Improving Participation in Colorectal Cancer Screening: a Randomised Controlled Trial of Sequential Offers of Faecal then Blood Based Non-Invasive Tests

Circulating Tumor DNA in Addition to Fecal Immunochemical Test in a Dual-Test Colorectal Cancer Screening Approach

BACKGROUND

Early detection is paramount when reducing incidence and mortality of colorectal cancer (CRC). Current population-based screening programs primarily use fecal immunochemical test (FIT) to allocate individuals for colonoscopy although low specificity challenges colonoscopy capacities. We aimed to assess the potential of circulating tumor (ct)DNA markers for early CRC detection in a dual-test CRC screening approach among FIT positive individuals.

METHODS

Plasma samples from 774 FIT positive (≥100 ng Hemoglobin/mL) individuals from the Danish CRC screening program were analyzed for hypermethylated DNA in the genes Branched Chain Amino-acid Transaminase 1 (BCAT1), Ikaros-Family Zinc Finger transcription 1 (IKZF1), and Interferon Regulator Factor 4 (IRF4). Multivariate logistic regression models were generated adding the ctDNA markers and age to the FIT value. The dual-test approach was benchmarked to FIT at specific thresholds.

RESULTS

The dual-test approach improved CRC detection compared to the FIT alone (AUC of 87.2 [95% CI, 82.9-91.4] vs AUC of 72.5 [95% CI, 67.0-77.9]). This was also seen when adding advanced adenomas to the outcome resulting in AUCs of 71.8 [95% CI, 67.8-75.8] for the dual-test approach compared to 65.5 [95% CI, 61.3-69.7] for the FIT model alone. Benchmarking the dual-test approach at FIT cut-offs between 100 and 600 ng Hb/mL showed a potential for either reducing the colonoscopy requirement by up to 56% or increasing CRC detection by up to 28%.

CONCLUSIONS

As increasing FIT cutoff will decrease CRC detection rate, application of the ctDNA panel can increase the sensitivity and specificity in a dual-test approach among asymptomatic individuals.

Evaluation of a Multi-Gene Methylation Blood-Test for the Detection of Colorectal Cancer

Circulating tumour DNA biomarkers are an expanding field in oncology research that offer great potential but are currently often limited in value by overall cost. The aim of this study was to evaluate the efficacy of a novel multi-gene methylation blood test for the identification of colorectal cancer and throughout the spectrum of colorectal disease. Participants were recruited either prior to resection for known CRC or prior to screening colonoscopy after a positive faecal immunochemical test. Blood was collected from participants prior to their procedure being performed. The plasma was separated, and multiplex MethylLight droplet digital PCR was used to analyse for the presence of four methylated genes: SDC2, NPY, IKZF1 and SEPT9. A total of 537 participants underwent analysis. The SDC2/NPY genes showed a sensitivity of 33-54% and a specificity of 72-96%, whilst the IKZF1/SEPT9 genes showed a sensitivity of 19-42% and a specificity of 88-96%. Combining the two tests did not significantly increase the test accuracy. The sensitivity for advanced adenoma was 2-15%. There was a significant difference in the frequency of detectable methylation between the participants with CRC and those without CRC. However, neither the sensitivity nor the specificity was superior to current diagnostic screening tests.

Decision-making on colorectal cancer screening in Curaçao - interviews with the target population

BACKGROUND

During the first year of the population based colorectal cancer (CRC) screening program on Curaçao, about 20% of invitees participated. This study explored the target population's perceptions and awareness on CRC (screening), beliefs on the program provision, their preferences and information needs for informed decision-making.

METHODS

Semi-structured interviews with 23 individuals, who were not yet invited for CRC screening, were recorded, transcribed, coded and analyzed.

RESULTS

CRC (screening) was discussed in the context of personal health, where own responsibility and food were important. Cancer was perceived as an unpredictable disease that causes suffering and leads to death and was also associated with fear. Despite being aware of the program, most respondents were not familiar with the screening procedure. Provision of the screening program was regarded positively and as an opportunity to contribute to health improvement. This seemed related to the expressed trust in the Caribbean Prevention Center (program organizer). Respondents preferred to make independent decisions about CRC screening participation. A personal approach, visual aids and media were the preferred sources of information.

CONCLUSION

The results of our interviews suggest that it may be beneficial to provide information on CRC screening in Curaçao within the context of personal health. While including sensitivity to fears and respect for the autonomy of the target population. Finally, electronic media maybe useful in supporting informed decision-making.

