Bowel Cancer Screening Programme Colonoscopy Research Articles

Colorectal polyp outcomes after participation in the seAFOod polyp prevention trial: Evidence of rebound elevated colorectal polyp risk after short-term aspirin use.

The seAFOod polyp prevention trial was a randomised, placebo-controlled, 2 × 2 factorial trial of aspirin 300 mg and eicosapentaenoic acid (EPA) 2000 mg daily in individuals who had a screening colonoscopy in the English Bowel Cancer Screening Programme (BCSP). Aspirin treatment was associated with a 20% reduction in colorectal polyp number at BCSP surveillance colonoscopy 12 months later. It is unclear what happens to colorectal polyp risk after short-term aspirin use. To investigate colorectal polyp risk according to the original trial treatment allocation, up to 6 years after trial participation. All seAFOod trial participants were scheduled for further BCSP surveillance and provided informed consent for the collection of colonoscopy outcomes. We linked BCSP colonoscopy data to trial outcomes data. In total, 507 individuals underwent one or more colonoscopies after trial participation. Individuals grouped by treatment allocation were well matched for clinical characteristics, follow-up duration and number of surveillance colonoscopies. The polyp detection rate (PDR; the number of individuals who had ≥1 colorectal polyp detected) after randomization to placebo aspirin was 71.1%. The PDR was 80.1% for individuals who had received aspirin (odds ratio [OR] 1.13 [95% confidence interval 1.02, 1.24]; p = 0.02). There was no difference in colorectal polyp outcomes between individuals who had been allocated to EPA compared with its placebo (OR for PDR 1.00 [0.91, 1.10]; p = 0.92). Individuals who received aspirin in the seAFOod trial demonstrated increased colorectal polyp risk during post-trial surveillance. Rebound elevated neoplastic risk after short-term aspirin use has important implications for aspirin cessation driven by age-related bleeding risk. ISRCTN05926847.

Economic impact of implementing optical diagnosis with a "resect and discard" strategy within the English Bowel Cancer Screening Programme: Findings from the DISCARD3 study.

Advances in endoscopic technology, such as narrow band imaging and high definition colonoscopes, offer the potential for optical diagnosis (OD) with a "resect and discard" (RD) strategy for diminutive (≤5mm) and small (6-9mm) colorectal polyps. This could help alleviate the huge cost and time burden required for histopathology. The aim of this study is to conduct an economic analysis of a RD strategy within the English Bowel Cancer Screening Programme (BCSP). A decision tree was designed to compare a RD strategy with standard histopathology for patients included in the DISCARD3 study and was extrapolated to a national BCSP patient cohort. Of the 525 patients in the DISCARD3 study, 354 were assessed for surveillance intervals (after excluding cases with colorectal cancer and at least one polyp >10 mm). 269/354 cases had polyps of which, 182 had only diminutive polyps, 77 had both small and diminutive polyps, and 10 had only small polyps. Surveillance interval concordance was 97.9% in patients with at least 1 diminutive polyp and 98.7% in patients with at least 1 diminutive or small polyp. In DISCARD3, a RD approach would reduce overall direct healthcare costs by £35,468.8 (-72.3%) for patients with diminutive polyps or by £42,666.2 (-75.0%) for patients with diminutive or small polyps. When extrapolated to the entire English BCSP, the annual savings are almost £2.4m for patients with diminutive polyps or £3.4m for patients with diminutive or small polyps, after adjusting for the costs of an OD quality assurance process (QAP). OD with a RD strategy for diminutive and small polyps during BCSP colonoscopy would offer substantial cost savings without adversly affecting surveillance interval concordance.

Impact of cumulative experience on the quality of screening colonoscopy: A 13-year observational study.

