Stool-based Colorectal Cancer Screening Research Articles

Evaluating Colonoscopy Quality by Performing Provider Type.

Colorectal Cancer (CRC) is the third most diagnosed cancer and the second leading cause of cancer death in the United States. Colonoscopy is an essential tool for screening, used both as a primary approach and follow-up to an abnormal stool-based CRC screening result. Colonoscopy quality is often measured with four key indicators: bowel preparation, cecal intubation, mean withdrawal time, and adenoma detection. Colonoscopies are most often performed by gastroenterologists (GI), however, in rural and medically underserved areas non-GI providers often perform colonoscopies. This study aims to evaluate the quality and safety of screening colonoscopies performed by non-GI providers, comparing their outcomes to those of GI providers. Descriptive statistics were used to characterize the study population. Results for quality indicators were stratified by provider type and compared. Statistical significance was determined using p < 0.05 as the threshold for all comparisons; all p-values were two-sided. No statistical difference was found when comparing performance by provider type. Median performance for gastroenterologists, general surgeons, and family medicine providers ranged form 98-100% for cecal intubation; 97.4-100% for bowel preparation; 57.4-88.9% for male adenoma detection rate; 47.7-62.13% for female adenoma detection rate; and 0:12:10-0:20:16 for mean withdrawal time. All provider types met and exceeded the goal metric for each of the quality indicators (p < 0.001). In this analysis, non-GI providers can be expected to perform colonoscopies with similar quality to GI providers based on performance outcomes for the key quality metrics.

The multitarget faecal immunochemical test for improving stool-based colorectal cancer screening programmes: a Dutch population-based, paired-design, intervention study

The faecal immunochemical test (FIT) is widely employed for colorectal cancer screening. However, its sensitivity for advanced precursor lesions remains suboptimal. The multitarget FIT (mtFIT), measuring haemoglobin, calprotectin, and serpin family F member 2, has demonstrated enhanced sensitivity for advanced neoplasia, especially advanced adenomas, at equal specificity to FIT. This study aimed to prospectively validate and investigate the clinical utlitity of mtFIT versus FIT in a setting of population-based colorectal cancer screening. Individuals aged 55-75 years and who were eligible for the Dutch national FIT-based colorectal cancer screening programme were invited to submit both a FIT and mtFIT sample collected from the same bowel movement. Positive FIT (47 μg/g haemoglobin cutoff) or mtFIT (based on decision-tree algorithm) led to a colonoscopy referral. The primary outcome was the relative detection rate of mtFIT versus FIT for all advanced neoplasia. Secondary outcomes were the relative detection rates of colorectal cancer, advanced adenoma, and advanced serrated polyps individually and the long-term effect of mtFIT-based versus FIT-based programmatic screening on colorectal cancer incidence, mortality, and cost, determined with microsimulation modelling. The study has been registered in ClinicalTrials.gov, NCT05314309, and is complete. Between March 25 and Dec 7, 2022, 35 786 individuals were invited to participate in the study, of whom 15 283 (42·7%) consented, and 13 187 (86·3%) of 15 283 provided both mtFIT and FIT samples with valid results. Of the 13 187 participants, 6637 (50·3%) were male and 6550 (49·7%) were female. mtFIT showed a 9·11% (95% CI 8·62-9·61) positivity rate and 2·27% (95% CI 2·02-2·54) detection rate for advanced neoplasia, compared with a positivity rate of 4·08% (3·75-4·43) and a detection rate of 1·21% (1·03-1·41) for FIT. Detection rates of mtFIT versus FIT were 0·20% (95% CI 0·13-0·29) versus 0·17% (0·11-0·27) for colorectal cancer; 1·64% (1·43-1·87) versus 0·86% (0·72-1·04) for advanced adenoma, and 0·43% (0·33-0·56) versus 0·17% (0·11-0·26) for advanced serrated polyps. Modelling demonstrated that mtFIT-based screening could reduce colorectal cancer incidence by 21% and associated mortality by 18% compared with the current Dutch colorectal cancer screening programme, at feasible costs. Furthermore, at equal positivity rates, mtFIT outperformed FIT in terms of diagnostic yield. At an equally low positivity rate, mtFIT-based screening was predicted to further decrease colorectal cancer incidence by 5% and associated mortality by 4% compared with FIT-based screening. The higher detection rate of mtFIT for advanced adenoma compared with FIT holds the potential to translate into additional and clinically meaningful long-term colorectal cancer incidence and associated mortality reductions in programmatic colorectal cancer screening. Stand Up to Cancer, Dutch Cancer Society, Dutch Digestive Foundation, and Health~Holland.