To do or not to do - a survey study on factors associated with participating in the Danish screening program for colorectal cancer

Background

Screening programs for colorectal cancer (CRC) exist in many countries, and with varying participation rates. The present study aimed at identifying socio-demographic factors for accepting a cost-free screening offer for CRC in Denmark, and to study if more people would accept the screening offer if the present fecal test was replaced by a blood test.

Methods

We used a cross-sectional survey design based on a representative group of 6807 Danish citizens aged 50–80 years returning a fully answered web-based questionnaire with socio-demographic data added from national registries. Data were analyzed in STATA and based on bivariate analyses followed by regression models.

Results

Danes in general have a high level of lifetime participation (+ 80%) in the national CRC screening program. The results of the stepwise logistic regression model to predict CRC screening participation demonstrated that female gender, higher age, higher income, and moderate alcohol intake were positively associated with screening participation, whereas a negative association was observed for higher educational attainment, obesity, being a smoker, and higher willingness to take health risks. Of the 1026 respondents not accepting the screening offer, 61% were willing to reconsider their initial negative response if the fecal sampling procedure were replaced by blood sampling.

Conclusion

The CRC screening program intends to include the entire population within a certain at-risk age group. However, individual factors (e.g. sex, age obesity, smoking, risk aversity) appear to significantly affect willingness to participate in the screening program. From a preventive perspective, our findings indicate the need for a more targeted approach trying to reach these groups.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12913-020-06023-6.

What Factors Influence Non-Participation Most in Colorectal Cancer Screening? A Discrete Choice Experiment

Background and Objective

Non-participation in colorectal cancer (CRC) screening needs to be decreased to achieve its full potential as a public health strategy. To facilitate successful implementation of CRC screening towards unscreened individuals, this study aimed to quantify the impact of screening and individual characteristics on non-participation in CRC screening.

Methods

An online discrete choice experiment partly based on qualitative research was used among 406 representatives of the Dutch general population aged 55–75 years. In the discrete choice experiment, respondents were offered a series of choices between CRC screening scenarios that differed on five characteristics: effectiveness of the faecal immunochemical screening test, risk of a false-negative outcome, test frequency, waiting time for faecal immunochemical screening test results and waiting time for a colonoscopy follow-up test. The discrete choice experiment data were analysed in a systematic manner using random-utility-maximisation choice processes with scale and/or preference heterogeneity (based on 15 individual characteristics) and/or random intercepts.

Results

Screening characteristics proved to influence non-participation in CRC screening (21.7–28.0% non-participation rate), but an individual’s characteristics had an even higher impact on CRC screening non-participation (8.4–75.5% non-participation rate); particularly the individual’s attitude towards CRC screening followed by whether the individual had participated in a cancer screening programme before, the decision style of the individual and the educational level of the individual. Our findings provided a high degree of confidence in the internal–external validity.

Conclusions

This study showed that although screening characteristics proved to influence non-participation in CRC screening, a respondent’s characteristics had a much higher impact on CRC screening non-participation. Policy makers and physicians can use our study insights to improve and tailor their communication plans regarding (CRC) screening for unscreened individuals.

lncRNA UASR1 sponges miR-107 in colorectal cancer to upregulate oncogenic CDK8 and promote cell proliferation

lncRNA UASR1 (UASR1) has been characterized as an oncogenic lncRNA in breast cancer. UASR1 was predicted to interact with miR-107, which serves tumor suppressive roles mainly by targeting CDK8. The present study was performed to investigate the interactions among UASR1, miR-107 and CDK8 in colorectal cancer (CRC). A total of 62 patients with CRC, including 40 males and 22 females (age range, 38-67 years; mean age, 57.2±7.6 years) were enrolled at the Second Hospital of Shandong University between July 2012 and July 2014. The expression of UASR1 in tissues and cells were detected by reverse transcription-quantitative polymerase chain reaction. The interaction between UASR1 and miR-107 was investigated by performing dual luciferase activity assay, and the effects of overexpression of UASR1, miR-107 and CDK8 on the proliferation of CR4 cells were analyzed by performing cell proliferation analysis. It was observed that UASR1 is upregulated in CRC and its high expression levels predicted poor survival in patients with CRC. RNA-RNA interaction prediction demonstrated that UASR1 may interact with miR-107. In CRC cells, overexpression of UASR1 and miR-107 did not affect each other. However, the expression of CDK8, a target of miR-107, was upregulated following overexpression of UASR1. Notably, overexpression of UASR1 decreased the inhibitory effects of miR-107 on cell proliferation and the expression of CDK8. Therefore, UASR1 may sponge miR-107 to upregulate oncogenic CDK8, thereby promoting CRC cell proliferation.