To investigate trends in quality of screening colonoscopy (using the Global Rating Score) in the 13 years since introduction of the Bowel Cancer Screening Programme in England. An English Bowel Cancer Screening Programme colonoscopy service from 2007 to 2019. A retrospective observational study was undertaken using a prospectively collected database in order to analyse trends in screening endoscopies (including patients following positive faecal occult blood test or with high-risk findings on flexible sigmoidoscopy). The Global Rating Score quality indicators for Bowel Cancer Screening Programme colonoscopy were used as outcome measures, and trends over time were analysed. These included caecal intubation rate, adenoma detection rate, colorectal cancer detection rate, proportion of patients with minimal or mild discomfort scores, proportion of patients who required intravenous sedation, and adverse events. There were 5352 colonoscopies included, performed by 3 endoscopists; 73.8% were index procedures (i.e. first Bowel Cancer Screening Programme colonoscopy) and the remainder were follow-up or surveillance colonoscopies. The mean age of patients was 66 (standard deviation 5) years, and 59.8% were male. Mean age increased over time (R2=0.033; p < 0.001). There were significant trends over time towards higher caecal intubation rate (p = 0.015), higher adenoma detection rate (p < 0.001), lower proportion requiring intravenous sedation (p < 0.001). There were no significant trends in comfort scores (p = 0.606), adverse events (p = 0.503) or colorectal cancer detection (p = 0.089). There was a consistent improvement in the Global Rating Score for Bowel Cancer Screening Programme colonoscopies since the start of the programme, even when quality was already high at the start. Patients can expect high-quality colonoscopy when participating in the Bowel Cancer Screening Programme.

PWE-122 Non-Bowel Cancer Screening Colonoscopy Has’Inferior Rates of Polyp Retrieval and Adenoma Detection than Bowel Cancer Screening

Introduction Colonoscopy within the Bowel Cancer Screening Programme (BCSP) is scrutiny to high national standards and enhanced quality assurance. These include accredited colonoscopists who are required to have passed a summative assessment and perform more than 150 BCSP colonoscopies annually. Additionally, extended time allocation to allow for longer withdrawal times, are thought to further improve quality. In contrast, patients attending for non-BCSP (NBCSP) may have their colonoscopy performed by any endoscopist with less time allocation. Adenoma detection rate (ADR) a key quality indicator of colonoscopy with the strongest association to post-colonoscopy colorectal cancer. We hypothesised that patients within the BCSP had a superior ADR to NBCSP patients and consequently, a higher quality colonoscopy. Methods Patients attending for BCSP and NBCSP colonoscopy over a 2 year period (August 2013–July 2015) at University College London Hospital were identified. NBCSP patients aged 60–74 years were only included in our analyses. BCSP colonoscopy was performed by one of 6 BCSP accredited colonoscopists. NBCSP colonoscopy was performed either by a nurse endoscopist, registrar (including those in training) or a consultant. An in-house endoscopy and BCSP database were used to record polyp detection (PDR), polyp retrieval (PRR), adenoma to polyp detection rate (APDR) and adenoma detection rates (ADR) in both groups. The Student’s t-test was used and p Results A total of 1,547 and 5,898 patients attended for BCSP and NBCSP colonoscopy. In the NBCSP group, 1,692 (29%) were aged 60–74 years and were only included in our analyses. The polyp detection rate (PDR) in the BCSP group was significantly higher (931/1547, 60%) than in the NBCSP group (465/1692, 27%), p The APDR was similar between both groups - BCSP 1,542/2,086 (74%), NBCSP 572/764 (75%). In contrast, the ADR was significantly higher in the BCSP cohort (735/1547 patients had >=1 adenoma, 48%) compared to the NBCSP group (337/1692 patients had >=1 adenoma, 20%), p Conclusion To our knowledge, this is one of the largest multi-operator studies comparing quality indicators in BCSP and NBCSP patients. Our study has demonstrated that NBCSP patients are more likely to have a significantly lower PRR and ADR than their BCSP counterparts. Further efforts should be made to address this disparity to help drive equality between these two services. Disclosure of Interest None Declared

OC-077 Does Faecal Occult Blood Testing Help Identify Ileo-Colonic Neuroendocrine Tumours in the UK Bowel Cancer Screening Programme (BCSP)?

