Evelien Dekker

Academisch Medisch Centrum Universiteit van Amsterdam, Amsterdamo, North Holland, Netherlands

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Publications (300)2425.12 Total impact

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    ABSTRACT: To develop standards for high quality in gastrointestinal (GI) endoscopy, the European Society of Gastrointestinal Endoscopy (ESGE) has established the ESGE Quality Improvement Committee. A prerequisite for quality assurance and improvement for all GI endoscopy procedures is state-of-the-art integrated digital reporting systems for standardized documentation of the procedures. The current paper describes the ESGE's viewpoints on the requirements for high-quality endoscopy reporting systems in GI endoscopy. Recommendations 1 Endoscopy reporting systems must be electronic. 2 Endoscopy reporting systems should be integrated into hospitals' patient record systems. 3 Endoscopy reporting systems should include patient identifiers to facilitate data linkage to other data sources. 4 Endoscopy reporting systems shall restrict the use of free-text entry to a minimum, and be based mainly on structured data entry. 5 Separate entry of data for quality or research purposes is discouraged. Automatic data transfer for quality and research purposes must be facilitated. 6 Double entry of data by the endoscopist or associate personnel is discouraged. Available data from outside sources (administrative or medical) must be made available automatically. 7 Endoscopy reporting systems shall facilitate the inclusion of information on histopathology of detected lesions, patient satisfaction, adverse events, and surveillance recommendations. 8 Endoscopy reporting systems must facilitate easy data retrieval at any time in a universally compatible format. 9 Endoscopy reporting systems must include data fields for key performance indicators as defined by quality improvement committees. 10 Endoscopy reporting systems must facilitate changes in indicators and data entry fields as required by professional organizations.
    No preview · Article · Feb 2016 · Endoscopy

  • No preview · Article · Jan 2016
  • Evelien Dekker · Silvia Sanduleanu
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    ABSTRACT: The interval colorectal cancer rate is a robust indicator of the quality and effectiveness of a screening programme, enabling the identification of unmet requirements and development of specific strategies to resolve them. A recent study demonstrated the use of interval cancer as an indicator to target quality improvement of colonoscopy in a screening programme.
    No preview · Article · Dec 2015 · Nature Reviews Gastroenterology &#38 Hepatology
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    ABSTRACT: Background and study aims: Evidence has accumulated that approximately 15 % to 30 % of colorectal cancers (CRC) arise from serrated polyps (SP). Population screening, therefore, should be designated to detect advanced SP, in addition to advanced adenomas and CRC. We aimed to evaluate whether CRC risk factors also act as risk factors for advanced SP. Patients and methods: Data were collected in the colonoscopy arm of a multicenter randomized trial comparing colonoscopy with CT-colonography for primary population screening. Information on risk factors was obtained by screening participants before colonoscopy with a validated risk questionnaire. Advanced SP were defined as SP ≥ 10 mm and/or with dysplasia. Endoscopists were instructed to resect all detected lesions. Odds ratios (OR) for the detection of advanced SP as most advanced lesion were calculated using multiple logistic regression analysis. Results: Of 6 600 invited participants, 1 426 underwent a colonoscopy and 1 236 also completed the questionnaire. In 40 participants an advanced SP was the most advanced lesion detected. Multivariate analysis demonstrated a strong association between current smoking and the presence of at least one advanced SP (OR 4.50; 95 % CI 2.23 - 8.89; P < 0.001). A significant association was also demonstrated for higher fiber intake (OR 1.36 per 20 gram intake; CI 1.07 - 1.73; P = 0.01). Other clinical CRC risk factors did not show a significant association with the presence of at least one advanced SP in the univariate analyses. Fecal haemoglobin levels were also not significantly associated with the presence of advanced SPs (OR 1.00 per 10 ng/mL CI 0.97 - 1.03, P = 0.99). Conclusions: Current smoking is a strong clinical risk factor for the presence of advanced SPs. As such, smoking status could contribute to risk stratification in targeted CRC population screening. Dutch Trial Register: NTR1829 (www.trialregister.nl).
