Serrated Polyp Detection Rate Research Articles

Correlation between proximal serrated polyp detection and clinically significant serrated polyps: inter-endoscopist variability.

The adenoma detection rate (ADR) is the most important quality indicator for the prevention of colorectal cancer but serrated polyps are also precursor lesions of the disease. The aim of our study was to compare the detection rate of proximal serrated polyps (PSPs) and that of clinically significant serrated polyps (CSSPs) between endoscopists and analyze the relation of those parameters to the ADR. An observational, prospective, cross-sectional study was conducted on all patients that underwent colonoscopy at the Policlínico Peruano Japonés within the time frame of July 2015 and August 2016. The ADR and PSP and CSSP detection rates between endoscopists were compared through multivariate logistic regression and the association between those parameters was calculated through the Pearson correlation coefficient. The study included 15 endoscopists and 1,378 colonoscopies. The PSP detection rate ranged from 1.8-17% between endoscopists and had an almost perfect correlation with the CSSP detection rate (p = 0.922), as well as strongly correlating with the ADR (p = 0.769). There was great variability in the PSP detection rate between endoscopists. It also had an almost perfect correlation with the CSSP detection rate and strongly correlated with the ADR. Those results suggest a high CSSP miss rate at endoscopy and a low PSP detection rate.

Latest Generation High-Definition Colonoscopy Increases Adenoma Detection Rate by Trainee Endoscopists.

Adenoma detection rate (ADR) is an important quality indicator of colonoscopy. High-definition (HD) colonoscopy has been reported to increase ADR compared to standard-definition (SD) colonoscopy. Although there are few reports comparing the latest generation and the previous generation of HD colonoscopy equipment, there are reports that the latest generation colonoscopy equipment improves ADR. However, there are no reports on the impact of the latest generation HD colonoscopy on the ADR of trainee endoscopists. The aim of this study was to investigate whether the latest generation HD colonoscopy increases the ADR of trainee endoscopists compared with the previous generation HD colonoscopy. We conducted a retrospective review of medical records of patients aged 40-79years old, who underwent screening or surveillance colonoscopy performed by nine gastroenterology fellows at Dong-A University Hospital from March 2019 to February 2020. We calculated the overall ratios of the ADR: the ADRs of the group using the older generation HD colonoscopy equipment and the group using the latest HD colonoscopy equipment. Polyp detection rate (PDR), sessile serrated polyp detection rate (SSPDR), and advanced neoplasia detection rate (ANDR) were calculated for each group. Factors related to adenoma detection were identified using logistic regression analysis. Altogether, 2189 patients were included in the study (the older HD colonoscopy group comprising 1183 and the latest HD colonoscopy group comprising 1006). We found that PDR (45.98 vs. 51.69%, p = 0.008) and ADR (35.67 vs. 40.85%, p = 0.013) were significantly higher in the latest generation HD colonoscopy group. The generational differences were not statistically significant for SSPDR (1.94 vs. 2.78%, p = 0.195) or ANDR (4.65 vs. 4.97%, p = 0.726). In the multivariate regression analysis, age, male sex, the latest generation HD colonoscopy, and long withdrawal time were the most significant factors affecting adenoma detection. The latest generation HD colonoscopy improved PDR and ADR by trainee endoscopists. These findings suggest that latest generation, higher-resolution colonoscopy equipment can improve the quality of colonoscopy for less experienced endoscopists.

Do Water-aided Techniques Improve Serrated Polyp Detection Rate During Colonoscopy?: A Systematic Review With Meta-Analysis.

The utility of water-aided techniques (WT): water exchange (WE) and water immersion (WI) have been studied extensively in the literature for improving colonoscopy outcome metrics such as adenoma detection rate. Serrated polyps owing to their location and appearance have a high miss rate. The authors performed a systematic review and meta-analysis of studies comparing WT with the standard gas-assisted (GA) method to determine if there was any impact on serrated polyp detection rate (SPDR) and sessile serrated polyp detection rate. The following databases were queried for this systematic review: Medline, EMBASE, Cochrane Library, CINAHL, and Web of Sciences. The authors only included randomized controlled trials (RCTs). The primary outcome was SPDR and secondary outcomes were sessile serrated polyp detection rate and cecal intubation rate. Risk ratios (RRs) were calculated for each outcome. A P-value <0.05 was considered to be statistically significant. A total of 4 RCTs (5 arms) with 5306 patients (2571 in the GA group and 2735 in the WT group) were included. The SPDR was significantly increased for the WT group compared with GA (6.1% vs. 3.8%; RR, 1.63; 95% confidence interval, 1.24-2.13; P<0.001; I2=22.7%). A subgroup analysis for WE technique also demonstrated improved SPDR compared with the GA method (4.9% vs. 3.2%; RR, 1.57; 95% confidence interval, 1.15-2.14; P=0.004; I2=6.1%). WT, particularly, the WE method results in improved SPDR. This technique should be encouraged in a clinical setting to detect these polyps to prevent interval colorectal cancer.

