British Society of Gastroenterology/Association of Coloproctology of Great Britain and Ireland/Public Health England post-polypectomy and post-colorectal cancer resection surveillance guidelines

UTP18-mediated p21 mRNA instability drives adenoma-carcinoma progression in colorectal cancer

Colorectal cancer (CRC) often develops slowly from adenoma, but the underlying mechanism remains unclear, hampering the prevention or treatment of colorectal adenoma-carcinoma progression. In this study, we use in-depth quantitative proteomics combined with survival analysis, revealing that the ribosome protein U3 small nucleolar RNA-associated protein 18 homolog (UTP18) is consistently upregulated in the progression of colorectal adenoma to carcinoma and is associated with adenoma recurrence, effective serodiagnosis, and poor prognosis of CRC. Furthermore, deSUMOylation induces the nucleocytoplasmic transport of UTP18, driving cell-cycle progression and tumorigenesis via mediation of the instability of p21 mRNA. In addition, the growth and ribosome biogenesis of adenoma organoids is found to be promoted by overexpression of UTP18. Thus, UTP18 contributes to multiple roles in adenogenesis and malignancy of CRC, suggesting that it could be a potential biomarker and drug target for colorectal adenoma and cancer.

Endoscopic surveillance after surgery for colorectal cancer

Colorectal cancer (CRC) is one of the most common cancers worldwide and its global incidence is rapidly increasing among adults younger than 50 years, especially in the 20-39 age group. Once a curative resection is achieved, surveillance is mandatory. Colonoscopy has a pivotal role aimed at resecting premalignant neoplasms and detecting cancer at a curable stage. In the current review, an update on the role of surveillance colonoscopy after CRC is provided, considered the most recent international guidelines and evidence published on this issue. In particular, several questions have been answered, why, how and how often colonoscopy should be performed, whether intensive surveillance is more effective than standard surveillance, how endoscopically resected T1 cancer should be followed, the different management existing between colon and rectal cancer, and, finally, how to improve the endoscopic surveillance. In a period of resource constraints, appropriateness will be mandatory, thus understanding how to optimize the role of colonoscopy in the surveillance of patients with a history of CRC is of crucial importance. Improving the quality of colonoscopy and identifying risk factors for recurrent and new-onset CRC, will allow us to individualize the surveillance program while sparing health care cost.

Through the Looking Glass: Surveillance Following Colonoscopic Polypectomy of Malignant Polyps

Introduction Colonoscopic polypectomy is a well-established screening and surveillance modality for malignant colorectal polyps. Following the detection of a malignant polyp, patients are either put on endoscopic surveillance or planned for a surgical procedure. We studied the outcome of colonoscopic excision of malignant polyps and their recurrence rates. Methods We performed a retrospective analysis over a period of five years (2015-2019) of patients who underwent colonoscopy and resection of malignant polyps. Size of polyp, follow-up with tumour markers, CT scan, and biopsy were considered individually for pedunculate and sessile polyps. We analysed the percentage of patients who underwent surgical resection, the percentage of patients who were managed conservatively, and the percentage of recurrence post-excision of malignant polyps. Results A total of 44 patients were included in the study. Of the 44 malignant polyps, most were present in the sigmoid colon at 43% (n=19), with the rectum containing 41% (n=18). The ascending colon accounted for 4.5% (n=2), transverse colonic polyps were 7% (n=3), and the descending colon polyps were 4.5% (n=2). Pedunculated polyps made up 55% (n=24). These were Level 1-3 based on Haggits classification; 14 were Haggits Level 1, eight were Haggits Level 2, and two were Haggits Level 3. The rest were sessile polyps making up 45% (n=20). Based on the Kikuchi classification, these were predominantly SM1 (n=12) and SM2 (n=8). Out of 44 cases, 11% (n=5) underwent surgical resection on follow-up in the form of bowel resection. This included three right hemicolectomies, one sigmoid colectomy, and one low anterior resection. Seven per cent (n=3) underwent endoscopic resection as trans-anal endoscopic mucosal resection (TEMS) and 82% (n=36) of the remaining cases were managed with regular follow-up and surveillance. Conclusions Colonoscopic polypectomy offers excellent benefits in detecting colorectal cancer and treating pre-malignant polyps. Colonoscopic polypectomy provides excellent benefits in colorectal cancer (CRC) detection and treatment of malignant polyps. However, it remains to be seen if post-polypectomy surveillance for low-risk polyp cancers would require a change in surveillance.

High serum riboflavin is associated with the risk of sporadic colorectal cancer

BACKGROUND

Experimental results indicate that riboflavin is involved in tumorigenesis. Data regarding the relationship between riboflavin and colorectal cancer (CRC) are limited, and findings vary between observational studies.

DESIGN

This was a case-control retrospective study.

OBJECTIVE

This study aimed to evaluate the associations between serum riboflavin level and sporadic CRC risk.

METHODS

In total, 389 participants were enrolled in this study - including 83 CRC patients without family history and 306 healthy controls - between January 2020 and March 2021 at the Department of Colorectal Surgery and Endoscope Center at Xinhua Hospital, Shanghai Jiao Tong University School of Medicine. Age, sex, body mass index, history of polyps, disease conditions (e.g., diabetes), medications, and eight other vitamins were used as confounding factors. Adjusted smoothing spline plots, subgroup analysis, and multivariate logistic regression analysis were conducted to estimate the relative risk between serum riboflavin levels and sporadic CRC risk. After fully adjusting for the confounding factors, an increased risk of colorectal cancer was suggested for individuals with higher levels of serum riboflavin (OR = 1.08 (1.01, 1.15), p = 0.03) in a dose-response relationship.

CONCLUSIONS

Our results support the hypothesis that higher levels of riboflavin may play a role in facilitating colorectal carcinogenesis. The finding of high levels of circulating riboflavin in patients with CRC warrants further investigation.

Clinicopathological features and expression of regulatory mechanism of the Wnt signaling pathway in colorectal sessile serrated adenomas/polyps with different syndrome types

BACKGROUND

Colorectal cancer (CRC) is the third most common cancer worldwide, with the fourth highest mortality among all cancers. Reportedly, in addition to adenomas, serrated polyps, which account for 15%-30% of CRCs, can also develop into CRCs through the serrated pathway. Sessile serrated adenomas/polyps (SSAs/Ps), a type of serrated polyps, are easily misdiagnosed during endoscopy.

AIM

To observe the difference in the Wnt signaling pathway expression in SSAs/Ps patients with different syndrome types.

METHODS

From January 2021 to December 2021, patients with SSAs/Ps were recruited from the Endoscopy Room of Shanghai Traditional Chinese Medicine-Integrated Hospital, affiliated with Shanghai University of Traditional Chinese Medicine. Thirty cases each of large intestine damp-heat (Da-Chang-Shi-Re, DCSR) syndrome and spleen-stomach weakness (Pi-Wei-Xu-Ruo) syndrome were reported. Baseline comparison of the general data, typical tongue coating, colonoscopy findings, and hematoxylin and eosin findings was performed in each group. The expression of the Wnt pathway-related proteins, namely β-catenin, adenomatous polyposis coli, and mutated in colorectal cancer, were analyzed using immunohistochemistry.