    No preview · Article · Nov 2015
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    ABSTRACT: Objective: Serrated polyposis syndrome (SPS) is accompanied by an increased risk of colorectal cancer (CRC). Patients fulfilling the clinical criteria, as defined by the WHO, have a wide variation in CRC risk. We aimed to assess risk factors for CRC in a large cohort of patients with SPS and to evaluate the risk of CRC during surveillance. Design: In this retrospective cohort analysis, all patients with SPS from seven centres in the Netherlands and two in the UK were enrolled. WHO criteria were used to diagnose SPS. Patients who only fulfilled WHO criterion-2, with IBD and/or a known hereditary CRC syndrome were excluded. Results: In total, 434 patients with SPS were included for analysis; 127 (29.3%) were diagnosed with CRC. In a per-patient analysis ≥1 serrated polyp (SP) with dysplasia (OR 2.07; 95% CI 1.28 to 3.33), ≥1 advanced adenoma (OR 2.30; 95% CI 1.47 to 3.67) and the fulfilment of both WHO criteria 1 and 3 (OR 1.60; 95% CI 1.04 to 2.51) were associated with CRC, while a history of smoking was inversely associated with CRC (OR 0.36; 95% CI 0.23 to 0.56). Overall, 260 patients underwent surveillance after clearing of all relevant lesions, during which two patients were diagnosed with CRC, corresponding to 1.9 events/1000 person-years surveillance (95% CI 0.3 to 6.4). Conclusion: The presence of SPs containing dysplasia, advanced adenomas and/or combined WHO criteria 1 and 3 phenotype is associated with CRC in patients with SPS. Patients with a history of smoking show a lower risk of CRC, possibly due to a different pathogenesis of disease. The risk of developing CRC during surveillance is lower than previously reported in literature, which may reflect a more mature multicentre cohort with less selection bias.
    No preview · Article · Nov 2015 · Gut
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    ABSTRACT: BACKGROUND: We aimed to predict the long-term colorectal cancer incidence, mortality, and colonoscopy demand of the recently implemented Dutch colorectal cancer screening program. METHODS: The Adenoma and Serrated pathway to Colorectal Cancer model was set up to simulate the Dutch screening program consisting of biennial fecal immunochemical testing combined with the new Dutch surveillance guidelines, between 2014 and 2044. The impact of screening and surveillance was evaluated under three sets of natural history assumptions differing in the contribution of the serrated pathway to colorectal cancer incidence. In sensitivity analyses, other assumptions concerning the serrated pathway were varied. Model-predicted outcomes were yearly colorectal cancer incidence, mortality, and colonoscopy demand per year. RESULTS: Assuming an aging population, colorectal cancer incidence under 30 years of screening is predicted to decrease by 35% and 31% for a contribution of 0% and 30% of the serrated pathway to colorectal cancer, respectively. For colorectal cancer mortality, reductions are 47% and 45%. In 2044, 110,000 colonoscopies will be required annually assuming no contribution of the serrated pathway (27 per 1,000 individuals in the screening age range). Including the serrated pathway influences predicted screening effectiveness if serrated lesions are neither detected nor treated at colonoscopy, and/or if colorectal cancers arising from serrated lesions have substantially lower survival rates than those arising from adenomas. CONCLUSIONS: The Dutch screening program will markedly decrease colorectal cancer incidence and mortality but considerable colonoscopy resources will be required. IMPACT: Predictions of long-term screening effectiveness are preferably based on both pathways to colorectal cancer to transparently describe the impact of uncertainties regarding the serrated pathway on long-term predictions.
    Full-text · Article · Nov 2015 · Cancer Epidemiology Biomarkers & Prevention
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    ABSTRACT: Background: Research has shown that ethnic minority groups are less likely to participate in colorectal cancer (CRC) screening than the majority population and hence less likely to be diagnosed at an early stage when treatment is potentially more successful. Objective: To explore knowledge, attitudes and beliefs regarding CRC and CRC screening among ethnic minority groups in the Netherlands. Design: We conducted qualitative interviews with 30 first-generation immigrants born in Turkey, Morocco and Surinam. We based the topic guide on the health belief model. Framework analysis was used to analyse our data. Results: Although knowledge of CRC and CRC screening was limited, all respondents felt susceptible to CRC. CRC screening was perceived to mainly benefit those individuals with poor health and symptoms. Although most respondents had a positive attitude towards CRC screening, knowledge about its potential harms was limited and self-efficacy to participate was low. Adult children acted as important mediators in providing access to information. The language barrier and low literacy formed serious barriers to informed participation in CRC screening. Conclusion: To ensure that all eligible individuals, including ethnic minority groups, have equal opportunities to informed participation in screening, targeted communication strategies should be developed, such as oral and visual channels, and face-to-face communication in the mother tongue. This will help ethnic minority groups to make an informed decision about participation in CRC screening.
