Comparative Effectiveness and Cost Effectiveness of a Multitarget Stool DNA Test to Screen for Colorectal Neoplasia

Comparative Effectiveness and Cost-Effectiveness of Colorectal Cancer Screening With Blood-Based Biomarkers (Liquid Biopsy) vs Fecal Tests or Colonoscopy

BACKGROUND & AIMS

Colorectal cancer (CRC) screening is highly effective but underused. Blood-based biomarkers (liquid biopsy) could improve screening participation.

METHODS

Using our established Markov model, screening every 3 years with a blood-based test that meets minimum Centers for Medicare & Medicaid Services' thresholds (CMSmin) (CRC sensitivity 74%, specificity 90%) was compared with established alternatives. Test attributes were varied in sensitivity analyses.

RESULTS

CMSmin reduced CRC incidence by 40% and CRC mortality by 52% vs no screening. These reductions were less profound than the 68%-79% and 73%-81%, respectively, achieved with multi-target stool DNA (Cologuard; Exact Sciences) every 3 years, annual fecal immunochemical testing (FIT), or colonoscopy every 10 years. Assuming the same cost as multi-target stool DNA, CMSmin cost $28,500/quality-adjusted life-year gained vs no screening, but FIT, colonoscopy, and multi-target stool DNA were less costly and more effective. CMSmin would match FIT's clinical outcomes if it achieved 1.4- to 1.8-fold FIT's participation rate. Advanced precancerous lesion (APL) sensitivity was a key determinant of a test's effectiveness. A paradigm-changing blood-based test (sensitivity >90% for CRC and 80% for APL; 90% specificity; cost ≤$120-$140) would be cost-effective vs FIT at comparable participation.

CONCLUSIONS

CMSmin could contribute to CRC control by achieving screening in those who will not use established methods. Substituting blood-based testing for established effective CRC screening methods will require higher CRC and APL sensitivities that deliver programmatic benefits matching those of FIT. High APL sensitivity, which can result in CRC prevention, should be a top priority for screening test developers. APL detection should not be penalized by a definition of test specificity that focuses on CRC only.

Screening for Colorectal Cancer

Colorectal cancer remains the third leading cause of cancer death in the United States. Colorectal cancer screening allows for prevention and early detection of precancerous and cancerous lesions, and screening has been shown to be effective in preventing colorectal cancer deaths. Screening recommendations vary by patient risk profile. A variety of screening modalities exist.

Explorative cost-effectiveness analysis of colorectal cancer recurrence detection with next-generation sequencing liquid biopsy in Spain, France, and Germany

Background

Next-generation sequencing liquid biopsy (NGS-LB) for colorectal cancer (CRC) detection and surveillance remains an expensive technology as economies of scale have not yet been realized. Nevertheless, the cost of sequencing has decreased while sensitivity has increased, raising the question of whether cost-effectiveness (CE) has already been achieved from the perspective of European healthcare systems.

Objectives

This health economic (HE) modeling study explores the CE of NGS-LB for CRC based on direct treatment costs compared to standard care without liquid biopsy in Spain, France, and Germany.

Methods

A structured literature search was used to collect evidence from 2009 to 2020 on the stage-dependent quality of life (quality-adjusted life-years, QALY), efficacy, and total direct treatment costs (TDC) of NGS-LB. A decision-analytic Markov model was developed. Over the remaining lifetime, cumulative life expectancy (LE), TDC, and QALYs were calculated for 60-year-old men and women in CRC stage III with different assumed effects of NGS-LB of 1% or 3% on improved survival and reduced stage progression, respectively.

Results

The use of NGS-LB increases LE by 0.19 years in Spanish men (France: 0.19 years, Germany: 0.13 years) and by 0.21 years in Spanish women (France: 0.21 years, Germany: 0.14 years), respectively. The 3% discounted cost per QALY gained was 35,571.95 € for Spanish men (France: 31,705.15 €, Germany: 37,537.68 €) and 35,435.71 € for Spanish women (France: 31,295.57 €, Germany: 38,137.08 €) in the scenario with 3% improved survival and reduced disease progression. Compared to the other two countries, Germany has by far the highest TDC, which can amount to >80k euros in the last treatment year.

Conclusion

In this explorative HE modeling study, NGS-LB achieves generally accepted CE levels in CRC treatment from the health system perspective in three major European economies under assumptions of small improvements in cancer recurrence and survival. Confirmation of these findings through clinical trials is encouraged.

Cost-Utility Analysis of Berberine Chemoprevention for Colorectal Cancer After Polypectomy

Background Chemoprevention, such as berberine, has been developed as an alternative or complementary strategy to colonoscopy surveillance and has shown promise in reducing the morbidity and mortality of colorectal cancer. This study aims to evaluate the cost-effectiveness of berberine for postpolypectomy patients from the US third-party payer. Methods A Markov microsimulation model was developed to compare the cost and efficacy of berberine to no intervention, colonoscopy, and the combination of berberine and colonoscopy in postpolypectomy patients. Results After simulating 1 million patients, the study found that colonoscopy alone had a mean cost of $16,391 and mean quality-adjusted life-years (QALYs) of 16.03 per patient, whereas adding berberine slightly reduced the mean cost to $15,609 with a mean QALY of 16.05, making it a dominant strategy. Berberine therapy alone was less effective than colonoscopy alone, with a higher mean cost of $37,480 and a mean QALY of 15.32 per patient. However, berberine therapy was found to be a dominant strategy over no intervention. Conclusions Adding berberine to colonoscopy is the most cost-saving and effective approach for postpolypectomy patients. For patients who refuse or have limited access to colonoscopy, berberine alone is likely to be a dominant strategy compared to no intervention.

Colonoscopy vs the Fecal Immunochemical Test: Which is Best?

Although there is no debate around the effectiveness of colorectal cancer screening in reducing disease burden, there remains a question regarding the most effective and cost-effective screening modality. Current United States guidelines present a panel of options that include the 2 most commonly used modalities, colonoscopy and stool testing with the fecal immunochemical test (FIT). Large-scale comparative effectiveness trials comparing colonoscopy and FIT for colorectal cancer outcomes are underway, but results are not yet available. This review will separately state the "best case" for FIT and colonoscopy as the screening tool of first choice. In addition, the review will examine these modalities from a health economics perspective to provide the reader further context about the relative advantages of these commonly used tests.