RESULTS

Significant differences were observed with respect to the SSAs/Ps size between the two groups of patients with different syndrome types (P = 0.001). The other aspects did not differ between the two groups. The Wnt signaling pathway was activated in patients with SSAs/Ps belonging to both groups, which was manifested as β-catenin protein translocation into the nucleus. However, SSAs/Ps patients with DCSR syndrome had more nucleation, higher β-catenin expression, and negative regulatory factor (adenomatous polyposis coli and mutated in colorectal cancer) expression (P < 0.0001) than SSA/P patients with Pi-Wei-Xu-Ruo syndrome. In addition, the SSA/P size was linearly correlated with the related protein expression.

CONCLUSION

Patients with DCSR syndrome had a more obvious Wnt signaling pathway activation and a higher risk of carcinogenesis. A high-quality colonoscopic diagnosis was essential. The thorough assessment of clinical diseases can be improved by combining the diseases of Western medicine with the syndromes of traditional Chinese medicine.

Microvesicular hyperplastic polyp and sessile serrated lesion of the large intestine: a biological continuum or separate entities?

The range of lesions with a serrated appearance within the large intestine has expanded and become more complex over the last 30 years. The majority of these were previously known as metaplastic polyps but are today called hyperplastic polyps (HPs). HPs show two main growth patterns: microvesicular and goblet cell-rich. The former type shows morphological and molecular similarities (eg, BRAF mutations) to the more recently described sessile serrated lesion (SSL). In this review, we debate whether these lesions represent a biological spectrum or separate entities. Whichever view is held, microvesicular HPs and SSLs are distinct from the goblet cell-rich HP and the traditional serrated adenoma (TSA), which may themselves share molecular changes (eg, KRAS mutations), with the goblet cell-rich HP representing a precursor to the TSA. Both SSLs and the goblet cell-rich HP-TSA pathway are routes to colorectal cancer within the serrated pathway and overlaps between them can occur, for example, a (BRAF-mutated) TSA may arise from an SSL.

Efficacy and accuracy of faecal sampling by a digital rectal examination for faecal immunochemical testing

AIM

A digital rectal examination (DRE) during routine assessment for patients with abdominal symptoms provides an opportunity to obtain faeces from the glove for faecal immunochemical testing (FIT). Here, we compared sampling via DRE to the standard faecal sampling by patients.

METHOD

Patients were recruited to a prospective observational cohort study between July 2019 and March 2020. Patients provided a sample for the FOB Gold Wide^® which was compared to a further sample taken at clinic via DRE. Clinicians reported whether they obtained a 'good' sample filling all the grooves, a 'poor' sample filling some of the grooves or no faecal sample. Cohen's kappa was used to compare percentage agreement around a negative threshold of <10 μg haemoglobin/g of faeces. Sensitivity for serious bowel disease (SBD) was calculated.

RESULTS

Of 596 patients who underwent attempted DRE sampling, there were 258 (43.3%) 'good' samples, 117 (19.6%) 'poor' samples and 221 (37.1%) with no sample to wipe in the grooves. Cohen's kappa dropped from 0.70 to 0.30 for the 'good' and 'poor' samples, respectively. Of those with DRE samples and definitive diagnostic outcomes, the sensitivity for SBD dropped significantly from 76.0% to 41.7% between 'good' and 'poor' samples, respectively (p = 0.041).

CONCLUSIONS

A 'good' sample obtained by DRE provides comparable results to samples obtained by patients. This creates potential benefit in speed and ease of testing for patients. However, not all DRE sampling attempts are successful, and the clinician must be satisfied that enough faeces is obtained to wipe adequately into all grooves.

Faecal immunochemical testing for haemoglobin in detecting bowel polyps in symptomatic patients: multicentre prospective cohort study

BACKGROUND

Measurement of faecal haemoglobin using faecal immunochemistry testing is recommended in patients presenting with symptoms suspicious for colorectal cancer, to aid in triage and prioritization of definitive investigations. While its role in colorectal cancer has been extensively investigated, the ability of faecal immunochemistry testing to detect adenomas in symptomatic patients is unclear.

METHODS

A multicentre prospective observational study was conducted between April 2017 and March 2019, recruiting adults from 24 hospitals across England and 59 general practices in London who had been urgently referred with suspected colorectal cancer symptoms. Each patient provided a stool sample for faecal immunochemistry testing, in parallel with definitive investigation. A final diagnosis for each patient was recorded, including the presence, size, histology, and risk type of colonic polyps. The outcome of interest was the sensitivity of faecal immunochemistry testing in detecting the presence of adenomas.

RESULTS

Of 3496 patients included in the analysis, 553 (15.8 per cent) had polyps diagnosed. Sensitivity of faecal immunochemistry testing for polyp detection was low across all ranges; with a cut-off for faecal haemoglobin of 4 µg/g or lower, sensitivity was 34.9 per cent and 46.8 per cent for all polyp types and high-risk polyps respectively. The area under the receiver operating characteristic curve in detection probability was relatively low for both intermediate-risk (0.63) and high-risk polyps (0.63).

CONCLUSION

While faecal immunochemistry testing may be useful in prioritizing investigations to diagnose colorectal cancer, if used as a sole test, the majority of polyps would be missed and the opportunity to prevent progression to colorectal cancer may be lost.

Risk Factors for Metachronous Colorectal Cancer or Advanced Adenomas After Endoscopic Resection of High-risk Adenomas

BACKGROUND & AIMS

Among the characteristics of high-risk adenomas (HRAs), some may predict a higher risk of metachronous advanced lesions. Our aim was to assess which HRA characteristics are associated with high risk of metachronous colorectal cancer (CRC) or advanced adenomas (AAs).

METHODS

We systematically searched Pubmed, EMBASE, and Cochrane for cohort studies and clinical trials of CRC or AA incidence at surveillance stratified by baseline lesion size, histology, and multiplicity. We calculated pooled relative risks (RRs) using a random-effects model. Heterogeneity was assessed with the I² statistic.

RESULTS

Fifty-five studies were included, with 936,540 patients with mean follow-up 5.4 ± 2.9 years. CRC incidence per 1000 person-years was 2.6 (2.1-3.0) for adenomas ≥20 mm, 2.7 (2.2-3.2) for high-grade dysplasia (HGD), 2.0 (1.8-2.3) for villous component, 0.8 (0.1-1.4) for ≥5 adenomas, 1.0 (0.7-1.2) for ≥3 adenomas. Metachronous CRC risk was higher in adenomas ≥20 mm vs 10 to 19 mm (RR, 2.08; 95% confidence interval [CI], 1.20-3.61), HGD vs low-grade dysplasia (RR, 2.89; 95% CI, 1.88-4.44), villous vs tubular (RR, 1.75; 95% CI, 1.33-2.31). No significant differences in CRC risk were found in ≥3 adenomas vs 1 to 2 (RR, 1.24; 95% CI, 0.84-1.83), nor in ≥5 adenomas vs 3 to 4 (RR, 0.79; 95% CI, 0.30-2.11). Compared with normal colonoscopy, RR for CRC risk was 2.61 (95% CI, 2.06-3.32) for ≥10mm, 6.62 (95% CI, 4.60-9.52) for HGD, 3.58 (95% CI, 2.24-5.73) for villous component, and 2.03 (95% CI, 1.40-2.94) for ≥3 adenomas. Similar trends were seen for metachronous AAs.

