Standardised training for endoscopic mucosal resection of large non-pedunculated colorectal polyps to reduce recurrence (*STAR-LNPCP study): a multicentre cluster randomised trial.

OBJECTIVE: Endoscopic mucosal resection (EMR) is the preferred treatment for non-invasive large (≥20 mm) non-pedunculated colorectal polyps (LNPCPs) but is associated with an early recurrence rate of up to 30%. We evaluated whether standardised EMR training could reduce recurrence rates in Dutch community hospitals. DESIGN: In this multicentre cluster randomised trial, 59 endoscopists from 30 hospitals were randomly assigned to the intervention group (e-learning and 2-day training including hands-on session) or control group. From April 2019 to August 2021, all consecutive EMR-treated LNPCPs were included. Primary endpoint was recurrence rate after 6 months. RESULTS: A total of 1412 LNPCPs were included; 699 in the intervention group and 713 in the control group (median size 30 mm vs 30 mm, 45% vs 52% size, morphology, site and access (SMSA) score IV, 64% vs 64% proximal location). Recurrence rates were lower in the intervention group compared with controls (13% vs 25%, OR 0.43; 95% CI 0.23 to 0.78; p=0.005) with similar complication rates (8% vs 9%, OR 0.93; 95% CI 0.64 to 1.36; p=0.720). Recurrences were more often unifocal in the intervention group (92% vs 76%; p=0.006). In sensitivity analysis, the benefit of the intervention on recurrence rate was only observed in the 20-40 mm LNPCPs (5% vs 20% in 20-29 mm, p=0.001; 10% vs 21% in 30-39 mm, p=0.013) but less evident in ≥40 mm LNPCPs (24% vs 31%; p=0.151). In a post hoc analysis, the training effect was maintained in the study group, while in the control group the recurrence rate remained high. CONCLUSION: A compact standardised EMR training for LNPCPs significantly reduced recurrences in community hospitals. This strongly argues for a national dedicated training programme for endoscopists performing EMR of ≥20 mm LNPCPs. Interestingly, in sensitivity analysis, this benefit was limited for LNPCPs ≥40 mm. TRIAL REGISTRATION NUMBER: NTR7477.

Thermal ablation of mucosal defect margins to prevent local recurrence of large colorectal polyps: a systematic review and meta-analysis.

Background and study aims Endoscopic mucosal resection of large non-pedunculated colorectal polyps is characterized by a high risk of recurrence. Thermal ablation of the mucosal defect margins may reduce recurrence in these lesions, but a systematic overview of the current evidence is lacking. Methods We searched PubMed, Embase and Cochrane until July 2021, for studies on thermal ablation of mucosal defect margins of large non-pedunculated colorectal polyps. Main goal of this meta-analysis was to identify pooled risk difference of recurrence between thermal ablation vs. no adjuvant treatment. Secondary goal was to identify pooled recurrence rate after snare tip soft coagulation (STSC) and argon plasma coagulation (APC). Results Ten studies on thermal ablation of mucosal defect margins were included, with three studies on argon plasma coagulation, six studies on snare tip soft coagulation and one study comparing both treatment modalities, representing a total of 316 APC cases and 1598 STSC cases. Overall pooled risk difference of recurrence was -0.17 (95 % confidence interval [CI] -0.22 to -0.12) as compared to no adjuvant treatment. Pooled risk difference was -0.16 (95 % CI -0.19 to -0.14) for STSC and -0.26 (95 % CI -0.80 to 0.28) for APC. Pooled recurrence rate was 4 % (95 % CI 2 % to 8 %) for STSC and 9 % (95 % CI 4 % to 19 %) for APC. Conclusions Thermal ablation of mucosal defect margins significantly reduces recurrence rate in large non-pedunculated colorectal lesions compared to no adjuvant treatment. While no evidence for superiority exists, STSC may be preferred over APC, because this method is the most evidence-based, and cost-effective modality.

Immediate coiling of a gastroduodenal arterial bleeding in a case of haemorrhagic shock without haematemesis, a case report.