Introduction There has been an increase in the incidence of ileo-colonic NETs in recent years, partly from endoscopy. There is no published data on the incidence of NETs diagnosed in the UK ‘double’ screen BCSP of initial Faecal Occult Blood stool test (FOBt) and, if abnormal, colonoscopy. The incidence (per 100 k) of colorectal cancer (CRC) in FOBt abnormal UK BCSP colonoscopy is 55 times that of the population incidence (10 k vs 184). 1 The aim of this study was to identify NETs diagnosed and recorded at UK BCSP colonoscopy between 2005–14. Methods Data requests were made to UK BCSP for details of screened populations, abnormal FOBts, and colonoscopies performed and CRCs diagnosed. NET related queries were run across 3 database tables; ‘Polyp Histology Polyp Architecture’, ‘Lesion Type’, ‘Histology Snomed’. Incidence (per 100 k) was compared with those from the SEER database; 2 small intestine and colorectal NETs 2.4; rectal 0.9, other colonic 0.4, appendiceal 0.2, small intestine 0.9. Results 13 million people completed FOBt screening with 260 k abnormal FOBt and 217 k colonoscopies. 146 NETs were identified with an incidence of 67 (per 100 k colonoscopies). The incidence of NETs (per 100 k colonoscopies) by site was 29 rectal, 18 other colonic, 1 appendiceal, and 11 small intestine. Ratios of BCSP to SEER incidences was 29 overall NET, 32 rectal, 45 other colonic, 5 appendiceal, and 12 small intestine. Conclusion The incidence of NETs at UK BCSP colonoscopy following an abnormal FOBt is markedly higher than the SEER population incidence. The effect is greatest for rectal and other colonic NETs although less than that seen with CRC (55 x) following FOBt screening. There is no published data on the incidence of small intestine NETs identified from terminal ileum intubation during ‘single’ or ‘double screen’ BCSP. However, the rectal NET incidence in the UK FOBt BCSP is lower (29 per 100 k colonoscopies) than that published from ‘single screen’ colonoscopy-only BCSP (50–70 per 100 k colonoscopies). 3 This suggests endoscopic screening itself is more helpful than FOBt screening in identifying rectal NETs. References 1 Logan RF, Patnick J, Nickerson C, et al . Outcomes of the Bowel Cancer Screening Programme (BCSP) in England after the first 1 million tests. Gut 2012; 61 (10):1439–1446. 2 Modlin IM, Lye KD, Kidd M. A 5-decade analysis of 13,715 carcinoid tumours. Cancer 2003; 97 (4):934–959. 3 Kaminski M, Polkowski M, Regula J. Prevalence and endoscopic features of rectal neuroendocrine tumours (carcinoids) among 50148 participants of the Polish colorectal-cancer screening programe. Gut 2007; 56 (Suppl III): A310. Disclosure of Interest None Declared

Tu2087 The First Randomised Controlled Trial of Endocuff Vision® Assisted Colonoscopy Versus Standard Colonoscopy for Polyp Detection in Bowel Cancer Screening Patients (E-CAP study)

Introduction Up to 25% polyps are missed during colonoscopy. The Endocuff Vision® is a cap with soft flexible arms that attaches to the colonoscope tip and improves views during withdrawal. We have performed the first randomised controlled trial to identify the role of Endocuff Vision® in improving polyp detection. We aim to investigate the impact of Endocuff Vision® assisted colonoscopy on polyp detection, as compared to standard colonoscopy, in the UK Bowel Cancer Screening Programme (BCSP). Methods Single centre, parallel group, randomised controlled trial. Ethics ref: 14/SC/0207. Adopted on UKCRN portfolio (ID: 16985). Patients attending for BCSP colonoscopy were stratified based on attendance for index screening colonoscopy or for polyp surveillance. Within each stratum participants were randomised to either Standard or Endocuff assisted colonoscopy. All procedures were performed by accredited BSCP endoscopists, who have carried out > 5000 colonoscopies and have caecal intubation rates of >90%. Results 534 patients recruited from Sep 2014 to Sep 2015. 3 excluded due to new diagnosis of polyposis syndrome. 531 were included and randomised to the 2 study arms. No significant difference was seen between the 2 groups for the primary endpoint of number of polyps per patient. Secondary endpoints: No significant difference was observed between the 2 groups for adenoma detection rate (ADR) or number of adenomas per patient (Table 1). No significant adverse events were encountered during the study in either arm. The cecal intubation time was not prolonged and patients did not experience any additional discomfort due to the Endocuff Vision. Conclusion In the UK, bowel cancer screening is performed by highly experienced endoscopists. Our results suggest that in expert hands, ADR exceeds 60% even without Endocuff. In such settings, Endocuff Vision did not improve polyp detection rates (PDR) or ADR. However, it did not cause any adverse events, prolong procedure duration or cause additional discomfort. These data demonstrate the safety and feasibility of Endocuff. However, no additional gain was demonstrated in expert hands. Disclosure of Interest None Declared

