoscopy, who then have a normal second colonoscopy. Through advanced machine learning and propensity score analysis, we showed that correct adherence is associated with higher odds of abnormal, but not high-risk abnormal 3rd colonoscopy, with evidence that high-risk surveillance findings are reduced by providers shortening the time between surveillance colonoscopies in contrast to the guidelines for those for whom there is presumed greater clinical suspicion of eventual cancer. Larger prospective trials are needed to guide optimal surveillance for these patients.

Open-access colonoscopy quality indicators and patient perception using split-dose bowel preparation

Background and Aim

Open-access (OA) colonoscopies are defined as those scheduled without a gastrointestinal (GI) office visit. Past research has not focused on split preparation use and patient perception within OA. We aim to identify differences in bowel preparation (BP) adequacy, adenoma detection rate (ADR), self-reported compliance, and patient perception between OA and GI providers using split prep.

Methods

This was a cross-sectional study using split BP for colonoscopies. Patients completed a survey, and demographics, BP adequacy, and ADR were recorded. BP compliance was self-reported. Patients were asked three questions qualifying the BP instructions. Data were analyzed using chi square and Mann-Whitney tests by SPSS.

Results

BP adequacy was reported for 56 of 60 patients. Twenty-one participants (38%) were scheduled on OA, and 35 participants (62%) were scheduled after a GI office visit. Adequate BP was more frequent in 86% (18/21) of OA patients compared to 60% (21/35) in the GI group (P = 0.043). OA patients reported better review and explanation of the BP instructions compared to GI patients. There was no statistical difference between the demographics of the OA and GI groups or self-reported compliance and patient understanding of instructions.

Conclusion

OA scheduled colonoscopies were associated with more adequate BP. This could be explained by patients' self-motivation or an explanation of the importance of completing BP. This study supports the use of OA procedures as a standard of care.

Comparison of Risk of Metachronous Advanced Colorectal Neoplasia in Patients with Sporadic Adenomas Aged < 50 Versus ≥ 50 years: A Systematic Review and Meta-Analysis

No specific recommendations are available for the surveillance of young patients aged <50 years undergoing polypectomy. We aimed to compare the risk of metachronous advanced colorectal neoplasia (ACRN) between patients aged ≥50 years and those aged <50 years who underwent polypectomy. Studies published between January 1980 and June 2020 that examined the risk of metachronous ACRN were searched. We performed a meta-analysis for the metachronous ACRN risk in patients with sporadic colorectal adenomas according to the age groups (≥50 vs. <50 years). Eight individual studies were included in the meta-analysis. The risk of metachronous ACRN was higher in patients aged ≥50 years than in those aged <50 years without significant heterogeneity (odds ratio (OR) (95% CI): 1.62 (1.34–1.96), I² = 14%). The impact of the age group on the risk of metachronous ACRN was identified in both the low-risk (LRA) and high-risk (HRA) adenoma groups (≥50 vs. <50 years: LRA, OR 1.88 (95% CI 1.30–2.70); HRA, OR 1.50 [95% CI 1.13–2.00]). In conclusion, patients aged <50 years had a lower risk of metachronous ACRN than older patients. Young patients with sporadic adenomas do not require more intensive surveillance; rather, the surveillance interval may be extended in these patients.

Presence of Metabolic Syndrome and Thyroid Nodules in Subjects with Colorectal Polyps

Background

Thyroid nodules (TNs) and metabolic syndrome (MS) have been individually associated with colorectal polyps. However, the potential joint relationship between them in relation to colorectal polyps has not been fully evaluated. This study aimed to validate the association of TNs/MS and colorectal polyps/adenomas and to determine the risk of colonic polyps in patients with TNs/MS.

Material/Methods

A retrospective study was conducted on patients undergoing routine health checks in the First Affiliated Hospital of Wenzhou Medical University from July 2014 to August 2017. Univariate and multivariate logistic regression analyses were performed to identify independent risk factors for colorectal polyps/adenomas after adjusting for confounding factors. Then patients were divided into 4 groups according to whether they had TNs or MS. Relative excess risks of interaction, attributable proportion, and synergy index were used to determine the additive interaction of TNs and MS on colorectal polyps/adenomas.

Results

A total of 4514 eligible patients were included in this study. TNs and MS were confirmed to be independent risk factors for colorectal polyps/adenomas. Compared with the group of TNs(−)/MS(−), the odds ratios of TNs(+)/MS(+) in colorectal polyps (odds ratio [OR]: 3.031, 95% confidence interval [CI]: 2.262–4.062, P<0.05) or adenomas (OR: 2.894, 95% CI: 2.099–3.990, P<0.05) were significantly increased, and there was an interactive additive effect between TNs and MS.

Conclusions

TNs and MS have an associative and superimposing effect on the increased occurrence of colorectal adenomas. Colonoscopy screening should be advocated for patients with both of these diseases.

Clip placement to prevent delayed bleeding after colonic endoscopic mucosal resection (CLIPPER): study protocol for a randomized controlled trial

BACKGROUND

Endoscopic mucosal resection (EMR) for large colorectal polyps is in most cases the preferred treatment to prevent progression to colorectal carcinoma. The most common complication after EMR is delayed bleeding, occurring in 7% overall and in approximately 10% of polyps ≥ 2 cm in the proximal colon. Previous research has suggested that prophylactic clipping of the mucosal defect after EMR may reduce the incidence of delayed bleeding in polyps with a high bleeding risk.

