Adenoma Detection Rate In Patients Research Articles

P267 Real-world artificial intelligence-aided colonoscopy does not improve adenoma detection rates in patients with Inflammatory Bowel Disease

Abstract Background Recently, the implementation of artificial intelligence-aided colonoscopy (AIAC) has resulted in improved performance of colorectal cancer (CRC) screening. The adenoma detection rate (ADR) is a key quality indicator in screening colonoscopies and achieving high ADRs is crucial for optimal prevention of CRC. Guidelines suggest that ADRs of 20% in women and 30% in males are indicative of adequate performance. Patients with inflammatory bowel disease (IBD) may be at increased risk for CRC based on disease extent and duration. However, ADR in patients with IBD can be generally lower than in average-risk patients, mainly due to an age gap and the presence of dysplasia associated lesions as opposed to sporadic adenomas. Indeed, there is no consensus for an accepted ADR target in these patients. In addition, the impact of AIAC on ADR in these patients has yet to be described. We aimed to explore the ADR of patients with IBD in a large-volume endoscopic center and evaluate the effect of AIAC on ADR. Methods This was a retrospective study conducted at a high-volume gastroenterology department where all endoscopy suites were equipped with an AIA device (GI Genius, Medtronic, Ireland) starting from July 1st 2021. Data was collected on all colonoscopies performed in the 11 months before the mentioned date and compared to a 15-month period afterwards. We excluded patients that performed colonoscopy due to evaluation of IBD severity, for known or suspected malignancy, therapeutic endoscopies, incomplete colonoscopies and colonoscopies with inadequate preparation. The primary outcome of the study was ADR. Results Our study included 996 colonoscopies (237 pre-AIAC, 759 AIAC). The groups were similar in age (median 43.8 years, interquartile ratio (IQR) 28.7-61.2 vs 44.5 years, IQR 30.7-59.1, p=0.76) and gender distribution (55.3% vs 54.3% males, p=0.82). In both groups, there were more Crohn’s disease (62.9% pre-AIAC, 57.2% AIAC, p=0.13) than ulcerative colitis patients. The ADR in the pre-AIAC group tended to be higher in comparison to AIAC (6.3% vs 4%, p=0.15); When limiting to experienced gastroenterologists only (≥ 5 years), ADR results were significant higher in the pre-AIAC group (7.6% vs 3.8%, p=0.035). In addition, total procedure time (considered the time from procedure start and end as recorded by the endoscopy nurse) was significantly shorter in the AIAC group (21 minutes, IQR 17-28 vs 25 minutes, IQR 19-37, p<0.0001). Conclusion In a large-volume tertiary center cohort, the introduction of AIAC to real-world colonoscopies did not improve ADR in patients with IBD, questioning the integration of AIAC in routine practice.

Liver Cirrhosis Increases the Risk of Developing Advanced Colon Polyps.

To analyze our experience with adenoma detection rates in patients with liver cirrhosis in a community setting. Colorectal cancer (CRC) is the third most common cancer and leading cause of cancer death in men and women in the USA. The majority of CRCs arise from premalignant polyps (adenomas), which are typically detected and removed during colonoscopy. Data are limited on the risk of CRC in patients with various chronic liver diseases and the association between CRC and demographics, liver disease etiology and colonoscopy findings. A total of 351 colonoscopies were performed (2006 to 2019) in patients with liver cirrhosis. Mean age was 62.3 ± 9.4years, there were 158 females and 193 males. Adenomas were found in 159 procedures (49.07%) and were more likely found in the right colon (76.73%) vs the left colon (18.87%). Left-sided adenoma occurrence was significantly lower in women (61% lower than men, p = 0.05). Neither indication for the procedure (p = 0.08) nor advancing age (p = 0.94) affected adenoma detection rates. No significant differences were observed in the findings of adenomas between different chronic liver diseases. Adenoma detection rates in patients with cirrhosis (49%) undergoing elective colonoscopy were higher than rates reported in the literature for LT candidates (22-42%) undergoing standardized screenings. Colonoscopy screenings should be expanded to all patients with cirrhosis, regardless of etiology.

Continuous ADR50 monitoring through automated linkage between endoscopy and pathology: a quality improvement initiative in a Brussels public hospital.