CONCLUSION

Metachronous CRC risk is highest in patients with baseline adenomas with ≥20 mm or HGD. Multiplicity does not seem to be associated with substantially higher CRC risk in the near term.

Lipidomic Profiling of Colorectal Lesions for Real-Time Tissue Recognition and Risk-Stratification Using Rapid Evaporative Ionization Mass Spectrometry

OBJECTIVE

Rapid evaporative ionization mass spectrometry (REIMS) is a metabolomic technique analyzing tissue metabolites, which can be applied intraoperatively in real-time. The objective of this study was to profile the lipid composition of colorectal tissues using REIMS, assessing its accuracy for real-time tissue recognition and risk-stratification.

SUMMARY BACKGROUND DATA

Metabolic dysregulation is a hallmark feature of carcinogenesis; however, it remains unknown if this can be leveraged for real-time clinical applications in colorectal disease.

METHODS

Patients undergoing colorectal resection were included, with carcinoma, adenoma and paired-normal mucosa sampled. Ex vivo analysis with REIMS was conducted using monopolar diathermy, with the aerosol aspirated into a Xevo G2S QToF mass spectrometer. Negatively charged ions over 600 to 1000 m/z were used for univariate and multivariate functions including linear discriminant analysis.

RESULTS

A total of 161 patients were included, generating 1013 spectra. Unique lipidomic profiles exist for each tissue type, with REIMS differentiating samples of carcinoma, adenoma, and normal mucosa with 93.1% accuracy and 96.1% negative predictive value for carcinoma. Neoplasia (carcinoma or adenoma) could be predicted with 96.0% accuracy and 91.8% negative predictive value. Adenomas can be risk-stratified by grade of dysplasia with 93.5% accuracy, but not histological subtype. The structure of 61 lipid metabolites was identified, revealing that during colorectal carcinogenesis there is progressive increase in relative abundance of phosphatidylglycerols, sphingomyelins, and mono-unsaturated fatty acid-containing phospholipids.

CONCLUSIONS

The colorectal lipidome can be sampled by REIMS and leveraged for accurate real-time tissue recognition, in addition to riskstratification of colorectal adenomas. Unique lipidomic features associated with carcinogenesis are described.

Timing of surveillance colonoscopy following malignant colorectal polypectomy in Queensland

INTRODUCTION

The management of malignant polyps presents a treatment challenge between a colorectal resection and polypectomy alone. Patients managed with polypectomy alone typically undergo surveillance for recurrent or metastatic disease, however, optimal timing of surveillance methods remains unclear. Guidelines recommend for completely resected malignant polyps, that a surveillance colonoscopy be perform 12 months from diagnosis. This study sought to clarify how patients with a malignant polyp were being colonoscopically surveilled if they did not undergo colorectal resection.

METHODS

A retrospective, population-wide cohort analysis of all patients from 2011 to 2019 was performed using data from the Queensland Oncology Repository. Patient, procedural and pathological data were extracted for all patients diagnosed with a malignant polyp and timing of the first surveillance endoscopy was calculated. Statistical analysis comparing the timing of surveillance colonoscopy across multiple patients, procedural and histological characteristics were assessed.

RESULTS

A total of 1646 patients were identified with a malignant polyp, with 797 patients managed with polypectomy and surveillance alone. The median time to surveillance endoscopy was 182 days with the mean 220.01 days. This was substantially sooner than the recommended clinical guidelines of 365 days. There were no patient or procedural characteristics which predicted a difference in the timing of surveillance colonoscopy. No pathological factors appeared to change the timing for surveillance endoscopy (P > 0.05).

CONCLUSION

Overall, patients had surveillance endoscopy procedures substantially earlier than guideline recommendations. However, evidence underlying these guidelines and other surveillance methods for malignant polyps are not strong. Future technological developments, including improvements in imaging techniques, may provide additional options for surveillance of malignant polyps.

Adherence to Post-polypectomy Surveillance Guidelines at a Large District General Hospital

Introduction In 2020, the British Society of Gastroenterologists (BSG), the Association of Coloproctology of Great Britain and Ireland (ACPGBI), and Public Health England (PHE) published joint guidelines regarding post-polypectomy surveillance. This study aimed to establish clinician adherence at the Royal Devon University Healthcare NHS Foundation Trust to the 2020 guidelines compared to the now-retired 2010 guidelines. Materials and Methods Data on 152 patients treated under the 2010 guidelines and 133 patients treated under the 2020 guidelines were collected retrospectively from the hospital's colonoscopy database. Data were analysed to determine whether patients who had a colonoscopy fulfilled BSG/ACPGBI/PHE guidelines for follow-up. Costs were estimated using the price of colonoscopy in the NHS National Schedule. Results Approximately 41.4% (63/152) of patients were adherent to the 2010 guidelines while 66.2% (88/133) of patients were adherent to the 2020 guidelines. The difference in adherence rate was 24.7% (95% confidence interval 13.5% - 35.9%, p<0.0001). Nearly 37% (35/95) of patients who would have been followed up under the 2010 guidelines did not receive any follow-up as a result of the 2020 guidelines. This represents a cost saving of £36,892.28 per year in our hospital. Approximately 47% (28/60) of patients treated under the 2020 guidelines had surveillance colonoscopy planned when the guidelines recommended no follow-up. If every clinician were fully adherent to the 2020 guidelines, then a further £29,513.82 per year would have been saved. Discussion and Conclusion Following the introduction of the 2020 guidelines, adherence to polyp surveillance guidelines increased in our hospital. However, nearly half of the colonoscopies were performed unnecessarily due to non-adherence. Furthermore, our results demonstrate that the 2020 guidelines have decreased the need for follow-up.

Adequate vitamin D level associated with reduced risk of sporadic colorectal cancer

Purpose

The effect of vitamin D level pertinent to colorectal cancer incidence, progression, or mortality risk is complicated, and study findings are mixed. Therefore, we evaluated whether serum vitamin D [25-hydroxyvitamin D, 25(OH)D] is associated with the incidence of sporadic colorectal cancer (CRC).

Methods

This study is a retrospective analysis of the relationship between serum 25(OH)D level and the risk of CRC. Age, sex, body mass index, history of polyp, disease conditions (i.e., diabetes), medications, and other eight vitamins were used as confounding factors. A total of 389 participants were enrolled in this study, including comprising 83 CRC patients without a family history and 306 healthy controls, between January 2020 and March 2021 at the Department of Colorectal Surgery and Endoscope Center at the Xinhua Hospital, Shanghai Jiao Tong University School of Medicine. Adjusted smoothing spline plots, subgroup analysis, and multivariate logistic regression analysis were conducted to estimate the relative risk between serum 25(OH)D and sporadic CRC risk.

Results

After fully adjusting the confounding factors, it was found that circulating 25(OH)D played a protective role in patients with CRC (OR = 0.76 [0.63, 0.92], p = 0.004) and that an adequate vitamin D level was significantly associated with a reduced CRC risk compared to vitamin D deficiency or sufficiency (OR = 0.31 [0.11, 0.9], p = 0.03). According to this study, statins did not affect the potential protective effects of vitamin D (OR = 1.02 [0.97, 1.08], p = 0.44) and may account for the inverse association between serum 25(OH)D and colorectal cancer.