Uptake of a colorectal cancer screening blood test in people with elevated risk for cancer who cannot or will not complete a faecal occult blood test

Participation rates in colorectal cancer (CRC) screening programmes using faecal occult blood tests (FOBTs) are low. Nonparticipation is commonly attributed to psychosocial factors, but some medical conditions also prevent screening. These barriers might be partially overcome if a blood test for CRC screening was available. This study determined whether people who had always declined screening by FOBT would participate if offered a blood test. An audit of registrants within a personalized CRC screening programme was undertaken to determine the reasons for regular nonparticipation in FOBT. Consistent nonparticipants (n=240) were randomly selected and invited for CRC screening with a blood test. Demographic characteristics and the reasons for prior FOBT nonparticipation were collected by means of a questionnaire. Nonparticipation in the screening programme could be classified as either behavioural (8.6%), with consistent noncompliance, or due to medical contraindications (8.5%), which included chronic rectal bleeding, being deemed unsuitable by a health professional, and needing personal assistance. Blood test uptake was 25%, with participation in the medical contraindications group greater than that in the behavioural group (43 vs. 12%, P<0.001). Reported behavioural reasons for nonparticipation in faecal immunochemical test included procrastination and dislike of the test, but these were not associated with blood test uptake (P>0.05). There is a subgroup of the community who have medical reasons for nonparticipation in CRC screening with FOBT but will participate if offered a blood test. The option of a blood test does not, however, improve uptake in those who admit to behavioural reasons for noncompliance with screening.

Effects of subitems in the colorectal cancer screening protocol on the Chinese colorectal cancer screening program: an analysis based on natural community screening results

Background

To date, no single colorectal cancer (CRC) screening strategy has been determined to be applicable worldwide. In China, a CRC screening protocol that combines double fecal immunochemical tests (FITs) and a high-risk factor questionnaire (HRFQ) as the first stage of screening and colonoscopy as the second stage of screening (scenario A) was adapted by the Chinese Ministry of Health in 2006. However, applying this CRC screening protocol nationally remains difficult because its effectiveness and convenience are controversial. This study evaluated the effects of subitems of the CRC screening protocol in China.

Methods

CRC screening results (scenario A) from Jiashan County, China, (2007–2009) were used to analyze the detection rates of CRC and advanced neoplasms as well as the cost-effectiveness of the protocol. Scenario A was divided into scenarios B–G (by selecting some items at the first stage of screening) for analysis.

Results

Compared with scenario A, removing the whole HRFQ (scenario F) reduced advanced neoplasm and adenoma detections by 29.8 and 41.2%, respectively, whereas the whole HRFQ accounted for 10.1% of the total screening cost. Removing FITs (scenario G) reduced CRC, advanced neoplasm and adenoma detections by 71.8, 56.9 and 47.7%, respectively, and the costs per case of CRC and advanced neoplasm were 82.0 and 19.1% higher, respectively, than those in scenario A.

In scenarios B–E (deleting some high-risk factor questions on the HRFQ), the odds ratios (ORs) of the detection rates and costs per CRC, advanced neoplasm, adenoma, and neoplasm case were near 1.00.

Scenarios C and D reduced the high-risk population and total screening costs by less than 6.0 and 4.1%, respectively. Scenarios E and B (FITs and a personal history of cancer or colorectal adenoma were reserved) reduced the high-risk population by 17.6 and 24.2% and the total screening costs by 11.2 and 15.4%, respectively, while the numbers of CRC cases were not missed, and advanced neoplasms detected decreased by only 5 and 11%, respectively.

Conclusion

The results of this study demonstrate that FITs and a personal history of colorectal adenoma are the most effective items in the Chinese CRC screening protocol.

Review of Blood-Based Colorectal Cancer Screening: How Far Are Circulating Cell-Free DNA Methylation Markers From Clinical Implementation?

