Surveillance For Colorectal Neoplasia Research Articles

Colorectal neoplasia surveillance in inflammatory bowel disease

Performing colorectal neoplasia surveillance in persons with inflammatory bowel disease (IBD) that is both clinically effective and cost effective is among the greatest challenges facing endoscopists who care for this population. While heightened colorectal cancer (CRC) risk has long been recognized among persons with IBD, this risk has been declining over time, with recent reports suggesting no more than a 1.5–2-fold higher risk compared to age and sex matched members of the general population. Nonetheless, given that CRC still occurs at a higher rate in this population, current surveillance strategies are inadequate for some persons. Conversely, 80–90% of persons with IBD had no neoplastic lesions identified during colonoscopy surveillance, suggesting that many persons with IBD are unnecessarily exposed to the risks of colonoscopy, with society bearing these excess costs.
 The purpose of colorectal neoplasia surveillance is to reduce the burden of CRC and CRC-related death in the IBD population. Societal guidelines recommend initiating colorectal neoplasia screening with colonoscopy in all persons with colorectal IBD involving at least the rectosigmoid (or at least 1/3 of the colorectum if accompanied by discontinuous inflammation) at 8–10 years following disease diagnosis and continuing lifelong surveillance every 1–5 years. Major factors influencing surveillance frequency include historical disease severity, extent of colorectal inflammation, chronic post-inflammatory changes, family history of CRC, history of colorectal neoplasm, primary sclerosing cholangitis, prior colonoscopy findings, and adequacy of prior surveillance. All guidelines further recommend targeted sampling or resection of suspicious visible abnormalities, and some societies continue to recommend extensive non-targeted biopsies to detect “invisible” neoplasia, particularly if other adjunctive optical modalities, such as dye-spray chromoendoscopy (DCE) or virtual chromoendoscopy (VCE), are not performed, or if the mucosa is poorly visualized, such as in areas of significant inflammation, post-inflammatory polyposis, or poor bowel preparation. Most societies now advocate for DCE or VCE as primary screening tools for IBD neoplasia surveillance or, at a minimum, as alternative modalities to traditional white light colonoscopy with non-targeted biopsies where resources and expertise exists.
 However, there are no prospective studies demonstrating a reduction in the incidence of CRC or of death from CRC with current surveillance strategies in persons with IBD. Furthermore, observations from large retrospective studies are also conflicting. A Cochrane analysis of 3 studies in persons with UC did not find a significant mortality benefit for current surveillance strategies. Considering that IBD afflicts many persons at a young age, is rising in prevalence in Canada and globally, and requires intensive lifelong surveillance , the amount of endoscopy resources directed toward IBD surveillance is potentially enormous. Increasing demands on colonoscopy resources from expansion of population-based CRC screening programs and an aging population are likely to challenge the ability to continue to provide intensive surveillance to all persons with IBD. Optimizing delivery of limited colonoscopy resources will thus be essential to maintain effective CRC prevention programs in this population.
 Current standards for neoplasia surveillance in IBD have been recently updated. Shah and Itzkowitz authored a comprehensive review that includes epidemiology, pathogenesis, and management of colorectal neoplasia, along with a chart that compares surveillance recommendations put forward by multiple societies. The present review will highlight new evidence influencing neoplasia surveillance and provide practical approaches for surveillance and management of neoplastic lesions in the IBD population.

Accuracy of a faecal immunochemical test in patients under colonoscopy surveillance of colorectal adenoma and cancer.

