Establishment of standards for the referral of large nonpedunculated colorectal polyps: an international expert consensus using a modified Delphi process

BACKGROUND AND AIMS

Resection of colorectal polyps has been shown to decrease the incidence and mortality of colorectal cancer. Large nonpedunculated colorectal polyps are often referred to expert centers for endoscopic resection, which requires relevant information to be conveyed to the therapeutic endoscopist to allow for triage and planning of resection technique. The primary objective of this study was to establish minimum expected standards for the referral of large nonpedunculated colonic polyps for potential endoscopic resection.

METHODS

A Delphi method was used to establish consensus on minimum expected standards for the referral of large colorectal polyps among a panel of international endoscopy experts. The expert panel was recruited through purposive sampling, and 3 rounds of surveys were conducted to achieve consensus. Quantitative and qualitative data were analyzed for each round.

RESULTS

A total of 24 international experts from diverse continents participated in the Delphi study, resulting in consensus on 19 statements related to the referral of large colorectal polyps. The identified factors, including patient demographic characteristics, relevant medications, lesion factors, photodocumentation, and the presence of a tattoo, were deemed important for conveying the necessary information to therapeutic endoscopists. The mean scores for the statements, which were scored on a scale of 1 to 10, ranged from 7.04 to 9.29, with high percentages of experts considering most statements as a very high priority. Subgroup analysis according to continent revealed some variations in consensus rates among experts from different regions.

CONCLUSIONS

The identified consensus statements can aid in improving the triage and planning of resection techniques for large colorectal polyps, ultimately contributing to the reduction of colorectal cancer incidence and mortality.

An artificial intelligence-assisted system versus white light endoscopy alone for adenoma detection in individuals with Lynch syndrome (TIMELY): an international, multicentre, randomised controlled trial

BACKGROUND

Computer-aided detection (CADe) systems for colonoscopy have been shown to increase small polyp detection during colonoscopy in the general population. People with Lynch syndrome represent an ideal target population for CADe-assisted colonoscopy because adenomas, the primary cancer precursor lesions, are characterised by their small size and higher likelihood of showing advanced histology. We aimed to evaluate the performance of CADe-assisted colonoscopy in detecting adenomas in individuals with Lynch syndrome.

METHODS

TIMELY was an international, multicentre, parallel, randomised controlled trial done in 11 academic centres and six community centres in Belgium, Germany, Italy, and Spain. We enrolled individuals aged 18 years or older with pathogenic or likely pathogenic MLH1, MSH2, MSH6, or EPCAM variants. Participants were consecutively randomly assigned (1:1) to either CADe (GI Genius) assisted white light endoscopy (WLE) or WLE alone. A centre-stratified randomisation sequence was generated through a computer-generated system with a separate randomisation list for each centre according to block-permuted randomisation (block size 26 patients per centre). Allocation was automatically provided by the online AEG-REDCap database. Participants were masked to the random assignment but endoscopists were not. The primary outcome was the mean number of adenomas per colonoscopy, calculated by dividing the total number of adenomas detected by the total number of colonoscopies and assessed in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, NCT04909671.

FINDINGS

Between Sept 13, 2021, and April 6, 2023, 456 participants were screened for eligibility, 430 of whom were randomly assigned to receive CADe-assisted colonoscopy (n=214) or WLE (n=216). 256 (60%) participants were female and 174 (40%) were male. In the intention-to-treat analysis, the mean number of adenomas per colonoscopy was 0·64 (SD 1·57) in the CADe group and 0·64 (1·17) in the WLE group (adjusted rate ratio 1·03 [95% CI 0·72-1·47); p=0·87). No adverse events were reported during the trial.

INTERPRETATION

In this multicentre international trial, CADe did not improve the detection of adenomas in individuals with Lynch syndrome. High-quality procedures and thorough inspection and exposure of the colonic mucosa remain the cornerstone in surveillance of Lynch syndrome.

FUNDING

Spanish Gastroenterology Association, Spanish Society of Digestive Endoscopy, European Society of Gastrointestinal Endoscopy, Societat Catalana de Digestologia, Instituto Carlos III, Beca de la Marato de TV3 2020. Co-funded by the European Union.

Adenoma detection rate and tolerability of two ultra-low volume bowel preparations in screening: a noninferiority randomized controlled trial

BACKGROUND AND AIMS

The adenoma detection rate (ADR), recognized as a surrogate marker for colorectal cancer incidence and mortality reduction, is closely linked to the efficacy of bowel cleansing. However, there is a dearth of evidence examining the impact on ADR when employing two distinct very low-dose bowel cleansing products. This study sought to compare ADR in a fecal immunochemical occult blood testing (iFOBT) based organized screening program by utilizing 1L polyethylene glycol plus ascorbate (1L-PEGA) versus magnesium citrate plus picosulphate (SPMC), both administered in a split-dose regimen.

