Average-risk Screening Research Articles

Abstract A027: Systematic review of real-world adherence to blood-based laboratory tests for average-risk disease screening: potential implications for emerging colorectal cancer screening modalities

Abstract Introduction: Blood-based tests represent a compelling option for early detection and management of cancers and other chronic diseases. While blood-based tests may offer potential to increase patient engagement, the assumption of greater adherence in clinical practice requires further evaluation. This systematic review aimed to evaluate the real-world adherence to established blood-based tests for commonly recommended screening indications, to better inform expectations for proposed application to average-risk colorectal cancer (CRC) screening. Methods: A systematic search of PubMed, Embase, and citations was performed to identify literature published from 2010 to 2023. Studies examined adherence to routine blood-based laboratory tests with a Grade A or B recommendation per the United States Preventive Services Task Force (USPSTF) for diabetes, dyslipidemia, human immunodeficiency virus (HIV), and hepatitis C virus (HCV) in an average-risk patient population were included. In addition, prostate-specific antigen (PSA) testing adherence for prostate cancer screening (Grade-C USPSTF recommendation), the only commonly accessible blood-based single-cancer screening test for average-risk adults, was also included. Studies without venipuncture-derived blood were excluded. Results: Of 53,067 articles screened, 69 were included in the analysis. Overall, adherence rates of blood-based tests were highly variable, with median values (interquartile range, IQR) of 66.3% (11.8%), 67.8% (18.0%), 34% (28.7%), and 36.8% (30%) for diabetes, dyslipidemia, HCV, and HIV, respectively. PSA testing adherence was 37.2% (18.4%). Beyond disease type, adherence varied by study design, data source, patient characteristics, clinical setting, and study country. Information and selection bias were the most common risks of bias. Conclusions: Based on data from this comprehensive systematic review, real-world adherence to currently recommended, blood-based screening strategies is suboptimal. Future research is needed to identify the extent to which these data are generalizable to blood-based CRC screening, and to determine if/how this candidate strategy would impact clinical, economic, and health equity outcomes. Citation Format: Quang A. Le, Takako Kiener, Heather A. Johnson, Rukaiyya S. Khan, Joyce Kong, Kevin H. Li, Gina Thompson, A. Burak Ozbay, Mallik Greene, Paul J. Limburg, A. Mark Fendrick, John B. Kisiel, Derek W. Ebner. Systematic review of real-world adherence to blood-based laboratory tests for average-risk disease screening: potential implications for emerging colorectal cancer screening modalities [abstract]. In: Proceedings of the AACR Special Conference: Liquid Biopsy: From Discovery to Clinical Implementation; 2024 Nov 13-16; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(21_Suppl):Abstract nr A027.

Age Matters: Adenoma Detection Rates in Average-risk Screening Patients Aged 45 to 49 Compared With Those Aged 50 to 54.

This study aims to address gaps in medical knowledge by determining whether adenoma detection rate (ADR) in average-risk screening patients aged 45 to 49 is equivalent to screening patients aged 50 to 54. Current guidelines recommend initiating colon cancer screening at age 45, yet our understanding of the effects of ADR in average-risk individuals among 45- to 49-year-olds is still limited. A retrospective analysis was conducted on records of average-risk screening colonoscopies performed on patients aged 45 to 54 from January 2018 to August 2022. Exclusions were prior diagnoses of colorectal cancer or adenomatous polyps, inflammatory bowel disease, personal or family history of genetic cancer syndromes, incomplete colonoscopy, and inadequate bowel preparation. The primary outcome was ADR in the age 45 to 49 group compared with the age 50 to 54 group. Of the 3199 average-risk screening colonoscopies performed, 879 and 2116 patients were included in the age 45 to 49 and 50 to 54 groups, respectively. Both groups were predominantly female, White ethnicity, never smokers, and obese. ADR was found to be 27% in the age 45 to 49 group compared with 34% in the age 50 to 54 group (odds ratio 0.70, 90% CI: 0.60-0.83, P -value for equivalence=0.81 w/ margin 0.77 to 1.30). The study did not demonstrate equivalent ADR between the 2 age groups, with ADR being substantially lower in the age 45 to 49 group (27% vs. 34%). Despite this, the ADR in the 45 to 49 age range surpasses the established benchmark of 25%, supporting the decision to lower the screening age to 45 years. Ongoing national monitoring is essential to comprehensively evaluate the impact of these updated guidelines.