Mo1708 ASSESSMENT OF QUALITY INDICATORS IN COLONOSCOPY TRAINING SERVICE IN BRAZI

The aim of this study is to assess quality criteria in colonoscopy in the examinations of patients of the public health system, performed by the students of our unit. We retrospectively analyzed 1943 colonoscopies and its anatomopathological reports, performed from February 2018 to February 2019 by students of our endoscopy unit . Data were collected such as gender, age, body mass index, examination indication, family history, quality of preparation, withdraw time, polyp detection rate, adenoma detection rates, serrated polyp detection rates, and malignant neoplasms, as well as data on immediate complications. In the 1943 exams analyzed, we found that 1345 (69.22%) was female. The average age was 59 years. The main indication was prevention (36.64%). The caecum arrival rate was 98.9% in patients without obstructive lesions or inadequate preparation. The quality of the preparation was proper in 97% of the cases. The withdraw time was 10.54 minutes in examinations without procedures. Polyps resection rate was 40.92% and overall adenoma detection rate of adenomas was 30.83%. Nine malignant neoplasms were found (2.16%). Men had 1.3 times the prevalence of adenoma compared with women (P < 0.001: 95% CI: 1.1-1.5). Patients over 60 years old have 3.8 times the prevalence of adenomas than those under 40 years old (P < 0.001; 95% CI: 2.2-6.5). Patients aged 40 to 60 years have almost 3 times the prevalence of adenomas than patients under 40 years (P < 0.001; 95% CI: 1.6-5.0). There was 1 case of postpoiypectomy bleeding. The data obtained are compatible with the international quality criteria. The adenoma detection rate was higher in men. The detection of adenomas increased with age, highlighting the significant increase from 40 years. We emphasize the importance that colonoscopy training services measure their adenoma detection rates to achieve adequate levels of quality.

Mo1695 WATER EXCHANGE (WE) INCREASES SESSILE SERRATED POLYP DETECTION RATE (SSPDR) COMPARED WITH AIR (AI) OR CARBON DIOXIDE (CO2) INSUFFLATION - POOLED DATA ANALYSIS OF FOUR RECENT REPORTS

A net-work meta-analysis (GIE. 2018;88:589) showed water exchange (WE) provided the highest adenoma detection rate (ADR). The impact on sessile serrated polyp detection rate (SSPDR) was not addressed. SSP have increased malignant potential (Curr Treat Options Gastroenterol. 2015;13:156). They have subtle appearance (AJG. 2012;107:1315). They cluster in the proximal colon (61%) (Arch Pathol Lab Med. 2015;139:388) co-localizing with interval cancers (64% to 68%) (Gastro. 2014;146:950; Cancer. 2012;118:3044). The finding of SSPs was mentioned in several RCTs comparing WE with air (AI) or carbon dioxide (CO2) insufflation. We test the hypothesis that compared with air (AI) or carbon dioxide (CO2) insufflation, water exchange (WE) could enhance the real-time detection of SSP. The aim is to assess the impact of WE (vs. AI or CO2) on SSPDR. Four reports with data on SSP and WE vs. AI or CO2 insufflation were identified. Demographic, procedural and SSP data were extracted, pooled and analyzed. By pooling the data in four RCTs the pitfall of type II error due to small sample size could be avoided. Table 1 summarizes the salient demographic and procedural features. Table 2 shows that the pooled SSPDR of WE (8.0%) was significantly higher than that of air or CO2 insufflation combined (5.0%) (p=0.0017, Fisher exact test). The combined data showed WE significantly increased SSPDR by 3%. With an estimated 19 million colonoscopies in the US in 2018 (https://idataresearch.com/an-astounding-19-million-colonoscopies-are-performed-annually-in-the-united-states/), 3.0% of 19 million (570,000) is clinically meaningful. The improved outcomes of increased SSPDR add value to WE colonoscopy. The improved value appears to justify consideration to incorporate WE into colorectal cancer prevention programs.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

Mo1646 IS ENDOSCOPIST PERFORMANCE STABLE ACROSS COLONOSCOPY INDICATIONS AND TYPES OF COLORECTAL CANCER (CRC) PRECURSORS? IMPLICATIONS FOR QUALITY ASSURANCE