Abstract A138: Impact of racial disparities in follow-up colonoscopy for abnormal stool-screening test results on colorectal cancer incidence and mortality: A simulation modeling analysis

Abstract Introduction: The benefits of colorectal cancer (CRC) screening programs for average-risk adults rely on completion of follow-up colonoscopy (FU-Col) after a positive result from either the stool-based fecal immunochemical test (FIT) or multi-target stool DNA (mt-sDNA) test. Existing data demonstrate significantly lower rates of FU-Col for Black Americans than White Americans. However, the contribution of differential FU-Col rates on disparate CRC outcomes among Black and White Americans has not been rigorously evaluated. Methods: We used the CRC-Adenoma Incidence and Mortality (CRC-AIM) model as our analysis platform, with inputs from published literature that report Black adults are approximately 15% less likely to complete FU-Col compared to White adults. CRC-AIM was validated against United Kingdom Flexible Sigmoidoscopy Screening Trial and three National Cancer Institute’s Cancer Intervention and Surveillance Modeling Network (CISNET) CRC models. We simulated screening with annual FIT and triennial mt-sDNA between ages 45 and 75 versus no screening. We considered two scenarios that assumed perfect adherence to FIT/mt-sDNA screening: 1) FU-Col rates for Black adults are 15% lower than those for White adults; 2) Black adults have the same FU-Col rates as White adults. In a secondary analysis, we considered real-world adherence to FIT (43%) and mt-sDNA (66%) and reran these two scenarios. Lifetime outcomes per 1,000 individuals were reported. Results: Assuming perfect adherence to FIT/mt-sDNA screening and 15% lower FU-Col rates, estimated life-year gains (LYG) from annual FIT and triennial mt-sDNA screening strategies compared to no screening was 227 and 239 per 1,000 individuals, respectively. If Black adults had the same FU-Col rates as White adults, the LYG would increase to 243 and 256 for FIT and mt-sDNA screening, respectively, which corresponds to a 7% improvement in LYG. Furthermore, elimination of racial disparities in FU-Col rates would reduce CRC incidence by 8% and 9% for FIT and mt-sDNA screening, respectively and reduce CRC mortality by 10% for both FIT and mt-sDNA screening. Secondary analysis shows that eliminating disparities in FU-Col would lead to 9-11% improvement in LYGs, 5-9% improvement in CRC incidence, and 7-11% improvement in CRC mortality for Black adults considering the real-world adherence to FIT/mt-sDNA screening. Conclusions: Data from this novel simulation modeling study that accounts for differences in FU-Col rates between Black and White Americans suggest that focused efforts to eliminate this gap would improve the anticipated LYG, CRC incidence, and CRC mortality benefits associated with stool-based CRC screening by over 7%, 8%, and 10%, respectively. Further investigation of this under-appreciated contributor to established racial disparities in CRC control may lead to innovative solutions for improving health equity. Citation Format: Oguz Alagoz, A. Mark Fendrick, Vahab Vahdat, Chris Estes, A. Burak Ozbay, Travelle Ellis, Paul J. Limburg, Durado Brooks. Impact of racial disparities in follow-up colonoscopy for abnormal stool-screening test results on colorectal cancer incidence and mortality: A simulation modeling analysis [abstract]. In: Proceedings of the 16th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2023 Sep 29-Oct 2;Orlando, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2023;32(12 Suppl):Abstract nr A138.

A Call to Action to Increase Uptake of Follow-Up Colonoscopy After Initial Positive Stool-Based Colorectal Cancer Screening.

A Call to Action to Increase Uptake of Follow-Up Colonoscopy After Initial Positive Stool-Based Colorectal Cancer Screening.