    Full-text · Article · Nov 2015 · Health expectations: an international journal of public participation in health care and health policy
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    ABSTRACT: Purpose: Surveillance CT colonography (CTC) is a viable option for 6-9 mm polyps at CTC screening for colorectal cancer. We established participation and diagnostic yield of surveillance and determined overall yield of CTC screening. Material and methods: In an invitational CTC screening trial 82 of 982 participants harboured 6-9 mm polyps as the largest lesion(s) for which surveillance CTC was advised. Only participants with one or more lesion(s) ≥6 mm at surveillance CTC were offered colonoscopy (OC); 13 had undergone preliminary OC. The surveillance CTC yield was defined as the number of participants with advanced neoplasia in the 82 surveillance participants, and was added to the primary screening yield. Results: Sixty-five of 82 participants were eligible for surveillance CTC of which 56 (86.2 %) participated. Advanced neoplasia was diagnosed in 15/56 participants (26.8 %) and 9/13 (69.2 %) with preliminary OC. Total surveillance yield was 24/82 (29.3 %). No carcinomas were detected. Adding surveillance results to initial screening CTC yield significantly increased the advanced neoplasia yield per 100 CTC participants (6.1 to 8.6; p < 0.001) and per 100 invitees (2.1 to 2.9; p < 0.001). Conclusion: Surveillance CTC for 6-9 mm polyps has a substantial yield of advanced adenomas and significantly increased the CTC yield in population screening. Key points: • The participation rate in surveillance CT colonography (CTC) is 86 %. • Advanced adenoma prevalence in a 6-9 mm CTC surveillance population is high. • Surveillance CTC significantly increases the yield of population screening by CTC. • Surveillance CTC for 6-9 mm polyps is a safe strategy. • Surveillance CTC is unlikely to yield new important extracolonic findings.
    Full-text · Article · Nov 2015 · European Radiology
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    ABSTRACT: Background and aims: The flexible endoscope is used as a platform for minimally invasive interventions. However, control of the conventional endoscope and multiple instruments is difficult. Robotic assistance could provide a solution and better control for a single operator. A novel platform should also enable interventions in areas that are currently difficult to reach. This study evaluates the safety and efficacy of a robotic platform that guides a conventional endoscope through the large bowel. Methods: In this feasibility study, adult patients scheduled for routine diagnostic colonoscopy were included. The endoscope was introduced using a robotic add-on to provide tip bending and air/water actuation. The endoscopist directly controlled the scope shaft. Upon cecal intubation, the add-on was detached and the procedure continued using conventional control. Primary evaluation parameters were the number of serious adverse events and the percentage of successful cecal intubations. Results: The procedure was performed in 22 consecutive patients who all gave informed consent. There were no serious adverse events. Cecal intubation was successful in 15 patients (68%) using the robotic add-on. Six cases were completed after conversion to conventional control: 3 cases were converted to pass sharp angulation in the flexures and 3 cases were converted after technical difficulties. One case was not successful with either technique due to severe diverticulosis. Conclusions: The robotic add-on steering module allows safe endoscope intubation to reach intervention sites throughout the large bowel. The next step is to clinically evaluate complementary instrument and shaft guiding modules in therapeutic procedures.