The adenoma detection rate (ADR) during first-time screening colonoscopy is inversely correlated with the interval CRC rate, and it has therefore become the key colonoscopy quality performance metric. However, first-time screening is only one of the colonoscopy indications related to CRC prevention and control, a large procedure volume is needed for a precise ADR estimate, and ADR does not measure advanced or sessile serrated polyp (SSP) detection. To explore correlations across detection rates for any and advanced adenomatous polyps and SSPs, and the range of colonoscopy indications related to CRC control. The Stanford Colonoscopy Quality Assurance Program database was queried for Oct,2017–Aug,2019. The database relies on standardized procedure report documentation and standardized pathology result letters. Data for 10 endoscopists whose metrics were not reliable because of known documentation deficiencies were excluded. Correlations (Pearson correlation coefficient, r) were explored between 1) adenoma detection rates during colonoscopies for first-time screening and colonoscopies for: a) screening not first-time, b) post-polypectomy surveillance, and c) family history of CRC; and 2) detection rates at colonoscopies for all these indications combined between any adenoma and: a) SSP, b) advanced adenoma, and c) advanced SSP. A minimum of 10 procedures per category were required for inclusion in a particular analysis. The Table shows the correlation coefficients and p-values. Adenoma detection at colonoscopy for first-time screening was not significantly correlated with adenoma detection at colonoscopy for screening not first-time, surveillance or family history of CRC (Table). When combining colonoscopies with any of the four indications, adenoma detection was correlated with SSP detection (r=0.65, p<0.0001, Figure), but not advanced adenoma or advanced SSP detection (Table). In the current era, ADR over broadened indications beyond first-time screening may also reflect SSP detection, but not necessarily lesion detection during screening not first-time, surveillance or screening for family history of CRC, or advanced lesion detection. The contributions of chance, patient characteristics, or endoscopist performance to these results remain to be determined, including whether endoscopist performance is affected by particular vigilance to ADR during first-time screening. More comprehensive monitoring across the range of colonoscopy indications and lesion types could improve the assessment of endoscopist performance, and possibly improve CRC control efforts.Significant correlation between adenoma and sessile serrated polyp detection rates during colonoscopy for four screening and surveillance indicationsView Large Image Figure ViewerDownload Hi-res image Download (PPT)

Are adenoma and serrated polyp detection rates correlated with endoscopists’ sensitivity of optical diagnosis?

We performed an exploratory post-hoc analysis of the DISCOUNT-2 study, including complete colonoscopies after a positive fecal immunochemical test (FIT) performed by endoscopists who performed ≥ 50 colonoscopies. The correlations between the ADR, PSPDR, and the sensitivity of optical diagnosis were calculated using Pearson's rho correlation coefficient. 24 endoscopists performed ≥ 50 colonoscopies, resulting in a total of 2889 colonoscopies. The overall ADR was 84.5 % (range 71.4 % - 95.3 %) and overall PSPDR was 13.7 % (4.3 % - 29.0 %). The sensitivity of optical diagnosis for adenomas and serrated polyps were 94.5 % (83.3 % - 100 %) and 74.0 % (37.5 % - 94.1 %), respectively. No correlation could be demonstrated between the ADR and the sensitivity of optical diagnosis for adenomas (-0.20; P = 0.35) or between the PSPDR and the sensitivity of optical diagnosis for serrated polyps (-0.12; P = 0.57). In a homogeneous FIT-positive population, no correlation between the ADR, PSPDR, and the sensitivity of optical diagnosis for adenomas and serrated polyps could be demonstrated. These exploratory results suggest that lesion detection and differentiation require different endoscopic skills. Further prospective studies are needed; until then, monitoring of both performance indicators is important to secure optimal efficacy of FIT-based colorectal cancer screening.

A149 COMPARING THE REAL-WORLD EFFECTIVENESS OF 4L VERSUS 2L SPLIT COLONOSCOPY PREPARATIONS: PRELIMINARY DATA OF A SINGLE CENTRE EXPERIENCE THROUGH THE BRITISH COLUMBIA COLONOSCOPY SCREENING PROGRAM