Adenoma detection rate in patients aged 50 years or older (ADR50) is considered by the European Society of Gastrointestinal Endoscopy (ESGE) a key performance measures for lower gastrointestinal endoscopy. Technical and human resources constrain implementation of recording quality monitoring. The aim was to deploy an infrastructure for continuous monitoring of endoscopy quality indicators. And to evaluate its potential benefit on quality performance. A company reporting system was adapted by adding a dedicated tab for quality monitoring, including: preparation, progression, number of resected polyps. Automated linkage with the pathology database resulted in continuous monitoring of inter alia: rate of adequate bowel preparation, cecal intubation rate and ADR50. Continuous monitoring was done for all nine endoscopists working at our center, with individual feedback after 4, 9 and 28 months. A total of 1434 colonoscopies were performed during the first 9 months of monitoring, 682 during the first 4 months, 752 during the following 5 months. Five months after feedback a global increase in ADR50 of 4.6% (22.9% to 27.5%) (P<0.05) was observed, compared to the first 4 months. Thus meeting the benchmark (≥25%) recommended by ESGE. A durable effect of monitoring and feedback was observed after 28 months (ADR50: 29.4%). An easy to use infrastructure for registration of quality monitoring in daily endoscopy practice, automatically linking the pathology database, facilitates continuous monitoring of endoscopy quality indicators. A global and durable ADR50 increase was observed after feedback, considered a quality improvement in performance of lower gastrointestinal endoscopy at our center.

Pre-endoscopic tachycardia predicts increased sedation dose and lower adenoma detection rate in patients undergoing endoscopic procedures: a case control study.

Tachycardia prior to endoscopic procedures is commonly encountered which reflect patient anxiety status. Despite this frequent occurrence, it is unclear if in a patient with tachycardia sedation dose should be modified. The aim of our study was to assess the effect of pre-endoscopic tachycardia on sedation dose. A retrospective analysis of all patients who underwent upper endoscopy and colonoscopy at EMMS Nazareth hospital were performed. We excluded patients with diseases and medications affecting the heart rate. A total of 2855 patients were included in the study. Two-hundred and thirty-seven patients had tachycardia before endoscopy (8.3%, group A) as compared to 2618 (group B) patients who had heart rate ≤100 beats per minute. The mean dosage of propofol in group A was significantly higher (62.6±33.2 mg vs. 57.4±29.9 mg) than in group B (P=0.01). There was no difference in the cecal intubation rate among the two groups (P=0.9). Notably, the adenoma detection rate was significantly lower among group A patients as compared to group B (13.6% vs. 22.8%, P=0.02) patients. There were no sedation related complications. Tachycardia prior to endoscopic procedures was associated with higher sedative dosage and lower adenoma detection rate, however no major complications were recorded. These data should be taken into consideration to optimize procedure quality.

Patients with non-colorectal cancers may be at elevated risk of colorectal neoplasia.

Background: Screening for colonic neoplasia has decreased the incidence of colorectal cancer in the United States in the past two decades. Whether personal history of noncolorectal cancer is a risk factor for colonic neoplasia has not been well studied. We assessed the risk of colorectal neoplasia in noncolorectal cancer survivors.Methods: We conducted a retrospective study of patients who had undergone colonoscopy for any indication between 2009 and 2018. Colonic adenoma detection rate and multivariate logistic regression were conducted to assess for the primary outcomes of the study.Results: The study included 9408 cancer patients and 3295 control patients. Colonic adenomas were detected in 4503 cancer patients (48%) and 950 cancer-free patients (29%). Histologic examination of these adenomas revealed tubulovillous features in 620 patients (5%) and villous in 153 (1%). High-grade dysplasia was detected in 1611 patients (13%). Invasive colorectal adenocarcinoma was detected in 455 patients (12%); this rate was highest in patients with multiple myeloma (14%). Multivariate analysis revealed that a personal history of noncolorectal cancer was associated with increased risk of adenoma (Odd ratio, 2.04; 95% CI, 1.84-2.26; P<0.001). The adenoma detection rate was 30% in patients younger than 40 years (n=1211), 32% in patients between 41 and 50 years (n=812), 47% in patients between 51 and 60 years (n=2892), and 55% in patients older than 60 years (n=4493).Conclusions: The adenoma detection rate in patients with a personal history of noncolorectal cancer is higher than the reported rate of the general population and our control group.