Effects of Academic Detailing, Panel Management and Mailed Multi-Target Stool-DNA Testing on Colorectal Cancer Screening.

Academic detailing, patient-panel management, and mailed, stool-based testing have each been utilized to increase colorectal cancer (CRC) screening in rural clinics. The effectiveness of combining these interventions to increase CRC screening during COVID-19 restrictions was unclear. We explored the effects of a multi-component intervention including academic detailing, active patient panel management, and mailed MT-sDNA testing on colorectal cancer screening in our rural family medicine clinic. Baseline interventions included EMR-based provider alerts and mailed patient reminders. Our intervention (March-May 2020) and follow-up periods (June-August 2020) coincided with the initial COVID-19 surge, giving us the opportunity to observe the effects of our intervention during COVID-19 restrictions. A total of 407 patients were eligible and overdue for colorectal cancer screening. Our clinic's CRC screening rate increased significantly after intervention (69.7%) as compared with before (64.3%) (P = <0.01; 95%CI = 5.39-5.4). Our clinic's CRC screening rates increased significantly during the initial 3 months of the COVID-19 surge (67.8%) compared with the same period the prior year. (62.3%) (P = .003; 95%CI = 3.4-7.6). Our CRC screening rates increased after intervention (69.7%) compared with our regional health system (67%) (P = <0.01; 95%CI = 2.6-2.77). Our weekly stool-based CRC screening increased (94% increase) compared with other health systems nationally (61 to 83% decrease). A multi-component intervention, including academic detailing, panel management, and mailed MT-sDNA testing, can lead to significant increases in CRC screening in a rural family medicine clinic, empowering providers to maintain an effective CRC screening outreach during COVID-19 related restrictions.

Impact of Eliminating Cost-Sharing by Medicare Beneficiaries for Follow-Up Colonoscopy After a Positive Stool-based Colorectal Cancer Screening Test.

A follow-up colonoscopy after a positive stool-based colorectal cancer screening test is necessary to complete the full screening process. Policies that remove cost barriers to completing colorectal cancer screening may lead to increases in overall participation rates and use of follow-up colonoscopy, improving clinical and economic outcomes.

Patient perspectives on a proposed pharmacy-based colorectal cancer screening program.

Colorectal cancer (CRC) is a common and preventable cancer. CRC screening is underutilized, particularly within medically underserved communities. Most interventions aimed at increasing CRC screening are delivered through primary care clinics. Pharmacies are more accessible than traditional primary care settings and may be ideally suited for delivering CRC screening and increasing access. Fecal immunochemical test is an at-home, stool-based CRC screening test that could be distributed through pharmacies. The purpose of our study was to assess patient perspectives on receiving fecal immunochemical test-based CRC screening through pharmacies. We conducted semi-structured interviews with participants residing in North Carolina and Washington. Interviews explored acceptability and intervention design preferences for a pharmacy-based CRC screening program. The interview guide was informed by Andersen's Healthcare Utilization Model and the Theoretical Domains Framework. Interviews were conducted at the University of North Carolina at Chapel Hill and Fred Hutchinson Cancer Research Center, audio-recorded, and transcribed. Patients perceived a pharmacy-based CRC screening program to be highly acceptable, citing factors such as ease of pharmacy access and avoiding co-pays for an office visit. Some concerns about privacy and coordination with patients' primary care provider tempered acceptability. Trust and positive relationships with providers and pharmacists as well as seamless care across the CRC screening continuum also were viewed as important. Patients viewed pharmacy-based CRC screening as an acceptable option for CRC screening. To improve programmatic success, it will be important to ensure privacy, determine how communication between the pharmacy and the patient's provider will take place, and establish closed-loop care, particularly for patients with abnormal results.