Surveillance of colorectal neoplasia place great strain on colonoscopy resources, and faecal immunochemical tests (FIT) are under-investigated for this purpose. The aim of this study was to report the outcome of FIT among patients scheduled for post-polypectomy and post-resection colorectal cancer (CRC) surveillance. Patients scheduled for colonoscopy surveillance at five endoscopy units in mid-Sweden in 2016-2020 were eligible. They provided a faecal sample from 2 separate days, which were analysed by iFOBT QuikRead go® (Aidian Oy). Both the colonoscopies, and the FIT analyses were conducted by staff blinded to the other. Out of 216 included patients, 157 (73%) underwent both a complete colonoscopy and had at least one FIT analysed prior to the examination. The indication for surveillance was previous adenoma in 69 (44%) and post-resection CRC in 88 (56%) patients. Two (1%) in the CRC surveillance group were diagnosed with a metachronous CRC, whereas 49 (56%) patients in the CRC surveillance, and 17 (25%) in the adenoma group had no pathology identified at colonscopy (P < 0.001). The proportion of patients diagnosed with adenomas requiring surveillance according to European Society of Gastrointestinal Society (ESGE) guidelines 2020 was 6 (7%) in the post-CRC resection versus 7 (10%) in the adenoma surveillance group (P = 0.4). Based on one FIT and at cut-off 10 µg Hb/g, sensitivity for CRC was 100%, specificity 83% (95% confidence interval [CI]: 77-89), Positive Predictive Value (PPV) 7% (-2 to 16) and Negative Predictive Value (NPV) 100%. All patients with an adenoma requiring surveillance had a FIT below this cut-off. Adding a second FIT decreased the specificity. Larger studies to evaluate the accuracy and consequences of using FIT for surveillance of colorectal neoplasia are needed. FIT may be more interesting for post-resection CRC surveillance than follow-up of adenoma.

Surveillance for Colorectal Neoplasia in Inflammatory Bowel Disease: When to Stop.

Patients with chronic ulcerative and Crohn's colitis are at increased risk for colorectal neoplasia(CRN [dysplasia and cancer]) compared to the general population. Risk factors for CRN include extent of colitis, cumulative inflammatory burden, family history of colorectal cancer, and primary sclerosing cholangitis. Best practices to prevent CRN include control of colonic inflammation, high quality surveillance colonoscopy with or without enhanced imaging techniques, resection of visible dysplasia if possible, and colectomy in patients with unresectable dysplasia, invisible multifocal low grade dysplasia, or invisible high grade dysplasia. Cessation of dysplasia surveillance is individualized and should involve shared decision making based on factors including but not limited to chronologic age, frailty, co-morbid conditions, life expectancy, results of prior surveillance exams, and risk factors for CRN.

Systematic review: non‐endoscopic surveillance for colorectal neoplasia in individuals with Lynch syndrome

SummaryBackgroundIndividuals with Lynch syndrome are at high risk for colorectal cancer (CRC). Regular colonoscopies have proven to decrease CRC incidence and mortality. However, colonoscopy is burdensome and interval CRCs still occur. Hence, an accurate, less‐invasive screening method that guides the timing of colonoscopy would be of important value.AimTo outline the performance of non‐endoscopic screening modalities for Lynch‐associated CRC and adenomas.MethodsSystematic literature search in MEDLINE and EMBASE to identify studies investigating imaging techniques and biomarkers for detection of CRC and adenomas in Lynch syndrome. The QUADAS‐2 tool was used for the quality assessment of included studies.ResultsSeven of 1332 screened articles fulfilled the inclusion criteria. Two studies evaluated either CT colonography or MR colonography; both techniques were unable to detect CRC and (advanced) adenomas <10 mm. The other five studies evaluated plasma methylated‐SEPTIN9, faecal immunochemical test (FIT), faecal tumour DNA markers (BAT‐26, hMLH1, p53, D9S171, APC, D9S162, IFNA and DCC) and faecal microbiome as screening modalities. Sensitivity for CRC varied from 33% (BAT‐26) to 70% (methylated‐SEPTIN9) to 91% (hMLH1). High specificity (94–100%) for CRC and/or adenomas was observed for methylated‐SEPTIN9, FIT and BAT‐26. Desulfovibrio was enriched in the stool of patients having adenomas. However, all these studies were characterised by small populations, high/unclear risk of bias and/or low prevalence of adenomas.ConclusionsImaging techniques are unsuitable for colon surveillance in Lynch syndrome, whereas biomarkers are understudied. Having outlined biomarker research in Lynch‐associated and sporadic CRC/adenomas, we believe that these non‐invasive markers may hold potential (whether or not combined) for this population. As they could be of great value, (pre‐)clinical studies in this field should be prioritised.

Reappraising Risk Factors for Inflammatory Bowel Disease-associated Neoplasia: Implications for Colonoscopic Surveillance in IBD.

