Recommended Surveillance Intervals Research Articles

Colorectal polyps in young adults: a retrospective review of colonoscopy data from Toowoomba and the Darling Downs.

Polyps are the predominant precursors of colorectal cancer. In the past three decades, the incidence and mortality rates of colorectal cancer have been increasing in adults younger than 50 years. The aim of this clinical audit was to evaluate the prevalence, characteristics and clinical associations of polyps in adults aged 18-49 years presenting to an established private gastroenterology clinic in the Toowoomba Darling Downs region. The audit included data from 353 patient records held by the Toowoomba Gastroenterology Clinic. Data extracted from patient medical records through the Medical Director program software contained structured endoscopy/colonoscopy and histology reports of excised lesions of patients presenting to the clinic. The extract involved identifying all patients aged 18-49 years in the database from January 2019 to March 2022. Patients were screened based on audit inclusion and exclusion criteria. Patients were risk stratified for recommended surveillance intervals as per Australian Clinical Guidelines. Of the sample population, 33.4% were identified with polyps and 22.4% were identified with neoplastic polyps (NPs). A total of 6.7% of 18- to 29-year-old patients were identified with intermediate risk for colorectal cancer (CRC) screening, and 19.8% and 19.3% of 30- to 39-year-old and 40- to 49-year-old patients identified with intermediate or high risk for CRC screening respectively. Increased age, greater size of polyps and surveillance of previous polyps were associated with increased NP prevalence. Data from this audit supported the temporal trend of increasing prevalence of polyps in adults younger than 50 years. Patient cohorts aged 30-39 and 40-49 years may benefit from earlier first colonoscopies. Findings could be the impetus for future research in young adults presenting for colonoscopy.

Single-center experience with intraprocedural cleansing system to improve inadequate bowel preparation during colonoscopy

Inadequate bowel preparation is common despite various preprocedure interventions. There is a need for an intervention at the time of colonoscopy to combat poor preparation. In this retrospective, observational study of 46 patients, we evaluated the clinical efficacy and feasibility of implementing the third generation of the Pure-Vu EVS System, a US Food and Drug Administration-cleared over-the-scope-based intraprocedural cleansing device, into our practice at the Minneapolis VA Medical Center (Minneapolis, Minnesota, United States). To study clinical efficacy, we measured bowel preparation adequacy before and after using the device, as measured by the Boston Bowel Preparation Score, and reviewed colonoscopy surveillance interval recommendations. Technical success and feasibility of using the device were measured by procedure success rates and duration. We found that BBPS scores increased from 4.4 to 7.9 when using the device. Technical success was achieved 78.3% of the time (36/46 cases). Median colonoscopy duration was 46 minutes, although there was a trend toward shorter procedures over time. This is the first clinical evaluation of the third generation of an intraprocedural cleansing device. We found the device efficacious and easy to use with low procedure failure rates, but it does come with a learning curve. We suspect that adoption of this device mutually will benefit patients and health systems with the potential to improve resource utilization.

Effect of an online educational module incorporating real-time feedback on accuracy of polyp sizing in trainees: a randomized controlled trial.

Although polyp size dictates surveillance intervals, endoscopists often estimate polyp size inaccurately. We hypothesized that an intervention providing didactic instruction and real-time feedback could significantly improve polyp size classification. We conducted a multicenter randomized controlled trial to evaluate the impact of different components of an online educational module on polyp sizing. Participants were randomized to control (no video, no feedback), video only, feedback only, or video + feedback. The primary outcome was accuracy of polyp size classification into clinically relevant categories (diminutive [1-5mm], small [6-9mm], large [≥10mm]). Secondary outcomes included accuracy of exact polyp size (inmm), learning curves, and directionality of inaccuracy (over- vs. underestimation). 36 trainees from five training programs provided 1360 polyp size assessments. The feedback only (80.1%, P=0.01) and video + feedback (78.9%, P=0.02) groups had higher accuracy of polyp size classification compared with controls (71.6%). There was no significant difference in accuracy between the video only group (74.4%) and controls (P=0.42). Groups receiving feedback had higher accuracy of exact polyp size (inmm) and higher peak learning curves. Polyps were more likely to be overestimated than underestimated, and 29.3% of size inaccuracies impacted recommended surveillance intervals. Our online educational module significantly improved polyp size classification. Real-time feedback appeared to be a critical component in improving accuracy. This scalable and no-cost educational module could significantly decrease under- and overutilization of colonoscopy, improving patient outcomes while increasing colonoscopy access.