13-year colorectal cancer risk after lower-quality, higher-quality and no screening colonoscopy: a cohort study

ObjectiveA lower-quality colonoscopy has been shown to be less effective in reducing colorectal cancer (CRC) incidence than a higher-quality colonoscopy, but the comparison with no screening colonoscopy is lacking. We aimed to compare the 13-year risk of developing CRC between persons with I) a higher-quality screening colonoscopy, II) a lower-quality screening colonoscopy and III) without a screening colonoscopy. Study Design and SettingA healthcare database (∼20% of the German population) was used to emulate a target trial with three arms: Higher-quality screening colonoscopy (higherQualSC) vs. lower-quality screening colonoscopy (lowerQualSC) vs. no screening colonoscopy (noSC) at baseline. The quality of screening colonoscopy was categorized based on the polyp detection rate of the examining physician (cut-off: 21.8%). We included persons aged 55 to 69 years at average CRC risk and CRC screening naïve at baseline. We estimated adjusted cumulative CRC incidence over 13 years of follow-up. ResultsThe higherQualSC arm comprised 142,960 persons, the lowerQualSC arm 62,338 persons and the noSC arm 124,040 persons. The adjusted 13-year CRC risk was 1.77% in the higherQualSC arm, 2.09% in the lowerQualSC arm and 2.74% in the noSC arm. Compared to the noSC arm, the adjusted relative risk was 0.76 (95% CI: 0.70–0.84) in the lowerQualSC arm and 0.65 (95% CI: 0.60–0.69) in the higherQualSC arm. ConclusionOur study shows that a lower-quality screening colonoscopy is also effective in reducing CRC incidence compared to no screening colonoscopy. However, the effect is about one third less than that of a higher-quality screening colonoscopy.

Impact of Time Period and Birth Cohort on the Trend of Advanced Neoplasm Prevalence in the 40–49 Average-Risk Screening Population

Early-onset colorectal cancer (CRC) is increasing globally. While the United States have lowered the age of initiation of screening to 45, other countries still start screening at age 50. In Taiwan, the incidence of CRC has declined in 55-74 year-olds after the initiation of screening, but still increased in those 50-54, potentially due to rising precancerous lesion incidence in 40-49 year-olds. This study aimed to explore the chronological trend of the prevalence of colorectal advanced neoplasms (AN) in the screening population aged 40-54. We retrospectively analyzed a screening colonoscopy cohort for prevalence of AN in average-risk subjects aged 40-54 from 2003 to 2019. Logistic regression was used to distinguish cohort effect from time-period effect on the prevalence of AN. In total, 27,805 subjects (52.1% male) men were enrolled. There were notable increases in prevalence of AN in all three age groups during the 17-year span, but these were more rapid in age 40-44 (0.99% to 3.22%) and 45-49 (2.50% to 4.19%). Age 50-54 had higher risk of AN [aOR=1.62(1.19-2.19)] in 2003-2008 but not in later periods [2009-2014: aOR=1.08(0.83-1.41)] and [2015-2019: aOR=0.76(0.56-1.03)] when compared with age 45-49. The prevalence of AN in age 40-54 increased in the Taiwanese population, with a later birth cohort having a higher prevalence of AN. However, the prevalence of AN in age 45-49 increased more remarkably and approximated that in age 50-54, which may justify earlier initiation of CRC screening at age 45.