One of the most feared complications of inflammatory bowel disease [IBD]-associated colitis is colorectal cancer. When considering the substantial increase in the prevalence of IBD, without any anticipated decline, coupled with decreasing colectomy rates for dysplasia and expanding medical options for effectively controlling inflammation, it is predicted that the pool of people living with-and ageing with-colonic IBD, who are recommended to undergo lifelong colonoscopic surveillance for colorectal neoplasia, will strain existing resources and challenge the sustainability of current guideline-based surveillance recommendations. At the same time, we are missing the opportunity for early detection in a group that is overlooked as high-risk, as a substantial proportion of colorectal cancers are being diagnosed in individuals with colonic IBD who have disease duration shorter than when guidelines recommend surveillance initiation. Here, we reappraise: 1] inflammation as a dynamic risk factor that considers patients' cumulative course; 2] time of screening initiation that is not based primarily on absolute disease duration; and 3] surveillance intervals as an iterative determination based on individual patient factors and consecutive colonoscopic findings. This Viewpoint supports a paradigm shift that will ideally result in a more effective and higher-value colorectal cancer prevention approach in IBD.

Association Between Indefinite Dysplasia and Advanced Neoplasia in Patients With Inflammatory Bowel Diseases Undergoing Surveillance

Background and aimsLittle is known about the clinical significance of indefinite dysplasia (IND) in patients with inflammatory bowel diseases (IBD) undergoing colonoscopic surveillance for colorectal neoplasia.MethodsWe conducted a retrospective cohort analysis of 492 patients with colonic IBD for 8 or more years or concomitant primary sclerosing cholangitis, with no history of advanced colorectal neoplasia (high-grade dysplasia or colorectal cancer) or colectomy, undergoing colorectal neoplasia surveillance at tertiary IBD referral center from 2001 through 2017. Subjects received consistent histopathologic grading of dysplasia. We collected data on time to development of (advanced) colorectal neoplasia or colectomy using Kaplan Meier methods. We identified factors independently associated with (advanced) colorectal neoplasia with multivariable Cox regression analysis.ResultsAfter 2149 person-years of follow-up, 53 patients (10.8%) received a diagnosis of IND without prior or synchronous low-grade dysplasia (LGD). Compared to patients without dysplasia, patients with IND had a significantly higher risk of advanced colorectal neoplasia (adjusted hazard ratio, 6.85; 95% CI, 1.78–26.4) and colorectal neoplasia (adjusted hazard ratio, 3.25; 95% CI, 1.50–7.05), but not colectomy (P=.78). Compared to IND, LGD was associated with a significantly higher risk of advanced colorectal neoplasia (P=.05). Following a diagnosis of no dysplasia, IND only, or LGD, the incidence rates of advanced colorectal neoplasia were 0.4% per patient-year, 3.1% per patient-year, and 8.4% per patient-year, respectively.ConclusionsIn a retrospective analysis of patients with IBD undergoing colorectal neoplasia surveillance with consistent histopathologic grading of dysplasia, IND was independently associated with a significant increase in risk of advanced colorectal neoplasia. These findings require validation and if confirmed, a reappraisal of the colorectal neoplasia surveillance guidelines.

Selected complications of colonoscopy – an anaesthetist’s point of view

Colonoscopy is a commonly performed procedure for the diagnosis and treatment of a wide range of conditions and symptoms, as well as for the screening and surveillance of colorectal neoplasia. Serious complications, such as bleeding and perforation, are reported in patients undergoing colonoscopy, especially during polypectomy. Bleeding is the most common complication of colonic polypectomy. It can occur immediately following polypectomy or be delayed from hours to up to days. Acute post-polypectomy haemorrhage is usually immediately apparent and amenable to endoscopic therapy. Nonendoscopic treatment modalities include angiographic embolization and surgery. Acute massive bleeding (internal bleeding/haemorrhage) into the lower gastrointestinal tract may cause hypovolaemia, which decreases cardiac output and tissue oxygen supply, which may require emergency surgery. Although colonic perforation is a rare complication, it is associated with a high rate of morbidity and mortality. This unpleasant complication could result in surgical intervention, stoma formation, intra-abdominal sepsis, prolonged hospital stay, and even death. An extra-intestinal structure identified during endoscopic examination is the most common clinical feature of colonic perforation. The management of patients with colonic perforation should be individualized based on patients’ clinical status and underlying diseases, the nature of perforation, and concomitant colorectal pathologies. Patients with both acute massive bleeding and lower gastrointestinal perforation may need emergency laparotomy, which requires perioperative cooperation of an endoscopist, a surgeon and an anaesthetist.