Post-colonoscopy colorectal cancers in a national fecal immunochemical test-based colorectal cancer screening program.

Post-colonoscopy colorectal cancers (PCCRCs) decrease the effect of colorectal cancer (CRC) screening programs. To enable PCCRC incidence reduction in the long-term, we classified PCCRCs diagnosed after colonoscopies performed in a fecal immunochemical test (FIT)-based screening program. PCCRCs diagnosed after colonoscopies performed between 2014-2016 for a positive FIT in the Dutch CRC screening program were included. PCCRCs were categorized according to the World Endoscopy Organization consensus statement into (a) interval PCCRC (diagnosed before the recommended surveillance); (b) non-interval type A (diagnosed at the recommended surveillance interval); (c) non-interval type B (diagnosed after the recommended surveillance interval); or (d) non-interval type C (diagnosed after the intended recommended surveillance interval, with surveillance not implemented owing to co-morbidity). The most probable etiology was determined by root-cause analysis. Tumor stage distributions were compared between categories. 116362 colonoscopies were performed after a positive FIT with 9978 screen-detected CRCs. During follow-up, 432 PCCRCs were diagnosed. The 3-year PCCRC rate was 2.7%. PCCRCs were categorized as interval (53.5%), non-interval type A (14.6%), non-interval type B (30.6%), and non-interval type C (1.4%). The most common etiology for interval PCCRCs was possible missed lesion with adequate examination (73.6%); they were more often diagnosed at an advanced stage (stage III/IV; 53.2%) compared with non-interval type A (15.9%; P<0.001) and non-interval type B (40.9%; P=0.03) PCCRCs. The 3-year PCCRC rate was low in this FIT-based CRC screening program. Approximately half of PCCRCs were interval PCCRCs. These were mostly caused by missed lesions and were diagnosed at a more advanced stage. This emphasizes the importance of high quality colonoscopy with optimal polyp detection.

National adoption of an esophageal cell collection device for Barrett's esophagus surveillance: impact on delay to investigation and pathological findings.

High quality Barrett's esophagus surveillance is crucial to detect early neoplastic changes. An esophageal cell collection device (OCCD) was introduced as a triage tool for Barrett's surveillance. This study aims to evaluate whether the Scottish OCCD program (CytoSCOT) has reduced delays to Barrett's surveillance, and whether delayed surveillance negatively impacts endoscopic pathology. All patients undergoing OCCD testing for Barrett's surveillance across 11 Scottish health boards between 14/9/2020 and 13/9/2022 were identified. Patients were dichotomised into two groups (Year 1 vs. Year 2), with individual records interrogated to record demographics, recommended surveillance interval, time from last endoscopy to OCCD test, and OCCD result. Patients were deemed high-risk if the OCCD demonstrated atypia and/or p53 positivity. Further analysis was performed on patients who underwent endoscopy within 12months of OCCD testing. A total of 3223 OCCD tests were included in the analysis (1478 in Year 1; 1745 in Year 2). In Year 1 versus Year 2, there was a longer median delay to surveillance (9 vs. 5months; P < 0.001), increased proportion of patients with delayed surveillance (72.6% vs. 57.0%; P < 0.001), and more high-risk patients (12.0% vs. 5.3%; P < 0.001). 425/3223 patients (13.2%) were further investigated with upper gastrointestinal endoscopy, 57.9% of which were high-risk. As surveillance delay increased beyond 24months, high-risk patients were significantly more likely to develop dysplasia or malignancy (P = 0.004). Delayed Barrett's esophagus surveillance beyond 24months is associated with increased risk of pre-cancerous pathology. The CytoSCOT program has reduced delays in surveillance, promoting earlier detection of dysplasia and reducing burden on endoscopy services.

