UK key performance indicators and quality assurance standards for colonoscopy

Practical gastrointestinal investigation of iron deficiency anaemia

About 10% of oesophagogastroduodenoscopies (OGDs) and colonoscopies are done for investigation of iron deficiency anemia (IDA) . Much of the existing guidance on investigation of IDA predates CRC screening, which has driven significant improvements in colonoscopy quality and completion rates, as well as a reduction in Helicobacter pylori prevalence and increase in PPI usage, and therefore probably needs re-consideration. New investigations, e.g. CT colonography, enteroscopy and capsule endoscopy have also been introduced. Areas covered: This review updates the approach to practical investigation of IDA. Medline was searched using the terms iron deficiency AND anemia AND/OR gastroscopy, colonoscopy, capsule and enteroscopy, together with review of recent relevant published abstracts on the topic. Expert commentary: Gastrointestinal pathology is now a more common cause of IDA than upper GI causes, reflecting better colonoscopy accuracy and completion rates as well as changing disease patterns, and carcinomas are more likely cause IDA than benign adenomas. Increasing use of antiplatelet and anticoagulants is driving greater presentation of IDA. Capsule endoscopy, enteroscopy and CT colonography are increasingly used. Fecal occult blood testing may be a useful simple screening method in the frail, as a negative test can avoid the need for invasive tests.

Post-imaging colorectal cancer or interval cancer rates after CT colonography: a systematic review and meta-analysis

BACKGROUND

CT colonography is highly sensitive for colorectal cancer, but interval or post-imaging colorectal cancer rates (diagnosis of cancer after initial negative CT colonography) are unknown, as are their underlying causes. We did a systematic review and meta-analysis of post-CT colonography and post-imaging colorectal cancer rates and causes to address this gap in understanding.

METHODS

We systematically searched MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials. We included randomised, cohort, cross-sectional, or case-control studies published between Jan 1, 1994, and Feb 28, 2017, using CT colonography done according to international consensus standards with the aim of detecting cancer or polyps, and reporting post-imaging colorectal cancer rates or sufficient data to allow their calculation. We excluded studies in which all CT colonographies were done because of incomplete colonoscopy or if CT colonography was done with knowledge of colonoscopy findings. We contacted authors of component studies for additional data where necessary for retrospective CT colonography image review and causes for each post-imaging colorectal cancer. Two independent reviewers extracted data from the study reports. Our primary outcome was prevalence of post-imaging colorectal cancer 36 months after CT colonography. We used random-effects meta-analysis to estimate pooled post-imaging colorectal cancer rates, expressed using the total number of cancers and total number of CT colonographies as denominators, and per 1000 person-years. This study is registered with PROSPERO, number CRD42016042437.

FINDINGS

2977 articles were screened and 12 studies were eligible for analysis. These studies reported data for 19 867 patients (aged 18-96 years; of 11 590 with sex data available, 6532 [56%] were female) between March, 2002, and May, 2015. At a mean of 34 months' follow-up (range 3-128·4 months), CT colonography detected 643 colorectal cancers. 29 post-imaging colorectal cancers were subsequently diagnosed. The pooled post-imaging colorectal cancer rate was 4·42 (95% CI 3·03-6·42) per 100 cancers detected, corresponding to 1·61 (1·11-2·33) post-imaging colorectal cancers per 1000 CT colonographies or 0·64 (0·44-0·92) post-imaging colorectal cancers per 1000 person-years. Heterogeneity was low (I²=0%). 17 (61%) of 28 post-imaging colorectal cancers were attributable to perceptual error and were visible in retrospect.

INTERPRETATION

CT colonography does not lead to an excess of post-test cancers relative to colonoscopy within 3-5 years, and the low 5-year post-imaging colorectal cancer rate confirms that the recommended screening interval of 5 years is safe. Since most post-imaging colorectal cancers arise from perceptual errors, radiologist training and quality assurance could help to reduce post-imaging colorectal cancer rates.