The cost-effectiveness of non-invasive stool-based colorectal cancer screening offerings from age 45 for a commercial and medicare population

AimThe United States Preventive Services Taskforce (USPSTF) recently recommended lowering the age for average-risk colorectal cancer (CRC) screening from 50 to 45 years. While initiating screening at age 45 versus 50 provides a greater opportunity for CRC early detection and prevention, the full profile of benefits, risks, and cost-effectiveness of expanding the screen-eligible population requires further evaluation.Materials and methodsThe costs and clinical outcomes for screening at age 45 for triennial multi-target stool DNA [mt-sDNA], and other non-invasive stool-based modalities (annual fecal immunochemical test [FIT] and annual fecal-occult blood test [FOBT]), were estimated using the validated CRC-AIM microsimulation model over a lifetime horizon. Test sensitivity and specificity inputs were based on 2021 USPSTF modeling analyses; adherence rates were based on published real-world data and the costs of the screening test, follow-up colonoscopies, complications, and CRC care were included. Outcomes are reported from the perspective of a United States payer as clinical, life-years gained (LYG), and incremental cost-effectiveness ratio (ICER); stool-based and follow-up colonoscopy adherence ranges were explored in one-way, probabilistic and threshold analyses.ResultsWhen compared to initiation of CRC screening at age 45 versus 50, all modalities reduced both the incidence of and mortality from CRC and increased LYG. Initiating CRC screening at age 45 was cost-effective with an ICER of $59,816 and $35,857 per quality-adjusted life year (QALY) for mt-sDNA versus FIT and FOBT, respectively. In the threshold analyses, at equivalent rates to stool-based screening, mt-sDNA was always cost-effective at a willingness-to-pay threshold of $100,000 per QALY versus FIT and FOBT.ConclusionsInitiating average-risk CRC screening at age 45 instead of age 50 increases the estimated clinical benefit by reducing disease burden while remaining cost-effective. Among stool-based screening modalities, mt-sDNA provides the most clinical benefit in a Commercial and Medicare population.

Using the Multi-Theory Model (MTM) of Health Behavior Change to Explain the Seeking of Stool-Based Tests for Colorectal Cancer Screening.

Colorectal cancer is the third most common cancer worldwide and is the second leading cause of cancer-associated deaths. While colorectal cancer is on the decline in the United States (US), disparities still exist, despite the non-invasive screening modalities, such as stool-based tests have shown themselves to be effective in the detection of colorectal cancer. Many of the existing stool-based test interventions lack the use of a contemporary theory-based approach. Given the paucity of theory-based interventions intended to promote stool-based tests, this cross-sectional study utilizes the multi-theory model (MTM) of health behavior change to explain the seeking of stool-based tests for colorectal cancer (CRC) screening. An online 57-item questionnaire with an established psychometric validity was used to collect responses from the US-based sample (n = 640) of adults aged 45-75 years old. The data were analyzed using bivariate and multivariate statistical methods. Structural equation modeling (SEM) was conducted to test the construct validity of the survey instrument. In this nationwide sample, 39.2% (n = 251) of participants reported having received some form of a stool-based test. Among the participants who did not undergo stool-based CRC screening, the MTM subscales, including "participatory dialogue", "behavioral confidence", and "changes in the social environment", were significant predictors of initiating screening behavior and explained 48% of the variance in the initiation among this group (R2 = 0.579, F = 5.916, p < 0.001; adjusted R2 = 0.481). The MTM may be a useful framework with which to design educational, mass media, social media, and clinical interventions for the promotion of stool-based CRC screening among adults aged 45-75 years old.

Stool-Based Colorectal Cancer Screening Test Performance Characteristics in Those With and Without Hemorrhoids.

To evaluate the effect of hemorrhoids on noninvasive stool test performance for colorectal cancer (CRC) screening. We conducted a retrospective cohort study of test characteristics for the fecal immunochemical test (FIT) and the multitarget stool DNA (mt-sDNA) test, on the basis of hemorrhoid status, recorded at the time of colonoscopy, among patients enrolled in the pivotal prospective study for mt-sDNA that was conducted from June 2011, to May 2013. Test characteristics (sensitivity, specificity, positive, and negative predictive values) for FIT and mt-sDNA (performed < 90 days before colonoscopy) were stratified by the presence of hemorrhoids and compared. Hemorrhoids were found in 51.7% (5163 of 9989) of the study cohort. Across all test characteristics, there were no statistically significant differences for FIT or mt-sDNA when stratified by hemorrhoid status. Analysis revealed mt-sDNA sensitivity of 44% and 41% for advanced precancerous lesions in nonhemorrhoidal and hemorrhoid patients, respectively (P=.41). The FIT sensitivity among the same lesion category was 24.9% in patients without hemorrhoids and 22.8% in those with hemorrhoids (P=.48). The mt-sDNA specificity was 86.4% in patients without hemorrhoids vs 87.7% in those with hemorrhoids (P=.67), although FIT specificity was 95.0% among patients without hemorrhoids vs 94.7% in those with hemorrhoids (P=.44). The presence of asymptomatic hemorrhoids did not adversely affect test performance in this large clinical study. These findings suggest that in the absence of overt gastrointestinal bleeding, FIT and mt-sDNA are options for CRC screening, irrespective of hemorrhoid status. clinicaltrials.gov Identifier: NCT01397747.