Limitations of the Location-Based and Polyp-Based Resect and Discard Strategies

BACKGROUND AND AIMSLocation-based resect and discard (LBRD) and polyp-based resect and discard (PBRD) are 2 recently proposed strategies to minimize the cost of colonoscopy screening and surveillance. Our study applied these strategies to our colonoscopy database retrospectively to determine the applicability of these strategies in our screening and surveillance colonoscopy population. METHODSIn total, 6024 elective screening, surveillance, or diagnostic colonoscopies performed at the University of California, Irvine, were analyzed. We compared the LBRD and PBRD recommendations with longer and shorter 2020 United States Multi-Society Task Forces (USMSTF) surveillance interval recommendations. The primary outcome was the achievement of the 90% agreement threshold set by the American Society of Gastrointestinal Endoscopy Preservation and Incorporation of Valuable Endoscopic Innovations. RESULTSThe LBRD strategy achieved 88.0% and 71.6% concordance with the longer and shorter 2020 USMSTF recommendation guidelines, respectively. The PBRD strategy only applied to 65.4% of procedures, with the remaining procedures still requiring pathologic evaluation. Among the applicable procedures, the PBRD strategy achieved 94.2% and 38.6% concordance with the longer and shorter USMSTF recommendation guidelines, respectively. CONCLUSIONThe PBRD strategy met the 90% preservation and incorporation of valuable endoscopic innovations threshold only when using the longer USMSTF recommendations, but concordance dropped to 38.6% when using the shorter surveillance intervals, which are commonly used in the United States. Although resect and discard may decrease reliance on pathology, these 2 strategies do not achieve the level of concordance required to replace the use of pathology for diminutive polyps in our population.

OGC P31 On the role of Cytosponge for Barrett’s surveillance: assessment of viability and safety of this new technology

Abstract Background Barrett’s Oesophagus is a pre-malignant change where the normal stratified squamous epithelium is replaced by intestinal columnar epithelium. Current guidance produced by the British Society of Gastroenterologists describes 'gold-standard' surveillance as regular upper GI endoscopy with quadrantic biopsies for every 2cm length of Barrett’s oesophagus. The Covid pandemic led to significant delays in the Barrett's surveillance; as a result, many patients have fallen outside their maximum recommended surveillance interval. Cytosponge is a novel cytology sampling device which has a potential role in Barrett's surveillance though its use for this condition remains controversial. Methods All patients who were due for Barrett's surveillance in 2022 were identified and screened for suitability for Cytosponge, instead of endoscopy. Patients who were ineligible, or who declined Cytosponge, were sent for endoscopy. The remaining patients underwent a Cytosponge procedure as their primary Barrett's surveillance modality. Early clinical outcomes, patient satisfaction and cytology results were recorded. All patients have been followed up to determine if they have subsequently required endoscopy or had an early diagnosis of oesphago-gastric cancer. Results 193 patients (77%) were suitable for the Cytosponge test. 175 (90%) did not require endoscopy after Cytosponge. 18 patients (10%) had urgent endoscopy after Cytosponge; 9 patients had atypia on cytological analysis, 3 had aberrant p53 and 4 had dysplasia. Three patients had inadequate cytology. 2 of the patients with dysplasia had high-grade dysplasia confirmed on endoscopy; these were successfully treated with radiofrequency ablation. Median follow-up was 14 months (range, 10-22). No patients have been diagnosed with oesophago-gastric cancer so far; 8 patients (4%) were referred later for anaemia or weight loss. None of these patients had oesophago-gastric cancer. Conclusions These data suggest that Cytosponge can be a valuable first-line tool in surveillance of Barrett’s Oesophagus. Cytology results identified specific patients who required urgent endoscopy. No patients have had an early diagnosis of dysplasia or malignancy after a Cytosponge that was normal or showed intestinal metaplasia alone. Our findings suggest that Cytosponge should be integrated as an adjunct in Barrett’s surveillance, with clear benefits in safer and accurate monitoring of the condition without the risks of endoscopy.

Cancer Biology or Ineffective Surveillance? A Multicentre Retrospective Analysis of Colitis-Associated Post-Colonoscopy Colorectal Cancers.