Colorectal cancer screening: A review of current knowledge and progress in research

Colorectal cancer (CRC) is one of the most prevalent malignancies worldwide, being the third most commonly diagnosed malignancy and the second leading cause of cancer-related deaths globally. Despite the progress in screening, early diagnosis, and treatment, approximately 20%-25% of CRC patients still present with metastatic disease at the time of their initial diagnosis. Furthermore, the burden of disease is still expected to increase, especially in individuals younger than 50 years old, among whom early-onset CRC incidence has been increasing. Screening and early detection are pivotal to improve CRC-related outcomes. It is well established that CRC screening not only reduces incidence, but also decreases deaths from CRC. Diverse screening strategies have proven effective in decreasing both CRC incidence and mortality, though variations in efficacy have been reported across the literature. However, uncertainties persist regarding the optimal screening method, age intervals and periodicity. Moreover, adherence to CRC screening remains globally low. In recent years, emerging technologies, notably artificial intelligence, and non-invasive biomarkers, have been developed to overcome these barriers. However, controversy exists over the actual impact of some of the new discoveries on CRC-related outcomes and how to effectively integrate them into daily practice. In this review, we aim to cover the current evidence surrounding CRC screening. We will further critically assess novel approaches under investigation, in an effort to differentiate promising innovations from mere novelties.

Sessile serrated polyp detection rates after fecal immunochemical test or multitarget stool DNA test: Systematic review and meta-analysis

Background and study aims Published studies report a higher adenoma detection rate (ADR) for FIT-DNA as compared with FIT. Data are less replete about the performance of stool-based tests for sessile serrated polyp (SSP) detection. We performed a meta-analysis to evaluate the performance of FIT and FIT-DNA testing for SSP detection rate (SSPDR) in patients undergoing colonoscopy for follow up of positive noninvasive tests. Methods A comprehensive literature search of multiple databases (until September 2022) was performed to identify studies reporting SSPDR in patients with positive FIT or FIT-DNA tests. The outcome was overall colonoscopy detection of any SSPs and advanced serrated polyps (ASP: SSP ≥ 10 mm and/or dysplasia). Results Included were 482,405 patients (52.4% females) with a mean age of 62.3 ± 4.4 years from 23 studies. The pooled SSPDR for all positive stool-based tests was 5.3% and higher for FIT-DNA (15.0%, 95% confidence interval [CI] 8.3-25.7) versus FIT (4.1%, 95% CI 3.0-5.6; P = 0.0002). The overall pooled ASP detection rate was 1.4% (95% CI 0.81-2.3) and higher for FIT-DNA (3.8 %, 95% CI 1.7-8.6) compared with FIT (0.71%, 95% CI 0.36-1.4; P <0.01). SSPDR with FIT-DNA was also significantly higher than FIT when the FIT cutoff was >10 ug/g and in FIT-positive patients in studies conducted in North America ( P <0.05). Conclusions FIT-DNA outperformed FIT in both SSP and ASP detection including FIT with a lower threshold cutoff of >10 ug/g. Further comparative studies are needed to assess the impact of our findings on colorectal cancer reduction.

Colorectal cancer screening at age 45 years in Israel: Cost-effectiveness and global implications

BACKGROUND

Colorectal cancer (CRC) incidence at ages <50 years is increasing worldwide. Screening initiation was lowered to 45 years in the United States. The cost-effectiveness of initiating CRC screening at 45 years in Israel was assessed with the aim of informing national policy and addressing internationally relevant questions.

METHODS

A validated CRC screening model was calibrated to Israeli data and examined annual fecal immunochemical testing (FIT) or colonoscopy every 10 years from 45 to 74 years (FIT45-74 or Colo45-74) versus from 50 to 74 years (FIT50-74 or Colo50-74). The addition of a fourth colonoscopy at 75 years was explored, subanalyses were performed by sex/ethnicity, and resource demands were estimated.

RESULTS

FIT50-74 and Colo50-74 reduced CRC incidence by 57% and 70% and mortality by 70% and 77%, respectively, versus no screening, with greater absolute impact in Jews/Other versus Arabs but comparable relative impact. FIT45-74 further reduced CRC incidence and mortality by an absolute 3% and 2%, respectively. With Colo45-74 versus Colo50-74, CRC cases and deaths increased slightly as three colonoscopies per lifetime shifted to 5 years earlier but mean quality-adjusted life-years gained (QALYGs) per person increased. FIT45-74 and Colo45-74 cost 23,800-53,900 new Israeli shekels (NIS)/QALYG and 110,600-162,700 NIS/QALYG, with the lowest and highest values among Jewish/Other men and Arab women, respectively. A fourth lifetime colonoscopy cost 48,700 NIS/QALYG. Lowering FIT initiation to 45 years with modest participation required 19,300 additional colonoscopies in the first 3 years.

CONCLUSIONS

Beginning CRC screening at 45 years in Israel is projected to yield modest clinical benefits at acceptable costs per QALYG. Despite different estimates by sex/ethnicity, a uniform national policy is favored. These findings can inform Israeli guidelines and serve as a case study internationally.

Next-Generation Screening for Colorectal Cancer, an Incremental Approach to a Global Disease

New screening tests for early detection of colorectal cancer and its precursors are rapidly emerging with the focus on noninvasive tests which can be used in both structured opportunistic and population-based organized screening programs. Novel technologies are identifying new combinations of promising markers. Conducting large prospective clinical trials of efficacy requires very large numbers of subjects constituting intended-use populations. These trials are often preceded by studies using smaller numbers of "convenience" samples to derive panels of relevant markers and algorithms to combine them and define what constitutes a positive test. The article by Gagrat and colleagues in this issue reports results from one such study designed to yield a "next-generation" multitargeted (mt-sDNA) stool test. This report exemplifies the advantages and limitations of this approach. See related article by Gagrat et al., p. 119.

Differential impact of test performance characteristics on burden-to-benefit tradeoffs for blood-based colorectal cancer screening: A microsimulation analysis

OBJECTIVES

To inform the development and evaluation of new blood-based colorectal cancer (CRC) screening tests satisfying minimum United States (US) coverage criteria, we estimated the impact of the different test performance characteristics on long-term testing benefits and burdens.