Changes in uptake of stool-based colorectal cancer screening during the Covid-19 pandemic.

Colorectal cancer (CRC) screening is underutilized and endoscopic colon screening includes a number of barriers that were exacerbated by the Covid-19 pandemic. At-home stool-based screening (SBS) increased during the pandemic and potentially reached eligible adults hesitant to be screened by endoscopy. The purpose of this analysis was to examine the change in uptake of SBS during the pandemic among adults not screened within guidelines by endoscopy. We used data from the 2019 and 2021 National Health Interview Surveys to estimate uptake of SBS among adults aged 50-75years, without a previous diagnosis of CRC and without guideline-concordant endoscopic screening. We also examined provider recommendations for screening tests. To examine if changes in uptake differed during the pandemic by demographic and health characteristics, we combined survey years and ran logistic regression models with an interaction term for each factor and survey year. In our study population, SBS increased 74% overall from 2019 to 2021 (8.7% to 15.1%; p < 0.001), with the largest percent increase among those aged 50-52years (3.5% to 9.9%; p < 0.001). Among those aged 50-52years, the ratio of endoscopy to SBS changed from 83%/17% in 2019 to 55%/45% in 2021. Cologuard was the only screening test where recommendations by healthcare providers significantly increased from 2019 (10.6% to 16.1%; p = 0.002). Use and recommendations for SBS increased substantially during the pandemic. Increased awareness among patients could potentially improve future CRC screening rates if uptake of SBS occurs among those unable or unwilling to be screened by endoscopy.

Colorectal cancer screening with blood-based tests: Estimated impact of a 1-, 2-, or 3-year screening interval compared with annual FIT and triennial mt-sDNA strategies.

10580 Background: Blood-based tests are an emerging option for non-invasive colorectal cancer (CRC) screening for which the Centers for Medicare &amp; Medicaid Services (CMS) has proposed coverage every 3 years for average-risk individuals. Analyses with the CRC-AIM microsimulation model demonstrated that triennial screening with blood-based tests with CMS minimum performance often yields inferior outcomes to stool-based CRC screening (fecal immunochemical test [FIT] and multi-target stool DNA [mt-sDNA]). CRC-AIM was used to explore the impact of blood-based screening intervals, using reported performance characteristics from the ECLIPSE study (Guardant Health, Inc.)1, on estimated clinical outcomes vs FIT and mt-sDNA screening. Methods: Outcomes were simulated for average-risk individuals screened between ages 45-75 years. Intervals were set at 1, 2, or 3 years for blood-based, 3 years for mt-sDNA and annually for FIT screening. The blood-based test was modeled at 83% CRC sensitivity, 13% advanced adenoma sensitivity, and 90% specificity. Perfect adherence (100%) was modeled for blood-based tests and real-world adherence rates used for CRC initial screening tests (mt-sDNA=65.6%; FIT=42.6%) and follow-up colonoscopy (mt-sDNA=72.1%; FIT=46.0%). Primary outcomes were life-years gained (LYG) and colonoscopies (COL) per 1000 individuals for blood-based screening compared to mt-sDNA and FIT. As a secondary analysis, estimates were generated with perfect (100%) adherence assumed for initial screening and follow-up colonoscopy for mt-sDNA and FIT as well. Results: Blood-based testing at a 3-year interval with 100% adherence led to 11% fewer LYG than mt-sDNA at RWE adherence (240 vs 270, respectively), and 9% more COL (1402/1000 vs 1288/1000). Meanwhile, blood-based testing at a 1-year interval and perfect adherence (best case scenario) resulted in the lowest LYG per COL ratio across all scenarios (16% more LYG and 87% more COL compared to mt-sDNA at RWE adherence). Blood-based test results showed similar trends when compared to FIT. Conclusions: Outcomes for blood-based screening every 3 years based on reported test performance characteristics and unrealistic perfect adherence demonstrate fewer LYG as compared to either mt-sDNA or FIT. When compared to real-world adherence for mt-sDNA and FIT, blood-based tests with 1- and 2-year intervals and perfect adherence had higher LYG with the tradeoff of a greater number of diagnostic colonoscopies. [Table: see text]