Inflammatory bowel disease [IBD] is associated with high rates of post-colonoscopy colorectal cancer [PCCRC], but further in-depth qualitative analyses are required to determine whether they result from inadequate surveillance or aggressive IBD cancer evolution. All IBD patients who had a colorectal cancer [CRC] diagnosed between January 2015 and July 2019 and a recent [<4 years] surveillance colonoscopy at one of four English hospital trusts underwent root cause analyses as recommended by the World Endoscopy Organisation to identify plausible PCCRC causative factors. In total, 61% [n = 22/36] of the included IBD CRCs were PCCRCs. They developed in patients with high cancer risk factors [77.8%; n = 28/36] requiring annual surveillance, yet 57.1% [n = 20/35] had inappropriately delayed surveillance. Most PCCRCs developed in situations where [i] an endoscopically unresectable lesion was detected [40.9%; n = 9/22], [ii] there was a deviation from the planned management pathway [40.9%; n = 9/22], such as service-, clinician- or patient-related delays in acting on a detected lesion, or [iii] lesions were potentially missed as they were typically located within areas of active inflammation or post-inflammatory change [36.4%; n = 8/22]. IBD PCCRC prevention will require more proactive strategies to reduce endoscopic inflammatory burden, and to improve lesion optical characterization, adherence to recommended surveillance intervals, and patient acceptance of prophylactic colectomy. However, the significant proportion appearing to originate from non-adenomatous-looking mucosa which fail to yield neoplasia on biopsy yet display aggressive cancer evolution highlights the limitations of current surveillance. Emerging molecular biomarkers may play a role in enhancing cancer risk stratification in future clinical practice.

Significant Reduction in the Diagnosis of Barrett's Esophagus and Related Dysplasia During the COVID-19 Pandemic.

The coronavirus disease 19 (COVID-19) pandemic disrupted endoscopy practices, creating unprecedented decreases in cancer screening and surveillance services. We aimed to assess the impact of the pandemic on the proportion of patients diagnosed with Barrett's esophagus (BE) and BE-related dysplasia and adherence to established quality indicators. Data from all esophagogastroduodenoscopies in the GI Quality Improvement Consortium, a national repository of matched endoscopy and pathology data, were analyzed from January 2018 to December 2022. Four cohorts were created based on procedure date and COVID-19 data: pre-pandemic (January 2018 to February 2020), pandemic-phase I (March 2020 to July 2020), pandemic-phase II (August 2020 to May 2021), and pandemic-phase III (June 2021 to December 2022). Observed and expected number of BE and BE-related dysplasia cases per month and adherence to the Seattle biopsy protocol and recommended surveillance intervals for nondysplastic BE (NDBE) were evaluated. Among 2,446,857 esophagogastroduodenoscopies performed during the study period, 104,124 (4.3%) had pathology-confirmed BE. The histologic distribution was 87.4% NDBE, 1.8% low-grade dysplasia, 2.4% indefinite for dysplasia, and 1.4% high-grade dysplasia. The number of monthly BE (-47.9% pandemic-phase I, -21.5% pandemic-phase II, and -19.0% pandemic-phase III) and BE-related dysplasia (high-grade dysplasia: 41.2%, -27.7%, and -19.0%; low-grade dysplasia: 49.1%, -35.3%, and -26.5%; any dysplasia: 46.7%, -32.3%, and -27.9%) diagnoses were significantly reduced during the pandemic phases compared with pre-pandemic data. Adherence rates to the Seattle protocol and recommended surveillance intervals for NDBE did not decline during the pandemic. There was a significant decline in the number of BE and BE-related dysplasia diagnoses during the COVID-19 pandemic, with an approximately 50% reduction in the number of cases of dysplasia diagnosed in the early pandemic. The absence of a compensatory increase in diagnoses in the pandemic-phase II and III periods may result in deleterious downstream effects on esophageal adenocarcinoma morbidity and mortality.

Adherence to guideline recommendations for Barrett's esophagus (BE) surveillance endoscopies: Effects of dedicated BE endoscopy lists.

Background and study aims For non-dysplastic Barrett's Esophagus (BE) patients, guidelines recommend endoscopic surveillance every 3 to 5 years with four-quadrant random biopsies every 2 cm of BE length. Adherence to these guidelines is low in clinical practice. Pooling BE surveillance endoscopies on dedicated endoscopy lists performed by dedicated endoscopists could possibly enhance guideline adherence, detection of visible lesions, and dysplasia detection rates (DDRs). Patients and methods Data were used from the ACID-study (Netherlands Trial Registry NL8214), a prospective trial of BE surveillance in the Netherlands. BE patients with known or previously treated dysplasia were excluded. Guideline adherence, detection of visible lesions, and DDRs were compared for patients on dedicated and general endoscopy lists. Results A total of 1,244 patients were included, 318 on dedicated lists and 926 on general lists. Endoscopies on dedicated lists showed significantly higher adherence to the random biopsy protocol (85% vs. 66%, P <0.01) and recommended surveillance intervals (60% vs. 47%, P <0.01) compared to general lists. Detection of visible lesions (8.8% vs. 8.1%, P =0.79) and DDRs were not significantly different (6.9% and 6.6%, P =0.94). None (0.0%) of the patients scheduled on dedicated lists and 10 (1.1%) on general lists were diagnosed with esophageal adenocarcinoma ( P =0.07). In multivariable analysis, dedicated lists were significantly associated with biopsy protocol adherence and adherence to surveillance interval recommendations with odds ratios of 4.45 (95% confidence interval [CI] 2.07-9.57) and 1.64 (95% CI 1.03-2.61), respectively. Conclusions Dedicated endoscopy lists are associated with better adherence to the random biopsy protocol and surveillance interval recommendations.