METHODS

The CLIPPER trial is a multicenter, parallel-group, single blinded, randomized controlled superiority study. A total of 356 patients undergoing EMR for large (≥ 2 cm) non-pedunculated polyps in the proximal colon will be included and randomized to the clip group or the control group. Prophylactic clipping will be performed in the intervention group to close the resection defect after the EMR with a distance of < 1 cm between the clips. Primary outcome is delayed bleeding within 30 days after EMR. Secondary outcomes are recurrent or residual polyps and clip artifacts during surveillance colonoscopy after 6 months, as well as cost-effectiveness of prophylactic clipping and severity of delayed bleeding.

DISCUSSION

The CLIPPER trial is a pragmatic study performed in the Netherlands and is powered to determine the real-time efficacy and cost-effectiveness of prophylactic clipping after EMR of proximal colon polyps ≥ 2 cm in the Netherlands. This study will also generate new data on the achievability of complete closure and the effects of clip placement on scar surveillance after EMR, in order to further promote the debate on the role of prophylactic clipping in everyday clinical practice.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03309683 . Registered on 13 October 2017. Start recruitment: 05 March 2018. Planned completion of recruitment: 31 August 2021.

Interval colonoscopy following acute diverticulitis should not be discouraged yet: results from a retrospective cohort

BACKGROUND

Although included in some guidelines, the recommendation of interval colonoscopy after an acute diverticulitis (AD) episode has recently been questioned. In this study, we evaluated the incidence of colon cancer during the follow-up of an episode of AD.

METHODS

A retrospective review was carried out of patients with conservatively treated AD at our Institution (January 2011 to December 2018) with or without endoscopic study. Patients who had no colonoscopy performed were followed for two years. The demographic, clinical, radiological, follow-up and anatomopathological records were analysed. We determined CT scan validity for the differential diagnosis of CC and AD; sensibility, specificity, predictive values and likelihood ratios were calculated. Patients lost to follow-up and patients who had had colonoscopy in the previous three years were excluded.

RESULTS

This study included 285 patients with a mean age of 59 years. A total of 225 interval colonoscopies were performed and 60 patients without colonoscopy were followed up. There were 19 CC (6.7%) diagnosed, 14 with interval colonoscopy and 5 during follow-up; 8 (42.1%) happened in patients who had had an episode of uncomplicated AD. Although CT scan accuracy is high, 87.7%, positive and negative likelihood ratios were low, 4.67 and 0.64, respectively.

CONCLUSIONS

Interval colonoscopy should still be advisable after an episode of AD. The rationale for this statement is based on a non-negligible rate of hidden CC and an important uncertainty in the differential diagnosis.

NCCN Guidelines Insights: Colorectal Cancer Screening, Version 2.2020

The NCCN Guidelines for Colorectal Cancer (CRC) Screening describe various colorectal screening modalities as well as recommended screening schedules for patients at average or increased risk of developing sporadic CRC. They are intended to aid physicians with clinical decision-making regarding CRC screening for patients without defined genetic syndromes. These NCCN Guidelines Insights focus on select recent updates to the NCCN Guidelines, including a section on primary and secondary CRC prevention, and provide context for the panel's recommendations regarding the age to initiate screening in average risk individuals and follow-up for low-risk adenomas.

SPRY4-IT1 promotes survival of colorectal cancer cells through regulating PDK1-mediated glycolysis

Colorectal cancer (CRC) becomes the third leading cause of cancer-related deaths worldwide recently. The prognosis of CRC is still poor in decades, and targeted therapy is still a potential effective treatment. Long non-coding RNAs (lncRNAs) could regulate series of cellular functions and developmental processes. LncRNA-SPRY4-IT1 (GenBank ID AK024556) is derived from an intron of the SPRY4 gene, which was highly expressed in melanoma cells and affected the progression of multiple types of cancers. However, the mechanism of SPRY4-IT1 in CRC progression remains unclear. Herein, we found the high level of SPRY4-IT1 in human colorectal cancer (CRC) tissues and cells, and correlated with patients' prognosis. We further noticed that SPRY4-IT1 regulated CRC cell growth and glycolysis, and promoting PDK1 expression. Our data further confirmed that SPRY4-IT1 regulated CRC progression targeting PDK1. We therefore thought SPRY4-IT1 could serve as a promising molecular target for the treatment of CRC.

Does Colon Polyp Surveillance Improve Patient Outcomes?

Colon polyp surveillance now accounts for 25% of all colonoscopies performed. The evidence that colonoscopy surveillance reduces colorectal cancer (CRC) incidence or mortality is weak. The biology of the baseline lesions and quality of the baseline exam are two primary factors contributing to post-colonoscopy CRC. Prior recommendations for surveillance were based largely on the likelihood that patients with adenomas would develop advanced adenomas, a surrogate for CRC. There is now evidence that baseline colonoscopy findings are strongly associated with the risk of incidence or death from CRC. This evidence provides a basis for updated evidence-based recommendations for surveillance. In addition, there is also growing evidence that the quality of the baseline exam is an important predictor of the likelihood of developing post-colonoscopy CRC.