Psychosocial, behavioral, and communication factors associated with completion of the mt-sDNA test for colorectal cancer screening.

60 Background: Colorectal cancer (CRC) screening has been shown to reduce CRC incidence and mortality. Several CRC screening modalities are guideline recommended for average-risk adults aged 45-75 years. CRC screening is underutilized in the US and access to facility-based options, such as colonoscopy, represents a potential barrier. Home-based stool tests are guideline-endorsed and offer a convenient, accessible, scalable option for CRC screening. Thus, understanding the factors that influence completion of stool-based CRC screening is important to guide interventions to improve adherence. We developed a survey, informed by behavioral theory, to identify psychosocial, behavioral and communication factors associated with completion of mt-sDNA screening. Methods: The survey instrument was finalized through expert review, quality testing, and cognitive testing. Adults aged 45-75 years, with a US postal address, who received a valid order for mt-sDNA and whose kit was shipped between 5/21-9/21 were eligible for sampling. RTI administered the survey between 3/22-6/22. Participants had the option to complete electronic or paper surveys. We fit a multivariable logistic regression to identify factors significantly associated with mt-sDNA test completion. Results: Of 17,370 individuals invited to participate, 2,973 completed the survey (AAPOR RR3 = 21.7%); 77.3% of the sample completed the mt-sDNA test. Responders and non-responders did not differ significantly by sex or age. Controlling for demographic characteristics and insurance status, the odds of mt-sDNA test completion were significantly higher among participants who reported greater perceived test effectiveness (OR = 1.20), greater ease (OR = 4.06), and greater comfort in test use (OR = 1.18). Odds of test completion were significantly higher among participants who reported their healthcare provider discussed the mt-sDNA test with them (OR = 2.01) and involved them a great deal in decision making about CRC screening (OR = 1.29). Participants who expressed greater worry about developing CRC were less likely to return their mt-sDNA kit (OR = 0.81). Conclusions: To improve population adherence to CRC screening recommendations, efforts are needed to ensure patients understand the attributes and effectiveness of available test options and feel adequately prepared to complete their preferred screening test. Additionally, healthcare providers must be appropriately prepared and resourced to educate and to engage patients in shared decision-making about CRC screening.

Acceptability of alternative technologies compared with faecal immunochemical test and/or colonoscopy in colorectal cancer screening: A systematic review.

Colorectal cancer (CRC) is the third most common cancer and the second largest cause of cancer-related death worldwide. Current CRC screening in various countries involves stool-based faecal immunochemical testing (FIT) and/or colonoscopy, yet public uptake remains sub-optimal. This review assessed the literature regarding acceptability of alternative CRC screening modalities compared to standard care in average-risk adults. Systematic searches of MEDLINE, EMBASE, CINAHL, Cochrane and Web of Science were conducted up to February 3rd, 2022. The alternative interventions examined were computed tomography colonography, flexible sigmoidoscopy, colon capsule endoscopy and blood-based biomarkers. Outcomes for acceptability were uptake, discomfort associated with bowel preparation, discomfort associated with screening procedure, screening preferences and willingness to repeat screening method. A narrative data synthesis was conducted. Twenty-one studies met the inclusion criteria. Differences between intervention and comparison modalities in uptake did not reach statistical significance in most of the included studies. The findings do suggest FIT as being more acceptable as a screening modality than flexible sigmoidoscopy. There were no consistent significant differences in bowel preparation discomfort, screening procedure discomfort, screening preference and willingness to repeat screening between the standard care and alternative modalities. Current evidence comparing standard colonoscopy and stool-based CRC screening with novel modalities does not demonstrate any clear difference in acceptability. Due to the small number of studies available and included in each screening comparison and lack of observed differences, further research is needed to explore factors influencing acceptability of alternative CRC modalities that might result in improvement in population uptake within different contexts.