METHODS

A novel CRC-Microsimulation of Adenoma Progression and Screening (CRC-MAPS) model was developed, validated, then used to assess different screening tests for CRC. We compared multiple, hypothetical blood-based CRC screening tests satisfying minimum coverage criteria of 74% CRC sensitivity and 90% specificity, to measure how changes in a test's CRC sensitivity, specificity, and adenoma sensitivity (sizes 1-5 mm, 6-9 mm, ≥10 mm) affect total number of colonoscopies (COL), CRC incidence reduction (IR), CRC mortality reduction (MR), and burden-to-benefit ratios (incremental COLs per percentage-point increase in IR or MR).

RESULTS

A blood test meeting minimum US coverage criteria for performance characteristics resulted in 1576 lifetime COLs per 1000 individuals, 46.7% IR and 59.2% MR compared to no screening. Tests with increased CRC sensitivity of 99% ( + 25%) vs. increased ≥10 mm adenoma sensitivity of 13.6% ( + 3.6%) both yielded the same MR, 62.7%. Test benefits improved the most with increases in all-size adenoma sensitivity, then size-specific adenoma sensitivities, then specificity and CRC sensitivity, while increases in specificity or ≥10 mm adenoma sensitivity resulted in the most favorable burden-to-benefit tradeoffs (ratios <11.5).

CONCLUSIONS

Burden-to-benefit ratios for blood-based CRC screening tests differ by performance characteristic, with the most favorable tradeoffs resulting from improvements in specificity and ≥10 mm adenoma sensitivity.

AGA Clinical Practice Update on Risk Stratification for Colorectal Cancer Screening and Post-Polypectomy Surveillance: Expert Review

DESCRIPTION

Since the early 2000s, there has been a rapid decline in colorectal cancer (CRC) mortality, due in large part to screening and removal of precancerous polyps. Despite these improvements, CRC remains the second leading cause of cancer deaths in the United States, with approximately 53,000 deaths projected in 2023. The aim of this American Gastroenterological Association (AGA) Clinical Practice Update Expert Review was to describe how individuals should be risk-stratified for CRC screening and post-polypectomy surveillance and to highlight opportunities for future research to fill gaps in the existing literature.

METHODS

This Expert Review was commissioned and approved by the American Gastroenterological Association (AGA) Institute Clinical Practice Updates Committee (CPUC) and the AGA Governing Board to provide timely guidance on a topic of high clinical importance to the AGA membership, and underwent internal peer review by the CPUC and external peer review through standard procedures of Gastroenterology. These Best Practice Advice statements were drawn from a review of the published literature and from expert opinion. Because systematic reviews were not performed, these Best Practice Advice statements do not carry formal ratings regarding the quality of evidence or strength of the presented considerations. Best Practice Advice Statements BEST PRACTICE ADVICE 1: All individuals with a first-degree relative (defined as a parent, sibling, or child) who was diagnosed with CRC, particularly before the age of 50 years, should be considered at increased risk for CRC. BEST PRACTICE ADVICE 2: All individuals without a personal history of CRC, inflammatory bowel disease, hereditary CRC syndromes, other CRC predisposing conditions, or a family history of CRC should be considered at average risk for CRC. BEST PRACTICE ADVICE 3: Individuals at average risk for CRC should initiate screening at age 45 years and individuals at increased risk for CRC due to having a first-degree relative with CRC should initiate screening 10 years before the age at diagnosis of the youngest affected relative or age 40 years, whichever is earlier. BEST PRACTICE ADVICE 4: Risk stratification for initiation of CRC screening should be based on an individual's age, a known or suspected predisposing hereditary CRC syndrome, and/or a family history of CRC. BEST PRACTICE ADVICE 5: The decision to continue CRC screening in individuals older than 75 years should be individualized, based on an assessment of risks, benefits, screening history, and comorbidities. BEST PRACTICE ADVICE 6: Screening options for individuals at average risk for CRC should include colonoscopy, fecal immunochemical test, flexible sigmoidoscopy plus fecal immunochemical test, multitarget stool DNA fecal immunochemical test, and computed tomography colonography, based on availability and individual preference. BEST PRACTICE ADVICE 7: Colonoscopy should be the screening strategy used for individuals at increased CRC risk. BEST PRACTICE ADVICE 8: The decision to continue post-polypectomy surveillance for individuals older than 75 years should be individualized, based on an assessment of risks, benefits, and comorbidities. BEST PRACTICE ADVICE 9: Risk-stratification tools for CRC screening and post-polypectomy surveillance that emerge from research should be examined for real-world effectiveness and cost-effectiveness in diverse populations (eg, by race, ethnicity, sex, and other sociodemographic factors associated with disparities in CRC outcomes) before widespread implementation.

Diagnostic value of methylated branched chain amino acid transaminase 1/IKAROS family zinc finger 1 for colorectal cancer

BACKGROUND

The diagnostic value of combined methylated branched chain amino acid transaminase 1 (BCAT1)/IKAROS family zinc finger 1 (IKZF1) in plasma for colorectal cancer (CRC) has been explored since 2015. Recently, several related studies have published their results and showed its diagnostic efficacy.

AIM

To analyze the diagnostic value of methylated BCAT1/IKZF1 in plasma for screening and postoperative follow-up of CRC.

METHODS

The candidate studies were identified by searching the PubMed, Embase, Cochrane Library, CNKI, and Wanfang databases from May 31, 2003 to June 1, 2023. Sensitivity, specificity, and diagnostic accuracy were calculated by merging ratios or means.

RESULTS

Twelve eligible studies were included in the analysis, involving 6561 participants. The sensitivity of methylated BCAT1/IKZF1 in plasma for CRC diagnosis was 60% [95% confidence interval (CI) 53-67] and specificity was 92% (95%CI: 90-94). The positive and negative likelihood ratios were 8.0 (95%CI: 5.8-11.0) and 0.43 (95%CI: 0.36-0.52), respectively. Diagnostic odds ratio was 19 (95%CI: 11-30) and area under the curve was 0.88 (95%CI: 0.85-0.91). The sensitivity and specificity for CRC screening were 64% (95%CI: 59-69) and 92% (95%CI: 91-93), respectively. The sensitivity and specificity for recurrence detection during follow-up were 54% (95%CI: 42-67) and 93% (95%CI: 88-96), respectively.