Introduction: and importance: Upper gastrointestinal (GI) bleeding is common in the clinic. In combination with haemorrhagic shock, morbidity is high. Rapid diagnosis and treatment can save lives. With the introduction of precision imaging several treatment options are feasible. Up-to-date diagnosis and treatment requires expertise from interventional radiology, gastroenterology and surgery to form a dedicated intervention team. This is illustrated by a typical case. Case presentation: We report a 78-year-old otherwise healthy male with a severe diverticulum bleeding. He was initially diagnosed with acute pancreatitis. Approximately 60 minutes after CT scanning, he became haemodynamically instable. He also vomited coffee-like fluid but no clear blood or clots. A repeated CT scan showed active bleeding in the retroperitoneal space highly suspicious for a diverticular bleeding just outside the lumen of the duodenum. An acute multidisciplinary intervention team immediately decided not to perform endoscopy (according to the upper GI bleeding guidelines) but to extend the imaging procedure with digital subtraction angiography (DSA). By this time, active bleeding from a side branch of the gastroduodenal artery was noted and successfully coiled. Clinical discussion: Guidelines determine day-to-day management in clinical medicine. Still, there is an exception to every rule. The case presented here was typical of upper GI bleeding with haemodynamic instability and signs of shock, but without haematemesis. This combination indicated a bleeding from somewhere outside the lumen of the GI tract. Instead of endoscopy, the acute intervention team decided to perform CT angiography (CTa) with subsequent DSA. On imaging, the bleeding focus was immediately identified and treated by coiling. Conclusion: Performance of CTa immediately followed by DSA and no endoscopy was decided by an acute intervention team in a patient with upper GI bleeding and haemorrhagic shock. Swift coiling of the bleeding artery outside the GI tract lumen was successful. The team in charge relied on a hybrid multifunctional unit fully equipped to perform interventional radiologic as well as GI procedures.

Genetic Profiling of Colorectal Carcinomas of Patients with Primary Sclerosing Cholangitis and Inflammatory Bowel Disease.

BACKGROUND: Patients with primary sclerosing cholangitis (PSC) and inflammatory bowel disease (IBD) run a 10-fold increased risk of developing colorectal cancer (CRC) compared to patients with IBD only. The aim of this study was to perform an extensive screen of known carcinogenic genomic alterations in patients with PSC-IBD, and to investigate whether such changes occur already in nondysplastic mucosa. METHODS: Archival cancer tissue and nondysplastic mucosa from resection specimens of 19 patients with PSC-IBD-CRC were characterized, determining DNA copy-number variations, microsatellite instability (MSI), mutations on 48 cancer genes, and CpG island methylator phenotype (CIMP). Genetic profiles were compared with 2 published cohorts of IBD-associated CRC (IBD-CRC; n = 11) and sporadic CRC (s-CRC; n = 100). RESULTS: Patterns of chromosomal aberrations in PSC-IBD-CRC were similar to those observed in IBD-CRC and s-CRC, MSI occurred only once. Mutation frequencies were comparable between the groups, except for mutations in KRAS, which were less frequent in PSC-IBD-CRC (5%) versus IBD-CRC (38%) and s-CRC (31%; P = .034), and in APC, which were less frequent in PSC-IBD-CRC (5%) and IBD-CRC (0%) versus s-CRC (50%; P < .001). Cases of PSC-IBD-CRC were frequently CIMP positive (44%), at similar levels to cases of s-CRC (34%; P = .574) but less frequent than in cases with IBD-CRC (90%; P = .037). Similar copy number aberrations and mutations were present in matched cancers and adjacent mucosa in 5/15 and 7/11 patients, respectively. CONCLUSIONS: The excess risk of CRC in patients with PSC-IBD was not explained by copy number aberrations, mutations, MSI, nor CIMP status, in cancer tissue, nor in adjacent mucosa. These findings set the stage for further exome-wide and epigenetic studies.

The excessive risk of colorectal carcinoma (CRC) in patients with both primary sclerosing cholangitis and inflammatory bowel disease (IBD) was not explained by an extensive screen of copy number aberrations, mutations, microsatellite instability, and CpG island methylator phenotype status when compared with patients with IBD-CRC and sporadic CRC.