Conclusion

An adequate level of serum 25(OH)D was associated with a reduced CRC risk, especially for the elderly. The finding on the absence of protective effect of vitamin D in the statin use subgroup, suggests it may be one of the substantial contributing confounders, and warrants further investigation.

Artificial intelligence empowers the second-observer strategy for colonoscopy: a randomized clinical trial

Background

In colonoscopy screening for colorectal cancer, human vision limitations may lead to higher miss rate of lesions; artificial intelligence (AI) assistance has been demonstrated to improve polyp detection. However, there still lacks direct evidence to demonstrate whether AI is superior to trainees or experienced nurses as a second observer to increase adenoma detection during colonoscopy. In this study, we aimed to compare the effectiveness of assistance from AI and human observer during colonoscopy.

Methods

A prospective multicenter randomized study was conducted from 2 September 2019 to 29 May 2020 at four endoscopy centers in China. Eligible patients were randomized to either computer-aided detection (CADe)-assisted group or observer-assisted group. The primary outcome was adenoma per colonoscopy (APC). Secondary outcomes included polyp per colonoscopy (PPC), adenoma detection rate (ADR), and polyp detection rate (PDR). We compared continuous variables and categorical variables by using R studio (version 3.4.4).

Results

A total of 1,261 (636 in the CADe-assisted group and 625 in the observer-assisted group) eligible patients were analysed. APC (0.42 vs 0.35, P = 0.034), PPC (1.13 vs 0.81, P < 0.001), PDR (47.5% vs 37.4%, P < 0.001), ADR (25.8% vs 24.0%, P = 0.464), the number of detected sessile polyps (683 vs 464, P < 0.001), and sessile adenomas (244 vs 182, P = 0.005) were significantly higher in the CADe-assisted group than in the observer-assisted group. False detections of the CADe system were lower than those of the human observer (122 vs 191, P < 0.001).

Conclusions

Compared with the human observer, the CADe system may improve the clinical outcome of colonoscopy and reduce disturbance to routine practice (Chictr.org.cn No.: ChiCTR1900025235).

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: adenoma ≥10 mm in size; 3 to 5 (or more) adenomas; tubulovillous or villous adenoma; adenoma containing high-grade dysplasia; traditional serrated adenoma; sessile serrated lesion containing any grade of dysplasia; serrated polyp of at least 10 mm in size; and 3 to 5 (or more) sessile serrated lesions. 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.

Green endoscopy: British Society of Gastroenterology (BSG), Joint Accreditation Group (JAG) and Centre for Sustainable Health (CSH) joint consensus on practical measures for environmental sustainability in endoscopy

GI endoscopy is highly resource-intensive with a significant contribution to greenhouse gas (GHG) emissions and waste generation. Sustainable endoscopy in the context of climate change is now the focus of mainstream discussions between endoscopy providers, units and professional societies. In addition to broader global challenges, there are some specific measures relevant to endoscopy units and their practices, which could significantly reduce environmental impact. Awareness of these issues and guidance on practical interventions to mitigate the carbon footprint of GI endoscopy are lacking. In this consensus, we discuss practical measures to reduce the impact of endoscopy on the environment applicable to endoscopy units and practitioners. Adoption of these measures will facilitate and promote new practices and the evolution of a more sustainable specialty.

NBI International Colorectal Endoscopic-derived high-confidence optical diagnosis of small polyps compared with histology: understanding errors to improve diagnostic accuracy

BACKGROUND AND AIMS

Developments in image-enhancing endoscopy and polyp classification systems have led to a number of gastroenterology societies endorsing an optical diagnosis (OD) approach for small polyps at colonoscopy. In this study we performed a root-cause analysis of ODs to determine the most likely causes of OD error.

METHODS

As part of a prospective feasibility study, DISCARD3 (Detect InSpect ChAracterise Resect and Discard 3), evaluating implementation and quality assurance of a "resect and discard" strategy for consecutive small polyps <10 mm, a root-cause analysis of 184 cases of high-confidence OD error was performed. In all cases, histopathology underwent a second blinded review and, where discrepancy persisted, further review with deeper levels.

RESULTS

After a root-cause analysis, 133 of 184 true OD errors were identified and classified into 4 types: A (OD, adenoma; histology, serrated), 45/133 (33.8%); B (OD, serrated; histology, adenoma), 55/133 (41.4%); C (OD, adenoma; histology, normal), 19/133 (14.3%); and D (OD, serrated; histology, normal), 14/133 (10.5%). The remaining 51 of 184 errors were because of a pathology error requiring deeper levels (43/184), pathology observer or laboratory error (7/184), or other error (1/184).

CONCLUSIONS

OD errors can be related to endoscopist-related factors such as poor photodocumentation, failures of current classification systems, and incomplete histology. We identified a subset of serrated polyps frequently misdiagnosed as adenomas ("pseudoadenomas") using the NBI International Colorectal Endoscopic (NICE) classification. An enhanced algorithm for OD is proposed based on the NICE classification including morphologic and adjunct polyp features.

Transanal minimally invasive surgery - A single-center experience

Background

Transanal minimally invasive surgery (TAMIS) was described in the literature 10 years ago. This procedure requires laparoscopic technical skills. It has been well accepted widely worldwide. TAMIS has been applied to multiple procedures, including excision for rectal polyps and cancer, with acceptable outcomes. The study aimed to assess the outcomes of TAMIS in a large district general hospital.

Methodology

A retrospective study on prospectively collected data on 52 consecutive patients of TAMIS performed in a single unit was conducted between May 2014 and February 2020. Data were collected on patient demographics, clinical diagnosis, peri-operative findings, pathological findings, adequacy of excision and complications. Patients were followed up as per the trust and national post-polypectomy guidelines.

Results

Among the 52 patients, TAMIS procedures were completed in 50 patients, of which 31 were female. The procedure was successful in 96.5% but had to abandon in two cases. There was no conversion to another procedure. Pre-operative indications were rectal polyps and one case was an emergency TAMIS in a patient who was bleeding following incomplete colonoscopic polypectomy. The final histology reported that the majority were benign polyps (46), and only 11 cases were malignant. The median distance of the lesion from the anal verge was 6 cm (3-10 cm). The median operative time was 55 min (8-175 min). A total of 45 (77.5%) lesions were completely excised and had negative microscopic margins. Most patients (64%) were discharged home the same day. No complications were observed at a median follow-up of 20 months (6-48 months). There was no mortality.

Conclusions

Our data suggest that TAMIS can be safely performed in a district general hospital for both benign and early rectal cancer. TAMIS was also able to control post-polypectomy bleeding and completion of rectal polypectomy. In selected cases, day-case TAMIS is safe and feasible.

Low Colon Capsule Endoscopy (CCE) False Negative Rate for Polyps Excluding Reader Error

BACKGROUND

CCE is a diagnostic tool lacking clinical data on false negative rates. We aimed to assess this rate and the reader/technical error breakdown.

METHODS

False negative CCEs were identified after comparing to a colonoscopy database. Missed pathology characteristics and study indications/quality were collated. Cases were re-read by experts and newly identified lesions/pathologies were verified by an expert panel and categorised as reader/technical errors.