Abstract Background The British Columbia Colon Screening Program (CSP) is a population-based program offering biennial fecal immunochemical test (FIT) to individuals age 50–74 years with follow-up colonoscopy for a positive FIT as well as individuals with a personal history of neoplastic polyps or a high risk family history of colorectal cancer. Over 20,000 colonoscopies are performed annually. In December 2018, program colonoscopists in Vancouver, Canada agreed to switch from a 2L polyethylene glycol (PEG) preparation to a 4L PEG preparation after studies suggested superiority of the higher volume preparation in achieving adequate bowel cleansing and improving adenoma detection rates (ADR). High quality bowel cleansing is critical to minimize repeat procedures and maximize neoplasia detection. Aims To compare the quality of bowel preparation and neoplasia detection rates using the 4L high volume split preparation (HVSP) versus the 2L low volume split preparation (LVSP) in patients undergoing colonoscopy in the BC CSP. Methods A retrospective review of consecutive patients undergoing colonoscopy through the CSP at St. Paul’s Hospital from Dec 2017-Apr 2018 and Dec 2018-Apr 2019 was conducted. Inclusion criteria included: age 50–74, patients undergoing colonoscopy for any reason through the BC CSP. Variables collected included: patient demographics, bowel preparation qualty and pathologic findings. ADR and sessile serrated polyp detection rate (SSDR) were analyzed. Results 462 colonoscopies were included, 280 in the LVSP group and 182 in the HVSP group. 8/280 (2.9%) had poor bowel preparation in the LVSP group, while 10/182 (5.5%) had poor bowel preparation in the HVSP group. The ADR and SSDR were 53.6% in LVSP vs. 50.0% in HVSP and 8.2% in LVSP vs. 8.8% in HVSP, respectively. Conclusions In this preliminary evaluation, the high volume PEG-based split preparation did not reduce the proportion of inadequate bowel preparations. Further evaluation of a larger number of colonoscopies is planned. Funding Agencies None

Simple proxies for detection of clinically significant serrated polyps and data for their benchmarks.

Serrated polyp detection rate (SDR) is a potential quality indicator for preventing colorectal cancer associated with the serrated pathway. Using clinically significant SDR (CSSDR) has been suggested based on clinically significant serrated polyp's ability to be colorectal cancer precursors. Correlations between CSSDR and simpler SDRs, other than proximal SDR, have not yet been studied. We aimed to investigate which simpler SDR indicator is most relevant to CSSDR or adenoma detection rate (ADR) and provide benchmark data. We analyzed 26627 colonoscopies performed by 30 endoscopists. Clinically significant serrated polyps were defined as any sessile serrated adenoma/polyp or traditional serrated adenoma, hyperplastic polyps≥5mm in the proximal colon, or hyperplastic polyps≥10mm anywhere in the colon. Correlation of CSSDR and ADR with other simple SDRs, SDR-pathology (sessile serrated adenoma/polyp or traditional serrated adenoma), SDR-size (≥10mm), and SDR-location (proximal location) was analyzed using Pearson's correlation test and Steiger's z-test. The CSSDR was 1.7% to 13.2% (mean=6.1%). The correlation coefficient of CSSDR/SDR-size was 0.91 (P<0.01), which was higher than that of CSSDR/SDR-location (0.64, P<0.01) (0.91 vs 0.61, P<0.01). The correlation coefficient of ADR/CSSDR and ADR/SDR-location was 0.41 (P<0.01) and 0.81 (P<0.01), respectively. For ADR≥25%, endoscopists' median screening CSSDR was 5.4%, while SDR-location and SDR-size were 10.9% and 2.2%, respectively. Large SDR could be a simple proxy for CSSDR, in addition to proximal SDR. Large SDR and proximal SDR benchmarks of 2.2% and 10.9% may guide adequate serrated polyp detection with uniform definitions and simpler calculations.

Author commentary on Jagpal S. Klair et al.

Jagpal S. Klair et al. Serrated polyp detection rate and advanced adenoma detection rate from a US multicenter cohort

Serrated polyp detection rate and advanced adenoma detection rate from a US multicenter cohort.

Interval colorectal cancers may be associated with a low serrated polyp detection rate (SDR) and advanced adenoma detection rate (AADR). We aimed to determine the SDR and AADR for endoscopists in a United States multicenter cohort. We included average-risk screening colonoscopies from five medical centers in the United States. Endoscopists with data on at least 100 average-risk screening colonoscopies were included. We calculated median SDR and AADR for endoscopists with adequate adenoma detection rates (ADRs) > 25 %. We analyzed the relationship between ADR and SDR, and between ADR and AADR using nonparametric Spearman correlation coefficients, scatter plots, and linear regression. We included 3513 screening colonoscopies performed by 26 gastroenterologists. The mean age of patients was 56.8 years (SD 7.4) and 1585 (45 %) were male. All but one endoscopist had an ADR above 25 %. There was a significant positive but modest correlation between ADR and SDR (rho = 0.67, P < 0.01), and between ADR and AADR (rho = 0.56, P < 0.01). For endoscopists with an adequate ADR, median (interquartile range) ADR was 43 % (32.0 % - 48.6 %), median SDR was 8.4 % (7.3 % - 11.4 %), and median AADR was 9.3 % (6.4 % - 12.6 %). A significant percentage of endoscopists have either a low SDR or low AADR despite an adequate ADR, justifying the need for separate SDR and AADR benchmarks. Based on our multicenter cohort, endoscopists with adequate ADRs had a median SDR and median AADR of about 8 % and 9 %, respectively.