S1687 De-Implementation of Outdated Colonoscopy Surveillance Interval Recommendations Among Patients With Low-Risk Adenomas (DESIRE)

S1687 De-Implementation of Outdated Colonoscopy Surveillance Interval Recommendations Among Patients With Low-Risk Adenomas (DESIRE)

Validation of the Modified Location-based Resect-and-discard Strategy Requiring Pathology Examination of Sigmoid Diminutive Polyps.

Recently, the location-based resect-and-discard (LBRD) strategy, which does not depend on optical diagnosis, was developed and demonstrated different surveillance interval agreement with the pathology-based reference in several researches. We aimed to evaluate the performance of LBRD in our first-time colonoscopy cohort, and improve the LBRD. The first-time colonoscopy with complete pathologic information were enrolled. The accuracy of LBRD strategy applied in diminutive polyps in different colonic segments was used as indicator to develop modified LBRD (mLBRD) strategy. Surveillance interval agreement with pathology-based reference was compared between LBRD and mLBRD. The ≥ 90% agreement with pathology was used as benchmark. The polyps in sigmoid colon were significantly associated with higher proportion of neoplastic compared with polyps in rectum. The accuracy of LBRD applied in polyps in sigmoid colon were only 53.5%, which was significantly lower than that applied in polyps in other colonic segments. Thus, we hypothesized that mLBRD requiring pathology examination of diminutive polyps in sigmoid colon was more efficient in clinical use. The mLBRD significantly outperformed LBRD in surveillance interval agreement with pathology-based reference (90.2% vs. 83.4%, P <0.001), had lower proportion of patients assigned a longer surveillance interval (3.6% vs. 10.5%, P <0.001) and reached the benchmark, although the proportion of patients with an immediate surveillance interval recommendations and pathology examination avoided decreased. The mLBRD, but not LBRD, achieved sufficient surveillance interval agreement with pathology-based surveillance interval assignment and reduced over 30% of pathology examinations.

Adherence to Surveillance Endoscopies Posteradication of Barrett's Esophagus With High-grade Dysplasia or Carcinoma In Situ.

We aimed to evaluate factors associated with patient adherence to recommended surveillance guidelines during the first 3 years after endoscopic eradication of Barrett's esophagus (BE) with high-grade dysplasia (HGD) or T1a carcinoma in situ (CIS) and the relationship between adherence and detection of recurrence. While surveillance endoscopies after treatment of BE with HGD or T1a CIS are an important component of therapy, it is unclear whether these high-risk patients are adhering to recommended surveillance guidelines. A total of 123 BE patients who underwent radiofrequency ablation±endoscopic mucosal resection for biopsy-proven HGD, or CIS between January 2010 and November 2018 underwent retrospective review for adherence to surveillance guidelines, patient factors related to adherence, and recurrence of dysplasia or CIS at 12, 24, and 36 months. Of 123 BE patients (89 HGD and 34 CIS), adherence during the first year following treatment was 26.97% for HGD patients and 41.18% for CIS patients, with increasing adherence rates in subsequent years. Patients who received 3 to 4 surveillance endoscopies in the first year posttreatment had significantly higher rates of recurrence detection than patients who received 0 to 2 surveillance endoscopies over this interval ( P =0.01). No patient factors were found to impact adherence significantly. Adherence to recommended surveillance intervals after endoscopic treatment of BE with HGD or CIS is low, with poor adherence during the first year associated with decreased detection of recurrence. Future studies are needed to evaluate risk factors and develop a potential intervention for poor adherence in this high-risk population.