FUNDING

St Mark's Hospital Foundation and the UK National Institute for Health Research via the UCL/UCLH Biomedical Research Centre.

Screening colonoscopy and risk of adverse events among individuals undergoing fecal immunochemical testing in a population-based program: A nested case-control study

Background

Screening by means of biennial fecal occult blood test has provided a reduction in overall colorectal cancer mortality. Notwithstanding, we should not underestimate the harms that it can produce.

Aim

The aim of this article is to identify the independent risk factors of complications after a screening colonoscopy.

Methods

A six-year, nested case-control study was conducted. Mortality/complications within 30 days after colonoscopy were registered and its predictors identified through logistic regression.

Results

After 39,254 colonoscopies, the complication rate was 1.0%. Independent predictors were sex (OR 1.68 for men; CI 95% 1.18-2.39), ASA physical status classification system (OR 1.73 for ASA II-III; CI 95% 1.53-3.69), history of abdominal surgery (OR 2.37; CI 95% 1.72-4.08), diverticulosis (OR 2.89; CI 95% 1.94-4.30), inadequate cleansing (OR 29.35; CI 95% 6.52-132.17), detection of advanced neoplasia (AN) (OR 4.92; CI 95% 3.29-7.36), detection of stage I adenocarcinoma (OR 9.44; CI 95% 4.46-20.0), polyps in right colon OR 2.27 CI 95% 1.38-3.74) and complex polypectomy (OR 2.00; CI 95% 1.25-3.20). The logistic model explained 82% of the complications (CI 95% 0.798-0.854, p < 0.001).

Conclusions

Colonoscopy, with or without removal of a lesion, is an invasive procedure with a non-deniable risk of major complications. Factors like inadequate cleansing or detection of AN are determinants. Therefore, it is vital to know which aspects predict their appearance to implement countermeasures.

Can technology increase adenoma detection rate?

Colorectal cancer is the third most common cancer worldwide and the second most common cause of cancer-related death in Europe and North America. Colonoscopy is the gold standard investigation for the colon but is not perfect, and small or flat adenomas can be missed which increases the risk of patients subsequently developing colorectal cancer. Adenoma detection rate is the most widely used marker of quality, and low rates are associated with increased rates of post-colonoscopy colorectal cancer. Standards of colonoscopy and adenoma detection vary widely between different endoscopists. Interventions to improve adenoma detection rate are therefore required. Many devices have been purported to increase adenoma detection rate. This review looks at current available evidence for device technology to improve adenoma detection rate during colonoscopy.

The NHS Bowel Cancer Screening Program: current perspectives on strategies for improvement

Colorectal cancer (CRC) is the third most common cancer in the UK. The English National Health Service (NHS) Bowel Cancer Screening Program (BCSP) was introduced in 2006 to improve CRC mortality by earlier detection of CRC. It is now offered to patients aged 60-74 years and involves a home-based guaiac fecal occult blood test (gFOBt) biennially, and if positive, patients are offered a colonoscopy. This has been associated with a 15% reduction in mortality. In 2013, an additional arm to BCSP was introduced, Bowelscope. This offers patients aged 55 years a one-off flexible sigmoidoscopy, and if several adenomas are found, the patients are offered a completion colonoscopy. BCSP has been associated with a significant stage shift in CRC diagnosis; however, the uptake of bowel cancer screening remains lower than that for other screening programs. Further work is required to understand the reasons for nonparticipation of patients to ensure optimal uptake. A change of gFOBt kit to the fecal immunochemical tests (FIT) in the English BCSP may further increase patient participation. This, in addition to increased yield of neoplasia and cancers with the FIT kit, is likely to further improve CRC outcomes in the screened population.