Effect of I-scan Electronic Chromoendoscopy on Detection of Adenomas During Colonoscopy

I-scan is an electronic chromoendoscopy technology that improves resolution of epithelial and mucosal surfaces and vessels. We performed a randomized controlled trial to compare detection of adenomas by i-scan vs standard high-definition white-light (HDWL) colonoscopy. From February 1 through December 31, 2017, 740 outpatients (50-75 years old) undergoing screening and surveillance for colorectal neoplasia were randomly assigned to groups that received colonoscopies with i-scan 1 (surface and contrast enhancement) or HDWL. When lesions and polyps were detected, endoscopists could switch between i-scan 1 and HDWL imaging to confirm their finding; polyps were collected and analyzed by histology. The primary outcome was adenoma detection rate (ADR, proportion of subjects with at least 1 adenoma of any size); secondary outcomes included detection of sessile serrated polyps and neoplasias, along with location, size, and morphology of polyps. We performed intent to treat and per-protocol analyses (on 357 patients evaluated by i-scan and 358 evaluated by HDWL colonoscopy) to assess the primary and secondary outcomes. There were no differences in baseline characteristics between the groups. In the intent to treat analysis, the ADR was significantly higher in the i-scan 1 group (47.2%) than in the HDWL colonoscopy group (37.7%) (P = .01). In the per-protocol analysis, the ADR in the i-scan 1 group (47.6%) was also significantly higher than in the HDWL group (37.2%) (P = .005), but this effect was not consistent among all endoscopists. There was no difference between groups in detection of sessile serrated polyps. However, the rate of neoplasia detection was significantly higher in the i-scan 1 group (56.4%) than in the than the HDWL group (46.1%) (P=.005). In secondary analyses, the increase in ADR was associated with improved detection of diminutive flat adenomas in the right colon. In a prospective randomized trial, higher proportions of patients with adenomas were identified in a group that underwent colonoscopy with i-scan 1 than in a group evaluated by HDWL colonoscopy. This effect was mainly due to improved detection of diminutive, flat right sided adenomas. I-scan 1 technology may benefit some endoscopists. ClinicalTrials.gov no: NCT02811419.

Performance of quantitative immunochemical test for fecal hemoglobin for surveillance of colorectal neoplasia after polypectomy in clinical practice

SummaryAimsWe examined the yield of immunochemical test for fecal hemoglobin (FIT) for the post‐polypectomy individuals in a colorectal cancer screening program.MethodsWe enrolled 50‐75 years average‐risk individuals who attended a biennial FIT‐based colorectal cancer screening program from March 2010 to December 2011 (index round) and from January 2012 to December 2013 (repeated round). Colonoscopy was recommended to the participants with an FIT ≧ 30 μg Hb/g feces.Participants identified with adenomas and removed by polypectomy in the index round were defined as surveillance group (Sur‐G). Participants with an FIT &lt; 30 μg Hb/g feces in the index round or identified as non‐neoplastic findings of the indexed colonoscopy were defined as repeated screening group (Rsc‐G). We compared key quality indicators for FIT and colonoscopy between Sur‐G and Rsc‐G according to the findings of the repeated round. A p &lt; 0.05 determined by chi‐square test was defined as significant.ResultsThere were 222 post‐polypectomy surveillance (Sur‐G) and 7311 repeated screening individuals (Rsc‐G) enrolled for analysis. The FIT positivity rate, colonoscopy compliance rate and colorectal neoplasia (CRN) detection rate were 504 of 7311 (6.9%) vs. 46 of 222 (20.7%) (p &lt; 0.001); 381 of 504 (75.6%) vs. 44 of 46 (95.7%) (p &lt; 0.001) and 207 of 504 (41.1%) vs. 32 of 46 (69.6%) (p &lt; 0.001) for Rsc‐G and Sur‐G respectively. The FIT positivity rate, colonoscopy compliance rate and CRN detection rate were significantly higher in the Sur‐G.ConclusionsOur results suggest individuals after polypectomy still had high risk of CRN. Biennial FIT may play a role for post‐polypectomy surveillance. Subsequent prospective study is necessary to evaluate the effectiveness of FIT for post‐polypectomy surveillance.Copyright © 2017, The Gastroenterological Society of Taiwan, The Digestive Endoscopy Society of Taiwan and Taiwan Association for the Study of the Liver.

Transparency ethics in practice: Revisiting financial conflicts of interest disclosure forms in clinical practice guidelines.