    No preview · Article · Nov 2015 · Gastrointestinal endoscopy
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    ABSTRACT: Objectives: Volumetric growth assessment has been proposed for predicting advanced histology at surveillance computed tomography (CT) colonography (CTC). We examined whether is it possible to predict which small (6-9 mm) polyps are likely to become advanced adenomas at surveillance by assessing volumetric growth. Methods: In an invitational population-based CTC screening trial, 93 participants were diagnosed with one or two 6-9 mm polyps as the largest lesion(s). They were offered a 3-year surveillance CTC. Participants in whom surveillance CTC showed lesion(s) of ≥6 mm were offered colonoscopy. Volumetric measurements were performed on index and surveillance CTC, and polyps were classified into growth categories according to ±30% volumetric change (>30% growth as progression, 30% growth to 30% decrease as stable, and >30% decrease as regression). Polyp growth was related to histopathology. Results: Between July 2012 and May 2014, 70 patients underwent surveillance CTC after a mean surveillance interval of 3.3 years (s.d. 0.3; range 3.0-4.6 years). In all, 33 (35%) of 95 polyps progressed, 36 (38%) remained stable, and 26 (27%) regressed, including an apparent resolution in 13 (14%) polyps. In 68 (83%) of the 82 polyps at surveillance, histopathology was obtained; 15 (47%) of 32 progressing polyps were advanced adenomas, 6 (21%) of 28 stable polyps, and none of the regressing polyps. Conclusions: The majority of 6-9 mm polyps will not progress to advanced neoplasia within 3 years. Those that do progress to advanced status can in particular be found among the lesions that increased in size on surveillance CTC.Am J Gastroenterol advance online publication, 20 October 2015; doi:10.1038/ajg.2015.340.
    Full-text · Article · Oct 2015 · The American Journal of Gastroenterology
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    ABSTRACT: Background: Specific genes, such as BCAT1 and IKZF1, are methylated with high frequency in colorectal cancer (CRC) tissue compared to normal colon tissue specimens. Such DNA may leak into blood and be present as cell-free circulating DNA. We have evaluated the accuracy of a novel blood test for these two markers across the spectrum of benign and neoplastic conditions encountered in the colon and rectum. Methods: Circulating DNA was extracted from plasma obtained from volunteers scheduled for colonoscopy for any reason, or for colonic surgery, at Australian and Dutch hospitals. The extracted DNA was bisulphite converted and analysed by methylation specific real-time quantitative PCR (qPCR). A specimen was deemed positive if one or more qPCR replicates were positive for either methylated BCAT1 or IKZF1 DNA. Sensitivity and specificity for CRC were estimated as the primary outcome measures. Results: Plasma samples were collected from 2105 enrolled volunteers (mean age 62 years, 54 % male), including 26 additional samples taken after surgical removal of cancers. The two-marker blood test was run successfully on 2127 samples. The test identified 85 of 129 CRC cases (sensitivity of 66 %, 95 % CI: 57-74). For CRC stages I-IV, respective positivity rates were 38 % (95 % CI: 21-58), 69 % (95 % CI: 53-82), 73 % (95 % CI: 56-85) and 94 % (95 % CI: 70-100). A positive trend was observed between positivity rate and degree of invasiveness. The colonic location of cancer did not influence assay positivity rates. Gender, age, smoking and family history were not significant predictors of marker positivity. Twelve methylation-positive cancer cases with paired pre- and post-surgery plasma showed reduction in methylation signal after surgery, with complete disappearance of signal in 10 subjects. Sensitivity for advanced adenoma (n = 338) was 6 % (95 % CI: 4-9). Specificity was 94 % (95 % CI: 92-95) in all 838 non-neoplastic pathology cases and 95 % (95 % CI: 92-97) in those with no colonic pathology detected (n = 450). Conclusions: The sensitivity for cancer of this two-marker blood test justifies prospective evaluation in a true screening population relative to a proven screening test. Given the high rate of marker disappearance after cancer resection, this blood test might also be useful to monitor tumour recurrence. Trial registration: ACTRN12611000318987 .