METHODS

We conducted a comparative, parallel, randomized, noninferiority, and low-intervention clinical trial, the study targeted individuals from a population colorectal cancer screening program aged 50-69 with a positive iFOBT result scheduled for a work-up colonoscopy in the morning. Participants were randomized to either 1L-PEGA or SPMC for bowel cleansing. Main outcome was ADR. Secondary outcomes were bowel preparation quality, individuals' safety, tolerability and satisfaction.

RESULTS

A total of 1,002 subjects were included, 501 in each group. There were no differences between groups with respect to pooled ADR (SPMC, 56.5% [52.1-60.8]; 1L-PEGA, 53.7% [49.3-58.0]; RR 0.95 [0.85-1.06]); therefore, SPMC demonstrated noninferiority in ADR compared to 1L-PEGA (difference, 2.8%; 2-sided 95% lower confidence limit (LCL), -3.4). In addition, there were no significant differences in mean lesions regardless of size and location between arms. Bowel preparation favored 1L-PEGA (96.2% vs. 89.2%; p<0.001) whereas SPMC exhibited significantly higher safety and tolerability, as evidenced by fewer non-serious treatment-emergent adverse events CONCLUSIONS: SPMC emerged as a noninferior laxative compared to 1L-PEGA concerning ADR. Despite the superior bowel preparation quality associated with 1L-PEGA, the safety, tolerability and overall satisfaction of participants were higher with SPMC. This trial was registered at ClinicalTrials.gov (EudraCT: 2019-003186-18) on March 18, 2019.

Development of Desmoid Tumors After Ileorectal Anastomosis Versus Ileal Pouch-Anal Anastomosis in Familial Adenomatous Polyposis

BACKGROUND & AIMS

Desmoid tumors (DT) are an important cause of morbidity and mortality in patients with familial adenomatous polyposis (FAP). DT development might be related to the type and approach of colectomy. We aimed to compare DT development after colectomy with ileorectal anastomosis (IRA) and proctocolectomy with ileal pouch-anal anastomosis (IPAA).

METHODS

We performed an international historical cohort study in patients with FAP who underwent IRA or IPAA between 1961 and 2020. The primary outcome was the incidence of abdominal DT (either mesenteric, retroperitoneal, or abdominal wall). Patients with a DT diagnosis before or at colectomy were excluded. Time to DT was considered censored at an eventual secondary proctectomy after IRA. We used multivariable Cox regression modelling to adjust for potential confounders.

RESULTS

We analyzed data from 852 patients: 514 after IRA and 338 after IPAA (median follow-up, 21 and 16 years, respectively). DTs were diagnosed in 64 IRA patients (12%) and 66 IPAA patients (20%). The cumulative DT incidence at 5 and 10 years was 7.5% and 9.3% after open IRA and 4.7% and 10.9% after laparoscopic IRA. These estimates were 13.6% and 15.4% after open IPAA and 8.4% and 10.0% after laparoscopic IPAA. The postoperative risk was significantly higher after IPAA (P < .01) in multivariable analysis, whereas approach did not significantly influence the risk.

CONCLUSIONS

The risk of developing an abdominal DT was found to be significantly higher after IPAA than after IRA. Postoperative DT risk should be taken into account when choosing between IRA and IPAA in FAP.

Colorectal polypectomy and endoscopic mucosal resection: European Society of Gastrointestinal Endoscopy (ESGE) Guideline - Update 2024

1:  ESGE recommends cold snare polypectomy (CSP), to include a clear margin of normal tissue (1-2 mm) surrounding the polyp, for the removal of diminutive polyps (≤ 5 mm).Strong recommendation, high quality of evidence. 2:  ESGE recommends against the use of cold biopsy forceps excision because of its high rate of incomplete resection.Strong recommendation, moderate quality of evidence. 3:  ESGE recommends CSP, to include a clear margin of normal tissue (1-2 mm) surrounding the polyp, for the removal of small polyps (6-9 mm).Strong recommendation, high quality of evidence. 4:  ESGE recommends hot snare polypectomy for the removal of nonpedunculated adenomatous polyps of 10-19 mm in size.Strong recommendation, high quality of evidence. 5:  ESGE recommends conventional (diathermy-based) endoscopic mucosal resection (EMR) for large (≥ 20 mm) nonpedunculated adenomatous polyps (LNPCPs).Strong recommendation, high quality of evidence. 6:  ESGE suggests that underwater EMR can be considered an alternative to conventional hot EMR for the treatment of adenomatous LNPCPs.Weak recommendation, moderate quality of evidence. 7:  Endoscopic submucosal dissection (ESD) may also be suggested as an alternative for removal of LNPCPs of ≥ 20 mm in selected cases and in high-volume centers.Weak recommendation, low quality evidence. 8:  ESGE recommends that, after piecemeal EMR of LNPCPs by hot snare, the resection margins should be treated by thermal ablation using snare-tip soft coagulation to prevent adenoma recurrence.Strong recommendation, high quality of evidence. 9:  ESGE recommends (piecemeal) cold snare polypectomy or cold EMR for SSLs of all sizes without suspected dysplasia.Strong recommendation, moderate quality of evidence. 10:  ESGE recommends prophylactic endoscopic clip closure of the mucosal defect after EMR of LNPCPs in the right colon to reduce to reduce the risk of delayed bleeding.Strong recommendation, high quality of evidence. 11:  ESGE recommends that en bloc resection techniques, such as en bloc EMR, ESD, endoscopic intermuscular dissection, endoscopic full-thickness resection, or surgery should be the techniques of choice in cases with suspected superficial invasive carcinoma, which otherwise cannot be removed en bloc by standard polypectomy or EMR.Strong recommendation, moderate quality of evidence.