Electrolyte disturbances after bowel preparation for colonoscopy: Systematic review and meta-analysis.

BACKGROUND AND STUDY AIMS: We conducted a systematic review and meta-analysis of population-based studies to explore pooled prevalence and magnitude of electrolyte changes after bowel preparation for colonoscopy based on the most recent guidelines. PATIENTS AND METHODS: PubMed and Cochrane were queried for population-based studies examining changes in electrolyte values after bowel preparation, published by July 1, 2021. We report prevalences of serum hypokalemia, hyponatremia, hyperphosphatemia, and hypocalcemia after bowel preparation and changes in mean electrolyte values after vs. before bowel preparation using sodium phosphate (NaP) and polyethylene glycol (PEG). RESULTS: Thirteen studies met the inclusion criteria; 2386 unique patients were included. Overall, hypokalemia was found in 17.2% (95% CI 6.7, 30.9) in the NaP group vs. 4.8% (95% CI 0.27, 13.02) in the PEG group. The magnitude of potassium decrease after NaP bowel preparation was significantly increased compared to PEG (mean difference -0.38; 95% CI -0.49 to -0.27, P < 0.001). No study reported on major complications. CONCLUSIONS: Hypokalemia was found in 17.2% of patients after bowel preparation with NaP and in 4.8% of patients with PEG, a finding that is clinically relevant with respect to choosing the type of bowel preparation. The magnitude of the potassium decrease after NaP was significantly higher compared to PEG. These data provide the evidence that supports the recommendation of the European Society of Gastrointestinal Endoscopy against routine use of NaP for bowel preparation.

Molecular pathways in post-colonoscopy versus detected colorectal cancers: results from a nested case-control study.

BACKGROUND: Post-colonoscopy colorectal cancers (PCCRCs) pose challenges in clinical practice. PCCRCs occur due to a combination of procedural and biological causes. In a nested case-control study, we compared clinical and molecular features of PCCRCs and detected CRCs (DCRCs). METHODS: Whole-genome chromosomal copy number changes and mutation status of genes commonly affected in CRC were examined by low-coverage WGS and targeted sequencing, respectively. MSI and CIMP status was also determined. RESULTS: In total, 122 PCCRCs and 98 DCRCs with high-quality DNA were examined. PCCRCs were more often located proximally (P < 0.001), non-polypoid appearing (P = 0.004), early stage (P = 0.009) and poorly differentiated (P = 0.006). PCCRCs showed significantly less 18q loss (FDR < 0.2), compared to DCRCs. No significant differences in mutations were observed. PCCRCs were more commonly CIMP high (P = 0.014) and MSI (P = 0.029). After correction for tumour location, only less 18q loss remained significant (P = 0.005). CONCLUSION: Molecular features associated with the sessile serrated lesions (SSLs) and non-polypoid colorectal neoplasms (CRNs) are more commonly seen in PCCRCs than in DCRCs. These together with the clinical features observed support the hypothesis that SSLs and non-polypoid CRNs are contributors to the development of PCCRCs. The future focus should be directed at improving the detection and endoscopic removal of these non-polypoid CRN and SSLs. CLINICAL TRIAL REGISTRATION: NTR3093 in the Dutch trial register ( www.trialregister.nl ).

Evaluation of polypectomy quality indicators of large nonpedunculated colorectal polyps in a nonexpert, bowel cancer screening cohort.