Colorectal Neoplasia 10 Years or More Following Negative Colonoscopy: Time to Extend Recommended Surveillance Intervals?

Heisser T, Kretschmann J, Hagen B, et al. Prevalence of colorectal neoplasia 10 or more years after a negative screening colonoscopy in 120 000 repeated screening colonoscopies. JAMA Intern Med 2023;183:183–190.

Clinical variation in surveillance and management of Barrett’s esophagus: A cross-sectional study of gastroenterologists and gastrointestinal surgeons

Appropriate surveillance and treatment of Barrett's esophagus (BE) is vital to prevent disease progression and decrease esophageal adenocarcinoma (EAC)-related mortality. We sought to determine the variation in BE care and identify improvement opportunities. 275 physicians (113 general gastroenterologists, 128 interventional gastroenterologists, 34 gastrointestinal surgeons) cared for 3 simulated patients, one each from 3 BE clinical scenarios: non-dysplastic BE (NDBE), BE indefinite for dysplasia (IND), and BE with low grade dysplasia (LGD), and care scores were measured against societal guidelines. Overall quality-of-care scores ranged from 17% to 85% with mean of 47.9% ± 11.8% for NDBE, 50.8% ± 11.7% for IND, and 52.7% ± 12.2% for LGD. Participants appropriately determined risk of progression 20.3% of the time: 14.4% for NDBE cases, 19.9% for LGD cases, and 26.8% for IND cases (P = .001). Treatment and follow-up care scores averaged 12.9% ± 17.5% overall. For the LGD cases, guideline-recommended twice-daily PPI treatment was ordered only 24.7% of the time. Guideline-based follow-up endoscopic surveillance was done in only 27.7% of NDBE cases and 32.7% of IND cases. For the LGD cases, 45.4% ordered endoscopic eradication therapy while 25.1% chose annual endoscopic surveillance. Finally, participants provided counseling on lifestyle modifications in just 20% of cases. Overall care of patients diagnosed with BE varied widely and showed room for improvement. Specific opportunities for improvement were adherence to guideline recommended surveillance intervals, patient counseling, and treatment selection for LGD. Physicians would potentially benefit from additional BE education, endoscopic advances, and better methods for risk stratification.

Wide Variability in Dysplasia Detection Rate and Adherence to Seattle Protocol and Surveillance Recommendations in Barrett's Esophagus: A Population-Based Analysis Using the GIQuIC National Quality Benchmarking Registry.

Variability in adherence rates to the Seattle protocol and to surveillance interval recommendations, established quality indicators (QIs) in Barrett's esophagus (BE), is unknown. We evaluated endoscopist and site-based adherence rates to these QIs from January 2018 to May 2021 using the GI Quality Improvement Consortium national registry with matched endoscopy and pathology data. Across 153 practices with 572 endoscopists performing 20,155 endoscopies, adherence to the Seattle protocol varied by endoscopists (median 93.8%, IQR 18.9%) and by site (median 90.0%, IQR 20.1%). Adherence to appropriate surveillance intervals for nondysplastic BE also varied by endoscopist (median 82.4%, IQR 36.3%) and site (median 77.2%, IQR 29.8%). The overall dysplasia detection rate was 3.1% and varied among endoscopists and sites. These US population-based results can serve as a benchmark for quality initiatives and intervention trials aimed at improving outcomes for patients with BE.

S245 Risk Factors for 5-Year Post-Colonoscopy Colorectal Cancers (PCCRCs)