RESULTS

Of 532 CCEs, 203 had an adequately reported comparative colonoscopy, 45 (22.2%) had missed polyps, and 26/45 (57.8%) reached the colonic section with missed pathology. Of the cases, 22 (84.6%) had adequate bowel preparation. Indications included 13 (50%) polyp surveillance, 12 (46%) GI symptoms, 1 (4%) polyp screening. CCE missed 18 (69.2%) diminutive polyps and 8 (30.8%) polyps ≥ 6 mm, 18/26 (69.2%) of these were adenomas. Excluding incomplete CCE correlates, colonoscopy total and significant polyp yield were 97/184 (52.7%) and 50/97 (51.5%), respectively. CCE total polyp and significant polyp false negative rate was 26.8% (26/97) and 16% (8/50), respectively. Following re-reading, reader and technical error was 20/26 (76.9%) and 6/26 (23.1%). Total and significant missed polyp rates were 20.6% (20/97) and 14% (7/50) for reader error, 6.2% (6/97) and 2% (1/50) for technical error.

CONCLUSIONS

False negative CCE rate is not insubstantial and should be factored into clinical decision making.

Implementation of optical diagnosis with a "resect and discard" strategy in clinical practice: DISCARD3 study

BACKGROUND AND AIMS

Optical diagnosis (OD) of polyps can be performed with advanced endoscopic imaging. For high-confidence diagnoses, a "resect and discard" strategy could offer significant histopathology time and cost savings. The implementation threshold is a ≥90% OD-histology surveillance interval concordance. Here we assessed the OD learning curve and feasibility of a resect and discard strategy for ≤5-mm and <10-mm polyps in a bowel cancer screening setting.

METHODS

In this prospective feasibility study, 8 bowel cancer screening endoscopists completed a validated OD training module and performed procedures. All <10-mm consecutive polyps had white-light and narrow-band images taken and were given high- or low-confidence diagnoses until 120 high-confidence ≤5-mm polyp diagnoses had been performed. All polyps had standard histology. High-confidence OD errors underwent root-cause analysis. Histology and OD-derived surveillance intervals were calculated.

RESULTS

Of 565 invited patients, 525 patients were included. A total of 1560 <10-mm polyps underwent OD and were resected and retrieved (1329 ≤5 mm and 231 6-9 mm). There were no <10-mm polyp cancers. High-confidence OD was accurate in 81.5% of ≤5-mm and 92.8% of 6-9-mm polyps. Sensitivity for OD of a ≤5-mm adenoma was 93.0% with a positive predictive value of 90.8%. OD-histology surveillance interval concordance for ≤5-mm OD was 91.3% (209/229) for U.S. Multi-Society Task Force, 98.3% (225/229) for European Society of Gastrointestinal Endoscopy, and 98.7% (226/229) for British Society of Gastroenterology guidelines, respectively.

CONCLUSIONS

A resect and discard strategy for high-confidence ≤5-mm polyp OD in a group of bowel cancer screening colonoscopists is feasible and safe, with performance exceeding the 90% surveillance interval concordance required for implementation in clinical practice. (Clinical trial registration number: NCT04710693.).

What size cutoff level should be used to implement optical polyp diagnosis?

BACKGROUND : The risk of advanced pathology increases with polyp size, as does the potential for mismanagement when optical diagnosis is used. This study aimed to evaluate the proportion of patients who would be assigned inadequate surveillance intervals when different size cutoffs are adopted for use of optical diagnosis. METHODS : In a post hoc analysis of three prospective studies, the use of optical diagnosis was evaluated for three polyp size groups: 1-3, 1-5, and 1-10 mm. The primary outcome was the proportion of patients in whom advanced adenomas were found and optical diagnosis resulted in delayed surveillance. Secondary outcomes included agreements between surveillance intervals based on high confidence optical diagnosis and pathology outcomes, reduction in histopathological examinations, and proportion of patients who could receive an immediate surveillance recommendation. RESULTS : We included 3374 patients (7291 polyps ≤ 10 mm) undergoing complete colonoscopies (median age 66.0 years, 75.2 % male, 29.6 % for screening). The percentage of patients with advanced adenomas and either 2- or 7-year delayed surveillance intervals (n = 79) was 3.8 %, 15.2 %, and 25.3 % for size cutoffs of 1-3, 1-5, and 1-10 mm polyps, respectively (P < 0.001). Surveillance interval agreements between pathology and optical diagnosis for the three groups were 97.2 %, 95.5 %, and 94.2 %, respectively. Total reductions in pathology examinations for the three groups were 33.5 %, 62.3 %, and 78.2 %, respectively. CONCLUSION : A 3-mm cutoff for clinical implementation of optical diagnosis resulted in a very low risk of delayed management of advanced neoplasia while showing high surveillance interval agreement with pathology and a one-third reduction in overall requirement for pathology examinations.

Elective Colorectal Surgery Service Provision during SARS-CoV-2 Pandemic

The SARS-Cov-2 pandemic and its immediate public health impact has caused severe disruption of regular medical care provision. The morbimortality of other diseases continues to affect people regardless of the viral infection. Indeed, it would be reasonable to assume that they have been aggravated by the period of most restrictive public health measures that were adopted against the virus. Recovery and maintenance of healthcare provision is required despite the ongoing threat. Therefore, it is critical to resume services in a structured and safe way, otherwise greater harm could come to our patients and to ourselves. The present article proposes to be a broad guide to the recovery and maintenance of elective outpatient, surgical and lower endoscopic services, aiding the colorectal surgeon in identifying risks, assessing their multiple dimensions, and implementing risk management strategies in a pragmatic and efficacious way.

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.

Risk of adenoma recurrence after polypectomy in patients younger than 50 years vs. 50 years old and over with diminutive or small adenomas

Background and aims

Current studies have shown that polyp recurrence occurs after colonic adenomas polypectomy (AP), but the difference in recurrence risk between patients in patients older than 50 years and younger than 50 years has not been clearly studied.

Methods

490 patients after AP were enrolled in the study. The patients were classified according to age (&lt;50 years old or ≥50 years old), and then further categorized according to the baseline adenoma characteristics: Group 1: 1–2 non-advanced adenomas (NAAs) 1–5 mm in size; Group 2: ≥3 NAAs, 1–5 mm; Group 3: 1–2 NAAs, 6–9 mm; Group 4: ≥3 NAAs, 6–9 mm; and Group 5: advanced adenomas.

Results

During a mean follow-up interval of 2.52 years (2.51 years for ≥50 years old and 2.55 years for patients &lt;50 years old), NAA recurrence was detected in 147 patients (30.0%). Overall, the hazard ratio (HR) for NAA recurrence after AP was higher in patients ≥50 years old than that in patients &lt;50 years old (HR, 1.774, P = 0.003). For patients &lt;50 years old, HRs (Group 2-5 vs. G1, respectively) for NAA recurrence were 0.744 (P = 0.773), 3.885 (P = 0.007), 5.337 (P = 0.003), and 3.334 (P = 0.015). For patients ≥50 years old, HRs (Group 2-5 vs. G1, respectively) for NAA recurrence were 1.033 (P = 0.965), 1.250 (P = 0.405), 2.252 (P = 0.015), and 1.887 (P = 0.009). For G1, the risk of NAA recurrence was significantly higher in patients ≥50 years old (HR, 2.932, P = 0.011) than that in patients &lt;50 years old; for G2–G5, the risk was similar in the two age groups (P &gt; 0.05).