Ethnic variation in colorectal cancer risk following a positive faecal occult blood test in an English bowel cancer screening programme centre.

The literature on colorectal cancer (CRC) screening and ethnic diversity is dominated by studies from the USA. There are no such published data from the UK bowel cancer screening programme (BCSP) population. The Wolverhampton Bowel Cancer Screening Centre serves a population of 900,000 in the Black Country and South Staffordshire. South Asians (SA) comprise 9% of the population. We aimed to determine the effects of ethnicity and sex on the risk for cancer or adenoma detected by colonoscopy following a positive faecal occult blood test over a 5-year period (2007-2011). Data were collected from the prospectively maintained BCSP cohort. South Asian patients were identified and compared with those of non-South Asian ethnicity, and colonoscopy outcomes were determined. A total of 3552 participants underwent BCSP colonoscopy (non-South Asian=3363; SA=189). There were 271 cancers (7.6%) detected within the non-South Asian group and seven cancers (0.2%) in the South Asian population (P<0.05). The probability of colon cancer is higher [odds ratio (OR)=3.84, P<0.05] in non-South Asians compared with South Asians. Patients in the 65-70-year age group have the highest risk (OR=1.60; P<0.05) for CRC. During the study 1313 adenomas were detected. A total of 771 high-risk and intermediate-risk adenomas were detected in the non-South Asian group, and 14 were detected in the South Asian group. The risk of adenoma in non-South Asians is six times higher than in South Asians (OR=5.99, P<0.001) following positive faecal occult blood testing. There are fewer colorectal cancers in South Asians compared with the non-South Asian population in this regional study. This is the first such study in the BCSP population.

PWE-360 Outcomes of failed colonoscopy within the bowel cancer screening programme (BCSP)

<h3>Introduction</h3> The NHS BCSP uses colonoscopy as the primary colonic investigation following a positive faecal occult blood screening test. The standards for completion of colonoscopy are high within the programme and well above the target of 90%. Whilst there is clear guidance for use of a ‘second test’ to complete colonic imaging in that minority with a ‘failed’ index colonoscopy,¹little is known about the outcome of these patients. The aim of this study was to determine the outcome of patients following a failed BCSP colonoscopy. <h3>Method</h3> All patients that underwent a BCSP colonoscopy at Royal Liverpool University Hospital between 2008–2013 were identified. All cases of failed colonoscopy were fully audited with a minimum of 12 months follow up and comparisons were made with those within the BCSP with completed examinations (Chi-Squared statistical analysis). <h3>Results</h3> In the study period 2885 BCSP colonoscopies were performed, caecal intubation rate was 96%. From the 111 failed procedures, 26 (23%) were due to obstructing colorectal cancer (CRC). 108 patients underwent a second test: 67 (62%) had CT colonography, 23 (21%) had a CT abdomen, 17 (16%) had a repeat colonoscopy, 2 (2%) had a barium enema. 3 (3%) patients did not have a second test: 2 declined, and 1 died of cardiac causes post orthopaedic surgery whilst awaiting their test. Once the patients with significant positive findings on the index colonoscopy were excluded (e.g. cancer diagnosis), the risk of finding additional significant pathology on second test was 49%. Sub-categorised, the risk of CRC, extra-colonic malignancy and polyps was 2.3%, 2.3% and 44% respectively. Whilst the risk of finding CRC on the second test was similar to a completed procedure (2.3% vs. 3.2% respectively; p = 0.66), the risks of finding polyps was unsurprising lower (second test 44% vs. complete colon 61%: p &lt; 0.001). The 12-month outcome of patients with failed colonoscopy found that 53% returned to the BCSP, 19% were enrolled to BCSP surveillance and 25% were offered a definitive treatment after MDT (all CRC patients). The 12-month mortality was just 3%: 2 having died from non-GI malignancy and 1 from cardiac causes. <h3>Conclusion</h3> This study emphasises the importance of complete colonic examination within the BCSP. For those with an incomplete colonoscopy not caused by an obstructing tumour, there was a 49% chance of finding significant pathology on the second test. The lower incidence of polyps found on the second test confirms colonoscopy as the gold standard for polyp detection. Overall the outcomes are good with just 3% mortality at 12 months (unrelated to CRC) even with a diagnosis of CRC in almost a quarter of cases. <h3>Disclosure of interest</h3> None Declared. <h3>Reference</h3> Taylor S <i>et al</i>. Guidelines for the use of imaging in the NHS Bowel Cancer Screening Programme. 2nd edition. 2012.