Gender authorship in major American and European gastroenterology journals: the gap is still unfilled

BACKGROUND

The gender gap in the authorship of scientific research may affect career advancement. Our aim was to assess the potential gender gap in gastrointestinal (GI) journals.

METHODS

A systematic review was performed of the GI literature and ongoing research in the period 2020-2022. A total 10 GI journals and ongoing research on clinicaltrials.gov were selected for review. The gender gap in first and senior authorship was evaluated for each article and ongoing research project. Associations between the gender gap and possible predictors were measured and results are presented as odds ratios (ORs) with 95%CI.

RESULTS

The number of first female authors (FFAs) and senior female authors (SFAs) in published articles were 1408/4207 (33.5%) and 911/4207 (21.7%), respectively. There were 781/2654 (29.4%) female principal investigators (PI)s for the ongoing research. On comparison of non-endoscopic vs. endoscopic topics, the latter were associated with the gender gap (hepatology, OR 2.15 [95%CI 1.83-2.55]; inflammatory bowel disease, OR 2.12 [95%CI 1.60-2.45]; upper and lower GI, OR 1.31 [95%CI 1.18-1.73]); as well as the type of article (original article vs. editorial, OR 1.92 [95%CI 1.58-2.33]). The type of research was also associated with the gender gap (clinical vs. preclinical studies, OR 0.88 [95%CI 0.66-0.91]).

CONCLUSION

Our results demonstrated a correlation between the gender gap and the design and topic of the research. Future strategies for improving equity in career development in GI endoscopy should focus on closing the gender gap in equity of authorship.

Endoscopic management of patients with familial adenomatous polyposis after prophylactic colectomy or restorative proctocolectomy - systematic review of the literature

BACKGROUND

Patients with familial adenomatous polyposis (FAP) develop early colorectal adenomas and if left untreated, progression to cancer is an inevitable event. Prophylactic surgery does not prevent further development of cancer in the rectal remnant, rectal cuff in patients with ileal pouch anal anastomosis (IPAA) and even on the ileal mucosa of the pouch body. The aim of this review is to assess long-term rates of cancer and adenoma development in patients with FAP after prophylactic surgery and to summarise current recommendations for endoscopic management and surveillance of these patients.

MATERIALS AND METHODS

A systematic literature search of studies from January 1946 through to June 2023 was conducted using the PRISMA checklist. The electronic database PubMed was searched.

RESULTS

Fifty-four papers involving 5010 patients were reviewed. Cancer rate in the rectal remnant was 8.8-16.7% in the western population and 37% in the eastern population. The cumulative risk of cancer 30 years after surgery was 24%. Mortality due to cancer in the rectal remnant is 1.1-11.1% with a 5-year survival rate of 55%. The adenoma rate after primary IPAA was 9.4-85% with a cumulative risk of 85% 20 years after surgery and a cumulative risk of 12% for advanced adenomas 10 years after surgery. Cumulative risk for adenomas after ileorectal anastomosis (IRA) was 85% after 5 and 100% after 10 years. Adenomas developed more frequently after stapled (33.9-57%) compared to hand-sewn (0-33%) anastomosis. We identified reports of 45 cancers in patients after IPAA of which 30 were in the pouch body and 15 in the rectal cuff or at the anastomosis.

CONCLUSIONS

There was a significant incidence of cancer and adenomas in the rectal remnant and ileal pouch of FAP patients during the long-term follow-up. Regular endoscopic surveillance is recommended, not only in IRA patients, but also in pouch patients after proctocolectomy.

Linked-color imaging versus high definition white-light endoscopy for evaluation of post-polypectomy scars of nonpedunculated lesions: LCI-Scar study

BACKGROUND

Detection and treatment of recurrence after piecemeal endoscopic mucosal resection of nonpedunculated colorectal polyps are crucial for avoidance of post-colonoscopy cancer. Linked-color imaging (LCI) has demonstrated improved polyp detection but has never been assessed for evaluation of post-polypectomy scars. Our aim was to compare sensitivity and negative predictive value (NPV) between LCI and white-light endoscopy (WLE) for detection of post-polypectomy recurrence.