Real-world multi-target stool DNA longitudinal adherence for colorectal cancer re-screening in a large, national population.

e15633 Background: Colorectal cancer (CRC) is the fourth most diagnosed cancer, as well as the second leading cause of cancer death in the United States – with an estimated 152,810 diagnoses and 53,010 fatal cases in 2024. Regular screening and early detection can reduce CRC incidence and improve overall survival; however, recent national survey data (2021) demonstrate that only 59% of the US screen-eligible population (≥ age 45) is up to date. Home-based, non-invasive CRC screening test options, such as the multi-target stool DNA (mt-sDNA) test, have the potential to improve patient outcomes and overcome CRC screening adherence barriers at multiple levels. Given that the recommended interval for mt-sDNA is three years, a better understanding of use in repeat users is warranted. We evaluated the effective rescreen rate of previous mt-sDNA test users. Methods: In this retrospective cohort study, we included patients between the ages of 45 and 75 years who were shipped an mt-sDNA test kit between January 1st – December 31st, 2023, and had previously completed mt-sDNA screening with a negative result > 2.5 years prior. Our primary variable of interest was mt-sDNA completion rate on repeat testing, defined as kit receipt with a valid result within 120 days of the shipment date. Regression analysis was performed to determine baseline characteristics associated with repeat test completion rate. Results: During the analysis period, a total of 481,748 patients who met the inclusion criteria received an mt-sDNA kit. The majority of the cohort was female (61.4%) and between the ages of 65-75 years (50.9%). Overall repeat test completion rate was 83.6%, with the average time to kit return being 18.9 days. Completion rates were similar between males (83.8%) and females (83.6%), and patients receiving included navigation support via mobile phones demonstrated the shortest average time to kit return (18.7 days). Completion rates increased concordantly with patient age: 81.6%, (45-49 years), 82.2% (50-64 years), and 85% (65-75 years). For first-time rescreen participants (2nd lifetime mt-sDNA test), the completion rate was 83.1%. For second-time rescreen participants (3rd lifetime mt-sDNA test), the completion rate was even higher at 93.6%. Logistic regression analyses revealed that patients re-screening for a second-time were three times more likely to return the mt-sDNA kit for CRC screening (OR = 3.118; p < 0.001). Conclusions: Data from this large, retrospective cohort study revealed that repeat CRC screening with the mt-sDNA test is associated with high adherence to triennial follow-up among participants. suggesting a high-level of perceived patient confidence in repeat performance of the mt-sDNA test. These novel data provide relevant insights regarding strong patient willingness to continue with home-based, non-invasive mt-sDNA testing over multiple cycles of average-risk CRC screening.

Overall Polyp Detection Rate as a Surrogate Measure for Screening Efficacy Independent of Histopathology: Evidence from National Endoscopy Database.

Adenoma detection rate (ADR) is challenging to measure, given its dependency on pathology reporting. Polyp detection rate (PDR) (percentage of screening colonoscopies detecting a polyp) is a proposed alternative to overcome this issue. Overall PDR from all colonoscopies is a relatively novel concept, with no large-scale studies comparing overall PDR with screening-only PDR. The aim of the study was to compare PDR from screening, surveillance, and diagnostic indications with overall PDR and evaluate any correlation between individual endoscopist PDR by indication to determine if overall PDR can be a valuable surrogate for screening PDR. Our study analyzed a prospectively collected national endoscopy database maintained by the National Institute of Health from 2009 to 2014. Out of 354,505 colonoscopies performed between 2009-2014, 298,920 (n = 110,794 average-risk screening, n = 83,556 average-risk surveillance, n = 104,770 diagnostic) met inclusion criteria. The median screening PDR was 25.45 (IQR 13.15-39.60), comparable with the median overall PDR of 24.01 (IQR 11.46-35.86, p = 0.21). Median surveillance PDR was higher at 33.73 (IQR 16.92-47.01), and median diagnostic PDR was lower at 19.35 (IQR 9.66-29.17), compared with median overall PDR 24.01 (IQR 11.46-35.86; p < 0.01). The overall PDR showed excellent concordance with screening, surveillance, and diagnostic PDR (r > 0.85, p < 0.01, 2-tailed). The overall PDR is a reliable and pragmatic surrogate for screening PDR and can be measured in real time, irrespective of colonoscopy indication.

National Trends in the Incidence of Sporadic Malignant Colorectal Polyps in Young Patients (20-49 Years): An 18-Year SEER Database Analysis.