Virtual chromoendoscopy for the real-time assessment of colorectal polyps in vivo: a systematic review and economic evaluation

BACKGROUND

Current clinical practice is to remove a colorectal polyp detected during colonoscopy and determine whether it is an adenoma or hyperplastic by histopathology. Identifying adenomas is important because they may eventually become cancerous if untreated, whereas hyperplastic polyps do not usually develop into cancer, and a surveillance interval is set based on the number and size of adenomas found. Virtual chromoendoscopy (VCE) (an electronic endoscopic imaging technique) could be used by the endoscopist under strictly controlled conditions for real-time optical diagnosis of diminutive (≤ 5 mm) colorectal polyps to replace histopathological diagnosis.

OBJECTIVE

To assess the clinical effectiveness and cost-effectiveness of the VCE technologies narrow-band imaging (NBI), flexible spectral imaging colour enhancement (FICE) and i-scan for the characterisation and management of diminutive (≤ 5 mm) colorectal polyps using high-definition (HD) systems without magnification.

DESIGN

Systematic review and economic analysis.

PARTICIPANTS

People undergoing colonoscopy for screening or surveillance or to investigate symptoms suggestive of colorectal cancer.

INTERVENTIONS

NBI, FICE and i-scan.

MAIN OUTCOME MEASURES

Diagnostic accuracy, recommended surveillance intervals, health-related quality of life (HRQoL), adverse effects, incidence of colorectal cancer, mortality and cost-effectiveness of VCE compared with histopathology.

DATA SOURCES

Electronic bibliographic databases including MEDLINE, EMBASE, The Cochrane Library and Database of Abstracts of Reviews of Effects were searched for published English-language studies from inception to June 2016. Bibliographies of related papers, systematic reviews and company information were screened and experts were contacted to identify additional evidence.

REVIEW METHODS

Systematic reviews of test accuracy and economic evaluations were undertaken in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Meta-analyses were conducted, where possible, to inform the independent economic model. A cost-utility decision-analytic model was developed to estimate the cost-effectiveness of VCE compared with histopathology. The model used a decision tree for patients undergoing endoscopy, combined with estimates of long-term outcomes (e.g. incidence of colorectal cancer and subsequent morbidity and mortality) derived from University of Sheffield School of Health and Related Research's bowel cancer screening model. The model took a NHS perspective, with costs and benefits discounted at 3.5% over a lifetime horizon. There were limitations in the data on the distribution of adenomas across risk categories and recurrence rates post polypectomy.

RESULTS

Thirty test accuracy studies were included: 24 for NBI, five for i-scan and three for FICE (two studies assessed two interventions). Polyp assessments made with high confidence were associated with higher sensitivity and endoscopists experienced in VCE achieved better results than those without experience. Two economic evaluations were included. NBI, i-scan and FICE are cost-saving strategies compared with histopathology and the number of quality-adjusted life-years gained was similar for histopathology and VCE. The correct surveillance interval would be given to 95% of patients with NBI, 94% of patients with FICE and 97% of patients with i-scan.

LIMITATIONS

Limited evidence was available for i-scan and FICE and there was heterogeneity among the NBI studies. There is a lack of data on longer-term health outcomes of patients undergoing VCE for assessment of diminutive colorectal polyps.

CONCLUSIONS

VCE technologies, using HD systems without magnification, could potentially be used for the real-time assessment of diminutive colorectal polyps, if endoscopists have adequate experience and training.

FUTURE WORK

Future research priorities include head-to-head randomised controlled trials of all three VCE technologies; more research on the diagnostic accuracy of FICE and i-scan (when used without magnification); further studies evaluating the impact of endoscopist experience and training on outcomes; studies measuring adverse effects, HRQoL and anxiety; and longitudinal data on colorectal cancer incidence, HRQoL and mortality.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42016037767.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Editorial: The Name Game: Circumventing Quality Metrics by Categorizing Incomplete Colonoscopy as Sigmoidoscopy

Cecal intubation rate (CIR) is an important metric for colonoscopy quality. Guidelines propose a minimum CIR of 90% for all indications, and 95% in screening procedures. In this issue, a study of three UK teaching hospitals demonstrated one-third of endoscopists inappropriately converted colonoscopies to flexible sigmoidoscopies, and several endoscopists only reached the 90% CIR benchmark because of these inappropriate conversions. Our professional societies and healthcare organizations must continue to work to improve the accurate assessment of colonoscopy quality in order to identify underperforming clinicians who should be provided with additional training for the benefit of their patients.