280 Patients With Non-Colorectal Cancers May Be at Elevated Risk of Colorectal Neoplasia

INTRODUCTION: Screening for colonic neoplasia has decreased the incidence of colorectal cancer in the United States in the past two decades. Whether personal history of noncolorectal cancer is a risk factor for colonic neoplasia has not been studied. We assessed the risk of colorectal neoplasia in noncolorectal cancer survivors. METHODS: We conducted a retrospective study of patients who had undergone colonoscopy for any indication between 2009 and 2018. Colonic adenoma detection rate and multivariate logistic regression were conducted to assess for the primary outcomes of the study. RESULTS: The study included 9408 cancer patients and 3295 control patients. Colonic adenomas were detected in 4503 cancer patients (48%) and 950 cancer-free patients (29%). Histologic examination of these adenomas revealed tubulovillous features in 620 patients (5%) and villous in 153 (1%). High-grade dysplasia was detected in 1611 patients (13%). Invasive colorectal adenocarcinoma was detected in 455 patients (12%); this rate was highest in patients with multiple myeloma (14%) (Table 1). Multivariate analysis revealed that a personal history of noncolorectal cancer was associated with increased risk of adenoma (Odd ratio, 2.04; 95% CI, 1.84–2.26; P &lt; 0.001). The adenoma detection rate was 30% in patients younger than 40 years (n = 1211), 32% in patients between 41 and 50 years (n = 812), 47% in patients between 51 and 60 years (n = 2892), and 55% in patients older than 60 years (n = 4493) (Figure 1). CONCLUSION: The adenoma detection rate in patients with a personal history of noncolorectal cancer is higher than the reported rate of the general population and our control group.

Endocuff Vision is safe to use for dysplasia surveillance in patients with ulcerative colitis: a feasibility study.

Background and study aims Endocuff Vision improves adenoma detection rates in patients without inflammatory bowel disease. This study aimed to investigate the safety and feasibility of Endocuff Vision-assisted high-definition white light endoscopy (HDWLE) with dye-spray chromoendoscopy for detection of dysplasia in patients with ulcerative colitis. Patients and methods Patients with clinically inactive ulcerative colitis due for dysplasia surveillance were recruited. Procedural endpoints included safety, cecal intubation rate (CIR), terminal ileum intubation rate (TIR), withdrawal time, polyp detection rate, dysplasia detection rate (DDR), and sessile serrated lesion detection rate. Results Twenty-five patients (9 female, median age 57 [range 28 – 82] years) were studied. Endocuff Vision-assisted HDWLE was completed in all participants, with a CIR of 100 %, in a median 4 minutes (range 2 – 16), and a TIR of 88% in a median of 6.5 minutes (range 3 – 19). Median withdrawal time was 18 minutes (range 10 – 55), including application of dye-spray, biopsies and polypectomy. The Mayo Endoscopic subscore was 0 in 11, 1 in 9, and 2 in 5 patients. The DDR was 24 % (6 patients had a total of 12 dysplastic lesions) and sessile serrated lesion detection rate was 12 % (3 patients had a total of 4 sessile serrated polyps). No serious adverse events occurred, with one patient developing clinically insignificant minor mucosal bleeding. Conclusion Endocuff Vision-assisted HDWLE is feasible and safe in patients with ulcerative colitis undergoing dysplasia surveillance. Further studies are required to assess superiority of this technique compared with standard high-definition white light endoscopy with chromoendoscopy.

Evaluation of the combined effect of factors influencing bowel preparation and adenoma detection rates in patients undergoing colonoscopy

BackgroundColonoscopy is a commonly used modality for screening and surveillance of colorectal cancer (CRC). Therefore, it is essential to have adequate bowel preparation (prep) for the procedure which depends on...

