Stool-based Colorectal Cancer Screening Research Articles

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.

Case Study of a Comprehensive Team-Based Approach to Increase Colorectal Cancer Screening.

IntroductionColorectal cancer is the second leading cause of cancer deaths among men and women in West Virginia. In addition, 51% of all colorectal cancers diagnosed in West Virginia from 2012 to 2016 were detected at either regional (31%) or distant (20%) stages indicating a need for improved early detection.MethodsWest Virginia University Cheat Lake Physicians participated in the West Virginia Program to Increase Colorectal Cancer Screening, a program of Cancer Prevention and Control at the WVU Cancer Institute. As a result, Cheat Lake Physicians assembled a team of health care professionals to implement evidence-based interventions and system changes including provider assessment and feedback, patient reminders, accurate data capture, and tracking of CRC screening tests.ResultsThese efforts resulted in a 15.8% increase in colorectal cancer screening rates within one year of implementation. Additionally, the clinic achieved a 66% return rate for Fecal Immunochemical Test kits, an inexpensive, stool-based colorectal cancer screening test.ImplicationsThe utilization of a team-based approach to patient care yields positive results that can be carried over to other cancer and disease prevention efforts in primary care clinics.

Healthcare provider cultural competency and receptivity to colorectal cancer screening among African Americans

ABSTRACT African Americans suffer disproportionately from colorectal cancer (CRC), due in part to disparities in CRC screening. Better understanding culturally relevant psychosocial factors that impact CRC screening is therefore critical. This study examined how African Americans’ perceived cultural competency of their physician is associated with receptivity to take-home stool-based CRC screening. CRC screening deficient African Americans (N = 457) completed a patient-focused measure of perceived cultural competency and watched a brief video about CRC risks, prevention, and screening. Receptivity to stool-based CRC screening was measured using Theory of Planned Behavior (TPB) constructs . Participants were also given an opportunity to receive a no-cost at-home Fecal Immunochemical Test (FIT) kit, and we measured acceptance of this offer as a behavioral outcome (yes-no). Results showed that perceived cultural competency was associated with higher receptive attitudes, more favorable norms, greater perceived behavioral control towards stool-based screening, and also greater intentions to engage in FIT Kit screening (p < 0.001). We also found significant indirect effects of perceived cultural competency on FIT kit uptake through intention-mediated pathways. This study provides crucial evidence that participants’ perceived cultural competency may play an important role in preventive health behavior among racial minorities, including CRC screening uptake among African Americans.

Impact of Patient Adherence to Stool-Based Colorectal Cancer Screening and Colonoscopy Following a Positive Test on Clinical Outcomes.

Colorectal cancer-screening models commonly assume 100% adherence, which is inconsistent with real-world experience. The influence of adherence to initial stool-based screening [fecal immunochemical test (FIT), multitarget stool DNA (mt-sDNA)] and follow-up colonoscopy (after a positive stool test) on colorectal cancer outcomes was modeled using the Colorectal Cancer and Adenoma Incidence and Mortality Microsimulation Model. Average-risk individuals without diagnosed colorectal cancer at age 40 undergoing annual FIT or triennial mt-sDNA screening from ages 50 to 75 were simulated. Primary analyses incorporated published mt-sDNA (71%) or FIT (43%) screening adherence, with follow-up colonoscopy adherence ranging from 40% to 100%. Secondary analyses simulated 100% adherence for stool-based screening and colonoscopy follow-up (S1), published adherence for stool-based screening with 100% adherence to colonoscopy follow-up (S2), and published adherence for both stool-based screening and colonoscopy follow-up after positive mt-sDNA (73%) or FIT (47%; S3). Outcomes were life-years gained (LYG) and colorectal cancer incidence and mortality reductions (per 1,000 individuals) versus no screening. Adherence to colonoscopy follow-up after FIT had to be 4%-13% higher than mt-sDNA to reach equivalent LYG. The theoretical S1 favored FIT versus mt-sDNA (LYG 316 vs. 297; colorectal cancer incidence reduction 68% vs. 64%; colorectal cancer mortality reduction 76% vs. 72%). The more realistic S2 and S3 favored mt-sDNA versus FIT (S2: LYG 284 vs. 245, colorectal cancer incidence reduction 61% vs. 50%, colorectal cancer mortality reduction 69% vs. 59%; S3: LYG 203 vs. 113, colorectal cancer incidence reduction 43% vs. 23%, colorectal cancer mortality reduction 49% vs. 27%, respectively). Incorporating realistic adherence rates for colorectal cancer screening influences modeled outcomes and should be considered when assessing comparative effectiveness. PREVENTION RELEVANCE: Adherence rates for initial colorectal cancer screening by FIT or mt-sDNA and for colonoscopy follow-up of a positive initial test influence the comparative effectiveness of these screening strategies. Using adherence rates based on published data for stool-based testing and colonoscopy follow-up yielded superior outcomes with an mt-sDNA versus FIT-screening strategy.