CONCLUSION

The detection of methylated BCAT1/IKZF1 in plasma, as a non-invasive detection method of circulating tumor DNA, has potential CRC diagnosis, but the clinical application prospect needs to be further explored.

Comprehensive Cost Implications of Commercially Available Noninvasive Colorectal Cancer Screening Modalities

BACKGROUND

There is an increasing usage of noninvasive screening modalities for colorectal cancer (CRC), primarily the fecal immunochemical test (FIT) and multi-target stool DNA test (Cologuard [CG]). The aim of this study was to determine the comprehensive, long-term cost implications of these noninvasive screening modalities.

STUDY DESIGN

Using a national insurer-based administrative dataset, patients screened for CRC from January 1, 2019 to December 31, 2019 were analyzed. A hierarchical logic system was used to determine the primary screening modality for each patient. The total annual costs in US dollars ($) were extrapolated using number of patients screened, costs per test, screening intervals, and costs incurred from false results. Patients within our tumor registry diagnosed with CRC were matched to their claims data, and cancer stage distribution was compared.

RESULTS

Of 119,334 members who underwent noninvasive screening, 38.1% underwent screening with FIT and 40.0% with CG. The combined annual cost for these 2 screening modalities was $13.7 million. By transitioning to FIT alone for all noninvasive screening, the total annual cost would decrease to $7.9 million, resulting in a savings of approximately $5.8 million per year. Additionally, by combining data from the network cancer registry and insurer-based claims dataset, we were able to match 533 individuals who underwent screening and were later diagnosed with CRC. The rate of early-stage (stage 0 to II) disease was found to be similar between those screened with FIT and CG (59.5% FIT vs 63.2% CG; p = 0.77).

CONCLUSIONS

The adoption of FIT as the primary noninvasive CRC screening method has the potential to generate significant cost savings, and therefore, carries significant value implications for a large population health system.

Colorectal cancer screening: The role of MT-sDNA testing

ABSTRACT

Because an estimated 10.5% of new colorectal cancer (CRC) cases occur in patients under age 50 years, the US Preventive Services Task Force in 2021 recommended CRC screening for adults ages 45 to 49 years. The prevalence of up-to-date CRC screening with any recommended test among patients age 45 years and older in the United States is only 59% in 2023, indicating that existing screening practices are ineffective. Screening options now include invasive and noninvasive measures. Multi-target stool DNA (MT-sDNA) testing is a simple, low-risk, noninvasive test that provides excellent sensitivity and specificity, is cost-effective, and may increase patient screening rates. CRC screening guideline recommendations and alternative screening methods may help improve patient outcomes and reduce morbidity and mortality. This article describes MT-sDNA testing, its effectiveness, recommended use, and potential expanding role as a screening option.

Joint Asian Pacific Association of Gastroenterology (APAGE)-Asian Pacific Society of Digestive Endoscopy (APSDE) clinical practice guidelines on the use of non-invasive biomarkers for diagnosis of colorectal neoplasia

Screening for colorectal cancer (CRC) is effective in reducing CRC related mortality. Current screening methods include endoscopy based and biomarker based approaches. This guideline is a joint official statement of the Asian Pacific Association of Gastroenterology (APAGE) and the Asian Pacific Society of Digestive Endoscopy (APSDE), developed in response to the increasing use of, and accumulating supportive evidence for the role of, non-invasive biomarkers for the diagnosis of CRC and its precursor lesions. A systematic review of 678 publications and a two stage Delphi consensus process involving 16 clinicians in various disciplines was undertaken to develop 32 evidence based and expert opinion based recommendations for the use of faecal immunochemical tests, faecal based tumour biomarkers or microbial biomarkers, and blood based tumour biomarkers for the detection of CRC and adenoma. Comprehensive up-to-date guidance is provided on indications, patient selection and strengths and limitations of each screening tool. Future research to inform clinical applications are discussed alongside objective measurement of research priorities. This joint APAGE-APSDE practice guideline is intended to provide an up-to-date guide to assist clinicians worldwide in utilising non-invasive biomarkers for CRC screening; it has particular salience for clinicians in the Asia-Pacific region.

Colon Cancer Screening Methods: 2023 Update

Colorectal cancer (CRC) is a significant cause of morbidity and mortality worldwide. National screening guidelines have been implemented to identify and remove precancerous polyps before they become cancer. Routine CRC screening is advised for people with average risk starting at age 45 because it is a common and preventable malignancy. Various screening modalities are currently in use, ranging from stool-based tests (fecal occult blood test (FOBT), fecal immunochemical test (FIT), and FIT-DNA test), radiologic tests (computed tomographic colonography (CTC), double contrast barium enema), and visual endoscopic examinations (flexible sigmoidoscopy (FS), colonoscopy, and colon capsule endoscopy (CCE)) with their varying sensitivity and specificity. Biomarkers also play a vital role in assessing the recurrence of CRC. This review offers a summary of the current screening options, including biomarkers available to detect CRC, highlighting the benefits and challenges encompassing each screening modality.

Effectiveness of Colorectal Cancer (CRC) Screening on All-Cause and CRC-Specific Mortality Reduction: A Systematic Review and Meta-Analysis

(1) Background: The aim of this study was to pool and compare all-cause and colorectal cancer (CRC) specific mortality reduction of CRC screening in randomized control trials (RCTs) and simulation models, and to determine factors that influence screening effectiveness. (2) Methods: PubMed, Embase, Web of Science and Cochrane library were searched for eligible studies. Multi-use simulation models or RCTs that compared the mortality of CRC screening with no screening in general population were included. CRC-specific and all-cause mortality rate ratios and 95% confidence intervals were calculated by a bivariate random model. (3) Results: 10 RCTs and 47 model studies were retrieved. The pooled CRC-specific mortality rate ratios in RCTs were 0.88 (0.80, 0.96) and 0.76 (0.68, 0.84) for guaiac-based fecal occult blood tests (gFOBT) and single flexible sigmoidoscopy (FS) screening, respectively. For the model studies, the rate ratios were 0.45 (0.39, 0.51) for biennial fecal immunochemical tests (FIT), 0.31 (0.28, 0.34) for biennial gFOBT, 0.61 (0.53, 0.72) for single FS, 0.27 (0.21, 0.35) for 10-yearly colonoscopy, and 0.35 (0.29, 0.42) for 5-yearly FS. The CRC-specific mortality reduction of gFOBT increased with higher adherence in both studies (RCT: 0.78 (0.68, 0.89) vs. 0.92 (0.87, 0.98), model: 0.30 (0.28, 0.33) vs. 0.92 (0.51, 1.63)). Model studies showed a 0.62-1.1% all-cause mortality reduction with single FS screening. (4) Conclusions: Based on RCTs and model studies, biennial FIT/gFOBT, single and 5-yearly FS, and 10-yearly colonoscopy screening significantly reduces CRC-specific mortality. The model estimates are much higher than in RCTs, because the simulated biennial gFOBT assumes higher adherence. The effectiveness of screening increases at younger screening initiation ages and higher adherences.