Conclusions

For patients &lt;50 years old with less than 3 NAAs that are 1–5 mm in size, the recurrence rate of NAA is less than that of patients ≥50 years old with the same index colonoscopy findings. When the adenomas are ≥5 mm, or their number exceeds 3, they have similar recurrence risk as that for patients ≥50 years old.

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.

A Multi-Centre Study to Risk Stratify Colorectal Polyp Surveillance Patients Utilising Volatile Organic Compounds and Faecal Immunochemical Test

Simple Summary

A total of 15% of the annual colonoscopies are undertaken for polyp surveillance, and this causes strain on already stretched endoscopy services in the U.K. Hence, there is an urgent need to triage and prioritise patients with high-risk findings. The performance of the faecal immunochemical test is not adequate to be used within polyp surveillance. In light of this, we investigated the usefulness of urinary volatile organic compounds for the detection of high-risk findings. We confirmed that urinary volatile organic compounds can be used to triage patients with high-risk findings. It can be used alone or in combination with faecal immunochemical tests.

Abstract

(1) Background: The service capacity for colonoscopy remains constrained, and while efforts are being made to recover elective services, polyp surveillance remains a challenge. (2) Methods: This is a multi-centre study recruiting patients already on polyp surveillance. Stool and urine samples were collected for the faecal immunochemical test (FIT) and volatile organic compounds (VOC) analysis, and all participants then underwent surveillance colonoscopy. (3) Results: The sensitivity and specificity of VOC for the detection of a high-risk finding ((≥2 premalignant polyps including ≥1 advanced polyp or ≥5 premalignant polyps) were 0.94 (95% CI, 0.88 to 0.98) and 0.69 (95% CI, 0.64 to 0.75) respectively. For FIT, the sensitivity was (≥10 µg of haemoglobin (Hb) / g faeces) 0.54 (95% CI, 0.43 to 0.65) and the specificity was 0.79 (95% CI, 0.73 to 0.84). The probability reduction for having a high-risk finding following both negative VOC and FIT will be 24% if both tests are applied sequentially. (4) Conclusion: The diagnostic performance of VOC is superior to FIT for the detection of a high-risk finding. The performance further improves when VOC is applied together with FIT sequentially (VOC first and then FIT). VOC alone or the combination of VOC and FIT can be used as a triage tool for patients awaiting colonoscopy within a polyp surveillance population, especially in resource-constrained healthcare systems.

Trial protocol for COLO-DETECT: A randomized controlled trial of lesion detection comparing colonoscopy assisted by the GI Genius™ artificial intelligence endoscopy module with standard colonoscopy

AIM

Colorectal cancer is the second commonest cause of cancer death worldwide. Colonoscopy plays a key role in the control of colorectal cancer and, in that regard, maximizing detection (and removal) of pre-cancerous adenomas at colonoscopy is imperative. GI Genius™ (Medtronic Ltd) is a computer-aided detection system that integrates with existing endoscopy systems and improves adenoma detection during colonoscopy. COLO-DETECT aims to assess the clinical and cost effectiveness of GI Genius™ in UK routine colonoscopy practice.

METHODS AND ANALYSIS

Participants will be recruited from patients attending for colonoscopy at National Health Service sites in England, for clinical symptoms, surveillance or within the national Bowel Cancer Screening Programme. Randomization will involve a 1:1 allocation ratio (GI Genius™-assisted colonoscopy:standard colonoscopy) and will be stratified by age category (<60 years, 60-<74 years, ≥74 years), sex, hospital site and indication for colonoscopy. Demographic data, procedural data, histology and post-procedure patient experience and quality of life will be recorded. COLO-DETECT is designed and powered to detect clinically meaningful differences in mean adenomas per procedure and adenoma detection rate between GI Genius™-assisted colonoscopy and standard colonoscopy groups. The study will close when 1828 participants have had a complete colonoscopy. An economic evaluation will be conducted from the perspective of the National Health Service. A patient and public representative is contributing to all stages of the trial. Registered at ClinicalTrials.gov (NCT04723758) and ISRCTN (10451355). WHAT WILL THIS TRIAL ADD TO THE LITERATURE?: COLO-DETECT will be the first multi-centre randomized controlled trial evaluating GI Genius™ in real world colonoscopy practice and will, uniquely, evaluate both clinical and cost effectiveness.

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.

Robotic, self-propelled, self-steerable, and disposable colonoscopes: Reality or pipe dream? A state of the art review

Robotic colonoscopes could potentially provide a comfortable, less painful and safer alternative to standard colonoscopy. Recent exciting developments in this field are pushing the boundaries to what is possible in the future. This article provides a comprehensive review of the current work in robotic colonoscopes including self-propelled, steerable and disposable endoscopes that could be alternatives to standard colonoscopy. We discuss the advantages and disadvantages of these systems currently in development and highlight the technical readiness of each system to help the reader understand where and when such systems may be available for routine clinical use and get an idea of where and in which situation they can best be deployed.

Clinical evaluation of the OC-Sensor Pledia calprotectin assay

Objectives

Faecal calprotectin (f-Cal) and faecal haemoglobin (f-Hb) are important tests for evaluation of gastrointestinal disease. Samples for measurement of f-Hb are taken by the patient directly into a specimen collection device containing stabilising buffer, which can be placed directly onto the analyser in the laboratory. Samples for f-Cal are usually sent in screw top pots and often require time-consuming extraction procedures prior to analysis. OC-FCa calprotectin is a new assay which uses the same specimen collection device and analyser as our current f-Hb assay. Analytical evaluation has already shown it to perform well but to have a positive bias. This study was a clinical evaluation to investigate the diagnostic test performance and cut-off suitable for its use in the diagnosis of IBD.

Methods

OC-FCa calprotectin was measured in a convenience sample of 603 patients in whom f-Hb had been requested and was found to be ≥10 μg/g. Clinical outcomes were obtained from notes, radiological reports and endoscopy and histology reports.

Results

A total of 425 patients completed clinical investigations; IBD was diagnosed in 49 and other colorectal pathology in 161. Median f-Cal in patients with IBD was 1,660 μg/g, significantly different (p<0.01) from those with other colorectal pathology (192 μg/g) or normal findings (157 μg/g). ROC curve analysis showed AUC of 0.898 with sensitivity of 91.8% and specificity of 79.3% at a cut-off of 600 μg/g.

Conclusions

The new OC-FCa calprotectin assay performed well for the diagnosis of IBD using a cut-off of 600 μg/g.