The Conversion of Planned Colonoscopy to Sigmoidoscopy and the Effect of this Practice on the Measurement of Quality Indicators

OBJECTIVES

A cecal intubation rate (CIR) of >90% is a well-accepted quality indicator of colonoscopy and is consequently monitored within endoscopy units. Endoscopists' desire to meet this target may mean that incomplete colonoscopies are recorded as flexible sigmoidoscopies. The aim of this study was to examine whether the conversion of requested colonoscopies is a clinically significant phenomenon and whether this impacts upon the measurement of quality indicators.

METHODS

A retrospective review of all flexible sigmoidoscopies performed between 1 January 2015 and 31 December 2015 at Nottingham University Hospitals, Sheffield Teaching Hospitals, and Cambridge University Hospitals was performed. Where a colonoscopy was requested but a flexible sigmoidoscopy performed, the patient's records and endoscopy reports were reviewed to determine whether this conversion was decided before the start of the procedure and documented.

RESULTS

During the 12-month period, 6,839 flexible sigmoidoscopies were performed by 125 endoscopists. The original requests of 149 sigmoidoscopies could not be retrieved and were therefore excluded from this analysis. Of the 6,690 sigmoidoscopy requests reviewed, 2.8% (n=190) procedures were originally requested as a colonoscopy. On review of patient records, 85 conversions were appropriate according to pre-defined criteria. However, 105 conversions were deemed inappropriate, occurring in patients who had a valid documented indication for colonoscopy and had undergone full bowel preparation. The most common reasons cited included poor bowel preparation (n=37), technically challenging procedure (n=24), at the endoscopist's discretion based on clinical factors (n=21), and obstructing patology (n=8). A clear reason for conversion was not apparent in 11 cases. During the study period, 21,271 colonoscopies were performed and so conversions represent 0.45% of the total requests. When inappropriate conversions were included in individuals' performance data, 15 endoscopists fell to ≤90% target cecal intubation target.

CONCLUSIONS

A small, but significant number of colonoscopies are converted to flexible sigmoidoscopies at the time of the procedure. This study demonstrates the conversion of colonoscopy to sigmoidoscopy as being a potential limitation of relying on CIR alone. Endoscopy units should consider monitoring the rate of inappropriate conversions to ensure quality.

Macroscopic findings, incidence and characteristics of microscopic colitis in a large cohort of patients from the United Kingdom

OBJECTIVE

Microscopic colitis (MC) is classically associated with normal or near-normal endoscopic appearances. However, non-specific macroscopic findings have been described, the importance of biopsy location for confirming a diagnosis of MC is unclear, and reported incidence data from the United Kingdom are limited. This study was designed to assess macroscopic features, incidence, demographics, and location and positivity of biopsy samples in MC.

MATERIALS AND METHODS

Retrospective, cross-sectional study of individuals with newly diagnosed MC.

RESULTS

From 2010 to 2015, 540 cases of MC were reported. Macroscopic findings occurred in 16.5% (n = 89) cases, with trends towards increased frequency of ulceration or linear scarring in collagenous colitis (CC). The mean incidence of MC was 11.3 per 100,000 population/year, including 291 (53.9%) with CC (incidence 6.1 per 100,000/year), 203 (37.6%) with lymphocytic colitis (incidence 4.2 per 100,000/year) and 46 (8.5%) with MC, not otherwise specified. Most individuals were female (70.2%). Common features in patients with MC included symptom duration <6 months, weight loss, abdominal pain and use of proton pump inhibitors, statins, or non-steroidal anti-inflammatory drugs. In individuals with right- and left-sided biopsies taken, 98.2% had diagnostic features in both. However, rectal biopsies were only positive in 88.7%.