333 Identifying the Link Between Adenoma and Serrated Polyp Detection Rates and the Effect of Withdrawal Time on Both During Screening Colonoscopies

INTRODUCTION: Adenoma detection rate (ADR) and its surrogate marker, mean withdrawal time (WT) of ≥ 6 min, is the current golden metric for colonoscopy quality. Serrated polyp detection rate (SPDR) is also an important marker for CRC. Longer WTs are linked with higher ADRs. We aim to assess if there is a correlation between SPDR and ADR, and if the same link exists between WTs and SPDR, as it exists for WT on ADR. METHODS: Screening colonoscopies between 2012 and 2017 were evaluated. Endoscopists with &lt; 40 colonoscopies and procedures with polyps &gt;6 mm, and/or WTs &gt;30 min were excluded. Data was grouped into fellow (FG) and attending (AG) groups. The bivariate association of SPDR and ADR was calculated by correlation coefficients. Statistical analysis was performed using chi-squared tests, two-sample t-tests, and ANOVA t-testing. RESULTS: A total of 5951 procedures performed by 51 fellows and 13 attendings were assessed. The MWT was 15.4 min, SD 4.72, average total procedure time (TT) was 28.3 min, and average ADR was 40%. WT had a strong positive correlation with ADR and TT. The average SPDR was 0.1, SD 0.056. SPDR had a positive correlation with WT and ADR. There were significant differences between FG and AG in ADR, WT, TT and in regression models between the two for TT. There was no difference in the mean SPDR between groups. SPDR had a strong positive correlation with ADR and WT in the AG. There was no significant difference between bowel prep vs. SPDR between groups. CONCLUSION: Our study demonstrates a strong linear relationship between WT, ADR and TT. While FG have a higher ADR compared with AG at the cost of a longer WT, how much ADR changes as WT increases is not significant. AG and FG had similar SPDRs, however, only for AG were SPDR positively correlated with longer WTs and higher ADRs. We postulate that given the increased technical difficulty in detecting sessile polyps, AG are better equipped to improve SPDRs with increased WT. Bowel prep scores had no effect on SPDR, explained by exclusion criteria including only fully completed colonoscopies, and therefore subpar prep patients were likely pre-excluded. Our study highlights the importance of expertise and training in the identification of sessile polyps, the association between high ADR and SPDR, and the positive effect of WT on SPDR. Kahi et al., identified variability in SPDR ranging from 1% to 18%, compared with much less variability seen in ADRs. As a result, our findings are worthy of validation in larger multiple center studies.

315 Can Adenoma Detection Rates Predict a Benchmark for Serrated Polyp and Advanced Adenoma Detection Rates in a Diverse Urban Population?

INTRODUCTION: Adenoma detection rate (ADR) benchmark of &gt;25% has been shown to reduce interval colorectal cancer (CRC). Serrated polyp detection rate (SDR) and advanced adenoma detection rate (AADR) can also serve as additional benchmarks to reduce interval CRC, although a standardized benchmark for AADR and SDR doesn’t exist. Recent studies have shown correlation between ADR, SDR and AADR, but in a homogenous patient population. Our study evaluated the correlation between ADR, SDR and AADR and approximated a benchmark for SDR and AADR in a diverse urban population, while attempting to identify any patient variables affecting detection rates. METHODS: We reviewed screening colonoscopies performed at our midwest urban, safety-net health care system over a period of one year (2017). We calculated ADR, SDR and AADR for individual providers and established correlation using non-parametric Spearman correlation coefficients between the 3 entities. Logistic regression analysis was used to calculate predictors of adenomas, advanced adenomas and serrated polyps. RESULTS: Of the 3000 colonoscopies reviewed, 1488 were screening colonoscopies performed by 9 experienced staff gastroenterologists. The patient population included 48% African-Americans, 42% Caucasians, and 10% others. Median (Interquartile range) ADR of all providers was 42.5 (27-61), SDR 8.4 (3.6-23), and AADR was 2.9 (0.6-4.8). All providers had an overall ADR above 25%. There was a weak positive correlation for ADR and SDR (rho = 0.13), and ADR and AADR (rho = 0.13). Logistic regression analysis identified male gender (P &lt; 0.01) and body mass index (P = 0.02) as predictors of adenomas, while longer withdrawal time was a significant predictor for all types of polyps. We did not find statistical significance for gender or body mass index and SDR. CONCLUSION: Based on our study, previously suggested benchmark SDR of 7% seems appropriate. Our AADR of 2.9 was lower than suggested AADR of &gt;6%. Additionally, a weak positive correlation was noted between ADR and SDR, and ADR with AADR although the patient population was heterogeneous and diverse making the results more generalizable for the real world.