Colorectal cancer (CRC) is a leading cause of cancer related deaths worldwide, and late stages (III-IV) in particular have low 5-year survival rates. Stage shifting by CRC screening programs has proven effective by decreasing morbidity and mortality and in many countries national CRC screening programs have been implemented. Currently, European, Asian, and American authorities recommend screening for CRC using fecal occult blood testing, sigmoidoscopy, or colonoscopy. Because these approaches all have weaknesses (eg, poor compliance, high costs, test invasiveness), much effort has been put into the development of alternative screening approaches, many of which are blood-based. Blood-based strategies especially present the advantages of minimally invasiveness compared to endoscopies and an expectantly higher compliance rate compared to stool-based tests. The last decades have seen many discovery studies identifying promising blood-based biomarkers of CRC; however, common to all of these markers is that their clinical usefulness remains evasive. At present only one blood-based CRC screening marker has been approved in the United States. The aim of this review is to discuss the development of blood-based cell-free DNA methylation marker candidates for CRC screening. On the basis of a methodical literature search, the past, present, and future of cell-free DNA screening markers for CRC are revised and discussed. Resource limitations and technical challenges related to sensitivity and specificity measurements keep many markers at bay. Possible solutions to these problems are offered to enable markers to benefit future screening participants.

The impact of sample type and procedural attributes on relative acceptability of different colorectal cancer screening regimens

OBJECTIVE

In Australia and other countries, participation in colorectal cancer (CRC) screening using fecal occult blood testing is low. Previous research suggests that fecal sampling induces disgust, so approaches not involving feces may increase participation. This study aimed to determine population preferences for CRC screening tests that utilize different sample collections (stool, blood, and saliva) and the extent to which specific attributes (convenience, performance, and cost) impact this preference.

MATERIALS AND METHODS

People aged 50-74 years completed a survey. Preference for screening for CRC through stool, blood, and saliva was judged through ranking of preference and attributes critical to preference and confirmed via a discrete choice experiment (DCE) where test attributes were described as varying by performance, cost, and sample type. Participants also completed a measure of aversion to sample type.

RESULTS

A total of 1,282 people participated in the survey. The DCE and ranking exercise confirmed that all test attributes had a statistically significant impact on respondents' preferences (P < 0.001). Blood and saliva were equally preferred over stool; however, test performance was the most influential attribute. In multivariable analyses, those who preferred blood to stool collection exhibited higher aversion to fecal (OR = 1.17; P ≤ 0.001) and saliva (OR = 1.06; P ≤ 0.05) sampling and perceived that they had less time for home sample collection (OR = 0.72, P ≤ 0.001). Those who preferred saliva to stool had higher aversion to fecal (OR = 1.15; P ≤ 0.001) and blood (OR = 1.06, P ≤ 0.01) sampling and less time for home sample collection (OR = 0.81, P ≤ 0.5).

CONCLUSION

Aversion to sample type and perceived inconvenience of sample collection are significant drivers of screening preference. While blood and saliva sampling were the most preferred methods, test performance was the most important attribute of a screening test, regardless of sample type. Efforts to increase CRC screening participation should focus on a test, or combination of tests, that combines the attributes of high performance, low aversion, and convenience of use.

Prospective evaluation of 64 serum autoantibodies as biomarkers for early detection of colorectal cancer in a true screening setting

Novel blood-based screening tests are strongly desirable for early detection of colorectal cancer (CRC). We aimed to identify and evaluate autoantibodies against tumor-associated antigens as biomarkers for early detection of CRC. 380 clinically identified CRC patients and samples of participants with selected findings from a cohort of screening colonoscopy participants in 2005–2013 (N=6826) were included in this analysis. Sixty-four serum autoantibody markers were measured by multiplex bead-based serological assays. A two-step approach with selection of biomarkers in a training set, and validation of findings in a validation set, the latter exclusively including participants from the screening setting, was applied. Anti-MAGEA4 exhibited the highest sensitivity for detecting early stage CRC and advanced adenoma. Multi-marker combinations substantially increased sensitivity at the price of a moderate loss of specificity. Anti-TP53, anti-IMPDH2, anti-MDM2 and anti-MAGEA4 were consistently included in the best-performing 4-, 5-, and 6-marker combinations. This four-marker panel yielded a sensitivity of 26% (95% CI, 13–45%) for early stage CRC at a specificity of 90% (95% CI, 83–94%) in the validation set. Notably, it also detected 20% (95% CI, 13–29%) of advanced adenomas. Taken together, the identified biomarkers could contribute to the development of a useful multi-marker blood-based test for CRC early detection.