BACKGROUND AND AIMS: With the introduction of the national bowel cancer screening program, the detection of sessile and flat colonic lesions ≥20 mm in size, defined as large nonpedunculated colorectal polyps (LNPCPs), has increased. The aim of this study was to examine the quality of endoscopic treatment of LNPCPs in the Dutch screening program. METHODS: This investigation comprised 2 related, but separate, substudies (1 with a cross-sectional design and 1 with a longitudinal design). The first examined prevalence and characteristics of LNPCPs in data from the national Dutch screening cohort from February 2014 until January 2017. The second, with screening data from 5 endoscopy units in the Southern part of the Netherlands from February 2014 until August 2015, examined performance on important quality indicators (technical and clinical successes, recurrence rate, adverse event rate, and surgery referral rate). All patients were part of the national Dutch screening cohort. RESULTS: In the national cohort, an LNPCP was detected in 8% of participants. Technical and clinical success decreased with increasing LNPCP size, from 93% and 96% in 20- to 29-mm lesions to 85% and 86% in 30- to 39-mm lesions and to 74% and 81% in ≥40-mm lesions (P < .001; P = .034). The cumulative recurrence rate at 12 months increased with LNPCP size, from 9% to 22% and 26% in the respective size groups (P = .095). The adverse event rate was 5%. The overall surgical referral rate for noninvasive LNPCPs was 7%. CONCLUSIONS: In this performance of 2 substudies, it was shown that quality parameters for endoscopic resection of large polyps in the Dutch screening cohort are not reached, especially in ≥30-mm polyps. Endoscopic resection of large polyps could benefit from additional training, quality monitoring, and centralization either within or between centers.

Examining the optimal cutoff values of HADS, PHQ-9 and GAD-7 as screening instruments for depression and anxiety in irritable bowel syndrome.

BACKGROUND: Self-rating scales are frequently used to screen for anxiety and depression in patients with irritable bowel syndrome (IBS). Different cutoff values are recommended in literature, and guidelines have suggested the use of other screening instruments over time. The aim of this study was to assess the correlation between the most commonly used psychological screening instruments for anxiety and depression in IBS and to compare custom cutoff scores for these instruments. METHODS: Irritable bowel syndrome patients (n = 192) completed several questionnaires including the Hospital Anxiety and Depression Scale (HADS, HADS-A and HADS-D subscale), Patient Health Questionnaire-9 (PHQ-9) and Generalized Anxiety Disorder-7 (GAD-7). Agreement at different cutoff points, for depressive and anxiety disorder, was assessed by use of the Gwet AC1 coefficient. KEY RESULTS: Hospital Anxiety and Depression Scale (HADS)-D and PHQ-9 scores, and HADS-A and GAD-7 scores showed high correlations (rs  = 0.735 and rs  = 0.805, respectively). For depressive disorder, a Gwet AC1 value of 0.829 was found when recommended cutoff points from literature were compared (PHQ-9 cutoff ≥10, HADS-D cutoff ≥8). For anxiety disorder, a Gwet AC1 value of 0.806 was found when recommended cutoff points from literature were compared (GAD-7 cutoff ≥10, HADS-A cutoff ≥8). Even higher agreements were found when higher HADS cutoff values were chosen, with impact on sensitivity and specificity. CONCLUSIONS & INFERENCES: Custom cutoff values deem the HADS subscales (HADS-D and HADS-A) concordant to PHQ-9 and GAD-7 scores. The choice of a cutoff value has substantial impact on sensitivity/specificity and is dependent on patient population, setting, and the purpose of use.

Metachronous neoplasms in patients with laterally spreading tumours during surveillance.

BACKGROUND: Laterally spreading tumours represent a major challenge for endoscopic detection and resection. OBJECTIVE: To examine synchronous and metachronous neoplasms in patients with laterally spreading tumours. METHODS: We prospectively collected colonoscopy and histopathology data from patients who underwent colonoscopy in our centre at up to 6 years' follow-up. Post-resection surveillance outcomes between laterally spreading tumours, flat colorectal neoplasms 10 mm or greater, and large polypoid colorectal neoplasms, polypoid colorectal neoplasms 10 mm or greater, were compared. RESULTS: Between 2008 and 2012, 8120 patients underwent colonoscopy for symptoms (84.6%), screening (6.7%) or surveillance (8.7%). At baseline, 151 patients had adenomatous laterally spreading tumours and 566 patients had adenomatous large polypoid colorectal neoplasms. Laterally spreading tumour patients had more synchronous colorectal neoplasms than large polypoid colorectal neoplasm patients (mean 3.34 vs. 2.34, p < 0.001). Laterally spreading tumour patients significantly more often developed metachronous colorectal neoplasms (71.6% vs. 54.2%, p = 0.0498) and colorectal neoplasms with high grade dysplasia/submucosal invasion than large polypoid colorectal neoplasm patients (36.4% vs. 15.8%, p < 0.001). After correction for age and gender, laterally spreading tumour patients were more likely than large polypoid colorectal neoplasm patients to develop a colorectal neoplasm with high grade dysplasia or submucosal invasion (hazard ratio 2.9, 95% confidence interval 1.8-4.6). The risk of metachronous colorectal cancer was not significantly different in laterally spreading tumours compared to large polypoid colorectal neoplasm patients. CONCLUSION: Patients with laterally spreading tumours developed more metachronous colorectal neoplasms with high grade dysplasia/submucosal invasion than large polypoid colorectal neoplasm patients. Based on these findings endoscopic treatment and surveillance recommendations for patients with laterally spreading tumours should be optimised.