Noninvasive Colorectal Cancer Screening Tests Help Close Screening Gaps During Coronavirus Disease 2019 Pandemic

The coronavirus disease 2019 (COVID-19) pandemic has upended routine preventive care across the country. Health systems worldwide have seen a drastic decrease in utilization of preventive care services, including colorectal cancer (CRC) screening.1 In response to the pandemic, the US Surgeon General advised in March 2020 that all hospitals and ambulatory surgical centers delay nonurgent surgeries and medical procedures, including screening and surveillance colonoscopies. In line with these recommendations, the University of California Los Angeles (UCLA) health system temporarily ceased elective endoscopies and purposefully encouraged the use of stool-based CRC screening modalities among patients and providers through weekly system-wide e-mails to primary care and gastroenterology providers, virtual meetings with primary care leadership, and standardized educational materials for fecal immunochemical testing (FIT).

Abstract P12: Colorectal cancer screening in Appalachian Kentucky primary care clinics during COVID-19

Abstract Background: Colorectal cancer (CRC) mortality is disproportionately higher in Appalachian counties of Kentucky than in non-Appalachian regions. Part of the mortality gap can be explained by lower screening rates in Appalachian counties. Researchers at Markey Cancer Center partnered with primary care clinics in eastern Kentucky to address this disparity by identifying strategies to implement evidence-based interventions (EBIs) to improve CRC screening and follow-up in Appalachian Kentucky. Methods: Members of the research team conducted formative research activities to identify multilevel barriers to CRC screening. A menu of EBIs was then created to address these barriers, and clinic champions selected EBIs that were feasible in their respective practices. However, because of restrictions during COVID-19, clinics experienced multiple changes to workflow and operations, necessitating modifications to program activities. Over a series of virtual meetings, clinic champions selected adaptations that could allow clinics to continue promoting CRC screening in their practices despite COVID-related limitations. Results: Changes in clinic staffing and workflow resulting from COVID-19 included provider furloughs, a state-mandated pause in elective procedures, mandatory parking lot visits for many in-person visits, and an increase in telehealth. Among our clinic partners, total in-person visits were reduced by nearly half from first to second quarter of 2020, whereas telehealth visits were 23 times higher, though telehealth visits were cut in half by third quarter. To match these changing modes of practice, clinics adapted creative strategies for communicating CRC screening recommendations to patients, including shifting from paper to digital educational tools, promoting screening via telehealth visits, and prioritizing recommendations for stool-based tests over colonoscopy for average-risk patients. As a result, orders for FIT and FIT-DNA were 2 and 3 times higher, respectively, from second to third quarter of 2020. Conclusion: Rural primary care clinics in Appalachia continue to promote CRC screening despite the multiple challenges related to COVID-19. One relevant reference for clinicians is the National Colorectal Cancer Roundtable’s playbook for reigniting CRC screening during COVID-19, a document that promotes stool-based screening for average-risk patients. While elective procedures remain backlogged in rural areas due to state regulations, research partners should emphasize the need to prioritize stool-based CRC screening for average-risk populations and reserve scheduling colonoscopies for high-risk individuals or those with abnormal stool-based test results. While our clinical partners had previously focused on a “colonoscopy first” approach to screening, our findings suggest that our clinic partners increased orders for stool-based CRC tests. Nevertheless, continued outreach is needed to ensure CRC screening rates remain optimal. Citation Format: Aaron J. Kruse-Diehr, Mark Cromo, Melinda Rogers, Angela Carman, Bin Huang, David Gross, Sue Russell, Vickie Fairchild, Mark Dignan. Colorectal cancer screening in Appalachian Kentucky primary care clinics during COVID-19 [abstract]. In: Proceedings of the AACR Virtual Meeting: COVID-19 and Cancer; 2021 Feb 3-5. Philadelphia (PA): AACR; Clin Cancer Res 2021;27(6_Suppl):Abstract nr P12.