Background and Objectives: Conflicting guidelines exist for initiating average-risk colorectal cancer screening at the age of 45 years. The United States Preventive Services Task Force (USPSTF) changed its guidelines in 2021 to recommend initiating screening at 45 years due to an increasing incidence of young-onset colorectal cancer. However, the American College of Physicians (ACP) recently recommended not screening average-risk individuals between 45 and 49 years old. We aim to study the national trends in the incidence of sporadic malignant polyps (SMP) in patients from 20 to 49 years old. Materials and Methods: We analyzed the Surveillance, Epidemiology, and End Results database (2000-2017) on patients aged 20-49 years who underwent diagnostic colonoscopy with at least a single malignant sporadic colorectal polyp. Results: Of the 10,742 patients diagnosed with SMP, 42.9% were female. The mean age of incidence was 43.07 years (42.91-43.23, 95% CI). Approximately 50% of malignant polyps were diagnosed between 45 and 49 years of age, followed by 25-30% between 40 and 45. There was an upward trend in malignant polyps, with a decreased incidence of malignant villous adenomas and a rise in malignant adenomas and tubulovillous adenomas. Conclusions: Our findings suggest that almost half of the SMPs under 50 years occurred in individuals under age 45, younger than the current screening threshold recommended by the ACP. There has been an upward trend in malignant polyps in the last two decades. This reflects changes in tumor biology, and necessitates further research and support in the USPSTF guidelines to start screening at the age of 45 years.

Commentary: Liquid Biopsy for Average-Risk Colorectal Cancer Screening

Commentary: Liquid Biopsy for Average-Risk Colorectal Cancer Screening

Post-polypectomy surveillance: follow-up recommendations from the Alberta Colorectal Cancer Screening Program.

In 2013, the Alberta Colorectal Cancer Screening Program (ACRCSP) initially published recommendations for post-colonoscopy follow-up and polypectomy. Over time, emerging evidence and evolving surveillance guidelines from various expert groups necessitated a comprehensive review to align with the healthcare landscape in Alberta. To accomplish this, an expert panel was convened. Using the Agree II tool, we identified high-quality Clinical Practice Guidelines that were relevant to the Alberta medical context. Recommendations from these guidelines were adapted to fit the specific needs of Alberta. Recognizing inconsistencies and gaps within the existing guidelines, we conducted targeted literature reviews to ensure a comprehensive and evidence-based approach to our recommendations. Our revised recommendations build upon the assumption that a high-quality index colonoscopy has been performed at baseline. They are intended to enhance the quality of care and reduce unnecessary procedures. As well, they align with the growing consensus in the scientific literature that individuals with low-risk tubular adenomas may not require aggressive colonoscopy surveillance. The updated Alberta recommendations aim to provide clear recommendations for practicing endoscopists, referring physicians, and their patients. They address crucial questions such as determining which patients should commence surveillance via colonoscopy and which individuals should return to average-risk screening using the fecal immunochemical test (FIT). Additionally, our recommendations outline the appropriate surveillance intervals for those requiring continued monitoring.