Worrisome Trends in Young-Onset Colorectal Cancer: Now Is the Time for Action

Colorectal cancer (CRC) in the young adult population is of increasing incidence and concern. Since 1994, CRC incidence in individuals younger than 50 years has been increasing by 2% per year. The surge of CRC incidence in young adults is particularly alarming as the overall CRC frequency has been decreasing. Young-onset CRCs are characterized by more advanced stage at diagnosis, poorer cell differentiation, higher prevalence of signet ring cell histology, and left-colon sided location of the primary tumor. Genetic predisposition and heritable syndromes contribute to this trend, but perhaps more concerning is the majority of new diagnoses that involve no traceable genetic risk factors are sporadic. This review provides a summary of key aspects related to colorectal cancer in young adults, including epidemiology, etiology, genetics, clinical difficulties, early diagnosis, and prevention with emphasis on screening age.

Fecal Immunochemical Testing in Patients With Low-Risk Symptoms of Colorectal Cancer: A Diagnostic Accuracy Study

BACKGROUND

The fecal immunochemical test (FIT) is recommended for triaging primary care patients in England with low-risk symptoms of colorectal cancer (CRC). The evidence underpinning recommendations by the National Institute for Health and Care Excellence had limitations, with a paucity of primary care evidence. This study examines the diagnostic accuracy of FIT in a defined low-risk symptom primary care population.

PATIENTS AND METHODS

Consecutive symptomatic adult patients referred for a FIT between October and December 2019 were included. Patients were derived from 225 primary care practices in England. Serious colorectal diseases (CRC, high-risk polyps, and inflammatory bowel disease [IBD]) were identified through patient follow-up over 18 months, using both primary and secondary healthcare records. Performance characteristics of FIT are reported according to differing thresholds, including the currently recommended threshold of ≥10 μg hemoglobin per gram of feces (μg/g).

RESULTS

A total of 3,506 patients were included in the final analysis. Of these, 708 had a positive FIT result (≥10 μg/g). The prevalence of CRC was 1.3%. FIT positivity declined from 20.2% to 5.8% and 4.5% at cutoffs of 10, 80, and 120 μg/g, respectively. The sensitivity of FIT at ≥10 μg/g to detect CRC was 91.1% (95% CI, 77.9%-97.1%); its specificity was 80.7% (95% CI, 79.3%-82.0%); the positive predictive value (PPV) was 5.8% (95% CI, 4.2%-7.8%); and the negative predictive value (NPV) was 99.9% (95% CI, 99.6%-99.95%). The area under the receiver operating characteristic curve was 0.93 (0.91-0.96). PPV and specificity increased, whereas sensitivity and NPV decreased when serious colorectal diseases (CRC, high-risk polyps, and IBD) were combined. Age, sex, socioeconomic deprivation, and anemia did not significantly influence FIT sensitivity on subgroup analysis.

CONCLUSIONS

Utilization of FIT at a threshold ≥10 μg/g can safely triage patients with low-risk symptoms in primary care, with negative results effectively ruling out 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.

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.

Artificial intelligence-based measurement outperforms current methods for colorectal polyp size measurement

OBJECTIVES

An accurate polyp size estimation during colonoscopy is crucial to determine the surveillance interval and predict the risk of malignant progression. However, there is a high degree of subjectivity in estimating polyp size among endoscopists in clinical practice. We aimed to assess the efficacy of a novel method that uses artificial intelligence (AI) to measure the size of colon polyps and compare it with current approaches.

METHODS

Using the W-Net model for vessel segmentation and based on retinal image datasets (DRIVE, STARE, CHASE-DB, and HRF) and colonoscopy images, we developed the bifurcation-to-bifurcation (BtoB) distance measuring method and applied it to endoscopic images. Measurements were compared with those obtained by eight endoscopists (four expert and four trainees). Diagnostic ability and reliability were evaluated using Lin's concordance correlation coefficients (CCCs) and Bland-Altman analyses.

RESULTS

For both experts and trainees, visually estimated sizes of the same polyp were significantly inconsistent depending on the camera view used (P < 0.001). Bland-Altman analyses showed that there was a trend toward underestimation of the sizes of the polyps in both groups, especially for polyps larger than 10 mm. The new technique was highly accurate and reliable in measuring the size of colon polyp (CCC, 0.961; confidence interval 0.926-0.979), clearly outperforming the visual estimation and open biopsy forceps methods.

CONCLUSION

The new AI measurement method improved the accuracy and reliability of polyp size measurements in colonoscopy images. Incorporating AI might be particularly important to improve the efficiency of trainees at estimating polyp size during colonoscopy.

Risk of Colorectal Cancer and Advanced Polyps One Year After Excision of High-Risk Adenomas

BACKGROUND

Patients with multiple or large adenomas are considered to be high-risk for metachronous colorectal cancer.

OBJECTIVE

Evaluate the risks of detecting colorectal cancer, advanced adenoma, and advanced serrated polyps at 1-year surveillance colonoscopy in patients with >5 adenomas or adenomas >20 mm.

DESIGN

Descriptive, retrospective, multicentric, cohort study. We calculated the absolute risk of developing colorectal cancer, advanced adenomas, and advanced serrated polyps at the 1-year surveillance colonoscopy. Potential risk factors for advanced neoplasia at follow-up were evaluated with univariable and multivariable logistic regression analyses.

SETTINGS

This study included data from a multicenter cohort colorectal cancer screening program, conducted from January 2014 to December 2015, based on fecal immunochemical tests in Spain.

PATIENTS

We included 2119 participants with at least 1 adenoma ≥20 mm or ≥5 adenomas of any size.

MAIN OUTCOME MEASURES

We calculated the absolute risk of developing colorectal cancer, advanced adenomas, and advanced serrated polyps at the 1-year surveillance colonoscopy. Potential risk factors for advanced neoplasia at follow-up were evaluated with univariable and multivariable logistic regression analyses.

RESULTS

At 1 year, participants displayed 6 colorectal cancers (0.3%), 228 advanced adenomas (10.5%), and 58 advanced serrated polyps (2.7%). The adjusted analysis identified 2 factors associated with advanced neoplasia: >5 adenomas (odds ratio 1.53; 95% CI: 1.15-2.03; p = 0.004) and polyps in a proximal location (OR 1.52; 95% CI: 1.15-2.02; p = 0.004).

LIMITATIONS

First, the sample size was relatively small compared to other studies with similar aims. Another limitation was the lack of a comparison group, which could have provided more practical results in terms of surveillance recommendations.

CONCLUSIONS

The colorectal cancer detection rate at a 1-year colonoscopy surveillance was low among patients classified at high risk of advanced neoplasia. The risk factors for advanced neoplasia were ≥5 adenomas and proximal polyps at baseline. See Video Abstract at http://links.lww.com/DCR/B820 .