Real-world cost-effectiveness of stool-based colorectal cancer screening in a Medicare population

Aim Multiple screening strategies are guideline-endorsed for average-risk colorectal cancer (CRC). The impact of real-world adherence rates on the cost-effectiveness of non-invasive stool-based CRC screening strategies remains undefined. Methods This cost-effectiveness analysis from the perspective of Medicare as a primary payer used the Colorectal Cancer and Adenoma Incidence and Mortality Microsimulation Model (CRC–AIM) to estimate cost and clinical outcomes for triennial multi-target stool DNA (mt-sDNA), annual fecal immunochemical test (FIT) and annual fecal occult blood test (FOBT) screening strategies in a simulated cohort of US adults aged 65 years, who were assumed to either be previously unscreened or initiating screening upon entry to Medicare. Reported real-world adherence rates for initial stool-based screening and colonoscopy follow up (after a positive stool test result) were defined as 71.1% and 73.0% for mt-sDNA, 42.6% and 47.0% for FIT, and 33.4% and 47.0% for FOBT, respectively. The incremental cost-effectiveness ratio using quality-adjusted life years (QALY) was defined as the primary outcome of interest; other cost and clinical outcomes were also reported in secondary analyses. Multiple sensitivity and scenario analyses were conducted. Results When reported real-world adherence rates were included only for initial stool-based screening, mt-sDNA was cost-effective versus FIT ($62,814/QALY) and FOBT ($39,171/QALY); mt-sDNA also yielded improved clinical outcomes. When reported real-world adherence rates were included for both initial stool-based screening and follow-up colonoscopy (when indicated), mt-sDNA was increasingly cost-effective compared to FIT and FOBT ($31,725/QALY and $28,465/QALY, respectively), with further improved clinical outcomes. Limitations Results are based on real-world cross-sectional adherence rates and may vary in the context of other types of settings. Only guideline-recommended stool-based strategies were considered in this analysis. Conclusion Comparisons of the effectiveness and benefits of specific CRC screening strategies should include both test-specific performance characteristics and real-world adherence to screening tests and, when indicated, follow-up colonoscopy.

Estimating the impact of differential adherence on the comparative effectiveness of stool-based colorectal cancer screening using the CRC-AIM microsimulation model.