    Full-text · Article · Oct 2015 · BMC Cancer
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    ABSTRACT: Background and aims: Patients with longstanding colitis have an increased risk for developing CRC. Although the risk for ulcerative colitis is well established, for Crohn's disease data are contradictory. This study aims to determine the number Crohn's patients with dysplasia undergoing surveillance, and assess the diagnostic accuracy of chromoendoscopy (CE) combined with integrated confocal laser endomicroscopy (iCLE) for differentiating dysplastic versus non-dysplastic lesions. Methods: Patients with longstanding Crohn's colitis undergoing surveillance colonoscopy were included in this multicenter, prospective, cohort study. Surveillance was performed with CE and lesions were assessed with iCLE for differentiation. All lesions were removed and send in for pathology as reference standard. Results: Between 2010 and 2014, 61 Crohn's patients were included in 5 centers. Seventy-two lesions, of which 7 dysplastic, were detected in 6 patients (dysplasia detection rate: 9.8%), none included high-grade dysplasia or cancer. Combined CE with iCLE for differentiating neoplastic from non-neoplastic lesions, had an accuracy of 86.7% (95% CI, 78.1-95.3), sensitivity of 42.9% (95% CI, 11.8-79.8) and specificity of 92.4% (95% CI, 80.9-97.6). For CE alone this was 80.3% (95% CI, 70.7-89.9), 28.6% (95% CI, 5.1-69.7) and 86.4% (95% CI, 80.9-97.6). The study terminated early due to frequent failure of the endoscopic equipment. Conclusion: This study shows a low incidence of dysplastic lesions found during surveillance colonoscopy in longstanding extensive Crohn's colitis. The accuracy of both CE alone and in combination with iCLE was relatively good, although the sensitivity for both was poor. Due to frequent failure iCLE has limited applicability in daily practice as a surveillance strategy.
    No preview · Article · Sep 2015 · Gastrointestinal endoscopy
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    ABSTRACT: Implementation of nationwide screening programs aims to decrease the disease burden of colorectal cancer (CRC) in the general population. Globally, most population screening programs for CRC are performed by either fecal occult blood test, flexible sigmoidoscopy or colonoscopy. For screening programs with colonoscopy as primary method, only circumstantial evidence from observational studies is available to prove its effectiveness, suggesting that colonoscopy effectively reduces CRC incidence and mortality. Currently, large randomized trials are being conducted to corroborate these findings. Besides the direct effect of a screening program for CRC, its protective effect is further enhanced by enrolment of patients that underwent polypectomy in surveillance programs. However, despite CRC screening and surveillance colonoscopies, interval CRCs still occur. Those are predominantly located in the right-sided colon and potential explanations, besides unfavorable tumor characteristics, are preventable operator-dependent factors relating to the quality of the colonoscopy procedure. In an effort to reduce differences in endoscopists' performance and thereby the occurrence of interval CRCs, quality indicators of colonoscopy have been introduced. In addition, emerging advanced colonoscopy techniques might contribute to the improvement in polyp detection and removal. The meticulous inspection of the colonic mucosa not only results in the detection of advanced and relevant lesions, but also in the removal of many diminutive and small lesions leading to an increasing number of surveillance colonoscopies, known as the "high-detection paradox". More data on the cost-effectiveness of high quality colonoscopy as a primary screening method and surveillance programs with intervals based on optimal risk-stratification are eagerly awaited. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
    No preview · Article · Aug 2015 · Digestive Endoscopy
  • Evelien Dekker · Monique E van Leerdam

    No preview · Article · Aug 2015 · Gastrointestinal endoscopy
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    ABSTRACT: Objectives: Randomized trials demonstrated that chromoendoscopy is superior to white light endoscopy with random biopsy sampling (WLE) for the detection of dysplasia in patients with inflammatory bowel disease (IBD). Whether implementing chromoendoscopy can increase the detection of dysplasia in clinical practice is unknown. Methods: Patients with ulcerative colitis (UC) and Crohn's disease (CD) undergoing colonoscopic surveillance between January 2000 and November 2013 in three referral centers were identified using the patients' medical records. In recent years, the use of high-definition chromoendoscopy was adopted in all three centers using segmental pancolonic spraying of 0.1% methylene blue or 0.3% indigo carmine (chromoendoscopy group). Previously, surveillance was performed employing WLE with random biopsies every 10 cm (WLE group). The percentage of colonoscopies with dysplasia was compared between both groups. Results: A total of 440 colonoscopies in 401 patients were performed using chromoendoscopy and 1,802 colonoscopies in 772 patients using WLE. Except for a higher number of CD patients with extensive disease and more patients with a first-degree relative with colorectal cancer (CRC) in the chromoendoscopy group, the known risk factors for IBD-associated CRC were comparable between both groups. Dysplasia was detected during 48 surveillance procedures (11%) in the chromoendoscopy group as compared with 189 procedures (10%) in the WLE group (P=0.80). Targeted biopsies yielded 59 dysplastic lesions in the chromoendoscopy group, comparable to the 211 dysplastic lesions detected in the WLE group (P=0.30). Conclusions: Despite compelling evidence from randomized trials, implementation of chromoendoscopy for IBD surveillance did not increase dysplasia detection compared with WLE with targeted and random biopsies.