CONCLUSIONS

One in six patients with MC demonstrated distinct macroscopic findings at colonoscopy. Our data confirm a female preponderance in MC, a relatively short symptom duration and use of certain drugs as common features. Both right- and left-sided biopsies were frequently positive, suggesting flexible sigmoidoscopy and biopsy could confirm a diagnosis in certain individuals.

Training in Endoscopy: Colonoscopy

Colonoscopy is effective in reducing the morbidity and mortality associated with colorectal cancer (CRC). Interval cancers or post-colonoscopy CRCs, are cancers detected within the surveillance interval, or between 6–36 months after a clearing colonoscopy. The incidence of interval cancers is 3.4%–9.2% of all detected CRCs, as reported in population-based studies. Colonoscopy is a technically difficult procedure that is challenging to learn, and needs time and effort to gain competency. Therefore, trainee competence is a critical component of CRC screening and surveillance. Herein, we review the colonoscopy training methods and quality assessment metrics for colonoscopy competency.

Quality Indicators in Colonoscopy

OPINION STATEMENT

Colonoscopy is one of the most commonly performed endoscopic procedures. It is the gold standard examination for work-up of colonic symptoms, for follow-up of positive colorectal cancer screening tests and for detection and removal of neoplastic polyps. Colonoscopy is a complex and invasive procedure with a potential not only for colorectal cancer prevention, but also for serious complications. Numerous factors may affect the balance of benefit versus harm of colonoscopy, including the performance of the endoscopist. These factors are commonly called quality indicators. As an increasing number of countries are recommending the general population to undergo colorectal cancer screening, the quality of colonoscopy should be considered a public health concern. Key quality indicators have been identified, and several professional organizations have issued recommendation statements to promote high-quality colonoscopy. To achieve high quality, these key quality indicators must be monitored, results must be analysed, and measures must be undertaken to correct substandard performance. High-quality training in colonoscopy and polypectomy should be a quality assurance priority.

Adenoma surveillance and colorectal cancer incidence: a retrospective, multicentre, cohort study

BACKGROUND

Removal of adenomas reduces colorectal cancer incidence and mortality; however, the benefit of surveillance colonoscopy on colorectal cancer risk remains unclear. We examined heterogeneity in colorectal cancer incidence in intermediate-risk patients and the effect of surveillance on colorectal cancer incidence.

METHODS

We did this retrospective, multicentre, cohort study using routine lower gastrointestinal endoscopy and pathology data from patients who, after baseline colonoscopy and polypectomy, were diagnosed with intermediate-risk adenomas mostly (>99%) between Jan 1, 1990, and Dec 31, 2010, at 17 hospitals in the UK. These patients are currently offered surveillance colonoscopy at intervals of 3 years. Patients were followed up through to Dec 31, 2014.We assessed the effect of surveillance on colorectal cancer incidence using Cox regression with adjustment for patient, procedural, and polyp characteristics. We defined lower-risk and higher-risk subgroups on the basis of polyp and procedural characteristics identified as colorectal cancer risk factors. We estimated colorectal cancer incidence and standardised incidence ratios (SIRs) using as standard the general population of England in 2007. This trial is registered, number ISRCTN15213649.

FINDINGS

253 798 patients who underwent colonic endoscopy were identified, of whom 11 944 with intermediate-risk adenomas were included in this analysis. After a median follow-up of 7·9 years (IQR 5·6-11·1), 210 colorectal cancers were diagnosed. 5019 (42%) patients did not attend surveillance and 6925 (58%) attended one or more surveillance visits. Compared to no surveillance, one or two surveillance visits were associated with a significant reduction in colorectal cancer incidence rate (adjusted hazard ratio 0·57, 95% CI 0·40-0·80 for one visit; 0·51, 0·31-0·84 for two visits). Without surveillance, colorectal cancer incidence in patients with a suboptimal quality colonoscopy, proximal polyps, or a high-grade or large adenoma (≥20 mm) at baseline (8865 [74%] patients) was significantly higher than in the general population (SIR 1·30, 95% CI 1·06-1·57). By contrast, in patients without these features, colorectal cancer incidence was lower than that of the general population (SIR 0·51, 95% CI 0·29-0·84).