BackgroundReal-world adherence to colorectal cancer (CRC) screening strategies is imperfect. The CRC-AIM microsimulation model was used to estimate the impact of imperfect adherence on the relative benefits and burdens of guideline-endorsed, stool-based screening strategies.MethodsPredicted outcomes of multi-target stool DNA (mt-sDNA), fecal immunochemical tests (FIT), and high-sensitivity guaiac-based fecal occult blood tests (HSgFOBT) were simulated for 40-year-olds free of diagnosed CRC. For robustness, imperfect adherence was incorporated in multiple ways and with extensive sensitivity analysis. Analysis 1 assumed adherence from 0%-100%, in 10% increments. Analysis 2 longitudinally applied real-world first-round differential adherence rates (base-case imperfect rates = 40% annual FIT vs 34% annual HSgFOBT vs 70% triennial mt-sDNA). Analysis 3 randomly assigned individuals to receive 1, 5, or 9 lifetime (9 = 100% adherence) mt-sDNA tests and 1, 5, or 9 to 26 (26 = 100% adherence) FIT tests. Outcomes are reported per 1000 individuals compared with no screening.ResultsEach screening strategy decreased CRC incidence and mortality versus no screening. In individuals screened between ages 50–75 and adherence ranging from 10%a-100%, the life-years gained (LYG) for triennial mt-sDNA ranged from 133.1–300.0, for annual FIT from 96.3–318.1, and for annual HSgFOBT from 99.8–320.6. At base-case imperfect adherence rates, mt-sDNA resulted in 19.1% more LYG versus FIT, 25.4% more LYG versus HSgFOBT, and generally had preferable efficiency ratios while offering the most LYG. Completion of at least 21 FIT tests is needed to reach approximately the same LYG achieved with 9 mt-sDNA tests.ConclusionsAdherence assumptions affect the conclusions of CRC screening microsimulations that are used to inform CRC screening guidelines. LYG from FIT and HSgFOBT are more sensitive to changes in adherence assumptions than mt-sDNA because they require more tests be completed for equivalent benefit. At imperfect adherence rates, mt-sDNA provides more LYG than FIT or HSgFOBT at an acceptable tradeoff in screening burden.

Systematic Review of Interventions to Increase Stool Blood Colorectal Cancer Screening in African Americans.

African Americans experience colorectal cancer (CRC) related disparities compared to other racial groups in the United States. African Americans are frequently diagnosed with CRC at a later stage, screening is underutilized, and mortality rates are highest in this group. This systematic review focused on intervention studies using stool blood CRC screening among African Americans in primary care and community settings. Given wide accessibility, low cost, and ease of dissemination of stool-based CRC screening tests, this review aims to determine effective interventions to improve participation rates. This systematic review included intervention studies published between January 1, 2000 and March 16, 2019. After reviewing an initial search of 650 studies, 11 studies were eventually included in this review. The included studies were studies conducted in community and clinical settings, using both inreach and outreach strategies to increase CRC screening. For each study, an unadjusted odds ratio (OR) for the CRC screening intervention compared to the control arm was calculated based on the data in each study to report effectiveness. The eleven studies together recruited a total of 3334 participants. The five studies using two-arm experimental designs ranged in effectiveness with ORs ranging from 1.1 to 13.0 using interventions such as mailed reminders, patient navigation, and tailored educational materials. Effective strategies to increase stool blood testing included mailed stool blood tests augmented by patient navigation, tailored educational materials, and follow-up calls or mailings to increase trust in the patient-provider relationship. More studies are needed on stool blood testing interventions to determine effectiveness in this population.

Stool Based Testing for Colorectal Cancer: an Overview of Available Evidence.

The goal of this review is to summarize stool-based testing for colorectal cancer (CRC). The key questions answered in this review were the advantages and limitations of each available stool-based test for CRC and to examine their comparative efficacy. Guaiac-based fecal occult blood testing (gFOBT) is no longer a relevant test for CRC screening. fecal immunochemical testing (FIT) tests, especially quantitative assays, are clearly a reliable stool-based test. Multitarget DNA (mtsDNA) stool testing may represent a viable option as well, although cost and test characteristics are yet fully defined. FIT and mtsDNA represent the options for stool-based CRC screening. In larger screening centers, quantitative FIT assays represent an attractive option for stool-based testing. Qualitative FIT has applicability in smaller centers. Although a large validation trial showed promising results for mtsDNA, further head-to-head trials with FIT will help define the ultimate role of mtsDNA. Ultimately, however, the best test for CRC screening is the one performed stool-based CRC screening as an initial or alternative option can increase participation in CRC screening.