A Cell-free DNA Blood-Based Test for Colorectal Cancer Screening

BackgroundColorectal cancer is the third most diagnosed cancer in adults in the United States. Early detection could prevent more than 90% of colorectal cancer–related deaths, yet more than one third of the screening-eligible population is not up to date with screening despite multiple available tests. A blood-based test has the potential to improve screening adherence, detect colorectal cancer earlier, and reduce colorectal cancer–related mortality.MethodsWe assessed the performance characteristics of a cell-free DNA (cfDNA) blood-based test in a population eligible for colorectal cancer screening. The coprimary outcomes were sensitivity for colorectal cancer and specificity for advanced neoplasia (colorectal cancer or advanced precancerous lesions) relative to screening colonoscopy. The secondary outcome was sensitivity to detect advanced precancerous lesions.ResultsThe clinical validation cohort included 10,258 persons, 7861 of whom met eligibility criteria and were evaluable. A total of 83.1% of the participants with colorectal cancer detected by colonoscopy had a positive cfDNA test and 16.9% had a negative test, which indicates a sensitivity of the cfDNA test for detection of colorectal cancer of 83.1% (95% confidence interval [CI], 72.2 to 90.3). Sensitivity for stage I, II, or III colorectal cancer was 87.5% (95% CI, 75.3 to 94.1), and sensitivity for advanced precancerous lesions was 13.2% (95% CI, 11.3 to 15.3). A total of 89.6% of the participants without any advanced colorectal neoplasia (colorectal cancer or advanced precancerous lesions) identified on colonoscopy had a negative cfDNA blood-based test, whereas 10.4% had a positive cfDNA blood-based test, which indicates a specificity for any advanced neoplasia of 89.6% (95% CI, 88.8 to 90.3). Specificity for negative colonoscopy (no colorectal cancer, advanced precancerous lesions, or nonadvanced precancerous lesions) was 89.9% (95% CI, 89.0 to 90.7).ConclusionsIn an average-risk screening population, this cfDNA blood-based test had 83% sensitivity for colorectal cancer, 90% specificity for advanced neoplasia, and 13% sensitivity for advanced precancerous lesions. (Funded by Guardant Health; ECLIPSE ClinicalTrials.gov number, NCT04136002.)

Colorectal Neoplasia in Asian Americans Undergoing First Time Asymptomatic Average-risk Screening Colonoscopies.

We identified the prevalence and subtype of colorectal neoplasia removed during index screening colonoscopies in a large Asian American population. Asian Americans are the fastest growing demographic group in the United States yet there is a paucity of data on the characteristics of colorectal neoplasia found in this cohort. Cross-sectional study of 2208 index colonoscopies performed on average-risk Asian and White patients at a large, tertiary academic center. Patients were identified via diagnostic or procedure codes between 2015 and 2020, with retrospective classification of polyp histopathology. Univariate and multivariate analysis were performed to identify risk factors associated with colorectal neoplasia. A total of 2208 patients were identified, of which 1085 were Asian. When adjusted for age and sex, Asians were as likely as Whites to have any type of colorectal neoplasia [44.2% vs. 43.5%, odds ratio (OR)=0.93, (CI: 0.78-1.11)]. On multivariate analysis, Asians were less likely to have sessile serrated polyps (5.5% vs. 9.9%, OR=0.53, 95% CI: 0.38-0.73) and more likely to have tubular adenomas in the left colon (22.6% vs. 18.0%, OR=1.33, 95% CI: 1.08-1.64) compared with Whites. Quality measures, such as sessile serrated polyp detection rates, may need to take into account demographic factors such as race. The prevalence of colorectal neoplasia among Asian Americans is substantial and warrants efforts to promote optimal uptake of colorectal cancer screening tests.

Multisite external validation of blood test for colorectal neoplasia screening in a majority average-risk screening cohort of 449 subjects.

66 Background: The FirstSight CRC screening blood test was previously shown to have sensitivities of 92.1% and 54.5% for CRC and AA at a specificity of 90.6% for 1,038 subjects from 18 clinical sites. In this report, we describe the independent external validation of the predefined FirstSight CRC screening blood test with new subjects from 16 sites dispersed across the US, 4 of which are new and did not participate in the previous study. Methods: The validation study included subjects from two sources: Average-risk, asymptomatic screening subjects from screening clinics supplemented with diseased-only subjects from surgical oncology centers. Blood was drawn before bowel prep for colonoscopy or treatment. External validation as well as Monte Carlo cross-validation (MCCV) methods were used to evaluate the performance of the pre-defined FirstSight assay, algorithm, and clinical thresholds in this independent external validation set. Results include sensitivity and specificity to detect CRC and AA and 95% confidence intervals. Results: The study cohort (55.2% female; mean age 56.9 yrs.) consisted of 449 subjects (White 61.7%; Black 14.5%; Hispanic 18%; AAPI and Middle Easterners 5.8%). The majority of them, 376 (84%), were asymptomatic, average-risk screening subjects (including 1 CRC, 53 AA, and all 322 negative subjects). An additional 73 (16%) diseased subjects (39 CRC and 34 AA) were enriched due to low disease prevalence. The FirstSight algorithm derives a test score from 0 to 100 as a quantitative measure of AA and CRC risk with a cutpoint to assign a binary low- or high-risk designation. The previously described cutpoint of 47.2 yielded a test specificity of 90.0%, and 90.0% and 52.9% sensitivity for the detection of CRC and AA, respectively. Here we report a higher cutpoint 50 with identical sensitivities but improved specificity to 90.7%. Point estimates of sensitivity and specificity, including CRC staging, and Clopper-Pearson exact 95% confidence intervals based on the external validation results are presented below. Conclusions: An external validation included 449 subjects from a multi-site, majority average-risk CRC screening study successfully validated the FirstSight Blood Test’s high performance as previously established with 1,038 subjects. The results bring forth confidence in the Test’s reproducibility in a large-scale clinical trial. Clinical trial information: NCT05127096 . [Table: see text]