METHODS

Patients undergoing surveillance colonoscopy after resection of lesions ≥15 mm were included in this prospective, single-center, randomized, crossover study. Each post-polypectomy scar underwent two examinations, one with LCI and the other with WLE, performed by two blinded endoscopists. Blue-light imaging (BLI) was then applied. A diagnosis of recurrence with a level of confidence was made for each modality and histopathology was the gold standard.

RESULTS

129 patients with 173 scars were included. Baseline patient, lesion, and procedural characteristics were similar in both arms. Recurrence was detected in 56/173 (32.4%), with 27/56 (48.2%) adenomas and 29/56 (51.8%) serrated lesions. LCI had greater sensitivity (96.4% [95%CI 87.8%-99.5%]) versus WLE (89.3% [95%CI 78.1%-95.9%]) and greater NPV (98.1% [95%CI 93.4%-99.8%] versus 94.6% [95%CI 88.7%-98.0%]). Paired concordance between modalities was 96.0%. In discordant cases, LCI identified four true-positive cases not detected by WLE and reclassified one false-positive of WLE. WLE reclassified two false positives of LCI without any increase in recurrence detection.

CONCLUSIONS

LCI was highly accurate and had greater ability than WLE to rule out recurrence on post-polypectomy scars after resection of large polyps.

Training in basic gastrointestinal endoscopic procedures: a European Society of Gastrointestinal Endoscopy (ESGE) and European Society of Gastroenterology and Endoscopy Nurses and Associates (ESGENA) Position Statement

This ESGE Position Statement provides structured and evidence-based guidance on the essential requirements and processes involved in training in basic gastrointestinal (GI) endoscopic procedures. The document outlines definitions; competencies required, and means to their assessment and maintenance; the structure and requirements of training programs; patient safety and medicolegal issues. 1:  ESGE and ESGENA define basic endoscopic procedures as those procedures that are commonly indicated, generally accessible, and expected to be mastered (technically and cognitively) by the end of any core training program in gastrointestinal endoscopy. 2:  ESGE and ESGENA consider the following as basic endoscopic procedures: diagnostic upper and lower GI endoscopy, as well as a limited range of interventions such as: tissue acquisition via cold biopsy forceps, polypectomy for lesions ≤ 10 mm, hemostasis techniques, enteral feeding tube placement, foreign body retrieval, dilation of simple esophageal strictures, and India ink tattooing of lesion location. 3:  ESGE and ESGENA recommend that training in GI endoscopy should be subject to stringent formal requirements that ensure all ESGE key performance indicators (KPIs) are met. 4:  Training in basic endoscopic procedures is a complex process and includes the development and acquisition of cognitive, technical/motor, and integrative skills. Therefore, ESGE and ESGENA recommend the use of validated tools to track the development of skills and assess competence. 5:  ESGE and ESGENA recommend incorporating a multimodal approach to evaluating competence in basic GI endoscopic procedures, including procedural thresholds and the measurement and documentation of established ESGE KPIs. 7:  ESGE and ESGENA recommend the continuous monitoring of ESGE KPIs during GI endoscopy training to ensure the trainee's maintenance of competence. 9:  ESGE and ESGENA recommend that GI endoscopy training units fulfil the ESGE KPIs for endoscopy units and, furthermore, be capable of providing the dedicated personnel, infrastructure, and sufficient case volume required for successful training within a structured training program. 10:  ESGE and ESGENA recommend that trainers in basic GI endoscopic procedures should be endoscopists with formal educational training in the teaching of endoscopy, which allows them to successfully and safely teach trainees.

Lymph Node Molecular Analysis with OSNA Enables the Identification of pT1 CRC Patients at Risk of Recurrence: A Multicentre Study

Early-stage colorectal carcinoma (CRC)-pT1-is a therapeutic challenge and presents some histological features related to lymph node metastasis (LNM). A significant proportion of pT1 CRCs are treated surgically, resulting in a non-negligible surgical-associated mortality rate of 1.5-2%. Among these cases, approximately 6-16% exhibit LNM, but the impact on survival is unclear. Therefore, there is an unmet need to establish an objective and reliable lymph node (LN) staging method to optimise the therapeutic management of pT1 CRC patients and to avoid overtreating or undertreating them. In this multicentre study, 89 patients with pT1 CRC were included. All histological features associated with LNM were evaluated. LNs were assessed using two methods, One-Step Nucleic Acid Amplification (OSNA) and the conventional FFPE plus haematoxylin and eosin (H&E) staining. OSNA is an RT-PCR-based method for amplifying CK19 mRNA. Our aim was to assess the performance of OSNA and H&E in evaluating LNs to identify patients at risk of recurrence and to optimise their clinical management. We observed an 80.9% concordance in LN assessment using the two methods. In 9% of cases, LNs were found to be positive using H&E, and in 24.7% of cases, LNs were found to be positive using OSNA. The OSNA results are provided as the total tumour load (TTL), defined as the total tumour burden present in all the LNs of a surgical specimen. In CRC, a TTL ≥ 6000 CK19 m-RNA copies/µL is associated with poor prognosis. Three patients had TTL > 6000 copies/μL, which was associated with higher tumour budding. The discrepancies observed between the OSNA and H&E results were mostly attributed to tumour allocation bias. We concluded that LN assessment with OSNA enables the identification of pT1 CRC patients at some risk of recurrence and helps to optimise their clinical management.