Guidance for setting international standards on reporting longitudinal adherence to stool-based colorectal cancer screening

Longitudinal adherence to colorectal cancer (CRC) screening is reported using different summarizing measures, which hampers international comparison. We provide evidence to guide recommendations on which longitudinal adherence measure to report.Using adherence data over four stool-based CRC screening rounds in three countries, we calculated six summarizing adherence measures; adherence over all rounds, adherence per round, rescreening, full programme adherence (yes/no), regularity (never/inconsistent/consistent screenees) and number of times participated. For each measure, we calculated the accuracy in capturing the observed adherence patterns. Using the ASCCA model, we predicted screening effectiveness when using summarizing measures as model input versus the observed adherence patterns.Adherence over all rounds in the Italian, Spanish and Dutch cohorts was 64.9%, 42.8% and 61.5%, respectively, and the proportion of consistent screenees was 50.9%, 26.3% and 45.7%. Number of times participated and regularity were most accurate and resulted in similar model-predicted screening effectiveness as simulating the observed adherence patterns of Italy, Spain and the Netherlands (mortality reductions: 24.4%, 16.9% and 23.5%). Adherence over all rounds and adherence per round were least accurate. Screening effectiveness was overestimated when using adherence over all rounds (mortality reductions: 26.8%, 19.4% and 25.7%) and adherence per round (mortality reductions: 26.8%, 19.5% and 25.9%).To conclude, number of times participated and regularity were most accurate and resulted in similar model-predicted screening effectiveness as using the observed adherence patterns. However they require longitudinal data. To facilitate international comparison of CRC screening programme performance, consensus on an accurate adherence measure to report should be reached.

Cost-Effectiveness of Waiving Coinsurance for Follow-Up Colonoscopy after a Positive Stool-Based Colorectal Screening Test in a Medicare Population.

Follow-up colonoscopy after a positive stool-based test is necessary to complete the colorectal cancer-screening process. This analysis demonstrated that in a simulated Medicare population, waiving coinsurance for a follow-up colonoscopy improved estimated outcomes and was cost-effective when it was assumed that waiving the coinsurance modestly increased screening adherence. See related Spotlight, p. 641.

Colorectal cancer screening in sub-Saharan Africa

Colorectal cancer screening in sub-Saharan Africa

Cost-effectiveness of waiving coinsurance for follow-up colonoscopy after a positive stool-based colorectal screening test in a Medicare population.

e13624 Background: Commercial insurance plans are required to cover, with no patient cost sharing, a follow-up colonoscopy (COL) after a positive stool-based colorectal cancer (CRC) screening test. Medicare beneficiaries may still be responsible for 20% coinsurance for a follow-up COL, posing a financial barrier to screening completion. Removing the coinsurance may increase screening adherence and improve outcomes. The estimated cost-effectiveness of stool-based CRC screening was compared among adherence scenarios that assumed the status quo (20% coinsurance for follow-up COL) or waived follow-up COL coinsurance. Methods: The CRC-AIM microsimulation model simulated US Medicare beneficiaries undergoing stool-based CRC screening between ages 65-75 years. Outcomes of total costs, total quality adjusted life years (QALYs), life-years gained (LYG), CRC incidence reductions (IR), and CRC mortality reductions (MR) were calculated per 1000 individuals versus no screening using the weighted average of the outcome with multitarget stool DNA, fecal immunochemical test, and fecal occult blood test, scaled by their estimated use. Costs of follow-up COL were assumed to have 20% coinsurance in the status quo scenario. Four comparative scenarios assumed that waiving coinsurance increased published, real-world stool-based screening or follow-up COL adherence rates by 5% or 10%. Results: In scenarios where waiving coinsurance was assumed to increase screening and/or follow-up COL adherence, up to 21 more LYG and greater IR and MR were observed vs the status quo (Table). Total costs in waived coinsurance scenarios (≥$6,398) were comparable to the status quo ($6,449) as the cost savings in CRC care offset the increased COL costs. Total QALYs in waived coinsurance scenarios (≥9.3671) were greater than the status quo (9.3643) because of improved clinical outcomes. Stool-based testing in waived coinsurance scenarios was either dominant (more effective and less costly) or cost-effective at $50,000/QALY with minimal incremental costs vs the status quo. Conclusions: In a simulated Medicare population, clinical CRC outcomes improved and stool-based screening was cost-effective or cost-saving when waiving the 20% coinsurance was assumed to modestly (5%) increase adherence rates for total CRC screening and/or a COL following a positive test. [Table: see text]