Introduction: 3-10% of CRCs are PCCRCs, which are CRCs identified after a colonoscopy (CY) that does not find CRC. Risk factors for PCCRCs have been little studied. The study aim was to identify risk factors for PCCRCs at 3 years (PCCRC-3y) based on polypectomy of ≥ 1 neoplastic polyps at index CY. Methods: We assembled a cohort of 50 to 85 year-old Veterans with newly diagnosed CRC from 1/1/2003 to 12/31/2013, examining prior exposure to CY. Those whose CY occurred ≤ 6 months prior to CRC diagnosis with no other CY within the previous 36 months were categorized as having detected CRC (DCRC). Those whose CY occurred 6-36 months prior to CRC diagnosis were categorized as PCCRC-3y. We conducted 2 nested case-control studies (CCS) based on whether polypectomy of neoplastic polyps was performed during index CY, and compared demographics, clinical features, and CY-specific factors (e.g., prep quality, endoscopist training, VA- vs non-VA CY, and recommended surveillance interval) between PCCRC cases and DCRC controls who were matched for age and facility in a 1:2 ratio. Univariable and multivariable logistic regression identified factors independently associated with PCCRC, reported as odds ratios (OR) and 95% CIs. Results: There were 29,877 patients with CRC, with 1785 (6.0%) classified as PCCRC. From this dataset, we identified 402 cases and 804 matched controls w/o polypectomy and 404 cases and 808 controls with polypectomy, with cases and controls comparable demographically. Factors independently associated with PCCRC in the no polypectomy CCS were: Charlson score (OR=1.10; CI, 1.00-1.21); BMI ≥ 30 kg/M2 (OR=1.66; CI, 1.16-2.39); and recommended surveillance interval either < 5 years (OR=4.67; CI, 3.30-6.66) or missing (OR=3.00; CI, 2.17-4.14), c-statistic = 0.70. When the two surveillance variables were removed from the model, good or excellent prep quality was protective (OR=0.64; CI, 0.46-0.78), c-statistic=0.61. In the polypectomy CCS, the factors were: non-VA CY (OR=2.97; CI, 1.11-8.21); non-GI endoscopist (OR=1.64; CI, 1.16-2.33); advanced adenoma (OR=2.02; CI, 1.54-2.65); ≥ 2 proximal polyps (OR=1.43; CI, 1.09-1.87) and recommended follow-up < 1 year (OR=3.38; CI, 2.40-4.80), c-statistic of 0.71. Conclusion: Several factors are associated with PCCRC-3yr, some of which are modifiable, and the most important of which is recommended surveillance interval. These factors may be useful for tailoring surveillance and as targets for quality improvement.

S400 A Cost Utility Model Supports Changes in Post-Treatment Surveillance Associated With the 2022 American College of Gastroenterology Guidelines

Introduction: Radiofrequency ablation is a safe and effective treatment for neoplastic Barrett’s esophagus (BE), but surveillance after endoscopic eradication has only been studied observationally without any studies of this disease’s natural history. Recent natural history modeling work has allowed qualified estimation of a natural history scenario. We sought to apply our multi-state model of post-ablation natural history to study the cost effectiveness of surveillance after endoscopic eradication of neoplastic BE. Methods: We constructed a microsimulation cost-utility model of endoscopic surveillance after complete eradication of intestinal metaplasia (CEIM) with intervals as recommended by the 2022 American College of Gastroenterology BE guideline. A cohort of participants were modeled after the United States (US) Radiofrequency Ablation cohort in terms of demographics, worst prior histologic grade, and pre-treatment BE segment length. Transition probabilities for the natural history were estimates from published multi-state models. The model was Markov generalized to allow differing rates of progression based on BE characteristics as covariates to the multi-state model and for other-cause mortality to depend on age. There were states for: no recurrence, recurrence with various histologic grades, ablative re-treatment, endoscopic mucosal resection, invasive adenocarcinoma, and death. We considered a willingness-to-pay threshold of 100,000 2017 US dollars ($) per quality-adjusted life year (QALY). Model parameters and their sources are described in the Table. Results: In the base case scenario of the model, surveillance and re-treatment decreased progression to invasive esophageal adenocarcinoma at ten years by 1.2% in LGD and 13.0% in HGD/IMC (Figure). Compared to the natural history scenario, the incremental cost effectiveness ratio for surveillance at ten years was $79,125 for LGD and $10,952 for HGD/IMC. Conclusion: In the base case scenario of this cost-utility model, newly recommended surveillance intervals were highly cost effective for HGD/IMC and approached the margins of cost-effectiveness for LGD in a microsimulation cost-utility model. This supports the new guideline recommendation to decrease the frequency of post-treatment surveillance of HGD/IMC and LGD. While development of the model requires probabilistic sensitivity analysis and calibration, the model has the potential to inform the health economics of clinical processes after CEIM. Table 1. - Microsimulation model parameters in the base case scenario and their sources. Model variable Base case value Reference/details Structural model assumptions Model cycle length 3 months Model time horizon 10 years Model starting year 2017 For other-cause mortality and inflation adjustment Other cause mortality Population 2020 Social Security actuarial cohort life Tables Time for resection 1 cycle Resection for all recurrent HGD or IMC Resection success rate 100% Simplifying assumption Time for ablation 1 cycle Repeated until successful Discounting of costs/utilities 3% Per year Probabilities per cycle from the literature Death from invasive adenocarcinoma 7.63% SEER 5-Year Relative Survival Rates 2012-2018* Complete eradication of intestinal metaplasia after recurrence 57.7% Guthikonda et al., The American Journal of Gastroenterology, 2017 Cancer progression from recurrence 0.1625% Guthikonda et al., The American Journal of Gastroenterology, 2017 Utilities per cycle from the literature Surveillance after CEIM 97% Boger et al., Alimentary Pharmacology and Therapeutics, 2010 Retreatment endoscopy 94% Boger et al., Alimentary Pharmacology and Therapeutics, 2010 Esophageal adenocarcinoma 96% Boger et al., Alimentary Pharmacology and Therapeutics, 2010 Costs per cycle from the literature Surveillance endoscopy $1,019 Inadomi et al., Gastroenterology, 2009† Cost of cancer care $13,532 Inadomi et al., Gastroenterology, 2009† Cost of ablation re-treatment $4,317 Inadomi et al., Gastroenterology, 2009† Assumed half cost of initial treatment Cost of resection re-treatment $934 Filby et al., Journal of Comparative Effectiveness Research, 2017 ** *Assumes cumulative incidence = 1 – e^(-incidence x time).†Assuming 17.7% inflation.**Assumes 133% exchange rate with the British Pound. Figure 1.: Model state occupancy by months after complete eradication of intestinal metaplasia.