Prospective study of a multi-modal blood-based test for colorectal cancer screening.

70 Background: Colorectal cancer (CRC) screening has proven to be a useful tool for the detection and prevention of CRC. However, adherence is low despite the multiple screening options available. A blood-based CRC screening test with optimized sensitivity and specificity may improve screening adherence. We aimed to prospectively evaluate the performance of a multimodal blood-based colorectal neoplasia screening test in individuals presenting for colonoscopy. Methods: This prospective, observational study was developed in four hospitals in Spain and enrolled individuals (45 – 84 years of age) undergoing colonoscopy, including diagnostic and screening colonoscopies, between March 2020 and September 2021. Eligible individuals consented to use of medical records for research and to provide a blood sample prior to colonoscopy procedure. Individuals were followed for one year. Whole blood was collected and shipped ambient to a central laboratory for analysis (Shield, Guardant Health, Redwood City, CA, USA). The blood-based colorectal neoplasia test is a 500kb next-generation sequencing based panel and bioinformatic platform that incorporates cell-free DNA (cfDNA) methylation-based partitioning to identify cancer related genomic alterations and epigenomic modifications (methylation and modifications in chromatin state). Results are integrated to yield a binary “positive” or “negative” result. Here we present findings correlating the blood-based test results with colonoscopy findings and findings from available 1-year follow-up data. Results: 556 out of 598 eligible individuals had an evaluable colonoscopy and a blood-based test result that passed quality control standards. Of the 556 individuals, 52% were female; median age was 55 years (21% age 45 – 49, 74% age 50 – 74, 4% age 75+). Reasons for colonoscopy were symptoms (49%), average risk screening (33%), positive stool-based test (6%), positive family history (11%) or other reasons (1%). Colorectal adenocarcinoma prevalence rate was 1.4%. Sensitivity for CRC detection was 100% (8/8; Stage I, 1; Stage II, 3; Stage III, 2; Stage IV, 2). Sensitivity for advanced adenoma (AA) detection was 22%. Specificity for advanced neoplasia (CRC + AA) was 91%. Negative predictive value (NPV) for CRC detection was 100% and positive predictive value (PPV) was 13%. 1-year follow-up data was available for 504 individuals, of whom 9 patients developed cancer (none CRC), of whom 1 had an initial positive Shield result. Conclusions: In this prospective study of individuals eligible for colonoscopy, sensitivity and specificity of the blood-based test showed a performance consistent with the available stool-based non-invasive screening options. This, combined with a more acceptable mode of testing suggests that this blood-based test may be a viable CRC screening option.

Adenoma-Based Colonoscopy Quality Metrics for the 45–49 Years Old Military Screening Population