Passive monitoring by smart toilets for precision health

Smart toilets are a key tool for enabling precision health monitoring in the home, but such passive monitoring has ethical considerations.

Cost-Effectiveness of Earlier or More Intensive Colorectal Cancer Screening in Overweight and Obese Patients

BACKGROUND & AIMS

Overweight and obese persons have not only elevated rates of colorectal cancer (CRC), but also higher competing mortality and healthcare spending. We examined the cost-effectiveness of intensified CRC screening in overweight and obese persons.

METHODS

We adapted our validated decision analytic model of CRC screening to compare screening starting at 45 or 40 years of age instead of at 50 years of age, or shortening screening intervals, in women and men with body mass index (BMI) ranging from normal to grade III obesity. Strategies included colonoscopy every 10 years (Colo10) or every 5 years (Colo5), or annual fecal immunochemical test.

RESULTS

Without screening, sex-specific total CRC deaths were similar for persons with overweight or obesity I-III, reflecting the counterbalancing of higher CRC risk by lower life expectancy as BMI rises. For all BMI and sex groups, Colo10 starting at 45 years of age or FIT starting at 40 years of age were cost-effective at a threshold of $100,000 per quality-adjusted life year gained. Colo10 starting at 40 years of age was cost-effective only for men with obesity II-III, at $93,300 and $80,400 per quality-adjusted life year gained, respectively. Shifting Colo10 to earlier starting ages was always preferred over Colo5 starting at later ages. Results were robust in sensitivity analysis, including varying all-cause mortality, complication, and BMI-specific CRC risks.

CONCLUSIONS

CRC screening starting at 45 years of age with colonoscopy, or at 40 years of age with FIT, appears cost-effective for women and men across the range of BMI. In men with obesity II-III, who have the highest CRC but also all-cause mortality risks, colonoscopy starting at 40 years of age appears cost-effective. It remains to be decided whether BMI should be used as a single predictor or incorporated into a multivariable tool to tailor CRC screening.

The Use of a Non-Invasive Biomarker for Colorectal Cancer Screening: A Comparative Cost-Effectiveness Modeling Study

This study aimed to examine the cost-effectiveness of fecal biomarker M3 panel compared to fecal immunochemical test (FIT) and colonoscopy in an Asian population. In a hypothetical population of 100,000 persons aged 50 years who received FIT yearly, M3 biomarker yearly, or colonoscopy every 10 years until the age of 75 years. Participants with positive FOBT or a result of "high risk" identified using the M3 biomarker are offered colonoscopy. We assumed surveillance colonoscopy is repeated every 3 years, and examined the treatment cost. A comparison of various outcome measures was conducted using Markov modelling. The incremental cost-effectiveness ratio (ICER) of FIT, M3 biomarker, and colonoscopy was USD108,176, USD133,485 and USD159,596, respectively. Comparing with FIT, the use of M3 biomarker could lead to significantly smaller total loss of cancer-related life-years (2783 vs. 5279); a higher number of CRC cases prevented (1622 vs. 146), a higher proportion of CRC cases prevented (50.2% vs. 4.5%), more life-years saved (2852 vs. 339), and cheaper total costs per life-year saved (USD212,553 vs. 773,894). The total costs per life-year saved is more affordable than that achieved by colonoscopy as a primary screening tool (USD212,553 vs. USD236,909). The findings show that M3 biomarkers may be more cost-effective than colonoscopy.

A Comparison of Single and Combined Schemes of Asia-Pacific Colorectal Screening, Faecal Immunochemical and Stool Deoxyribonucleic Acid Testing for Community Colorectal Cancer Screening

Objective

To compare the screening efficacy of colonoscopy and pathologically confirmed single and combined Asia-Pacific colorectal screening (APCS), faecal immunochemical testing (FIT) and stool deoxyribonucleic acid (sDNA) testing protocols.

Methods

From April 2021 to April 2022, 842 volunteers participated in primary colorectal cancer (CRC) screenings using APCS scoring, FIT and sDNA testing and 115 underwent a colonoscopy. One hundred high-risk participants were then identified from the results of both processes. The differences in the three CRC screening tests in combination with the colonoscopy pathology diagnostics were evaluated using Cochran's Q test, the Dunn-Bonferroni test and area under the receiver operating characteristic curve (AUC) value analysis.

Results

Both FIT and sDNA testing demonstrated a 100% performance in detecting CRC. For advanced adenoma, the sensitivity of the FIT + sDNA test scheme (double positive) was 29.2%, and the sensitivities of the combined FIT + sDNA test and APCS scoring + sDNA test schemes were 62.5% and 95.8%, respectively. The FIT + sDNA testing kappa value of advanced colorectal neoplasia was 0.344 (p = 0.011). The sensitivity for nonadvanced adenoma of the APCS score + sDNA test scheme was 91.1%. In terms of positive results, the sensitivity of the APCS score + FIT + sDNA detection protocol was significantly higher than that of the APCS score, FIT, sDNA detection, and FIT + sDNA detection methods (adjusted p < 0.001, respectively). For the FIT + sDNA test, the kappa value was 0.220 (p = 0.015) and the AUC was 0.634 (p = 0.037). The specificity of the FIT + sDNA test scheme was 69.0%.

Conclusion

The FIT + sDNA test scheme demonstrated superior diagnostic efficacy, and the combined APCS score + FIT + sDNA test scheme demonstrated remarkable improvements in CRC screening efficiency and sensitivity for detecting positive lesions.