Validation of a Circulating Tumor-Derived DNA Blood Test for Detection of Methylated BCAT1 and IKZF1 DNA

BACKGROUND

Colvera™ is a test that detects circulating tumor-derived DNA in patients with colorectal cancer by assaying for the presence of methylated BCAT1 and IKZF1 in blood. This study describes the analytical and clinical performance characteristics of the test.

METHODS

Validation was performed in accordance with ISO15189 and National Pathology Accreditation Advisory Council requirements. Spiked samples including 264 plasma and 120 buffer samples were randomized, divided into 8 batches of 48 samples, and processed over 8 days using 2 equipment lines (each line consisting of a QIAsymphony SP/AS, QIACube HT, and LC480); 2 reagent batches; and 2 operators to determine limit of detection, selectivity/specificity, precision, reproducibility, ruggedness, and susceptibility to commonly known interfering substances. Clinical performance was validated by assaying 222 archived plasma samples from subjects (n = 26 with cancer) enrolled in a previous prospective trial.

RESULTS

The limit of detection for Colvera was 12.6 pg/mL (95% CI, 8.6-23.9 pg/mL), which equates to 2 diploid genome copies per milliliter plasma. No statistically significant difference was determined between testing days (n = 8), instrumentation, operators, or reagent batches in precision studies for the methylation-specific assays. The assay performance was unaffected by 9 commonly known interference substances, variations in bisulfite conversion, or quantitative PCR settings (cycling temperatures, incubation times, and oligonucleotide concentrations). For this clinical cohort, sensitivity and specificity estimates for Colvera were 73.1% (19 of 26; 95% CI, 52.2-88.4) and 89.3% (175 of 196; 95% CI, 84.1-93.2), respectively.

CONCLUSION

Colvera is a robust test and suitable for detection of circulating tumor-derived DNA by measuring levels of methylated BCAT1 and IKZF1 in human blood plasma.

Colorectal Cancer Screening: Recommendations for Physicians and Patients From the U.S. Multi-Society Task Force on Colorectal Cancer

This document updates the colorectal cancer (CRC) screening recommendations of the U.S. Multi-Society Task Force of Colorectal Cancer (MSTF), which represents the American College of Gastroenterology, the American Gastroenterological Association, and The American Society for Gastrointestinal Endoscopy. CRC screening tests are ranked in 3 tiers based on performance features, costs, and practical considerations. The first-tier tests are colonoscopy every 10 years and annual fecal immunochemical test (FIT). Colonoscopy and FIT are recommended as the cornerstones of screening regardless of how screening is offered. Thus, in a sequential approach based on colonoscopy offered first, FIT should be offered to patients who decline colonoscopy. Colonoscopy and FIT are recommended as tests of choice when multiple options are presented as alternatives. A risk-stratified approach is also appropriate, with FIT screening in populations with an estimated low prevalence of advanced neoplasia and colonoscopy screening in high prevalence populations. The second-tier tests include CT colonography every 5 years, the FIT-fecal DNA test every 3 years, and flexible sigmoidoscopy every 5 to 10 years. These tests are appropriate screening tests, but each has disadvantages relative to the tier 1 tests. Because of limited evidence and current obstacles to use, capsule colonoscopy every 5 years is a third-tier test. We suggest that the Septin9 serum assay (Epigenomics, Seattle, Wash) not be used for screening. Screening should begin at age 50 years in average-risk persons, except in African Americans in whom limited evidence supports screening at 45 years. CRC incidence is rising in persons under age 50, and thorough diagnostic evaluation of young persons with suspected colorectal bleeding is recommended. Discontinuation of screening should be considered when persons up to date with screening, who have prior negative screening (particularly colonoscopy), reach age 75 or have <10 years of life expectancy. Persons without prior screening should be considered for screening up to age 85, depending on age and comorbidities. Persons with a family history of CRC or a documented advanced adenoma in a first-degree relative age <60 years or 2 first-degree relatives with these findings at any age are recommended to undergo screening by colonoscopy every 5 years, beginning 10 years before the age at diagnosis of the youngest affected relative or age 40, whichever is earlier. Persons with a single first-degree relative diagnosed at ≥60 years with CRC or an advanced adenoma can be offered average-risk screening options beginning at age 40 years.