Adenoma Detection Rates in Patients in the 40-49 Year Age Group Across Different Ethnicities: Presidential Poster Award

Introduction: Colorectal cancer (CRC) is the third most commonly diagnosed cancer and the third leading cause of cancer related deaths in United States. Recent guidelines from the American Cancer Society (ACS) recommend starting CRC screening at 45 years in average-risk patient population in United States. Previous studies have shown an increase in incidence of CRC in African Americans less than 50 years of age. Despite this, there is limited evidence about prevalence of adenomatous polyps in this age group. We aimed to examine the prevalence of adenomas in 40 to 49 years old patients without any family history (FH) of CRC or polyps across different races. Methods: A retrospective cross sectional study was performed using our electronic endoscopy database. Study subjects included all 40 to 49-year-old patients without any FH of CRC undergoing their index colonoscopy at our tertiary care academic institution from January 1, 2010 to September 30, 2017. Exclusion criteria included patients who underwent colonoscopy for overt gastrointestinal bleeding, inflammatory bowel disease, patients who had previous colonoscopies, a history of familial adenomatous polyposis, hereditary non polyposis CRC. Results: A total of 1856 patients were included in the study. Of these 53.6 % were Caucasian, 26.9% African Americans, and 19.4 % were Hispanics. Mean age of these patients was 44.7 yrs (S.D 2.6) and 57.6 % were males. Adenoma detection rate (ADR) was 22.1 % in Caucasians, 16.0 % in African Americans, 23.3% in Hispanics (Table 1). On multivariate analysis while adjusting for possible confounding factors, African Americans had lower ADR as compared to Caucasians (adjusted Odds Ratio: 0.6, 95% CI: 0.4-0.8, P-value=0.001). Conclusion: The ADR across all races in the 40-49 year age group is lower than the previously recommended ADR in patients with average risk undergoing their screening colonoscopy at 50 years of age (i.e. 25%). With the advent of new guidelines from the ACS, new benchmarks for quality indicators in colonoscopy regarding ADR will be needed. The lower ADR in African Americans suggests that further studies are needed to look for factors beyond the traditional adenoma-carcinoma pathway to understand the increasing incidence of CRC in African Americans in the younger age group.478 Figure 1 No Caption available.

Sa1033 TIME TO RAISE THE BAR: A SYSTEMATIC REVIEW OF ADENOMA DETECTION RATE IN FIT POSITIVE POPULATIONS.

Adenoma detection rate (ADR) is defined as the percentage of patients undergoing screening colonoscopy who have one or more adenoma detected and is a well-known quality indicator for colonoscopy. Recent ASGE guidelines recommend ADR of >35% in females and >45% in males undergoing colonoscopy for positive FIT test. However it is a weak recommendation with very low quality of evidence. To estimate the average threshold of ADR in patients with positive FIT test who undergo colonoscopy. Online databases including Medline, PubMed, Google Scholar and Embase were searched from inception to October 2017 by two investigators. References from the ASGE guidelines were manually searched to include additional data. Studies describing the adenoma detection rate in asymptomatic patients with positive FIT tests were included for this review. We used MedCalc Ver 17.9.7 to estimate the weighted outcome of ADR across various studies. Random effects model was used for weighing. A total of 34 studies were identified for full review after literature search, of which 17 studies were found to be eligible for this study. A total of 103090 patients were included in the final analysis. The range of ADR across studies was (36.75%-77.19%) with a median of 54.59%. The combined weighted ADR was 52.18%, (95% CI 49.97-54.38) . There was substantial heterogeneity between the studies likely due to the use of different cut off values of the positive FIT result and different populations studied. Average adenoma detection rate in patients with positive FIT test appears to be higher than benchmark set by ASGE. Higher quality studies with more uniform data are required to accurately establish ADR threshold in this population.Forest plot depicting confidence limits of mean ADR across different studies.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

Association between diverticulosis and colonic neoplastic lesions in individuals with a positive faecal immunochemical test.