BackgroundAuthors of clinical practice guidelines (CPGs) disclose financial conflicts of interest (FCOIs) to promote transparency ethics. Typically, they do so on standard declaration forms containing generic open-ended questions on FCOIs. Yet, the literature is scant on the format and effect of alternative disclosure forms. Does supplementing a standard form with subsequent detailed disclosure forms tailored to the context of the CPG improve the yield or accuracy of FCOIs declarations?MethodsFor an international CPG in gastroenterology on the endoscopic surveillance for colorectal neoplasia in inflammatory bowel disease, we compared the use of a standard FCOIs disclosure form with a contextual FCOIs disclosure form that detailed commercial relations related to the CPG topic. This included manufacturers of endoscopes, endoscopy equipment and accessories. Participants completed the generic form early, and the supplementary contextual form six months later. We then compared the FCOI disclosures obtained.Findings26 participants provided FCOIs disclosures using both disclosure forms. We found discrepancies regarding (1) the disclosure of FCOIs (presence/absence), and (2) the listing of financial entities. While the number of participants who disclosed a FCOI remained the same (30.8%) using the two forms, disclosures were not from the same individuals: two additional participants disclosed a FCOI, whereas two participants withdrew previous disclosures. Among those who reported a FCOI in either form, we noted inconsistencies in disclosures for 70% of the participants. This included changes in FCOIs disclosure status or modifications of "their commercial relations".DiscussionAccurate reporting of FCOIs advances the transparency and ethical integrity of CPGs. Our experience suggests that a contextual FCOIs disclosure form tailored to content of the CPG with narrow, detailed questions provides supplementary, more complete FCOIs declarations than generic forms alone. The finding raises challenges on how forms are best written and formatted, optimally timed, and more effectively processed with sensitivity to professional behaviour, so as to heighten transparency.

Stool DNA Analysis is Cost-Effective for Colorectal Cancer Surveillance in Patients With Ulcerative Colitis.

Patients with chronic ulcerative colitis are at increased risk for colorectal neoplasia (CRN). Surveillance by white-light endoscopy (WLE) or chromoendoscopy may reduce risk of CRN, but these strategies are underused. Analysis of DNA from stool samples (sDNA) can detect CRN with high levels of sensitivity, but it is not clear if this approach is cost-effective. We simulated these strategies for CRN detection to determine which approach is most cost-effective. We adapted a previously published Markov model to simulate the clinical course of chronic ulcerative colitis, the incidence of cancer or dysplasia, and costs and benefits of care with 4 surveillance strategies: (1) analysis of sDNA and diagnostic chromoendoscopy for patients with positive results, (2) analysis of sDNA with diagnostic WLE for patients with positive results, (3) chromoendoscopy with targeted collection of biopsies, or (4) WLE with random collection of biopsies. Costs were based on 2014 Medicare reimbursement. The primary outcome was the incremental cost-effectiveness ratio (incremental cost/incremental difference in quality-adjusted life-years) compared with no surveillance and a willingness-to-pay threshold of $50,000. All strategies fell below the willingness-to-pay threshold at 2-year intervals. Incremental cost-effectiveness ratios were $16,362 per quality-adjusted life-year for sDNA analysis with diagnostic chromoendoscopy; $18,643 per quality-adjusted life-year for sDNA analysis with diagnostic WLE; $23,830 per quality-adjusted life-year for chromoendoscopy alone; and $27,907 per quality-adjusted life-year for WLE alone. In sensitivity analyses, sDNA analysis with diagnostic chromoendoscopy was more cost-effective than chromoendoscopy alone, up to a cost of $1135 per sDNA test. sDNA analysis remained cost-effective at all rates of compliance; when combined with diagnostic chromoendoscopy, this approach was preferred over chromoendoscopy alone, when the specificity of the sDNA test for CRN was >65%. Based on a Markov model, surveillance for CRN is cost-effective for patients with chronic ulcerative colitis. Analysis of sDNA with chromoendoscopies for patients with positive results was more cost-effective than chromoendoscopy or WLE alone.

Use of Macrophage Inhibitory Cytokine-1 as a Biomarker in Screening and Surveillance of Colorectal Neoplasia.