Underwater cap-suction pseudopolyp formation for endoscopic mucosal resection: a simple technique for treating flat, appendiceal orifice or ileocecal valve colorectal lesions

BACKGROUND

We aimed to evaluate the safety and technical success of an easy-to-use technique that applies underwater cap suction pseudopolyp formation to facilitate the resection of flat lesions or those at the appendiceal orifice or ileocecal valve.

METHODS

We retrospectively analyzed a register of consecutive cap suction underwater endoscopic mucosal resection (CAP-UEMR) procedures performed at two centers between September 2020 and December 2021. Procedures were performed using a cone-shaped cap, extending 7 mm from the endoscope tip, to suction the lesion while submerged underwater, followed by underwater snare resection. Our primary end point was technical success, defined as macroscopic complete resection.

RESULTS

We treated 83 lesions (median size 20 mm; interquartile range [IQR] 15-30 mm) with CAP-UEMR: 64 depressed or flat lesions (18 previously manipulated, 9 with difficult access), 11 from the appendix, and 8 from the ileocecal valve. Technical success was 100 %. There were seven intraprocedural bleedings and two delayed bleedings, all managed endoscopically. No perforations or other complications occurred. Among the 64 lesions with follow-up colonoscopy, only one recurrence was detected, which was treated endoscopically.

CONCLUSIONS

CAP-UEMR was a safe and effective technique for removing nonpolypoid colorectal lesions, including those arising from the appendiceal orifice or ileocecal valve.

Cold snare polypectomy for duodenal adenomas in familial adenomatous polyposis: a prospective international cohort study

Background and study aims In patients with familial adenomatous polyposis (FAP), endoscopic resection of duodenal adenomas is commonly performed to prevent cancer and prevent or defer duodenal surgery. However, based on studies using different resection techniques, adverse events (AEs) of polypectomy in the duodenum can be significant. We hypothesized that cold snare polypectomy (CSP) is a safe technique for duodenal adenomas in FAP and evaluated its outcomes in our centers. Patients and methods We performed a prospective international cohort study including FAP patients who underwent CSP for one or more superficial non-ampullary duodenal adenomas of any size between 2020 and 2022. At that time, this technique was common practice in our centers for superficial duodenal adenomas. The primary outcome was the occurrence of intraprocedural and post-procedural AEs. Results In total, 133 CSPs were performed in 39 patients with FAP (1-18 per session). Median adenoma size was 10 mm (interquartile range 8-15 mm), ranging from 5 to 40 mm; 27 adenomas were ≥20 mm (20%). Of the 133 polypectomies, 109 (82%) were performed after submucosal injection. Sixty-one adenomas (46%) were resected en bloc and 72 (54%) piecemeal. Macroscopic radical resection was achieved for 129 polypectomies (97%). Deep mural injury type II occurred in three polyps (2%) with no delayed perforation after prophylactic clipping. There were no clinically significant bleeds, perforations or other post-procedural AEs. Histopathology showed low-grade dysplasia in all 133 adenomas. Conclusions CSP for (multiple) superficial non-ampullary duodenal adenomas in FAP seems feasible and safe. Long-term prospective research is needed to evaluate whether protocolized duodenal polypectomies prevent cancer and surgery.

pT1 colorectal cancer: A treatment dilemma

The implementation of population screening programs for colorectal cancer (CRC) has led to a considerable increase in the prevalence pT1-CRC originating on polyps amenable by local treatments. However, a high proportion of patients are referred for unnecessary oncological surgeries without a clear benefit in terms of survival. Selecting the appropriate endoscopic resection technique in the moment of diagnosis becomes crucial to provide the best treatment alternative to each individual polyp and patient. For this, it is imperative to increase the optical diagnostic skill for differentiating pT1-CRCs and decide the appropriate initial therapy. En bloc resection is crucial to obtain an adequate histological specimen that might allow organ preserving therapeutic management. In this review, we address key challenges in T1 CRC management, explore the efficacy and safety of the available diagnostic and therapeutic approaches, and shed light on upcoming advances in the field.