The association between diverticulosis and colonic neoplastic lesions has been suggested, but data in literature are conflicting. This study aimed to investigate such a relationship in patients participating in a colorectal cancer screening program who underwent high-quality colonoscopy. Data from consecutive individuals 50-75 years of age with a positive faecal immunological test were considered. Diverticulosis was categorised as present or absent. The prevalence of neoplastic lesions (adenoma, advanced adenoma, and cancer) between individuals with and those without diverticula was compared. A multivariate analysis was performed. Overall, data from 970 consecutive individuals were evaluated, and diverticulosis was detected in 354 (36.5%) cases. At least one adenoma was detected in 490 (50.5%) people, at least one advanced adenoma in 264 (27.2%), multiple adenoma in 71 (7.3%), whilst a cancer was diagnosed in 48 (4.9%) cases. At univariate analysis, the adenoma detection rate in patients with diverticula was significantly higher than in controls (55.9% vs 47.4%; p = 0.011). At multivariate analysis, presence of diverticulosis was an independent risk factor for both adenoma detection rate (OR = 1.58; 95% CI = 1.14-2.18; p = 0.006) and advanced adenoma (OR = 1.57; 95% CI = 1.10-2.24; p = 0.013), but not for colorectal cancer. In a colorectal screening setting, the adenoma detection rate was significantly higher in individuals with diverticulosis than in controls.

The ADENOMA Study. Accuracy of Detection using Endocuff Vision™ Optimization of Mucosal Abnormalities: study protocol for randomized controlled trial.

Background: Colonoscopy is the gold standard investigation for the diagnosis of bowel pathology and colorectal cancer screening. Adenoma detection rate is a marker of high quality colonoscopy and a high adenoma detection rate is associated with a lower incidence of interval cancers. Several technological advancements have been explored to improve adenoma detection rate. A new device called Endocuff Vision™ has been shown to improve adenoma detection rate in pilot studies. Methods/Design: This is a prospective, multicenter, randomized controlled trial comparing the adenoma detection rate in patients undergoing Endocuff Vision™-assisted colonoscopy with standard colonoscopy. All patients above 18 years of age referred for screening, surveillance, or diagnostic colonoscopy who are able to consent are invited to the study. Patients with absolute contraindications to colonoscopy, large bowel obstruction or pseudo-obstruction, colon cancer or polyposis syndromes, colonic strictures, severe diverticular segments, active colitis, anticoagulant therapy, or pregnancy are excluded. Patients are randomized according to site, age, sex, and bowel cancer screening status to receive Endocuff Vision™-assisted colonoscopy or standard colonoscopy on the day of procedure. Baseline data, colonoscopy, and polyp data including histology are collected. Nurse assessment of patient comfort and patient comfort questionnaires are completed post procedure. Patients are followed up at 21 days and complete a patient experience questionnaire. This study will take place across seven NHS Hospital Trusts: one in London and six within the Northern Region Endoscopy Group. A maximum of 10 colonoscopists per site will recruit a total of 1772 patients, with a maximum of four bowel screening colonoscopists permitted per site. Discussion: This is the first trial to evaluate the adenoma detection rate of Endocuff Vision™ in all screening, surveillance, and diagnostic patient groups. This timely study will guide clinicians as to the role of Endocuff Vision™ in routine colonoscopy.Study registration: ISRCTN11821044.

Mo1559 Evaluating the Optimal Time for Colonoscopy Withdrawal: a Prospective Randomized Comparison of 3 Minute Versus 6 Minute Withdrawal

Mo1559 Evaluating the Optimal Time for Colonoscopy Withdrawal: a Prospective Randomized Comparison of 3 Minute Versus 6 Minute Withdrawal Sheila Kumar*, Rajan Kochar, Shai Friedland, Uri Ladabaum, Ann M. Chen, Subhas Banerjee Division of Gastroenterology and Hepatology, Department of Medicine, Stanford University, Palo Alto, CA Introduction: A minimum withdrawal time for screening colonoscopy of 6 minutes has been proposed, based on an observational study, and has become the de-facto standard of care. The 6-minute withdrawal time remains controversial and has not been compared in a standardized fashion to alternative withdrawal times. Aims: To perform a prospective randomized study to compare Polyp Miss Rates, Adenoma Miss Rates and Adenoma Detection Rates in patients undergoing colonoscopy with a 3-minute versus a 6-minute withdrawal time. Methods: Consecutive patients undergoing colonoscopy at Stanford University and the Palo Alto Veterans Administration Hospital were enrolled. Patients were prospectively randomized to undergo colonoscopy with either a 3-minute or 6minute withdrawal time during the 1st pass. A second pass was then performed with a 6-minute withdrawal in both groups to determine Polyp Miss Rates and Adenoma Miss Rates. The Adenoma Detection Rate (#colonoscopies where at least 1 adenoma was detected on the first pass/total #colonoscopies) was also determined for both groups. Results: 107 patients (73 men, 24 women) have been enrolled. 52 underwent 3-minute withdrawal and 55 underwent 6-minute withdrawal. Indications and baseline characteristics for both groups were similar (Table 1). The Polyp Miss Rate was significantly higher in the 3-minute withdrawal group compared to the 6-minute withdrawal group (57% vs. 26%, p 0.0012). The Adenoma Miss Rate was also significantly higher in the 3-minute withdrawal group compared to the 6-minute withdrawal group, (57% vs. 33%, p 0.013) (Table 2). The Adenoma Detection Rates were similar in both groups (31% vs. 24%, p NS). Conclusion: The Polyp Miss Rate and Adenoma Miss Rate were significantly higher in the 3-minute withdrawal group compared to the 6minute withdrawal group, suggesting that a 3-minute withdrawal may be inadequate and that a 6-minute withdrawal may be more appropriate for colorectal cancer screening. No significant difference was noted in the Adenoma Detection Rate between the two groups, which may be due to inadequate sample size.