    No preview · Article · Jul 2015 · The American Journal of Gastroenterology
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    ABSTRACT: Background and study aims: Fecal immunochemical tests (FIT) are used to detect blood in feces, which might indicate the presence of colorectal neoplasia. The aim of this study was to investigate whether FIT results vary depending on the characteristics of colonic lesions. Patients and methods: This was a retrospective analysis of lesions detected in a cohort of asymptomatic individuals (aged 50 - 75 years) who were invited to participate in a FIT-based screening pilot in The Netherlands. The mean FIT result was compared across subgroups of individuals defined by histopathology of the most advanced lesion detected. In addition, the results were compared with data from a primary colonoscopy screening trial, in which participants also completed a FIT. Results: In three rounds of FIT-based screening, a total of 877 FIT-positive individuals underwent colonoscopy. Higher mean FIT results (hemoglobin [Hb]/g feces) were observed in individuals with carcinomas (199 μg Hb/g) and advanced adenomas (87 μg Hb/g) compared with participants with nonadvanced adenomas (50 μg Hb/g) or those with serrated lesions (46 μg Hb/g) (P < 0.001). In the primary colonoscopy trial, 1256 participants completed a FIT test and underwent colonoscopy. The number of participants with nonadvanced adenomas as the most advanced lesion was comparable between this group and the FIT-based screening group (20 % vs. 22 %). Conclusion: In FIT-based screening, the mean FIT results varied depending on the characteristics of the most advanced colonic lesion. The proportion of participants with a nonadvanced adenoma as the most advanced lesion was similar in the FIT-based screening group and in the primary colonoscopy screening group, suggesting that these lesions are coincidental findings rather than FIT-detected findings. www.trialregister.nl number NTR2755. © Georg Thieme Verlag KG Stuttgart · New York.
    No preview · Article · Jun 2015 · Endoscopy
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    ABSTRACT: Background and study aims: The most frequently cited prevalence for serrated polyposis syndrome (SPS) is 1 in every 3000 people screened, but this value is debated. Additionally, changes in 2010 in the World Health Organization (WHO) diagnostic criteria for SPS might affect reported prevalence. An updated estimate of SPS prevalence is necessary to predict the number of cases in screening programs. Patients and methods: A systematic literature search was conducted in the PubMed, EMBASE, and Web of Science databases up to February 2014. Studies reporting the prevalence of SPS, as defined by WHO criteria, in screening populations were selected. Results: Six studies reported prevalence of SPS in screening populations, varying from 0 to 0.66 %. The highest prevalences (0.34 % and 0.66 %) were seen in studies from screening programs with patients pre-selected by fecal blood test. Primary colonoscopy-based screening programs, that have the lowest risk of bias, reported SPS prevalences ranging from 0 to 0.09 %. Across studies, 56 patients were diagnosed with SPS of whom 3 presented with synchronous colorectal cancer at index endoscopy. Conclusion: The true prevalence of SPS is unclear because of the risk of bias across studies, but is likely to be below 0.09 % as derived from primary colonoscopy screening programs. The prevalence in pre-selected screening populations after positive fecal testing is higher, with reported values of 0.34 % and 0.66 %. Large and high quality primary colonoscopy screening studies, reporting SPS prevalence in adequately described populations, are necessary for better estimation of the true prevalence of SPS in average-risk patients. © Georg Thieme Verlag KG Stuttgart · New York.
    No preview · Article · Jun 2015 · Endoscopy
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    ABSTRACT: Conventional adenomas were traditionally thought to be the only precursors to colorectal cancer (CRC). Nowadays, also serrated polyps are acknowledged as precursor lesions for CRC, responsible for up to 30% of all CRCs and probably a larger percentage of interval CRCs after colonoscopy. In recent years, much research is being done to unravel the serrated neoplasia pathway. Endoscopic detection of serrated polyps is still a challenge for gastroenterologists, which is illustrated by large variations in detection rates of serrated polyps in the proximal colon. Clinical practice is further inhibited by poor optical differentiation of SSA/Ps from conventional adenomas and HPs and difficult delineation of those lesions, resulting in incomplete resection. The main focus of this review is to highlight recent advancements in endoscopic imaging techniques with regards to detection, differentiation and resection of serrated polyps.