234 Higher Serrated Detection Rate Is Associated With Lower Risk for Post-Colonoscopy Colorectal Cancer

INTRODUCTION: The serrated pathway may account for a significant proportion of colorectal cancer (CRC). Achieving adequate serrated polyp detection rates (SDR) may reduce the incidence of post colonoscopy CRC (PCCRC). We used data from the New Hampshire Colonoscopy Registry (NHCR) to determine if exams performed by endoscopists who have a clinically significant serrated polyp detection rate (CSSDR) of 7% or greater, proposed by Anderson/Butterly (GIE 2017), had a reduced incidence of PCCRC. In addition, we compared CSSDR to the adenoma detection rate (ADR), the currently used benchmark. METHODS: We defined PCCRC as any CRC diagnosed between 6 and 36 months after an exam with an adenoma on index and between 6 and 60 months following a normal exam. Exclusion criteria were any CRC diagnosed at index or within 3 months, incomplete exams, IBD, and genetic syndromes. Clinically significant serrated polyps (CSSP) were defined as any sessile serrated polyp, traditional serrated adenoma, serrated polyp &gt;1 cm anywhere in the colon and any serrated polyp &gt;5 mm proximal to the sigmoid. CSSDR was defined as number of screening exams with at least one CSSP divided by all screening exams. The exposure variable was a CSSDR of 7% and adenoma detection rate of 25%. Cox regression was used to model the risk of PCCRC in terms of the covariates at index exam. Covariates were age, BMI, smoking, index findings (large serrated polyp, advanced adenoma or any adenoma), followup time (months), bowel prep quality, having more than 1 surveillance exam and family history of CRC. We also compared receiver operating characteristics (ROC) for CSSDR 7% to an ADR 25% using probabilities derived from a logistic regression analysis. RESULTS: In our sample (142,950 index exams) 75 CRCs were diagnosed during the 6–60 month period (45 CRCs diagnosed between 6–36 months) after the index exam. The hazard ratio (HR) for CSSDR of 7% (HR = 0.37 95% CI 0.17–0.83) was similar to that for an ADR of 25% (HR = 0.45 95% 0.23–0.89) (Table 1). The ROCs were similar for CSSDR and ADR and the combination of the 2 rates did not alter the ROC (Table 2). CONCLUSION: Having an exam performed by an endoscopist with a CSSDR of 7% or greater was associated with a decrease incidence of PCCRC (HR = 0.37). The performance of CSSDR and ADR for PCCRC incidence were similar. These data suggest that a CSSDR of 7% or greater may be associated with lower PCCRC rates. However, it may not add an information to that provided by the current primary colonoscopy benchmark, ADR.

261 Sessile Serrated Polyp Detection Rate as a Screening Colonoscopy Quality Metric

INTRODUCTION: Adenoma detection rate (ADR) is an established colonoscopy quality metric primarily used to prevent interval colorectal cancer (CRC). Likewise, higher sessile serrated polyp detection rates (SSPDR) were linked to reduced interval CRC. Recently, some studies suggested the use SSPDR as a quality indicator with proposed benchmarks mimicking that seen in ADR where 25% of all procedures should yield adenomas (20% for females and 30% for males). We aimed in our study to examine the utility of SSPDR as a quality metric for screening colonoscopies with proposed new target benchmarks. METHODS: A retrospective review of all screening colonoscopies in patients ≥50 years of age performed at our tertiary center between 2012 and 2014 was done. Average risk patients who had a complete colonoscopy with excellent, good, or adequate bowel preparation were included. Overall and segment specific ADR and SSPDR were calculated and compared using t-tests. Data is presented as mean ± standard deviation or frequency (%). The adjusted R-Squared statistic (R2) was used to test the correlation variability. The P-value corresponds to the correlation between ADR and SSPDR. All analyses were done using SAS (version 9. 4, The SAS Institute, Cary, NC) and a P-value &lt; 0. 05 was considered statistically significant. RESULTS: A total of 4151 patients were included in the analysis. Average patient age was 60.0 ± 7.7 years and 53.2% were females. Colonoscopies were performed by 54 (64.3%) gastroenterologists and 30 (35.7%) non-gastroenterologists (General Surgeons = 9; Colorectal Surgeons = 21) (Table 1). Overall ADR was 26.4 ± 11.0, overall SSPDR was 19.3 ± 11.4. Overall SSPDR that corresponds to a predicted ADR of 25% was 16% (adjusted R2 = 0.16, P-value &lt; 0.001). SSPDR in females that corresponds to an ADR of 20% was 10% (adjusted R2 = 0.11, P-value = 0.001) (Figure 1). These findings reflect a significant but poor correlation between ADR and SSPDR. CONCLUSION: Based on a large screening colonoscopy registry-based analysis, our results support the use of SSPDR as an ancillary rather than independent colonoscopy quality metric. The current study suggests a cut-off values of 16% for overall SSPDR and 10% for the female papulation. SSPDR above these values may be congruous with adequate serrated polyp detection rates. Further multicenter studies are needed to validate our findings.