Appropriateness of fecal immunochemical testing utilization for colorectal cancer screening at an academic center

Fecal immunochemical testing (FIT) has become the most utilized test for colorectal cancer (CRC) screening. This retrospective quality assurance report analyzed data for 411 patients from one academic center in Central New York who underwent FIT between September 2015 and September 2016. All 67 positive tests and 344 of 952 negative tests were analyzed. Subjects from the FIT-negative “control group” were chosen at random. The mean age was 67 years and the male/female distribution was 391/20, with differences between the FIT-positive and -negative groups. FIT was inappropriately used in 210 (51%) of the 411 patients. The most common reasons for inappropriate FIT use were a documented refusal of colonoscopy (39.60% of inappropriate use), FIT occurring within the recommended surveillance interval from previous colonoscopy (27.98%), and a Charlson Co-Morbidity Index score ≥5 (22.87%). Other reasons were a history of adenoma (9.25%), family history of CRC/high-risk adenoma <60 years of age (5.84%), active/overt gastrointestinal bleed (4.87%), history of CRC (1.46%), and history of inflammatory bowel disease (1.46%). The results of this study show that FIT is being utilized inappropriately about 50% of the time.

Non-optical polyp-based resect and discard strategy: A prospective clinical study.

BACKGROUNDPost-polypectomy surveillance intervals are currently determined based on pathology results.AIMTo evaluate a polyp-based resect and discard model that assigns surveillance intervals based solely on polyp number and size. METHODSPatients undergoing elective colonoscopies at the Montreal University Medical Center were enrolled prospectively. The polyp-based strategy was used to assign the next surveillance interval using polyp size and number. Surveillance intervals were also assigned using optical diagnosis for small polyps (< 10 mm). The primary outcome was surveillance interval agreement between the polyp-based model, optical diagnosis, and the pathology-based reference standard using the 2020 United States Multi-Society Task Force guidelines. Secondary outcomes included the proportion of reduction in required histopathology evaluations and proportion of immediate post-colonoscopy recommendations provided to patients. RESULTSOf 944 patients (mean age 62.6 years, 49.3% male, 933 polyps) were enrolled. The surveillance interval agreement for the polyp-based strategy was 98.0% [95% confidence interval (CI): 0.97–0.99] compared with pathology-based assignment. Optical diagnosis-based intervals achieved 95.8% (95%CI: 0.94–0.97) agreement with pathology. When using the polyp-based strategy and optical diagnosis, the need for pathology assessment was reduced by 87.8% and 70.6%, respectively. The polyp-based strategy provided 93.7% of patients with immediate surveillance interval recommendations vs 76.1% for optical diagnosis.CONCLUSIONThe polyp-based strategy achieved almost perfect surveillance interval agreement compared with pathology-based assignments, significantly reduced the number of required pathology evaluations, and provided most patients with immediate surveillance interval recommendations.