Use of Macrophage Inhibitory Cytokine-1 as a Biomarker in Screening and Surveillance of Colorectal Neoplasia

Sa1021 Cost-Effectiveness Analysis of Stool DNA or Colonoscopy for Colorectal Neoplasia Surveillance in Patients With Ulcerative Colitis

Sa1021 Cost-Effectiveness Analysis of Stool DNA or Colonoscopy for Colorectal Neoplasia Surveillance in Patients With Ulcerative Colitis

Current status of capsule endoscopy through a whole digestive tract.

More than a decade has passed since small-bowel capsule endoscopy (CE) was first reported. Small-bowel CE is a non-invasive tool that allows visualization of the entire small-intestinal mucosa and facilitates detection of small-intestinal abnormalities. Several studies have shown benefit of small-bowel CE for certain disorders. Because it is non-invasive, CE has been applied to other organs including the esophagus, stomach, and colon. The main indications for esophageal CE (ECE) are screening for gastroesophageal reflux disease/Barrett's esophagus, and esophageal varices. However, the clinical benefit of ECE is unconfirmed. Magnetically guided CE (MGCE) was developed to visualize the gastric mucosa. MGCE is a new concept with room for improvement of capsule navigation and the preparation protocol. Recently, two new small-bowel CE tools were released. First-generation colon CE (CCE-1) has moderate sensitivity and specificity compared with colonoscopy for colorectal neoplasia surveillance. To obtain higher accuracy, a second-generation CCE (CCE-2) was developed with a high sensitivity for detecting clinically relevant polypoid lesions. A possible application of CCE is for inflammatory bowel disease. In the near future, CE may include diagnostic and therapeutic functions such as magnifying endoscopy systems, targeted biopsy forceps, and drug delivery systems.

Colon cancer surveillance in inflammatory bowel disease: unclear gain but no psychological pain?

Surveillance for colorectal neoplasia in inflammatory bowel disease (IBD) is widely practised despite a lack of convincing mortality reduction. The psychological impact of this approach is largely unexplored. To examine psychological well-being among IBD subjects undergoing colonoscopic surveillance for colorectal cancer (CRC). A cross-sectional study was performed by interrogating an IBD database for subjects currently enrolled in colonoscopic surveillance programmes. Identified surveillance subjects were age- and gender-matched with IBD control subjects not meeting surveillance criteria. Subjects were mailed a questionnaire including demographic details, the Short Form 36 (SF-36) survey to assess quality of life, the Spielberger State-Trait Personality Inventory, the Multidimensional Health Locus of Control, and a Risk Perception Questionnaire. One hundred and thirty-nine of 286 (49%) subjects responded, 53% male, 46% Crohn disease. Fifty-six per cent respondents were in the surveillance group. Surveillance subjects were older (55.4 vs 51.1 years; P = .048) with longer disease duration, but otherwise had comparable demographics with controls. Overall, quality of life was not significantly different between cohorts (mean SF-36 63.82 vs 65.48; P = 0.70). Groups did not differ on any locus of control classification (P = 0.52), nor was there any difference between mean scores on 'state' subscales of the Spielberger State-Trait Personality Inventory: anxiety (P = 0.91), curiosity (P = 0.12), anger (P = 0.81) or depression (P = 0.70). Both groups grossly overestimated their perceived lifetime risk of CRC at 50%, with no difference between surveillance and control subjects (P = 1.0). Enrolment in colonoscopic colon cancer surveillance does not appear to impair psychological well-being in individuals with IBD despite longer disease duration. IBD patients overestimate their risk of CRC.

Colorectal Neoplasia Surveillance in Patients with Inflammatory Bowel Disease and Primary Sclerosing Cholangitis: An Economic Evaluation

Colorectal Neoplasia Surveillance in Patients with Inflammatory Bowel Disease and Primary Sclerosing Cholangitis: An Economic Evaluation