264 The Differences in Prevalence, Distribution, and Detection Rates of Colonic Polyps Between Genders

INTRODUCTION: Gender disparities in colorectal cancer (CRC) incidence and mortality are well recognized in the literature with polyp characteristics and location being amongst some of the most important factors contributing to these disparities. Prior studies have shown an increased prevalence of proximal adenomas and CRC in women. We aimed in this study to compare the distribution and the prevalence of colonic polyps between both genders, as well as evaluating gender-specific lesion detection rates. METHODS: A retrospective review of all screening colonoscopies in patients ≥50 years of age performed at our center between 2012 and 2014 was done. Average risk patients who had a complete colonoscopy with excellent, good and fair bowel preparation were included. Overall, gender-specific, and segment-specific adenoma detection rates (ADR), sessile serrated polyp detection rates (SSPDR) and polypectomy rates (PR) were calculated and compared using t-tests. Proximal colon was defined as the cecum, ascending, and the transverse colon. RESULTS: A total of 4151 patients were included in the analysis. Average patient age was 60.0 ± 7.7 years and 53.2% were females. A total of 652 (15.7%) had excellent preparation, 2675 (64.4%) had good preparation, while 824 (19.9%) had fair preparation (Table 1). Of the 3476 polyps found, 1660 (47%) polyps were found in the proximal colon. Generally, males had more polyps and adenomas all throughout the colon (Table 2). Compared to males, females had less proximal polyps per patient (0.35 ± 0.24 vs. 0.50 ± 0.33; P &lt; 0.001), less proximal adenomas per patient (0.22 ± 0.18 vs. 0.35 ± 0.26, P &lt; 0.001), and less overall large adenomas (&gt;1 cm) per patient (0.05 ± 0.07 vs. 0.09 ± 0.13, P &lt; 0.008). In males, endoscopists had better overall ADR (32.7 ± 14.7 vs. 22.0 ± 12.7, P &lt; 0.001), PR (51.9 ± 17.9 vs. 40.3 ± 18.8, P &lt; 0.001), and SSPDR (22.6 ± 15.7 vs. 16.6 ± 13.7, P &lt; 0.001) (Table 3). CONCLUSION: Our study demonstrates a significant difference in polyp distribution based on patient sex. This is contradictory to what has previously been reported in the literature with more proximal polyps noted in female patients. We believe the advancement in colonoscopy techniques and training in addition to the increased awareness of female sex association with right-sided tumors contributed to this topographic distribution shift of colonic polyps. Although the involved endoscopists met the recommended national ADR benchmarks, women had lower ADR reflecting the differences in the adenoma prevalence in these populations.

239 Detection Rate of Serrated Adenomas in the Screening Colonoscopy Population

INTRODUCTION: Colorectal cancers arise from 3 distinct pathways: the adenoma to carcinoma pathway, the Lynch syndrome pathway, and the serrated pathway. The serrated pathway is characterized by neoplastic transformation of serrated polyps, which are classified into hyperplastic polyps (HP), sessile serrated adenomas (SSA) and traditional serrated adenomas (TSA). HPs distal to descending colon have no malignant potential, while SSA &amp; TSA are precancerous lesions. SSA are the major precursor lesions responsible of cancer via serrated pathway. SSA are difficult to differentiate histologically from HPs in the proximal colon. Recent studies have shown SSAs to be more common than previously believed. Our study purpose is to determine the prevalence of SSAs, variability amongst endoscopists in detecting serrated adenomas, and the identification of significant risk factors. METHODS: Patients undergoing screening colonoscopy were enrolled into this prospective cross-sectional study conducted at a tertiary community teaching hospital and an outpatient endoscopy unit. Screening colonoscopy was defined as the first colonoscopy performed in an asymptomatic patient without risk factors between the age of 50 and 80. Patients reported as having poor bowel preparation were excluded from the study. Statistical analysis was conducted to determine the overall detection rate of serrated adenomas and assess the variability among 6 endoscopists. RESULTS: Of the 263 screening colonoscopies, the serrated adenoma detection rate was 12.2% (95% CI 8.2–16.2%) with a wide range of variability amongst the 6 endoscopists from 3.4–15%. The total serrated polyp detection rate, which includes SSA, TSA and proximal HPs, was 13.7% (95% CI 9.5–17.9%) with a range of 10.2–17.5% amongst endoscopist. The adenoma detection rate for the endoscopists was 46.4% (95% CI 40.4–52.4%). Study results revealed serrated polyps have a significant association with Caucasians (P = 0.002), while adenomatous polyps are significantly associated with males (P = 0.001) and current smokers (P = 0.01). CONCLUSION: The increasing prevalence of SSA found in recent studies seems directly related to improving histologic distinction between SSA and HPs. Despite this improvement, the reported prevalence is still highly variable. Our study found that by using a total serrated polyp detection rate we were able to reduce variability amongst endoscopists, and a significant association between Caucasians and development of serrated polyps.