Informed consent for endoscopic procedures: European Society of Gastrointestinal Endoscopy (ESGE) Position Statement

All endoscopic procedures are invasive and carry risk. Accordingly, all endoscopists should involve the patient in the decision-making process about the most appropriate endoscopic procedure for that individual, in keeping with a patient's right to self-determination and autonomy. Recognition of this has led to detailed guidelines on informed consent for endoscopy in some countries, but in many no such guidance exists; this may lead to variations in care and exposure to risk of litigation. In this document, the European Society of Gastrointestinal Endoscopy (ESGE) sets out a series of statements that cover best practice in informed consent for endoscopy. These statements should be seen as a minimum standard of practice, but practitioners must be aware of and adhere to the law in their own country. 1:  Patients should give informed consent for all gastrointestinal endoscopic procedures for which they have capacity to do so. 2:  The healthcare professional seeking consent for an endoscopic procedure should ensure that the patient has the capacity to consent to that procedure. 3:  For patients who lack capacity, healthcare personnel should at all times try to engage with people close to the patient, such as family, friends, or caregivers, to achieve consensus on the appropriateness of performing the procedure. 4:  Where a patient lacks capacity to provide informed consent, the best interest decision should be clearly documented in the medical record. This should include information about the capacity assessment, reason(s) that the decision cannot be delayed for capacity recovery (or if recovery is not expected), who has been consulted, and where relevant the form of authority for the decision. 5:  There should be a systematic and transparent disclosure of the expected benefits and harms that may reasonably affect patient choice on whether or not to undergo any diagnostic or interventional endoscopic procedure. Information about possible alternatives, as well as the consequences of doing nothing, should also be provided when relevant. 6:  The information provided on the benefit and harms of an endoscopic procedure should be adapted to the procedure and patient-specific risk factors, and the preferences of the patient should be central to the consent process. 7:  The consent discussion should be undertaken by an individual who is familiar with the procedure and its risks, and is able to discuss these in the context of the individual patient. 8:  Patients should confirm consent to an endoscopic procedure in a private, unrushed, and non-coercive environment. 9:  If a patient requests that an endoscopic procedure be discontinued, the procedure should be paused and the patient's capacity for decision making assessed. If a competent patient continues to object to the procedure, or if a conclusive determination of capacity is not feasible, the examination should be terminated as soon as it is safe to do so. 10: Informed consent should be sufficiently detailed to cover all findings that can be reasonably anticipated during an endoscopic examination. The scope of this consent should not be expanded, nor a patient's implicit consent for additional interventions assumed, unless failure to proceed with such interventions would result in immediate and predictable harm to the patient.

High quality colonoscopy: using textbook process as a composite quality measure

BACKGROUND : High quality colonoscopy is fundamental to good patient outcomes. "Textbook outcome" has proven to be a feasible multidimensional measure for quality assurance between surgical centers. In this study, we sought to establish the "textbook process" (TP) as a new composite measure for the optimal colonoscopy process and assessed how frequently TP was attained in clinical practice and the variation in TP between endoscopists. METHODS : To reach consensus on the definition of TP, international expert endoscopists completed a modified Delphi consensus process. The achievement of TP was then applied to clinical practice. Prospectively collected data in two endoscopy services were retrospectively evaluated. Data on colonoscopies performed for symptoms or surveillance between 1 January 2018 and 1 August 2021 were analyzed. RESULTS : The Delphi consensus process was completed by 20 of 27 invited experts (74.1 %). TP was defined as a colonoscopy fulfilling the following items: explicit colonoscopy indication; successful cecal intubation; adequate bowel preparation; adequate withdrawal time; acceptable patient comfort score; provision of post-polypectomy surveillance recommendations in line with guidelines; and the absence of the use of reversal agents, early adverse events, readmission, and mortality. In the two endoscopy services studied, TP was achieved in 5962/8227 colonoscopies (72.5 %). Of 48 endoscopists performing colonoscopy, attainment of TP varied significantly, ranging per endoscopist from 41.0 % to 89.1 %. CONCLUSION : This study proposes a new composite measure for colonoscopy, namely "textbook process." TP gives a comprehensive summary of performance and demonstrates significant variation between endoscopists, illustrating the potential benefit of TP as a measure in future quality assessment programs.

Unraveling the impact of a germline heterozygous POLD1 frameshift variant in serrated polyposis syndrome

Serrated polyposis syndrome (SPS) is one of the most frequent polyposis syndromes characterized by an increased risk for developing colorectal cancer (CRC). Although SPS etiology has been mainly associated with environmental factors, germline predisposition to SPS could also be relevant for cases with familial aggregation or a family history of SPS/CRC. After whole-exome sequencing of 39 SPS patients from 16 families, we identified a heterozygous germline frameshift variant in the POLD1 gene (c.1941delG, p.(Lys648fs*46)) in a patient with SPS and CRC. Tumor presented an ultra-hypermutated phenotype and microsatellite instability. The POLD1 germline variant segregated in three additional SPS-affected family members. We attempted to create yeast and cellular models for this variant but were no viable. Alternatively, we generated patient-derived organoids (PDOs) from healthy rectal tissue of the index case, as well as from a control donor. Then, we challenged PDOs with a DNA-damaging agent to induce replication stress. No significant differences were observed in the DNA damage response between control and POLD1-Lys648fs PDOs, nor specific mutational signatures were observed. Our results do not support the pathogenicity of the analyzed POLD1 frameshift variant. One possible explanation is that haplosufficiency of the wild-type allele may be compensating for the absence of expression of the frameshift allele. Overall, future work is required to elucidate if functional consequences could be derived from POLD1 alterations different from missense variants in their proofreading domain. To our knowledge, our study presents the first organoid model for germline POLD1 variants and establishes the basis for its use as a model for disease in SPS, CRC and other malignancies.