Risk factors associated with colorectal flat adenoma detection

Colorectal flat adenomas have been associated with a higher risk of colorectal malignancy. We describe demographic characteristics and endoscopic findings in patients with colorectal flat adenomas. In total, 1934 consecutive patients undergoing colonoscopy were prospectively included. Polyp shape was classified according to the Japanese classification. Chromoendoscopy was applied whenever a flat lesion was suspected. Indications for colonoscopy, demographic data, and characteristics of neoplastic lesions were recorded. Patients were classified as follows: group 1, no adenomas (n=1250); group 2, only protruding adenomas (n=427); group 3, protruding and flat adenomas (n=118); and group 4, only flat adenomas (n=139). Approximately one in every 10 patients (13.2%) had flat adenomas. Among them, concomitant protruding adenomas were identified in approximately half of the cases. In multivariate analysis, age older than 50 years [odds ratio (OR)=1.62; 95% confidence interval (CI)=1.08-2.43, P=0.02], protruding adenomas (OR=2.17; 95% CI=1.65-2.87, P<0.001), follow-up colonoscopy for polyps or cancer (OR=2.22; 95% CI=1.59-3.10, P<0.001), screening colonoscopy (OR=1.60, 95% CI=1.15-2.22, P=0.005), and specifically trained endoscopist (OR=2.02, 95% CI=1.53-2.68, P<0.001) were associated independently with flat adenoma detection. Flat adenomas have specific demographic factors that might help to improve detection. Particularly, age older than 50 years, colorectal neoplasia surveillance, and the presence of protruding adenomas should alert endoscopists to the possible presence of these lesions. Trained endoscopists may offer a greater chance of detecting these lesions.

A prospective intervention study of colonoscopy reporting among patients screened or surveilled for colorectal neoplasia.

The impact of modifying electronic colonoscopy reporting software for improving adherence to guidelines regarding quality standards documentation remains poorly characterized. Consecutive colonoscopy reports of patients undergoing screening or surveillance for colorectal neoplasia were reviewed. Following a pre-intervention quality audit conducted in 2009, some modifications were made to the reporting software (Endoworks, Olympus Corporation, USA), including changes to field navigation, drop-down menus and visual cues, to optimize all compulsory items identified by existing guidelines in the report-generating template. Results from both audits were compared. Independent validation of 10% of all data was completed. In 250 patient reports (mean [± SD] age 61.7±10.2 years, 51.2% female, February to May 2011) of five endoscopists (mean 11.6±7.8 years in practice), procedural indication was always present, as was informed consent. Seventy-six per cent of patients had undergone previous colonoscopy, 41% provided a previous colonoscopy date, with details on past polyp removal in 42.9%. Most procedural indicators were recorded (examination date 100%, medications given 100%, difficulty level 96.4%, preparation quality 100%). All reports noted extent of visualization (cecal intubation in 97.6%, photo documentation in 96.8%). Total procedural time was recorded in 8.2% and withdrawal time in 44%. Polyps were reported in 112 patients (44.8%), with polyp size (5.01±4.42 mm) reported in 95.5%, morphology in 88.4% and anatomical location in all. The method of polyp removal was missing in 2.7% of reports. Significant improvements were noted in the documentation of withdrawal and total time, cecal landmarks, type of bowel preparation, completeness of removal, morphology and method of polyp removal, and photo documentation compared with the 2009 audit. These results illustrate the value of targeted modifications to an electronic colonoscopic reporting system in significantly enhancing the quality of reporting.

Optical Enhancements in Diagnosis and Surveillance of Colorectal Neoplasia

The influx of new endoscopic technologies produces continuous evolution in diagnostic modalities, especially in colorectal cancer screening. New technologies seek not only to improve the detection of flat and difficult-to-visualize lesions, but also to more precisely differentiate between neoplastic and non-neoplastic lesions. The oldest technology, chromoendoscopy, has been shown to improve neoplasia detection in high-risk subjects, but it is not widely accepted due to its cumbersome nature. Newer technologies such as narrow-band imaging provide digital chromoendoscopy, yielding improved lesion detection and characterization with less inconvenience. Other technologies such as confocal endomicroscopy allow endoscopists to make in vivo histologic diagnoses of suspicious areas. Collectively, these emerging technologies may change the way that colonoscopy is performed.

Screening and surveillance for colorectal neoplasia: uncertainties of colonoscopic management

Over the past decade the use of screening and surveillance modalities has been associated with a small but significant decrease in the incidence of colorectal cancer and an increase in curability of lesions that are found. Although consensus-based international guidelines have stressed the variety of possible diagnostic options that can serve this purpose, in many countries colonoscopy withremoval of all polyps has become the test of choice. The evidence-base for this choice is largely derivative rather than direct and prospective, and many uncertainties remain in its use as a primary screening modality. This review examines our current guidelines relative to risk stratifying the populations offered the test; the onset, interval, and discontinuation of testing; and the important role of operator variability in outcome.