Difference in Physician- and Patient-Dependent Factors Contributing to Adenoma Detection Rate and Serrated Polyp Detection Rate.

Adenoma detection rate (ADR) is correlated with the risk of interval colorectal cancer and is considered as a quality benchmark for colonoscopy. Serrated polyp detection rate (SPDR) might be a more stringent indicator of quality in polyp detection. To evaluate in a 2-year monocentric observational study patient-dependent and endoscopist-dependent factors influencing ADR and SPDR in daily practice. We determined ADR and SPDR. We collected patient-dependent factors and endoscopist-dependent factors. Links between these data and detection rates were assessed by uni- and multivariate analysis. A total of 11682 colonoscopies were performed (female: 54.3%; male: 45.7%; median age 58) by 30 endoscopists (female: 9; male: 21). ADR and SPDR were 29.2% and 8%, respectively. In multivariate analysis, ADR was associated with patient-dependent factors: age (OR 1.044, CI 95% 1.040-1.048), male gender (OR 1.7, CI 95% 1.56-1.85), personal history of polyp/cancer (OR 1.53, CI 95% 1.3-1.9), and positive fecal immunochemical test (OR 2.47, CI 95% 2.0-3.1). In multivariate analysis, SPDR was associated with withdrawal time (OR 1.25, CI 95% 1.17-1.32), low volume activity (OR 1.3, CI 95% 1.1-1.52), and personal history of polyp/cancer (OR 1.61, CI 95% 1.15-2.25). In this large series of routine colonoscopies, we found that ADR was mainly driven by patient-dependent conditions, i.e., age, male gender, colonoscopy indication for positive FIT, and a personal history of polyp or cancer. In contrast, SPDR was mainly related to endoscopist-dependent factor, i.e., withdrawal time and low volume activity.

Impact of a ring-fitted cap on insertion time and adenoma detection: a randomized controlled trial

Devices for flattening colon folds can improve polyp detection at colonoscopy. However, there are few data on the endoscopic ring-fitted cap (EndoRings; EndoAid, Caesarea, Israel). We sought to compare adenoma detection with EndoRings with that of standard high-definition colonoscopy. This was a single-center, randomized controlled trial of 562 patients (284 randomized to EndoRings and 278 to standard colonoscopy) at 2 outpatient endoscopy units in the Indiana University Hospital system. Adenoma detection was the primary outcome measured as adenoma detection rate (ADR) and adenomas per colonoscopy (APC). We also compared sessile serrated polyp detection rate, insertion times, withdrawal times, and ease of passage through the sigmoid colon. EndoRings was superior to standard colonoscopy in terms of APC (1.46 vs 1.06, P= .025), but there were no statistically significant differences in ADR or sessile serrated polyp detection rate. Mean withdrawal time (in patients with no polyps) was shorter and insertion time (all patients) was longer in the EndoRings arm by 1.8 minutes and 0.75 minutes, respectively. One provider had significantly higher detection with Endo-Rings and contributed substantially to the overall results. EndoRings can increase adenoma detection without a significant increase in procedure time, but the effect varies between operators. The use of EndoRings slows colonoscope insertion. (Clinical trial registration number: NCT03418662.).

Sa1042 MULTI-TARGET STOOL DNA TESTING ENRICHES DETECTION OF COLORECTAL NEOPLASIA BY COLONOSCOPY BUT YIELD IS INFLUENCED BY BASELINE POLYP DETECTION RATES

Adenomatous polyp detection rates (ADR) are inversely correlated with the incidence of post-colonoscopy colorectal cancers. To measure colonoscopy quality, a minimum ADR of 25% and sessile serrated polyp detection rate (SDR) of 5% have been proposed as quality standards. Colonoscopy appears to have higher ADR after a positive (+) MT-sDNA among providers aware of stool test results versus those blinded in a clinical trial. The interaction between endoscopists’ baseline polyp detection rates and MT-sDNA yield in practice has not been explored.