RIESGO DE CNCER COLORRECTAL Y DE PLIPOS AVANZADOS UN AO DESPUS DE LA RESECCIN DE ADENOMAS DE ALTO RIESGO

ANTECEDENTES:Los pacientes con adenomas múltiples o grandes se consideran de alto riesgo para desarrollar cáncer colorrectal metacrónico.OBJETIVO:Evaluar los riesgos de detectar cáncer colorrectal, adenoma avanzado y pólipos serrados avanzados en la colonoscopia de seguimiento al año, en pacientes con un número mayor o igual a 5 adenomas o adenomas de 20 mm o más.DISEÑO:Estudio descriptivo, retrospectivo, multicéntrico, de cohortes. Calculamos el riesgo absoluto de desarrollar cáncer colorrectal, adenomas avanzados y pólipos serrados avanzados en la colonoscopia de vigilancia al año. Los factores de riesgo potenciales para el desarrollo de una neoplasia avanzada en el seguimiento, fueron evaluados mediante un análisis de regresión logística univariable y multivariable.AJUSTES:Este estudio incluyó datos de un programa de cribado de cáncer colorrectal de cohorte multicéntrico, realizado entre enero de 2014 y diciembre de 2015, con base en pruebas inmunoquímicas de materia fecal, en España.PACIENTES:Incluimos 2119 participantes con al menos un adenoma ≥20 mm o con cinco o más adenomas de cualquier tamaño.PRINCIPALES MEDIDAS DE RESULTADO:Calculamos el riesgo absoluto de desarrollar cáncer colorrectal, adenomas avanzados y pólipos serrados avanzados en la colonoscopia de vigilancia al año. Los potenciales factores de riesgo para desarrollar una neoplasia avanzada en el seguimiento, se evaluaron mediante un análisis de regresión logística univariable y multivariable.RESULTADOS:Al año se encontraron en los pacientes participantes, 6 cánceres colorrectales (0,3%), 228 adenomas avanzados (10,5%) y 58 pólipos serrados avanzados (2,7%). Mediante el análisis ajustado se identificaron dos factores asociados con el desarrollo de neoplasia avanzada: un número igual o mayor a 5 adenomas (razón de probabilidades 1,53; IC del 95%: 1,15-2,03; p = 0,004) y la presencia de pólipos en una ubicación proximal (razón de probabilidades 1,52; IC del 95%: 1,15-2,02; p = 0,004).LIMITACIONES:Primero, el tamaño de la muestra fue relativamente pequeño en comparación con otros estudios con objetivos similares. Otra limitación fue la falta de un grupo comparativo, que podría haber proporcionado resultados más prácticos, en términos de recomendaciones de vigilancia.CONCLUSIÓNES:La tasa de detección de cáncer colorrectal mediante una colonoscopia de vigilancia al año, fue baja entre los pacientes clasificados como de alto riesgo de neoplasia avanzada. Los factores de riesgo para desarrollar una neoplasia avanzada fueron; un número igual o mayor a 5 adenomas y la presencia de pólipos proximales en la colonoscopia inicial de base. Consulte Video Resumen en http://links.lww.com/DCR/B820 . ( Traducción-Eduardo Londoño-Schimmer ).

Reducing the environmental footprint of gastrointestinal endoscopy: European Society of Gastrointestinal Endoscopy (ESGE) and European Society of Gastroenterology and Endoscopy Nurses and Associates (ESGENA) Position Statement

Climate change and the destruction of ecosystems by human activities are among the greatest challenges of the 21st century and require urgent action. Health care activities significantly contribute to the emission of greenhouse gases and waste production, with gastrointestinal (GI) endoscopy being one of the largest contributors. This Position Statement aims to raise awareness of the ecological footprint of GI endoscopy and provides guidance to reduce its environmental impact. The European Society of Gastrointestinal Endoscopy (ESGE) and the European Society of Gastroenterology and Endoscopy Nurses and Associates (ESGENA) outline suggestions and recommendations for health care providers, patients, governments, and industry. MAIN STATEMENTS 1: GI endoscopy is a resource-intensive activity with a significant yet poorly assessed environmental impact. 2: ESGE-ESGENA recommend adopting immediate actions to reduce the environmental impact of GI endoscopy. 3: ESGE-ESGENA recommend adherence to guidelines and implementation of audit strategies on the appropriateness of GI endoscopy to avoid the environmental impact of unnecessary procedures. 4: ESGE-ESGENA recommend the embedding of reduce, reuse, and recycle programs in the GI endoscopy unit. 5: ESGE-ESGENA suggest that there is an urgent need to reassess and reduce the environmental and economic impact of single-use GI endoscopic devices. 6: ESGE-ESGENA suggest against routine use of single-use GI endoscopes. However, their use could be considered in highly selected patients on a case-by-case basis. 7: ESGE-ESGENA recommend inclusion of sustainability in the training curricula of GI endoscopy and as a quality domain. 8: ESGE-ESGENA recommend conducting high quality research to quantify and minimize the environmental impact of GI endoscopy. 9: ESGE-ESGENA recommend that GI endoscopy companies assess, disclose, and audit the environmental impact of their value chain. 10:  ESGE-ESGENA recommend that GI endoscopy should become a net-zero greenhouse gas emissions practice by 2050.

Clinical utility of GI pathology data: implications for practising pathologists

Gastrointestinal (GI) tract pathology represents one of the largest individual specialties within cellular pathology departments globally. As with other specialties, clear communication with clinicians providing primary care for the patient is of utmost importance for optimal management and for appropriate use of resources such as endoscopy. A wide breadth of neoplastic and inflammatory conditions afflicts the GI tract. Here, we aim to illustrate how pathology reporting of GI tract specimens influences patient management and specifically how precise reporting of key parameters in different specimen types and different disease processes can directly impact patient care. We describe the potential clinical relevance of selected pathology data items pertinent to specific conditions and highlight areas of contention with respect to the significance of some pathology features. Recent guidelines are described where a change, for example, in diagnostic criteria for a condition is described, or criteria influencing further management such as endoscopic surveillance. The aim of this review is to focus on the clinical importance of careful written communication between the pathologist and primary clinician, illustrated by selective clinical scenarios involving the upper and lower GI tracts.

Faecal haemoglobin concentration in adenoma, before and after polypectomy, approaches the ideal tumour marker

BACKGROUND

Polypectomy may be performed at colonoscopy and then subsequent surveillance undertaken. It is thought that faecal haemoglobin concentration (f-Hb), estimated by quantitative faecal immunochemical tests (FIT), might be a useful tumour marker.

METHODS

Consecutive patients enrolled in colonoscopy surveillance were approached at two hospitals. A specimen for FIT was provided before colonoscopy and, ideally after 3 weeks, a second FIT sample from those who had polypectomy. A single FIT system (OC-Sensor io, Eiken Chemical Co., Ltd) was used to generate f-Hb.

RESULTS

1103 Patients were invited; 643 returned a FIT device (uptake: 58.3%). Four patients had known inflammatory bowel disease (IBD) and were excluded, leaving 639 (57.9%) with an age range of 25-90 years (median 64 years), 54.6% male. Of 593 patients who had a f-Hb result and completed colonoscopy, advanced neoplasia was found in 41 (6.9%); four colorectal cancer (CRC): 0.7% and 37 advanced adenoma (AA): 6.3%, and a further 127 (21.4%) had non-advanced adenoma (NAA). The median f-Hb was significantly greater in AA as compared to NAA; 6.0 versus 1.0 μg Hb/g faeces, p < 0.0001.134/164 (81.7%) of invited patients returned a second FIT device: 28 were patients with AA in whom median pre-polypectomy f-Hb was 19.2, falling to 3.5 μg Hb/g faeces post-polypectomy, p = 0.01, and 106 with NAA had median pre-polypectomy f-Hb 0.8 compared to 1.0 μg Hb/g faeces post-polypectomy, p = 0.96.

CONCLUSIONS

Quantitative FIT could provide a good tumour marker in post-polypectomy surveillance, reduce colonoscopy requirements and minimise potential risk to patients.