BACKGROUND AND AIMSWith the rising incidence of colorectal cancer in younger individuals, guidelines now recommend initiating average-risk screening at age 45 years. We sought to assess the impact of this younger screening population on established and emerging colonoscopy quality metrics. METHODSWe compared all well-described lesion detection rates by colonic segment removed during initial, average-risk screening colonoscopies in the San Antonio Market military healthcare network from July 2019 to September 2022. RESULTSA total of 2165 colonoscopies met the inclusion criteria, with 755 (34.9%) colonoscopies performed on patients aged 45-49 years old. The detection rates for adenomas, proximal adenomas, advanced adenomas, and adenomas per colonoscopy were lower in the 45-49 years old group (33.4%, 18.7%, 3.8%, and 0.58, respectively) compared with the 50-75 years old group (42.7%, 24.2%, 7.7%, and 1.11, respectively; all P < 0.05). There was no difference in serrated polyp detection in the 45-49 years old group (11.5%) compared with the 50-75 years old group (12.5%; P = 0.287). There were no differences in withdrawal times, cecal intubation rates, or bowel preparation adequacy across age groups. CONCLUSIONIn our screening population, we found that adenoma-based colonoscopy quality metrics were significantly lower in the 45-49 years old population compared to the traditional screening age cohort, while there was no difference in serrated polyp detection. Endoscopists should anticipate a small decline in colonoscopy quality benchmarks as the screening population becomes younger, although these results require validation through multicenter, prospective monitoring.

Estimate of Increase in Colorectal Cancer Diagnoses with Expansion of Fecal Immunochemical Testing in an Urban Safety-Net Population.

Fecal immunochemical test (FIT) is less effective in detecting advanced adenomas (AA) than colonoscopy. Increase in FIT for colorectal cancer (CRC) screening may lead to an increased number of undetected AAs which may develop into future CRCs. We determined the potential impact of FIT expansion on missed AAs and future CRC diagnoses in an urban, tertiary-care, safety-net hospital. CRC and AA diagnoses were identified in patients undergoing colonoscopy for average-risk CRC screening or positive FIT between 2017 and 2019 at Boston Medical Center. Poisson regression modeling was used to estimate the frequency of AAs per year by age group using data from 2017 to 2019, assuming average outpatient volume and proportion of screening colonoscopies. Total number of patients who received FIT was extrapolated from those who underwent colonoscopy for positive FIT. We estimated AAs per year if 'one-time' FIT was used for screening in 75% and 100% of the population and subtracted this from the estimated AAs per year under the Poisson model to determine missed AAs. We used previously described, age and gender specific estimates of the annual progression of AA to CRC. The estimated number of CRCs detected per year is 4.6/1785 males and 4.6/2086 females screened. With 75% FIT expansion, we estimate an additional 3.5 (95% CI 1.3, 9.5) and 2.2 (95% CI 0.64, 7.6) CRCs; with 100% FIT expansion, we estimate an additional 7.4 (95% CI 3.7, 14.9) and 4.2 (95% CI 1.7, 10.5) CRCs, in 5years, in males and females, respectively. Expansion of FIT may substantially increase CRC incidence.

Personalized Multilevel Intervention for Improving Appropriate Use of Colorectal Cancer Screening in Older Adults

Despite guideline recommendations, clinicians do not systematically use prior screening or health history to guide colorectal cancer (CRC) screening decisions in older adults. To evaluate the effect of a personalized multilevel intervention on screening orders in older adults due for average-risk CRC screening. Interventional 2-group parallel unmasked cluster randomized clinical trial conducted from November 2015 to February 2019 at 2 US Department of Veterans Affairs (VA) facilities: 1 academic VA medical center and 1 of its connected outpatient clinics. Randomization at the primary care physician/clinician (PCP) level, stratified by study site and clinical full-time equivalency. Participants were 431 average-risk, screen-due US veterans aged 70 to 75 years attending a primary care visit. Data analysis was performed from August 2018 to August 2023. The intervention group received a multilevel intervention including a decision-aid booklet with detailed information on screening benefits and harms, personalized for each participant based on age, sex, prior screening, and comorbidity. The control group received a multilevel intervention including a screening informational booklet. All participants received PCP education and system-level modifications to support personalized screening. The primary outcome was whether screening was ordered within 2 weeks of clinic visit. Secondary outcomes were concordance between screening orders and screening benefit and screening utilization within 6 months. A total of 436 patients were consented, and 431 were analyzed across 67 PCPs. Patients had a mean (SD) age of 71.5 (1.7) years; 424 were male (98.4%); 374 were White (86.8%); 89 were college graduates (21.5%); and 351 (81.4%) had undergone prior screening. A total of 258 (59.9%) were randomized to intervention, and 173 (40.1%) to control. Screening orders were placed for 162 of 258 intervention patients (62.8%) vs 114 of 173 control patients (65.9%) (adjusted difference, -4.0 percentage points [pp]; 95% CI, -15.4 to 7.4 pp). In a prespecified interaction analysis, the proportion receiving orders was lower in the intervention group than in the control group for those in the lowest benefit quartile (59.4% vs 71.1%). In contrast, the proportion receiving orders was higher in the intervention group than in the control group for those in the highest benefit quartile (67.6% vs 52.2%) (interaction P = .049). Fewer intervention patients (106 of 256 [41.4%]) utilized screening overall at 6 months than controls (96 of 173 [55.9%]) (adjusted difference, -13.4 pp; 95% CI, -25.3 to -1.6 pp). In this cluster randomized clinical trial, patients who were presented with personalized information about screening benefits and harms in the context of a multilevel intervention were more likely to receive screening orders concordant with benefit and were less likely to utilize screening. ClinicalTrials.gov Identifier: NCT02027545.