Optical diagnosis of diminutive polyps in the Dutch Bowel Cancer Screening Program: Are we ready to start?

Background and study aims Implementation of optical diagnosis of diminutive polyps may potentially increase the efficacy and cost-effectiveness of colonoscopies. To adopt such strategy in clinical practice, the Preservation and Incorporation of Valuable endoscopic Innovations (PIVI) thresholds provide the basis to be met: ≥ 90 % negative predictive value (NPV) for diagnosis of adenomatous histology and ≥ 90 % agreement on surveillance intervals. We evaluated this within the Dutch Bowel Cancer Screening Program (BCSP). Patients and methods Endoscopic and histological data were collected from participants of the national bowel cancer screening program with an unfavorable fecal immunochemical test referred for colonoscopy between February 2014 and August 2015 at four endoscopy centers. The "resect and discard" scenario was studied, resecting diminutive polyps without histological evaluation. Agreement between optical diagnosis and histological diagnosis was measured for surveillance intervals according to Dutch, European and American post-polypectomy surveillance guideline. Results Fifteen certified endoscopists participated in this study and included 3028 diminutive polyps. In 2,330 patients both optical and histological diagnosis were available. Optical diagnosis of diminutive polyps showed NPV of 84 % (95 % CI 80-87) for adenomatous histology in the rectosigmoid. Applying the 'resect and discard' strategy resulted in 90.6 %, 91.2 %, 90.9 % agreement on surveillance intervals for the Dutch, European and American guideline respectively. Conclusion Our data representing current clinical practice in the Dutch BCSP practice on optical diagnosis of diminutive polyps showed that accuracy of predicting histology remains challenging, and risk of incorrect optical diagnosis is still significant. Therefore, it is too early to safely implement these strategies.

G-EYE colonoscopy is superior to standard colonoscopy for increasing adenoma detection rate: an international randomized controlled trial (with videos).

BACKGROUND AND AIMS: Colorectal cancer (CRC) is largely preventable with routine screening and surveillance colonoscopy; however, interval cancers arising from precancerous lesions missed by standard colonoscopy still occur. An increased adenoma detection rate (ADR) has been found to be inversely associated with interval cancers. The G-EYE device includes a reusable balloon integrated at the distal tip of a standard colonoscope, which flattens haustral folds, centralizes the colonoscope's optics, and reduces bowel slippage. The insufflated balloon also aims to enhance visualization of the colon during withdrawal, thereby increasing the ADR. METHODS: In this randomized, controlled, international, multicenter study (11 centers), patients (aged ≥50 years) referred to colonoscopy for screening, surveillance, or changes in bowel habits were randomized to undergo either balloon-assisted colonoscopy by using an insufflated balloon during withdrawal or standard high-definition colonoscopy. The primary endpoint was the ADR. RESULTS: One thousand patients were enrolled between May 2014 and September 2016 to undergo colonoscopy by experienced endoscopists; 803 were finally analyzed (standard colonoscopy n = 396; balloon-assisted colonoscopy n = 407). Baseline parameters were similar in both groups. Balloon-assisted colonoscopy provided a 48.0% ADR compared with 37.5% in the standard colonoscopy group (28% increase; P = .0027). Additionally, balloon-assisted colonoscopy provided for a significant increase in detection of advanced (P = .0033) flat adenomas (P < .0001) and sessile serrated adenomas/polyps (P = .0026). CONCLUSION: Balloon-assisted colonoscopy yielded a higher ADR and increased the detection of advanced, flat, and sessile serrated adenomas/polyps when compared with standard colonoscopy. Improved detection by the G-EYE device could impact the quality of CRC screening by reducing miss rates and consequently reducing interval cancer incidence. (Clinical trial registration number: NCT01917513.).