856 Final Results of Phase II, Open Label, Study Investigating Polyp and Adenoma Detection Rate After Single Oral Dose of Methylene Blue MMx® Modified Release Tablets Administered to Subjects Undergoing Outpatients Colonoscopy

Methylene Blue (MB) is used as vital dye in the colon to facilitate the identification of precancerous lesions. MB-MMX® is an innovative oral colon-release formulation containing 25mg of MB. MB-MMX® has been shown to produce even staining in the colon in a previous dose-ranging study. This study aims to evaluate the polyp and adenoma detection rate in patients (pts) undergoing a full colonoscopy after colonic mucosal staining with MB-MMX® tablets [ MMX® MB chromoendoscopy, MB MMX® -CE].

Colonic diverticulosis is associated with an increased adenoma detection rate in patients undergoing first-time screening colonoscopy

Diverticulosis is a common finding in patients undergoing colonoscopy. The effect of colonic diverticulosis on the colorectal adenoma detection rate (ADR) and other colonoscopy quality indicators remains unclear. To determine if colonic diverticulosis is associated with differences in (1) colorectal ADR and (2) other quality indicators and operating characteristics in patients undergoing first-time screening colonoscopy. Retrospective cohort study conducted at an outpatient surgical center affiliated with an academic medical center. 300 consecutive patients (190 women) with a median age of 57 years (range: 23-70 years) who underwent colonoscopy for various indications were included. 108 (36%) of these 300 patients had diverticulosis found on colonoscopy. 142 (47.3%) of these patients (88 women, median age of 52 years) underwent their first screening colonoscopy. In this population, the frequency of colonic diverticula was 39.2%, and the ADR was 47.5% for patients with diverticulosis and 27.4% for patients without diverticulosis. Multivariate analysis revealed that the presence of diverticulosis had an associated odds ratio of 2.3 (p=0.04) in favor of finding at least one adenoma. No statistically significant differences were found among the rates of total colonoscopy, median scope insertion and withdrawal times, and the amounts of midazolam and fentanyl required for sedation when patients with diverticulosis were compared to those without diverticulosis. Colonic diverticulosis was associated with an increased ADR in patients undergoing first-time screening colonoscopy. The presence of colonic diverticulosis did not adversely affect the cecal intubation rate, scope insertion or withdrawal times, or sedation requirements.

Quality of colonoscopy performance among gastroenterology and surgical trainees: a need for common training standards for all trainees?