Colorectal Cancer Screening: Recommendations for Physicians and Patients from the U.S. Multi-Society Task Force on Colorectal Cancer

This document updates the colorectal cancer (CRC) screening recommendations of the U.S. Multi-Society Task Force of Colorectal Cancer (MSTF), which represents the American College of Gastroenterology, the American Gastroenterological Association, and The American Society for Gastrointestinal Endoscopy. CRC screening tests are ranked in 3 tiers based on performance features, costs, and practical considerations. The first-tier tests are colonoscopy every 10 years and annual fecal immunochemical test (FIT). Colonoscopy and FIT are recommended as the cornerstones of screening regardless of how screening is offered. Thus, in a sequential approach based on colonoscopy offered first, FIT should be offered to patients who decline colonoscopy. Colonoscopy and FIT are recommended as tests of choice when multiple options are presented as alternatives. A risk-stratified approach is also appropriate, with FIT screening in populations with an estimated low prevalence of advanced neoplasia and colonoscopy screening in high prevalence populations. The second-tier tests include CT colonography every 5 years, the FIT-fecal DNA test every 3 years, and flexible sigmoidoscopy every 5 to 10 years. These tests are appropriate screening tests, but each has disadvantages relative to the tier 1 tests. Because of limited evidence and current obstacles to use, capsule colonoscopy every 5 years is a third-tier test. We suggest that the Septin9 serum assay (Epigenomics, Seattle, Wash) not be used for screening. Screening should begin at age 50 years in average-risk persons, except in African Americans in whom limited evidence supports screening at 45 years. CRC incidence is rising in persons under age 50, and thorough diagnostic evaluation of young persons with suspected colorectal bleeding is recommended. Discontinuation of screening should be considered when persons up to date with screening, who have prior negative screening (particularly colonoscopy), reach age 75 or have <10 years of life expectancy. Persons without prior screening should be considered for screening up to age 85, depending on age and comorbidities. Persons with a family history of CRC or a documented advanced adenoma in a first-degree relative age <60 years or 2 first-degree relatives with these findings at any age are recommended to undergo screening by colonoscopy every 5 years, beginning 10 years before the age at diagnosis of the youngest affected relative or age 40, whichever is earlier. Persons with a single first-degree relative diagnosed at ≥60 years with CRC or an advanced adenoma can be offered average-risk screening options beginning at age 40 years.

Protocol Outlines for Parts 1 and 2 of the Prospective Endoscopy III Study for the Early Detection of Colorectal Cancer: Validation of a Concept Based on Blood Biomarkers

BACKGROUND

Programs for population screening of colorectal cancer (CRC) have been implemented in several countries with fecal immunochemical testing (FIT) as the preferred platform. However, the major obstacle for a feces-based testing method is the limited compliance that reduces the clinical sensitivity for detection of participants with non-symptomatic CRC. Therefore, research approaches have been initiated to develop screening concepts based on biomarkers in blood. Preliminary results show that protein, genetic, epigenetic, and metabolomic components may be valuable in blood-based screening concepts, particularly when combinations of the various components appear to lead to significant improvements.

OBJECTIVES

The protocol described in this paper focuses on the validation of concepts based on biomarkers in blood in a major population screened by FIT.

METHODS

In Part 1, participants will be identified and included through the Danish CRC Screening Program comprising initial FIT and subsequent colonoscopy to those with a positive result. Blood samples will be collected from 8000 FIT-positive participants, who are offered subsequent colonoscopy. Findings and interventions at colonoscopy together with personal data including co-morbidity will be recorded. Blood samples and data will also be collected from 6000 arbitrarily chosen participants with negative FIT. In Part 2, blood samples and data will be collected from 30,000 FIT-negative participants three times within 4 years. The blood samples will be analyzed using various in-house and commercially available manual and automated analysis platforms.

RESULTS

We anticipate Part 1 to terminate late August 2016 and Part 2 to terminate late September 2022. The results from Parts 1 and 2 will be presented within 12 to 18 months from termination.

CONCLUSIONS

The purpose of this study is to improve the efficacy of identifying participants with neoplastic bowel lesions, to identify false negative participants, to identify participants at risk of interval neoplastic lesions, to improve the compliance in screening sessions, and to establish guidelines for out-patient follow-up of at-risk participants based on combinations of blood-based biomarkers.