Effect of aspirin, warfarin, and proton-pump inhibitors on performance of fecal immunochemical test in colorectal cancer screening: a systematic review and meta-analysis.

This study aims to investigate the impact of antithrombotic agents and proton-pump inhibitors (PPIs) on fecal immunochemical test (FIT). PubMed, EMBASE, Web of Science, Cochrane Central, and Google Scholar were searched from inception until September 3, 2023. Studies comparing the diagnostic performance of FIT between medicine users and non-users in average-risk colorectal cancer screening populations were included. Pooled sensitivity, specificity, and positive predictive values (PPVs) for advanced neoplasia (AN) of FIT were compared by reporting pooled odds ratios (ORs) with 95% confidence intervals (CIs) using a random-effects model. Twenty-two studies enrolling 5,572,367 individuals were included. For aspirin, pooled sensitivity and specificity for AN were 57.2% and 88.4% in users versus 60.2% and 93.2% in non-users; while pooled ORs were 1.49 (95% CI 0.89-2.48, P = 0.13) and 0.72 (95% CI 0.62-0.83, P < 0.001), respectively. In subgroup analysis, there was no difference in sensitivity and specificity between the two groups at the cutoff of 20μg Hb/g (P = 0.57 and 0.29, respectively) but a significantly lower specificity in users compared with non-users at lower cutoffs (P < 0.001). Moreover, a significantly lower PPVAN in users compared with non-users was observed after matching age and sex confounders (P = 0.001). Warfarin had no significant influence on PPVAN of FIT (P = 0.43). PPIs were associated with a significantly lower PPVAN in users (P < 0.001). Aspirin use was associated with lower specificity and PPV of FIT. Aspirin discontinuation before FIT to reduce false-positive results should be interpreted with caution given concerns about cardiovascular events. Increasing cutoff values of FIT in aspirin users may be another possible approach. Additionally, warfarin withdrawal before FIT is unnecessary but PPIs withdrawal before FIT is recommended to reduce false-positive results.

S730 Higher Rates of Endoscopic Mucosal Resection (EMR) in Colonoscopy Following Positive Stool Test vs Average Risk Screening

S730 Higher Rates of Endoscopic Mucosal Resection (EMR) in Colonoscopy Following Positive Stool Test vs Average Risk Screening

S3056 Average Risk Screening Colonoscopy Complicated by Intramural Hematoma and Hemoperitoneum in a Patient Without Any Risk Factor

S3056 Average Risk Screening Colonoscopy Complicated by Intramural Hematoma and Hemoperitoneum in a Patient Without Any Risk Factor

S386 Assessing for Racial and Ethnic Disparities in Initial Average Risk Screening Colonoscopy Quality Metrics in a Large Military Gastroenterology Fellowship Program

S386 Assessing for Racial and Ethnic Disparities in Initial Average Risk Screening Colonoscopy Quality Metrics in a Large Military Gastroenterology Fellowship Program