Cecal intubation and polyp detection rates are objective measures of colonoscopy performance. Minimum cecal intubation rates greater than 90% have been endorsed by the American Society for Gastrointestinal Endoscopy (ASGE) and the Joint Advisory Group (JAG) UK. Performance data for medical and surgical trainee endoscopists are limited, and we used endoscopy quality parameters to compare these two groups. Retrospective review of all single-endoscopist colonoscopies done by gastroenterology and surgical trainees ("registrars," equivalent to fellows, postgraduate year 5) with more than two years' endoscopy experience, in 2006 and 2007 at a single academic medical center. Completion rates and polyp detection rates for endoscopists performing more than 50 colonoscopies during the study period were audited. Colonoscopy withdrawal time was prospectively observed in a representative subset of 140 patients. Among 3079 audited single-endoscopist colonoscopies, seven gastroenterology trainees performed 1998 procedures and six surgery trainees performed 1081. The crude completion rate was 82%, 84% for gastroenterology trainees and 78% for surgery trainees (P < 0.0001). Adjusted for poor bowel preparation quality and obstructing lesions, the completion rate was 89%; 93% for gastroenterology trainees, and 84% for surgical trainees (P < 0.0001). The polyp detection rate was 19% overall, with 21% and 14% for gastroenterology and surgical trainees, respectively (P < 0.0001). The adenoma detection rate in patients over 50 was 12%; gastroenterology trainees 14% and surgical trainees 9% (P = 0.0065). In the prospectively audited procedures, median withdrawal time was greater in the gastroenterology trainee group and polyp detection rates correlated closely with withdrawal time (r = 0.99). The observed disparity in endoscopic performance between surgical and gastroenterology trainees suggests the need for a combined or unitary approach to endoscopy training for specialist medical and surgical trainees.

Sa1577 Intestinal Cancer Associated With Inflammatory Bowel Disease: Investigation in a Single Hospital in Japan

(P 0.03) in favor of finding at least one polyp and an odds ratio of 2.3 (P 0.03) in favor of finding at least one adenoma (Table 2). When patients with diverticulosis were compared to those without diverticulosis, there were no statistically significant differences in their respective median scope insertion times (6 min vs. 5 min, P 0.27), median withdrawal times (12 min vs. 11 min, P 0.43), or rates of total colonoscopy (100% vs. 97%, P 0.56) on first-time screening exams. Conclusions: Colonic diverticulosis was associated with an increased adenoma detection rate in patients undergoing first-time screening colonoscopy. A biological reason for this association seems implausible. It might be speculated that the presence of diverticulosis prompts an endoscopist to conduct a more careful exam, although the scope withdrawal times measured in this study did not support this presumption. A large prospective study is warranted to confirm these findings.

Endoscopists Trained in the Diagnosis of Nonpolypoid (Flat and Depressed) Colorectal Neoplasms Detect More Adenomatous Lesions

Purpose: Current efforts to prevent colon and rectal cancer focus on the detection and removal of polypoid neoplasm. However, colorectal cancer can also arise from non-polypoid neoplasm, which can be difficult to diagnose. We hypothesized that endoscopists familiar in the detection of non-polypoid colorectal neoplasm (NP-CRN) have increased adenoma detection rates. We studied the adenoma detection rates in patients who had screening colonoscopies performed by endoscopists who were formally trained in the detection of NP-CRN to those who did not. Methods: Comparative study of existing data collected from patients who underwent screening colonoscopy by six attending endoscopists - three of whom trained in the detection of NP-CRN. Data, including endoscopy, post procedure telephone follow-up and pathology reports of eligible patients were then further analyzed. Flat lesions were endoscopically defined by a height of less than half of their diameter. Results: We studied 462 patients - 267 of the patients had screening colonoscopies by endosopists who were trained in the detection of NP-CRN. Patient characteristics were similar between groups. The majority of patients were men with a mean age of 62 ± 6 years (range 40-82). Endoscopists trained in NP-CRN had a higher adenoma detection rate compared to endoscopists without such training (OR 2.52; 95% CI: 1.87-3.41; p < 0.001). They found an average number of 0.75 adenomas per patient compared to 0.55 in the untrained group. The trained endoscopists removed a significantly higher proportion of neoplastic lesions (77%-202/264) than non-trained ones (34%-106 /313) (p < 0.001). NP-CRN lesions were diagnosed more frequently by the trained attendings (OR 2.98; 95% CI: 1.46 to 6.08) than in the untrained group, but accounted for about 33% of the increased number of neoplasms detected. Conclusion: NP-CRN trained endoscopists had significantly higher adenoma detection rates, including both flat and polypoid adenomas - compared to endoscopists without such training, and were more specific in resection of adenomatous over hyperplastic lesions. Training in flat lesion detection has the potential to further improve the quality of colonoscopy.