Update on the role of chromoendoscopy in colonoscopic surveillance of patients with Lynch syndrome.

(Virtual) chromoendoscopy (CE) improves the detection of small or flat colorectal polyps; however, the evidence in high-risk groups, such as patients of Lynch syndrome (LS), is low. Our aim was to identify and update the evidence for the recommendations regarding surveillance of LS patients, for which the current underlying evidence for use of (virtual) CE was explored. A systematic literature search in PubMed, EMBASE, and Cochrane library was conducted, for all studies comparing (virtual) CE with white-light endoscopy in LS patients. Studies are explained in detail, with special attention to study design, type of (virtual) CE, and timing of polypectomy. Eight studies (409 patients) were included. Five were nonrandomized back-to-back studies and three were randomized back-to-back studies (one parallel and two cross-over design). In six studies the polyps were directly removed, while in two studies polyps were removed only during the second caecal withdrawal. Five studies researched CE with indigo carmine and three studies investigated virtual CE. Due to the heterogeneity between studies, no statistical analysis could be performed. There was a large variety in study design, timing of polypectomy, different (virtual) CE techniques and the patients that were included. Based on current literature, no firm conclusions can be drawn with respect to the additional value of (virtual) CE in the surveillance of patients with LS. However, training of endoscopists in detection and removal of nonpolypoid colorectal neoplasms is crucial, as well as stricter adherence to LS surveillance guidelines in daily clinical practice. For future research, standardization in study designs is needed.

A Systematic Review and Meta-Analysis on Outcomes and Complications of Percutaneous Endoscopic Versus Radiologic Gastrostomy for Enteral Feeding.

BACKGROUND: The optimal technique for long-term enteral feeding has not yet been established. Both percutaneous endoscopic gastrostomy (PEG) and percutaneous radiologic gastrostomy (PRG) are widely used. Aim was to extensively review outcomes of PEG and PRG. MATERIALS AND METHODS: A systematic review using Medline, Embase, and Cochrane was performed, using standardized tools for assessing bias. Main outcomes were infectious and tube-related complications, procedure related and 30-day mortality. Pooled risk differences (RDs) with corresponding 95% confidence intervals (95% CIs) were calculated using random effects. Arcsine transformations were applied. RESULTS: In total, 344 studies were identified, of which 16 were included, reporting on 934 PEGs and 1093 PRGs. No differences were found for infectious complications [RD, 0.03 (-0.05 to 0.11)], procedure-related mortality [RD, 0.01 (-0.04 to 0.06)], or 30-day mortality [RD, 0.06 (-0.01 to 0.13)]. Tube-related complications were higher in PRG [RD, 0.16 (0.06-0.26)]. Subgroup analysis was performed for head and neck cancer (HNC) and motor neuron disease. In HNC, this revealed significantly lower tube-related complications and procedure-related mortality after PEG. In motor neuron disease, no differences were seen. The level of evidence appears sufficient considering the low degree of heterogeneity. CONCLUSIONS: No differences were found with regard to mortality or infectious complications. PEG showed lower risk of tube-related complications. Subgroup analysis revealed PEG to be favorable in HNC based on lower rates of procedure-related mortality and tube-related complications. Local experience and availability should be taken into account in the decision process.

Incidence and Classification of Postcolonoscopy Colorectal Cancers in Inflammatory Bowel Disease: A Dutch Population-Based Cohort Study.