Cost-Effectiveness of Colorectal Cancer Surveillance in Hodgkin Lymphoma Survivors Treated with Procarbazine and/or Infradiaphragmatic Radiotherapy

BACKGROUND

Hodgkin lymphoma survivors treated with infradiaphragmatic radiotherapy (IRT) and/or procarbazine have an increased risk of developing colorectal cancer. We investigated the cost-effectiveness of colorectal cancer surveillance in Dutch Hodgkin lymphoma survivors to determine the optimal surveillance strategy for different Hodgkin lymphoma subgroups.

METHODS

The Microsimulation Screening Analysis-Colon model was adjusted to reflect colorectal cancer and other-cause mortality risk in Hodgkin lymphoma survivors. Ninety colorectal cancer surveillance strategies were evaluated varying in starting and stopping age, interval, and modality [colonoscopy, fecal immunochemical test (FIT, OC-Sensor; cutoffs: 10/20/47 μg Hb/g feces), and multi-target stool DNA test (Cologuard)]. Analyses were also stratified per primary treatment (IRT and procarbazine or procarbazine without IRT). Colorectal cancer deaths averted (compared with no surveillance) and incremental cost-effectiveness ratios (ICER) were primary outcomes. The optimal surveillance strategy was identified assuming a willingness-to-pay threshold of €20,000 per life-years gained (LYG).

RESULTS

Overall, the optimal surveillance strategy was annual FIT (47 μg) from age 45 to 70 years, which might avert 70% of colorectal cancer deaths in Hodgkin lymphoma survivors (compared with no surveillance; ICER:€18,000/LYG). The optimal surveillance strategy in Hodgkin lymphoma survivors treated with procarbazine without IRT was biennial FIT (47 μg) from age 45 to 70 years (colorectal cancer mortality averted 56%; ICER:€15,000/LYG), and when treated with IRT and procarbazine, annual FIT (47 μg) surveillance from age 40 to 70 was most cost-effective (colorectal cancer mortality averted 75%; ICER:€13,000/LYG).

CONCLUSIONS

Colorectal cancer surveillance in Hodgkin lymphoma survivors is cost-effective and should commence earlier than screening occurs in population screening programs. For all subgroups, FIT surveillance was the most cost-effective strategy.

IMPACT

Colorectal cancer surveillance should be implemented in Hodgkin lymphoma survivors.

Analysis of blood markers for early colorectal cancer diagnosis

BACKGROUND

Colorectal cancer (CRC) is a very common tumor worldwide. Its mortality can be limited by early diagnosis through screening programs. These programs are based on fecal occult blood testing and colonoscopy. Our objective was to find a model based on the determination of blood biomarkers that was efficacious enough to become part of the early diagnosis of CRC.

METHODS

In a total of 221 patients who underwent a colonoscopy, two types of markers were identified (I) classic: carcinoembryonic antigen (CEA), CA19.9, α-fetoprotein, CA125, CA72.4, and ferritin; and (II) experimental: neutrophil gelatinase-associated lipocalin (NGAL), estimated glomerular filtration rate (EGFR), 8-hydroxydeoxyguanosine (8OHdG), calprotectin, and cysteine-rich 61 (Cyr61). We divided the patients into four groups according to colonoscopy results: a control group (n=83) with normal colonoscopy, a polyp group (n=56), a CRC group (n=45), and an inflammatory disease group (n=37). We built an algorithm based on multivariate logistic regression analysis.

RESULTS

A total of 51.6% were males, and the median age was 63 years. We designed an algorithm based on the combination of several markers that discriminated CRC patients from the rest of the patients with a performance of 94%, a sensitivity of 95.6%, and a specificity of 80.6%. Discriminating by sex also resulted in two powerful algorithms, although it performed better in males (97% vs. 91%).

CONCLUSIONS

Our study has devised a predictive model with high efficacy based on the determination of several biomarkers. We think that it could be incorporated into the set of methods used in CRC screening.

Epidemiology, risk factors, and prevention of colorectal cancer

Background: Colorectal cancer remains the fourth most common malignancy in Korea, and has been ranked as the third leading cause of cancer deaths in 2020. This study aims to describe the epidemiologic status of colorectal cancer in Korea, and provide basic data for effective primary and secondary prevention methods by summarizing risk factors and screening tools.Current Concepts: Although colorectal cancer incidence and mortality have decreased in recent years in Korea, it still poses a significant public health burden. From the early 1990s until the mid-2000s, the 5-year relative survival of patients with colorectal cancer in Korea continuously increased. This can be attributed to the successful introduction of the government-led screening program; development of improved surgical techniques, anticancer drugs, and adjuvant treatment; and advances medical resources and infrastructure along with economic growth. However, since the late 2000s, the improvement in survival has stagnated. The coronavirus disease 2019 outbreak has reduced hospital visits and screenings, which is assumed to cause delays in diagnosis, leading to a worse prognosis in the patients. To overcome these obstacles, it is essential to explore modifiable environmental risk factors and appropriate screening test methods in Korea.Discussion and Conclusion: Primary prevention through risk factor modification and secondary prevention using suitable screening programs can reduce the incidence and mortality rates of colorectal cancer.

Cost-effectiveness of colorectal cancer screening strategies: A systematic review

INTRODUCTION

Colorectal cancer (CRC) is the second leading cause of death worldwide and the use of CRC screening tests can reduce the incidence and mortality of the disease by early detection. This study aims to review cost-effectiveness strategies in different ages and countries, systematically.

METHODS

We searched ProQuest, Web of Science, Scopus, Cochrane, PubMed and Embase for related studies between 2010 and 2020. Articles that reported costs per Quality-Adjusted Life Year or Life Year Gain and Incremental Cost-Effectiveness Ratios to compare the cost-effectiveness of CRC screening strategies in the average-risk population were included in our study.

RESULTS

The search strategies identified 426 records and finally 48 articles were included in the systematic review based on included and excluded criteria. We identified seven strategies for CRC screening. Most of the strategies were performed in aged 50-75. These studies were reported by cost per Quality-Adjusted life year (QALY)/Life Year Gain (LYG) based on methods and perspectives and the ICER of comparison of two-by-two strategies.