Replacing the Guaiac Fecal Occult Blood Test With the Fecal Immunochemical Test Increases Proportion of Individuals Screened in a Large Healthcare Setting.

The most commonly used noninvasive test for colorectal cancer (CRC) screening has been the guaiac fecal occult blood test (gFOBT). The fecal immunochemical test (FIT) detects CRC and colorectal polyps with higher levels of sensitivity than the gFOBT, and may be more acceptable to patients. However, the FIT has not replaced the gFOBT in many clinical settings. We analyzed data from a large healthcare system that replaced the gFOBT with the FIT to determine the effects on CRC screening. We conducted a retrospective observational study of 7898 patients at the Veterans' Administration San Diego Healthcare System, 50-75 years old, who were offered stool-based CRC screening as part of primary care March 2014 through January 2015. Test orders and results were extracted from electronic health records; we performed manual reviews of colonoscopy and pathology reports for Veterans with positive results from the tests. Our primary outcome was test completion within 1 year of order; secondary outcomes were positive results and detection of advanced neoplasia by diagnostic colonoscopy. The primary analysis used an intention-to-screen approach, which included all patients with test orders; as-screened analyses were also performed. Among 7898 patients, 3236 had gFOBT and 4662 FIT orders. In the intention to screen analysis, a significantly higher proportion of subjects completed a FIT (42.6%) than a gFOBT (33.4%) (P< .001); advanced neoplasia was detected in a significantly higher proportion of subjects offered a FIT (0.79%) than a gFOBT (0.28%) (P= .003). The numbers needed to invite to achieve 1 additional completed test and identify 1 additional patient with advanced neoplasia were 11 and 196, respectively. In a retrospective study of patients at a Veterans' administration healthcare system, replacing the gFOBT with the FIT increased the proportion of patients who completed CRC screening. Replacement of the gFOBT with the FIT should be strongly considered by all healthcare systems.

Abstract IA16: Current and emerging molecular diagnostic assays for colorectal cancer

Abstract IA16: Current and emerging molecular diagnostic assays for colorectal cancer

55: Early Methylation of SYNE1 in Colorectal Cancer: Implications for Stool-Based Colorectal Cancer Screening

55: Early Methylation of SYNE1 in Colorectal Cancer: Implications for Stool-Based Colorectal Cancer Screening

As tests evolve and costs of cancer care rise: reappraising stool‐based screening for colorectal neoplasia

Colorectal cancer screening and treatment are rapidly evolving. Aims To reappraise stool-based colorectal cancer screening in light of changing test performance characteristics, lower test cost and increasing colorectal cancer care costs. Using a Markov model, we compared faecal DNA testing every 3 years, annual faecal occult blood testing or immunochemical testing, and colonoscopy every 10 years. In the base case, faecal occult blood testing and faecal immunochemical testing gained life-years/person and cost less than no screening. Faecal DNA testing version 1.1 at $300 (the current PreGen Plus test) gained 5323 life-years/100 000 persons at $16 900/life-year gained and faecal DNA testing version 2 (enhanced test) gained 5795 life-years/100 000 persons at $15 700/life-year gained vs. no screening. In the base case and most sensitivity analyses, faecal occult blood testing and faecal immunochemical testing were preferred to faecal DNA testing. Faecal DNA testing version 2 cost $100 000/life-year gained vs. faecal immunochemical testing when per-cycle adherence with faecal immunochemical testing was 22%. Faecal immunochemical testing with excellent adherence was superior to colonoscopy every 10 years. As novel biological therapies increase colorectal cancer treatment costs, faecal occult blood testing and faecal immunochemical testing could become cost-saving. The cost-effectiveness of faecal DNA testing compared with no screening has improved, but faecal occult blood testing and faecal immunochemical testing are preferred to faecal DNA testing when patient adherence is high. Faecal immunochemical testing may be comparable to colonoscopy every 10 years in persons adhering to yearly testing.