BACKGROUND AND AIMS: Patients with inflammatory bowel disease [IBD] colitis are at increased risk for colorectal cancer [CRC]. We examined the proportion and most likely aetiology of potentially preventable postcolonoscopy CRCs [PCCRCs] in a population-based cohort. Furthermore, adherence to IBD surveillance guidelines was evaluated in both PCCRCs and the remainder of prevalent CRCs. METHODS: All IBD patients diagnosed from 1991 to 2011 in the South Limburg region of The Netherlands [i.e. IBDSL cohort] were included. CRC cases were cross-checked with the Dutch pathology database and cancer registry. PCCRCs were defined as cancers diagnosed within 6-60 months after a colonoscopy and were classified as attributable to 'inappropriate surveillance interval', 'inadequate bowel examination', 'incomplete resection', 'missed lesion' or 'newly developed cancer'. RESULTS: Twenty CRC cases were identified during 25,931 patient years of follow-up in 2,801 patients. The proportion of PCCRCs was 45.0%. Of these, 55.6% could be considered a 'missed lesion', while other possible aetiologies occurred only once. Considering both PCCRCs [n=9] and prevalent CRCs [n=11], ten were detected after publication of the surveillance guideline, but only three patients were enrolled. Moreover, 6 CRCs [30.0%] were detected before the recommended start of surveillance. CONCLUSIONS: In the IBDSL cohort, 45.0% of all CRCs were considered to be PCCRCs, mainly classified as missed lesions. Additionally, a large proportion of CRCs in our cohort were observed before a surveillance endoscopy was performed. Therefore, stringent adherence to IBD surveillance guidelines, improving endoscopy techniques and adjusting the surveillance program may lead to a decrease in CRC incidence.

Endoscopic subtypes of colorectal laterally spreading tumors (LSTs) and the risk of submucosal invasion: a meta-analysis.

BACKGROUND AND STUDY AIMS: Many studies have reported on laterally spreading tumors (LSTs), but systematic reviews of the data to determine their risk of containing submucosal invasion (SMI) are lacking. We systematically screened and analyzed the available literature to provide a more solid basis for evidence-based treatment. METHODS: We conducted a systematic search in PubMed, Embase, the Cochrane Library, and Scopus for published articles until July 2017. We estimated pooled prevalence or odds ratios (ORs) with 95 % confidence intervals (CIs), using random-effects models. We classified endoscopic subtypes into granular LST, which comprises the homogeneous and nodular mixed subtypes, and non-granular LST, which comprises the flat elevated and pseudodepressed subtypes. RESULTS: We identified 2949 studies, of which 48 were included. Overall, 8.5 % (95 %CI 6.5 % - 10.5 %) of LSTs contained SMI. The risk of SMI differed among the LST subtypes: 31.6 % in non-granular pseudodepressed LSTs (95 %CI 19.8 % - 43.4 %), 10.5 % in granular nodular mixed LSTs (95 %CI 5.9 % - 15.1 %), 4.9 % in non-granular flat elevated LSTs (95 %CI 2.1 % - 7.8 %), and 0.5 % in granular homogenous LSTs (95 %CI 0.1 % - 1.0 %). SMI was more common in distally rather than in proximally located LSTs (OR 2.50, 95 %CI 1.24 - 5.02). The proportion of SMI increased with lesion size (10 - 19 mm, 4.6 %; 20 - 29 mm, 9.2 %; ≥ 30 mm, 16.5 %). The pooled prevalence of patients with one or more LSTs in the general colonoscopy population was 0.8 % (95 %CI 0.6 % - 1.1 %). CONCLUSION: The majority of LSTs are non-invasive at the time of colonoscopic detection and can be treated with (piecemeal) endoscopic mucosal resection. Pretreatment diagnosis of endoscopic subtype, specifying areas of concern (nodule or depression), determines those LSTs at highest risk of containing SMI, where en bloc resection is the preferred therapy.

Optimizing post-polypectomy surveillance: A practical guide for the endoscopist.

Several gastrointestinal societies strongly recommend colonoscopy surveillance after endoscopic and surgical resection of colorectal neoplasms. Common denominators to these recommendations include: high-quality baseline colonoscopy before inclusion in a surveillance program; risk stratification based on clinicopathological profiles to guide surveillance intervals; and endoscopist responsibility for providing surveillance advice. Considerable variability also exists between guidelines (i.e. regarding risk classification and surveillance intervals). In this review, we examine key factors for quality of post-polypectomy surveillance practice, in particular bowel preparation, endoscopic findings at baseline examination and adherence to surveillance recommendations. Frequently asked questions by the practising endoscopist are addressed.