Computer-aided classification of colorectal segments during colonoscopy: a deep learning approach based on images of a magnetic endoscopic positioning device

OBJECTIVE

Assessment of the anatomical colorectal segment of polyps during colonoscopy is important for treatment and follow-up strategies, but is largely operator dependent. This feasibility study aimed to assess whether, using images of a magnetic endoscope imaging (MEI) positioning device, a deep learning approach can be useful to objectively divide the colorectum into anatomical segments.

METHODS

Models based on the VGG-16 based convolutional neural network architecture were developed to classify the colorectum into anatomical segments. These models were pre-trained on ImageNet data and further trained using prospectively collected data of the POLAR study in which endoscopists were using MEI (3930 still images and 90,151 video frames). Five-fold cross validation with multiple runs was used to evaluate the overall diagnostic accuracies of the models for colorectal segment classification (divided into a 5-class and 2-class colorectal segment division). The colorectal segment assignment by endoscopists was used as the reference standard.

RESULTS

For the 5-class colorectal segment division, the best performing model correctly classified the colorectal segment in 753 of the 1196 polyps, corresponding to an overall accuracy of 63%, sensitivity of 63%, specificity of 89% and kappa of 0.47. For the 2-class colorectal segment division, 1112 of the 1196 polyps were correctly classified, corresponding to an accuracy of 93%, sensitivity of 93%, specificity of 90% and kappa of 0.82.

CONCLUSION

The diagnostic performance of a deep learning approach for colorectal segment classification based on images of a MEI device is yet suboptimal (clinicaltrials.gov: NCT03822390).

Familial component of early-onset colorectal cancer: opportunity for prevention

BACKGROUND

Individuals with a non-syndromic family history of colorectal cancer are known to have an increased risk. There is an opportunity to prevent early-onset colorectal cancer (age less than 50 years) (EOCRC) in this population. The aim was to explore the proportion of EOCRC that is preventable due to family history of colorectal cancer.

METHODS

This was a retrospective multicentre European study of patients with non-hereditary EOCRC. The impact of the European Society of Gastrointestinal Endoscopy (ESGE), U.S. Multi-Society Task Force (USMSTF), and National Comprehensive Cancer Network (NCCN) guidelines on prevention and early diagnosis was compared. Colorectal cancer was defined as potentially preventable if surveillance colonoscopy would have been performed at least 5 years before the age of diagnosis of colorectal cancer, and diagnosed early if colonoscopy was undertaken between 1 and 4 years before the diagnosis.

RESULTS

Some 903 patients with EOCRC were included. Criteria for familial colorectal cancer risk in ESGE, USMSTF, and NCCN guidelines were met in 6.3, 9.4, and 30.4 per cent of patients respectively. Based on ESGE, USMSTF, and NCCN guidelines, colorectal cancer could potentially have been prevented in 41, 55, and 30.3 per cent of patients, and diagnosed earlier in 11, 14, and 21.1 per cent respectively. In ESGE guidelines, if surveillance had started 10 years before the youngest relative, there would be a significant increase in prevention (41 versus 55 per cent; P = 0.010).

CONCLUSION

ESGE, USMSTF, and NCCN criteria for familial colorectal cancer were met in 6.3, 9.4, and 30.4 per cent of patients with EOCRC respectively. In these patients, early detection and/or prevention could be achieved in 52, 70, and 51.4 per cent respectively. Early and accurate identification of familial colorectal cancer risk and increase in the uptake of early colonoscopy are key to decreasing familial EOCRC.

In vivo computer-aided diagnosis of colorectal polyps using white light endoscopy