PTU-019 Pain, perception and reality – comparison of comfort scores of south asian and white british patients undergoing bowel cancer screening colonoscopy:

<h3>Introduction</h3> There have been several studies suggesting South Asian patients have differing pain perception to White British patients.¹Watson <i><i>et al</i>.</i>compared hot and cold pain perception in 20 age-matched South Asian and White British volunteers, with significantly increased heat pain scores and reduced pain threshold.² Recently, Al-Hashimi <i><i>et al</i></i>showed no significant differences in post-operative pain scores and analgesia consumption in 60 South Asian patients undergoing total abdominal hysterectomy versus 60 age-matched White British controls.³ Sedation and analgesia administration is well regulated in colonoscopy practice and comparing comfort scores in similar aged South Asian and White British screening patients is of interest to bowel cancer screening programme (BCSP) centres in ethnically diverse areas. <h3>Method</h3> In 2014, colonoscopy screened individuals (BCSP) in Leicester and Kettering had their self-selected ethnic origin recorded. Comfort scores of 713 patients recorded in the Exeter online database was correlated to ethnic origin data and analysed. <h3>Results</h3> Total number of patients: 713 Difference between means: 0.26 (95% CI: 0.05–0.47) <h3>Conclusion</h3> This analysis shows mean comfort scores are significantly <i>lower</i>in South Asian patients (p = &lt;0.02). This is counter to what published literature might suggest. We reported in 2014 that South Asian patients undergoing BCSP colonoscopy have significantly lower adenoma detection rates when compared to White British patients (31.68% vs 48.09% p = &lt;0.02). ⁴Perhaps fewer adenomas requiring polypectomy lead to more straightforward colonoscopy and lower comfort scores. Whatever the explanation, this analysis shows that pain perception is complex. The interaction of patient ethnicity factors (behavioural, cultural, social and psychological) are not easily predicted and requires further study. <h3>Disclosure of interest</h3> None Declared. <h3>References</h3> Edwards CL, Fillingim RB, Keefe F. Race, ethnicity and pain. Pain 2001; 94: 133–137 Watson PJ, Latif RK, Rowbotham DJ. Ethnic differences in thermal pain responses: a comparison of South Asian and White British healthy males. Pain 2005;118:194–200 Al-Hashimi M, Scott S, Griffin-Teall N, Thompson J. Influence of ethnicity on the perception and treatment of early post-operative pain. Pain 2014. doi: 10.1177/2049463714559254 Verma AM, Lewin V, Chilton AP, de Caestecker J, Dixon A, Jameson J, Wurm P, Robinson RJ. Variations in adenoma detection rate and cancer detection rate in individuals from different ethnic groups undergoing bowel cancer screening colonoscopy. Gut 2014;<b>63</b>(Suppl 1):A122

PTH-037 Do Patients with a Previous Negative Colonoscopy and Positive Fob Test Need a Bowel Cancer Screening Colonscopy?