CONCLUSION

Most of the CRC screening strategies were cost-effective, but there was big heterogeneity between the cost-effectiveness analysis of CRC screening strategies because of different screening methods, perspectives and screening populations. So, it is important to consider this heterogeneity to compare the economic evaluation studies in this field.

Feasibility of quantification based on novel evaluation with stool DNA and fecal immunochemical test for colorectal cancer detection

Background

Stool DNA (sDNA) tests and fecal immunochemical test (FIT) are used for the detection of colorectal cancer (CRC). Here we performed a novel evaluation using sDNA and FIT to assess their performance in CRC screening and monitoring in Hubei, China.

Methods

Stool samples were collected from a high-risk population in Hubei, China (n = 359). sDNA tests and FIT were performed to test for KRAS mutations, NDRG4 and BMP3 methylation, and check hemoglobin levels. The methylation in BMP3 and NDRG4 genes was detected by TaqMan PCR method from human fecal samples. KRAS gene mutation in human fecal DNA was tested using TaqMan probe and amplification-refractory mutation system method. The colloid gold method was used for detection of hemoglobin in fecal samples. Finally, a novel evaluation by software was used to calculate the comprehensive value of the combined results for CRC detection and monitoring.

Results

The sensitivity and specificity of the novel evaluation for early CRC (stage I and II), advanced adenoma (AA), and non-colon cancer neoplasm (NA) detection were 95.45% and 81.6%, 29.63% and 75.9%, and 23.08% and 75.17%, respectively. The receiver operating characteristic (ROC) curves of the combined value for the above diseases were 0.945 ± 0.015, 0.543 ± 0.055, and 0.547 ± 0.038, respectively. The levels of the novel evaluation were not significantly associated with the pathology and stage (P > 0.05). In 20 out of 22 CRC patients, the novel evaluation of sDNA and FIT had decreased below threshold (< 165) at after surgery.

Discussion

The novel evaluation with sDNA test and FIT has increased sensitivity for screening of CRC and AA. The novel evaluation may have potential importance as an indicator of early CRC. Additionally, the dynamic changes of the comprehensive value after surgery were correlated with CRC treatment.

Evaluating the quality of the economic evidence in colorectal cancer genomics studies

The increase in the use of genome-based screening and diagnostic tests adds to the overall costs of oncologic care for colorectal cancer. This, in turn, has resulted in an increase in published economic analyses. Aim: To perform a systematic literature review of the available economic evidence evaluating the value of genomic testing for colorectal cancer and appraise the quality of the economic studies conducted to date. Methods: A systematic review of the literature for economic studies of colorectal cancer genomics from January 2006 through October 2020, and evaluation of study quality using the Quality of Health Economic Studies (QHES) instrument was conducted. The validated QHES was then applied to a final set of articles that met eligibility criteria. Results: Our search of the literature initially yielded 12,859 records. A final set of 49 articles met our inclusion criteria. The QHES score ranged from 24 to 100, with an average score of 82. Most of the studies (n = 40, 82%) scored above 75 and were considered of good quality. Conclusion: Our analysis revealed that most of the economic analyses of colorectal cancer genomic molecular diagnostics in the literature may be of good quality. There is, however, some variation in methodological rigor between the articles.

Bottom-Up Approach to the Discovery of Clinically Relevant Biomarker Genes: The Case of Colorectal Cancer

Traditional approaches to genome-wide marker discovery often follow a common top-down strategy, where a large scale ‘omics’ investigation is followed by the analysis of functional pathways involved, to narrow down the list of identified putative biomarkers, and to deconvolute gene expression networks, or to obtain an insight into genetic alterations observed in cancer. We set out to investigate whether a reverse approach would allow full or partial reconstruction of the transcriptional programs and biological pathways specific to a given cancer and whether the full or substantially expanded list of putative markers could thus be identified by starting with the partial knowledge of a few disease-specific markers. To this end, we used 10 well-documented differentially expressed markers of colorectal cancer (CRC), analyzed their transcription factor networks and biological pathways, and predicted the existence of 193 new putative markers. Incredibly, the use of a validation marker set of 10 other completely different known CRC markers and the same procedure resulted in a very similar set of 143 predicted markers. Of these, 138 were identical to those found using the training set, confirming our main hypothesis that a much-expanded set of disease markers can be predicted by starting with just a small subset of validated markers. Further to this, we validated the expression of 42 out of 138 top-ranked predicted markers experimentally using qPCR in surgically removed CRC tissues. We showed that 41 out of 42 mRNAs tested have significantly altered levels of mRNA expression in surgically excised CRC tissues. Of the markers tested, 36 have been reported to be associated with aspects of CRC in the past, whilst only limited published evidence exists for another three genes (BCL2, PDGFRB and TSC2), and no published evidence directly linking genes to CRC was found for CCNA1, SHC1 and TGFB3. Whilst we used CRC to test and validate our marker discovery strategy, the reported procedures apply more generally to cancer marker discovery.

Advances in tests for colorectal cancer screening and diagnosis

INTRODUCTION

Colorectal cancer (CRC) is the second leading cause of cancer-related deaths globally. Nonetheless, with early detection of CRC or its precancerous lesions, mortality, and CRC incidence can be reduced. Although colonoscopy is currently the gold standard for CRC screening and diagnosis, its invasive nature, and troublesome bowel preparation deter patient participation. Therefore, there is a need to expand the use of noninvasive or minimally invasive methods to increase patient compliance.

AREAS COVERED

This review summarizes advances in different methods for CRC screening, including stool bacterial and metagenomic markers, fecal proteins, genetic and epigenetic markers in blood and stools, and imaging modalities. The cost-effectiveness of these methods is also discussed. FIT is more cost-effective compared to virtual colonoscopy, mSEPT9 test, and Multitarget Stool DNA test, while the cost-effectiveness of other noninvasive methods requires further evaluation.

EXPERT OPINION

Recent evidence has well demonstrated the usefulness of gut microbiome and certain fecal bacterial markers in the noninvasive diagnosis of CRC and its precancerous lesions. Many of the fecal biomarkers, from host cells or the gut environment, show better diagnostic sensitivity than FIT. New screening tests based on these fecal biomarkers can be expected to replace FIT with higher cost-effectiveness in the near future.