An Evolutionary Algorithm to Personalize Stool-Based Colorectal Cancer Screening.

BackgroundFecal immunochemical testing (FIT) is an established method for colorectal cancer (CRC) screening. Measured FIT-concentrations are associated with both present and future risk of CRC, and may be used for personalized screening. However, evaluation of personalized screening is computationally challenging. In this study, a broadly applicable algorithm is presented to efficiently optimize personalized screening policies that prescribe screening intervals and FIT-cutoffs, based on age and FIT-history.MethodsWe present a mathematical framework for personalized screening policies and a bi-objective evolutionary algorithm that identifies policies with minimal costs and maximal health benefits. The algorithm is combined with an established microsimulation model (MISCAN-Colon), to accurately estimate the costs and benefits of generated policies, without restrictive Markov assumptions. The performance of the algorithm is demonstrated in three experiments.ResultsIn Experiment 1, a relatively small benchmark problem, the optimal policies were known. The algorithm approached the maximum feasible benefits with a relative difference of 0.007%. Experiment 2 optimized both intervals and cutoffs, Experiment 3 optimized cutoffs only. Optimal policies in both experiments are unknown. Compared to policies recently evaluated for the USPSTF, personalized screening increased health benefits up to 14 and 4.3%, for Experiments 2 and 3, respectively, without adding costs. Generated policies have several features concordant with current screening recommendations.DiscussionThe method presented in this paper is flexible and capable of optimizing personalized screening policies evaluated with computationally-intensive but established simulation models. It can be used to inform screening policies for CRC or other diseases. For CRC, more debate is needed on what features a policy needs to exhibit to make it suitable for implementation in practice.

Follow-up colonoscopy after an abnormal stool-based colorectal cancer screening result: analysis of steps in the colonoscopy completion process

BackgroundDelays in receiving follow-up colonoscopy after an abnormal fecal immunochemical test (FIT) result are associated with increased colorectal cancer incidence and mortality. Little is known about patterns of follow-up colonoscopy completion in federally qualified health centers.MethodsWe abstracted the medical records of health center patients, aged 50–75 years, who had an abnormal FIT result between August 5, 2017 and August 4, 2018 (N = 711). We assessed one-year rates of colonoscopy referral, pre-procedure visit completion, colonoscopy completion, and time to colonoscopy; associations between these outcomes and patient characteristics; and reasons for non-completion found in the medical record.ResultsOf the 711 patients with an abnormal FIT result, 90% were referred to colonoscopy, but only 52% completed a pre-procedure visit, and 43% completed a colonoscopy within 1 year. Median time to colonoscopy was 83 days (interquartile range: 52–131 days). Pre-procedure visit and colonoscopy completion rates were relatively low in patients aged 65–75 (vs. 50–64), who were uninsured (vs. insured) or had no clinic visit in the prior year (vs. ≥ 1 clinic visit). Common reasons listed for non-completion were that the patient declined, or the provider could not reach the patient.DiscussionEfforts to improve follow-up colonoscopy rates in health centers might focus on supporting the care transition from primary to specialty gastroenterology care and emphasize care for older uninsured patients and those having no recent clinic visits. Our findings can inform efforts to improve follow-up colonoscopy uptake, reduce time to colonoscopy receipt, and save lives from colorectal cancer.Trial registration: National Clinical Trial (NCT) Identifier: NCT03925883.