IntroductionPatients with a positive faecal occult blood test invited for screening colonoscopy may have undergone previous colonoscopy. Excluding such patients from a repeat colonoscopy may reduce endoscopy waiting lists and...

PTH-069 Does Diverticulosis Protect Against Sigmoid Cancer?

IntroductionWith the advent of the English National Bowel Cancer Screening Programme (BCSP), a higher proportion of left-sided cancers than expected has been documented1. A high incidence of diverticular disease in...

PMO-223 Tattooing of suspicious colonic lesions at colonoscopy: is adherence to local protocol better if identified through the Bowel Cancer Screening Programme?

IntroductionThe Joint Advisory Group on gastrointestinal endoscopy and the National Bowel Cancer Screening Programme (BCSP) have published guidelines on the tattooing of malignant and suspicious lesions at colonoscopy. Our endoscopy...

PMO-212 Patients with positive faecal occult blood test (FOBt) following previous low risk colonoscopy in the bowel cancer screening programme: should current approach be changed?

IntroductionIn the UK FOBt Bowel Cancer Screening Programme (BCSP), patients between 60 and 75 are invited to submit stool specimens 2 yearly. Those who have either two weakly positive (+ve)...

PWE-076 Continued biennial screening of faecal occult blood test (FOBT) positive and screening colonoscopy negative cohort in English bowel cancer screening programme—is it necessary?

IntroductionThe English NHS Bowel Cancer Screening Programme (BCSP) uses guaiac based faecal occult blood test (FOBT) as the screening tool, with people with a positive result undergoing colonoscopy. Subjects with...

So many polyps, so little time: where will our bowel cancer screening colonoscopists come from?

IntroductionThe UK Bowel Cancer Screening Programme (BCSP) aims to reduce colorectal cancer death by removing colonic polyps from FOB positive patients between the ages of 60 and 69. The BCSP...

PTH-024 Obesity and colonoscopy: not so difficult after all? The experience of a bowel cancer screening unit

Introduction Obesity is a risk factor for the development of colorectal cancer (CRC).1 Colonoscopy in obese patients has been suggested to be more technically difficult,23 but variation in indication and age of patients, and operator technical ability may be confounding factors. The Bowel Cancer Screening Programme (BCSP) has a single indication for colonoscopy in a narrow age band (60–70 years) and the colonoscopists are of a proven standard, therefore studying data from this group of patients may avoid confounding factors and give a truer assessment of technical difficulty. Methods We compared measures of technical difficulty (quality of preparation; caecal intubation rate and time; sedation/analgesia dose; and patient tolerance) and findings (polyp and cancer detection) in the Taunton Faecal Occult Blood positive (FOB+ve) BCSP colonoscopy patients in 2008/9 (N=359, males 209, females 150) in relation to their BMI. Results BMI was known in 348, and was 15.7–58.3 (median 28.0). One hundred and eleven patients (31.8%) had BMI >30. Bowel preparation scores were not affected by BMI (Fisher9s Exact Test, p=0.62), nor were sedation and analgesia requirements (all comparisons obese vs non-obese, Fisher9s Exact Test or regression analysis). Comfort scores were similar (minimal or no discomfort 63% vs 68%, p=0.33). Overall caecal intubation rates were 96.3%, vs 97.4% (p=0.73). Caecal intubation time was not effected by BMI (r=0.022, p=0.68). Polyps were found in 210 (58.4%) patients and cancer in 43 (11.9%) in total. BMI did not affect the number of polyps found (p=0.33). There was no significant difference in the number of cancers identified in patients with a BMI>30 (14 of 97) compared to the others (29 of 208) (p=1.0). Conclusion Obesity does not impair the technical performance of colonoscopy in this population. There is a high rate of obesity in the FOB +ve BCSP population, but the effect of obesity on findings cannot be assessed by this study, since the proportion of obese patients in the overall population from which this group is drawn was not available. Nether-the-less this study suggests that obesity should not be a factor in deciding whether colonoscopy is an appropriate investigation to exclude CRC.