INTERPRETATION

Colonoscopy surveillance benefits most patients with intermediate-risk adenomas. However, some patients are already at low risk after baseline colonoscopy and the value of surveillance for them is unclear.

FUNDING

National Institute for Health Research Health Technology Assessment, Cancer Research UK.

Long-term risk of colorectal cancer after negative colonoscopy in a Danish gFOBT screening cohort

Faecal occult blood test (FOBT) screening for colorectal cancer (CRC) is implemented in several countries. Approximately half of all screen positive persons have negative colonoscopy, but consensus is lacking on how these persons should be followed up. Health authorities in Denmark and The Netherlands recommend suspending screening for 8-10 years, while patients in UK are invited to screening after 2 years. In this cohort-study, we followed 166,277 individuals invited to FOBT-screening in 2005-2006 and a reference group comprising the remaining 1,240,348 Danes of the same age. We linked Danish population and health service registers to obtain information about colonoscopy outcome and incident CRC. We estimated CRC risk by colonoscopy outcome (adenoma, other colorectal pathology or negative colonoscopy) for the reference group, the screening group, and subgroups. Persons with positive screening FOBT followed by negative colonoscopy had the same long-term CRC risk as persons with adenoma detected due to a positive screening FOBT (aHR 1.33, 95% CI: 0.65-2.71). We found no difference in the long-term CRC risk between persons with negative colonoscopy after a positive FOBT screening test and the unscreened reference population (aHR 1.05, 95% CI: 0.62-1.78). Since FOBT screen positive persons in our study remained at average risk of CRC despite of a negative index colonoscopy, we question the safety of suspending FOBT screening for this group. It needs to be monitored whether recent efforts to improve colonoscopy quality have been successful in ensuring low CRC risk after negative colonoscopy also in FOBT positive persons.

Unexpected complication of colonoscopy

The authors present a rare case of a 71-year-old man presenting with large bowel obstruction after attempted colonoscopy. The procedure was impossible to complete due to a tight sigmoid stricture and the patient presented with an acute abdomen the following day. He was managed conservatively and discharged before returning for an elective laparoscopic sigmoid colectomy. The potential differentials of an acute abdomen post-colonoscopy are discussed and the literature reviewed on this rare complication. Finally, the authors review whether there is pressure on endoscopists to 'complete' colonoscopies (by achieving caecal intubation) based on regulatory indices in quality, and how this might have to be disregarded in unfavourable circumstances.

Expert opinions and scientific evidence for colonoscopy key performance indicators

Colonoscopy is a widely performed procedure with procedural volumes increasing annually throughout the world. Many procedures are now performed as part of colorectal cancer screening programmes. Colonoscopy should be of high quality and measures of this quality should be evidence based. New UK key performance indicators and quality assurance standards have been developed by a working group with consensus agreement on each standard reached. This paper reviews the scientific basis for each of the quality measures published in the UK standards.

Review: capsule colonoscopy-a concise clinical overview of current status

The colon capsule endoscopy (CCE) was first introduced in 2007. Currently, the main clinical indications for CCE are completion of incomplete colonoscopy, polyp detection and investigation of inflammatory bowel disease (IBD). Although conventional colonoscopy is the gold standard in bowel cancer screening, incomplete colonoscopy remains a problem as lesions are missed. CCE compares favourably to computer tomography colonography (CTC) in adenoma detection and has therefore been proposed as a method for completing colonoscopy. However the data on CCE remains sparse and current evidence does not show its superiority over CTC or conventional colonoscopy in bowel cancer screening. CCE also seems to show good correlation with conventional colonoscopy when used to evaluate IBD, but there are not many published studies at present. Other significant limitations include the need for aggressive bowel preparation and the labour-intensiveness of CCE reading. Therefore, much further software and hardware development is required to enable CCE to fulfill its potential as a minimally-invasive and reliable method of colonoscopy.