    No preview · Article · Jun 2015 · Baillière&#x027 s Best Practice and Research in Clinical Gastroenterology
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    ABSTRACT: This study explored individuals' preferences for genetic testing for colorectal cancer (CRC) in a screening situation and their willingness to participate in genetic testing for Lynch syndrome, familial adenomatous polyposis (FAP), and familial colorectal cancer (FCC). For that purpose, 532 respondents aged 55-65 years completed a Discrete Choice Experiment. Using panel latent class models, the preferences for two screening situation characteristics (the probability of being genetically predisposed and the probability of developing CRC) and screening test characteristics (the frequency of preventive colonoscopies and CRC survival) were estimated. Based on these preferences, respondents' willingness to participate in the three screening initiatives was estimated. Lower-educated respondents and respondents who express serious anxiety and worries found colonoscopy frequency and the probability of developing CRC relatively more important and survival relatively less important compared with higher-educated respondents and respondents who express no anxiety and worries. These differences in preferences resulted in opposite preferences for participation in FCC and FAP screening. In conclusion, the general population is willing to participate in genetic screening for CRC. If individuals are suspected of genetic or familial CRC, they should at least be informed about their increased risk of being genetically predisposed and about the importance of participating in all preventive follow-up colonoscopies in order to maximize survival.European Journal of Human Genetics advance online publication, 3 June 2015; doi:10.1038/ejhg.2015.117.
    Full-text · Article · Jun 2015 · European journal of human genetics: EJHG
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    ABSTRACT: Introduction Colonoscopy is widely practised to reduce rates of colorectal cancer, although it does not confer absolute protection. The most hazardous part of colonoscopy is polypectomy, accounting for the majority of serious complications. It is unclear whether countries around the world have highlighted polypectomy as a specific skill that needs to be taught. The objective of the study was to assess both trainees’ and trainers’ experience of polypectomy training in countries around the world. Method Colonoscopy trainers from 19 countries worldwide (Figure 1)were asked to provide access to local trainers and trainees who would be invited to participate in a survey. An online survey was created asking about trainees’ experience of instruction and trainers’ experience of teaching polypectomy skills. Results Data were obtained from 610 colonoscopists- 348 (57.0%) trainers and 262 (43.0%) trainees. Most (79.6%) of the trainers surveyed were involved in polypectomy assessment weekly. 51.4% of those surveyed said that they used a specific framework when assessing polypectomy. 90.5% of trainees had a primary specialty of medical gastroenterology. The trainees had a breadth of colonoscopic experience, 31.7% having completed more than 500 colonoscopies and 38.2% fewer than 200 procedures. 51.1% stated that the principles of polypectomy had only been taught intermittently. Most (64.1%, 168 respondents) trainees had never been taught the principles of EMR. Only 53.1% of trainees had ever had their polypectomy technique formally assessed by any trainer. Of the 177 trainees who stated that they were competent at polypectomy, 70 (39.5%) had never had a formal evaluation of their polypectomy technique. Conclusion This study, the only in the literature, shows that polypectomy training is variable worldwide with low prevalence of formal competency assessment. There is a need to a) understand the learning curve for polypectomy, b) develop an international consensus defining optimal training methods and c) develop a framework of competency assessment. This should improve the safety of polypectomy and the effectiveness of colonoscopy in preventing colorectal cancer. Disclosure of interest None Declared. Reference
    No preview · Article · Jun 2015 · Gut

Publication Stats

5k Citations
2,425.12 Total Impact Points

Institutions

  • 2006-2015
    • Academisch Medisch Centrum Universiteit van Amsterdam
      • • Department of Gastroenterology and Hepatology
      • • Academic Medical Center
      Amsterdamo, North Holland, Netherlands
  • 2004-2015
    • University of Amsterdam
      • Department of Gastroenterology and Hepatology
      Amsterdamo, North Holland, Netherlands
  • 2012
    • Pontifical Catholic University of Chile
      CiudadSantiago, Santiago Metropolitan, Chile
    • Lyell McEwin Hospital
      Tarndarnya, South Australia, Australia
  • 2011
    • Technische Universität München
      München, Bavaria, Germany
  • 2009
    • Imperial College London
      Londinium, England, United Kingdom