Background and study aims  Artificial intelligence is currently able to accurately predict the histology of colorectal polyps. However, systems developed to date use complex optical technologies and have not been tested in vivo. The objective of this study was to evaluate the efficacy of a new deep learning-based optical diagnosis system, ATENEA, in a real clinical setting using only high-definition white light endoscopy (WLE) and to compare its performance with endoscopists. Methods  ATENEA was prospectively tested in real life on consecutive polyps detected in colorectal cancer screening colonoscopies at Hospital Clínic. No images were discarded, and only WLE was used. The in vivo ATENEA's prediction (adenoma vs non-adenoma) was compared with the prediction of four staff endoscopists without specific training in optical diagnosis for the study purposes. Endoscopists were blind to the ATENEA output. Histology was the gold standard. Results  Ninety polyps (median size: 5 mm, range: 2-25) from 31 patients were included of which 69 (76.7 %) were adenomas. ATENEA correctly predicted the histology in 63 of 69 (91.3 %, 95 % CI: 82 %-97 %) adenomas and 12 of 21 (57.1 %, 95 % CI: 34 %-78 %) non-adenomas while endoscopists made correct predictions in 52 of 69 (75.4 %, 95 % CI: 60 %-85 %) and 20 of 21 (95.2 %, 95 % CI: 76 %-100 %), respectively. The global accuracy was 83.3 % (95 % CI: 74%-90 %) and 80 % (95 % CI: 70 %-88 %) for ATENEA and endoscopists, respectively. Conclusion  ATENEA can accurately be used for in vivo characterization of colorectal polyps, enabling the endoscopist to make direct decisions. ATENEA showed a global accuracy similar to that of endoscopists despite an unsatisfactory performance for non-adenomatous lesions.

Performance measures for colonoscopy in inflammatory bowel disease patients: European Society of Gastrointestinal Endoscopy (ESGE) Quality Improvement Initiative

The European Society of Gastrointestinal Endoscopy (ESGE) presents a short list of performance measures for colonoscopy in inflammatory bowel disease (IBD) patients. Current performance measures for colonoscopy mainly focus on detecting (pre)malignant lesions. However, these performance measures are not relevant for all colonoscopy indications in IBD patients. Therefore, our aim was to provide endoscopy services across Europe and other interested countries with a tool for quality monitoring and improvement in IBD colonoscopy. Eight key performance measures and one minor performance measure were recommended for measurement and evaluation in daily endoscopy practice.

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.

Differentially Deregulated MicroRNAs as Novel Biomarkers for Neoplastic Progression in Ulcerative Colitis

INTRODUCTION

Colorectal cancer (CRC) is a potentially life-threatening complication of long-standing ulcerative colitis (UC). MicroRNAs (miRNA) are epigenetic regulators that have been involved in the development of UC-associated CRC. However, their role as potential mucosal biomarkers of neoplastic progression has not been adequately studied.

METHODS

In this study, we analyzed the expression of 96 preselected miRNAs in human formalin-fixed and paraffin-embedded tissue of 52 case biopsies (20 normal mucosa, 20 dysplasia, and 12 UC-associated CRCs) and 50 control biopsies (10 normal mucosa, 21 sporadic adenomas, and 19 sporadic CRCs) by using Custom TaqMan Array Cards. For validation of deregulated miRNAs, we performed individual quantitative real-time polymerase chain reaction in an independent cohort of 50 cases (13 normal mucosa, 25 dysplasia, and 12 UC-associated CRCs) and 46 controls (7 normal mucosa, 19 sporadic adenomas, and 20 sporadic CRCs).

RESULTS

Sixty-four miRNAs were found to be differentially deregulated in the UC-associated CRC sequence. Eight of these miRNAs were chosen for further validation. We confirmed miR-31, -106a, and -135b to be significantly deregulated between normal mucosa and dysplasia, as well as across the UC-associated CRC sequence (all P < 0.01). Notably, these miRNAs also confirmed to have a significant differential expression compared with sporadic CRC (all P < 0.05).

DISCUSSION

UC-associated and sporadic CRCs have distinct miRNA expression patterns, and some miRNAs indicate early neoplastic progression.

Epigenome-Wide DNA Methylation Profiling of Normal Mucosa Reveals HLA-F Hypermethylation as a Biomarker Candidate for Serrated Polyposis Syndrome

Serrated polyposis syndrome (SPS) is associated with a high risk for colorectal cancer. Intense promoter hypermethylation is a frequent molecular finding in the serrated pathway and may be present in normal mucosa, predisposing to the formation of serrated lesions. To identify novel biomarkers for SPS, fresh-frozen samples of normal mucosa from 50 patients with SPS and 19 healthy individuals were analyzed by using the 850K BeadChip Technology (Infinium). Aberrant methylation levels were correlated with gene expression using a next-generation transcriptome profiling tool. Two validation steps were performed on independent cohorts: first, on formalin-fixed, paraffin-embedded tissue of the normal mucosa; and second, on 24 serrated lesions. The most frequently hypermethylated genes were HLA-F, SLFN12, HLA-DMA, and RARRES3; and the most frequently hypomethylated genes were PIWIL1 and ANK3 (Δβ = 10%; P < 0.05). Expression levels of HLA-F, SLFN12, and HLA-DMA were significantly different between SPS patients and healthy individuals and correlated well with the methylation status of the corresponding differentially methylated region (fold change, >20%; r > 0.55; P < 0.001). Significant hypermethylation of CpGs in the gene body of HLA-F was also found in serrated lesions (Δβ = 23%; false discovery rate = 0.01). Epigenome-wide methylation profiling has revealed numerous differentially methylated CpGs in normal mucosa from SPS patients. Significant hypermethylation of HLA-F is a novel biomarker candidate for SPS.