Colorectal Cancer Diagnosis: The Obstacles We Face in Determining a Non-Invasive Test and Current Advances in Biomarker Detection

Simple Summary

Colorectal cancer (CRC) is one of the most common cancers in the western world. CRC originates from precursor adenomatous polyps, which may over time develop into cancer. Endoscopic evaluation remains the gold-standard investigation for the disease. In the absence of molecular tools for early detection, the removal of neoplastic adenomas via polypectomy remains an important measure to prevent dysplastic adenomas from evolving into invasive carcinoma. Colonoscopy is an intrusive procedure that provides an uncomfortable experience for patients. Kits for testing for the presence of blood hemoglobin in the stool are now widely used, and DNA methylation-based detection kits have been approved in the USA for testing the stool and plasma, but few other molecular biomarkers have found their way into medical practice. This review summarizes current trends in the detection and screening of CRC and provides a definitive review of emerging molecular biomarkers for CRC.

Abstract

Globally, colorectal cancer (CRC) is the third most common cancer, with 1.4 million new cases and over 700,000 deaths per annum. Despite being one of the most common cancers, few molecular approaches to detect CRC exist. Carcinoembryonic antigen (CEA) is a known serum biomarker that is used in CRC for monitoring disease recurrence or response to treatment. However, it can also be raised in multiple benign conditions, thus having no value in early detection or screening for CRC. Molecular biomarkers play an ever-increasing role in the diagnosis, prognosis, and outcome prediction of disease, however, only a limited number of biomarkers are available and none are suitable for early detection and screening of CRC. A PCR-based Epi proColon^® blood plasma test for the detection of methylated SEPT9 has been approved by the USFDA for CRC screening in the USA, alongside a stool test for methylated DNA from CRC cells. However, these are reserved for patients who decline traditional screening methods. There remains an urgent need for the development of non-invasive molecular biomarkers that are highly specific and sensitive to CRC and that can be used routinely for early detection and screening. A molecular approach to the discovery of CRC biomarkers focuses on the analysis of the transcriptome of cancer cells to identify differentially expressed genes and proteins. A systematic search of the literature yielded over 100 differentially expressed CRC molecular markers, of which the vast majority are overexpressed in CRC. In terms of function, they largely belong to biological pathways involved in cell division, regulation of gene expression, or cell proliferation, to name a few. This review evaluates the current methods used for CRC screening, current availability of biomarkers, and new advances within the field of biomarker detection for screening and early diagnosis of CRC.

Cross-cultural validation of stool Based Colorectal cancer screening methods in the North West of Iran

Background

Globally, colorectal cancer (CRC) is the third most common cancer and the second leading cause of death from cancer. Incidence and mortality from CRCboth can be reduced and prevented using screening and early detection programs. The current study aimed to assess the feasibility of the colorectal cancer screening program in Northwest of Iran.

Methods

The study designed as a cross-cultural analytic study, to evaluate the diagnostic accuracy of stool-based tests compared with colonoscopy, during 2016–2020. All individuals first were assessed with our CRC risk assessment tool, then eligible volunteers entered the study. Colonoscopy was performed on all participants, also stool-based tests including traditional guaiac, high-sensitivity guaiac-based, fecal immunochemical test (FIT), and multitarget stool DNA (Mt-sDNA) panel tests were performed.

Results

Mt-sDNA test panel had a sensitivity of 77.8% (95% CI: 40–97.2)for detecting colorectal cancer with a specificity of 91.2% (95% CI:85.4–95.2). The FIT test alone had a lower sensitivity (66.7%; 95% CI:29.9–92.5) and almost the same specificity of 93.9% (95% CI: 88.7–97.2) for cancer detection. Mt-sDNA test had better diagnostic accuracy than the FIT (AUC = 0.85 vs 0.80), and is a more useful screening test. Positive and negative predictive values for cancer detection for both Mt-sDNA and FIT tests were almost the same results, however Mt-sDNA test had better NPV results than the FIT test alone.

Conclusion

Our results showed that both Mt-sDNA panel and the FIT test had acceptable cut-off points for cancer detection, however, Mt-sDNA test had better diagnostic accuracy.

•

A priority of Iranian health policy must be to develop an executive plan to identify the appropriate CRC screening method.

•

This study provides a first step toward the design of a population-based CRC screening program in East Azerbaijan, Iran.

•

The current study has been performed to evaluate the diagnostic accuracy of stool-based tests for CRC screening.

•

Our results showed that both Mt-sDNA panel and the FIT test had acceptable cut-off points for cancer detection.

•

Among four stool -based tests, Mt-sDNA test had the highest sensitivity for detection of cancer and advanced adenoma.

Counting Advanced Precancerous Lesions as True Positives When Determining Colorectal Cancer Screening Test Specificity

The landmark Centers for Medicare & Medicaid Services (CMS) decision memo on blood-based biomarkers to screen for colorectal cancer (CRC) sets thresholds of 74% or higher for sensitivity and 90% or higher for specificity for CRC. This approach does not consider detection of advanced precancerous lesions as true positives. We contrasted the impact of counting advanced precancerous lesions as true vs false positives and projected CRC outcomes under contrasting tests in a validated model. A test with the threshold performance set by CMS decreased CRC incidence by 30% and CRC mortality by 48% in individuals aged 45 years. If this test also detected advanced precancerous lesions with 30% sensitivity, CRC incidence decreased by 45% and mortality by 58%, but the CRC specificity of the test of only 88% would not satisfy the CMS threshold. CMS should reconsider its definition of threshold specificity for CRC screening biomarkers. Future coverage determinations on biomarkers to screen for cancer should consider detection of relevant precursor lesions and projected outcomes.

Diagnostic Accuracy of Multitarget Stool DNA Testing for Colorectal Cancer Screening: A Systematic Review and Meta-analysis

This study aimed to collect and summarize test data and conduct a meta-analysis, with respect to the Multitarget Stool DNA test sensitivity and specificity, compared to colonoscopy. All manuscripts were screened for eligibility according to inclusion criteria. Participants were a normal population at an average risk of developing CRC. Intervention was Stool based and DNA panel tests compared with colonoscopy, and outcome was detection of CRC and any pre-cancerous lesions. Inter-study and inconsistency (using the I-squared test) were assessed. Meta-analyses of the Mt-sDNA test showed a combined sensitivity of 89%, 51%, and 76% for the detection of CRC, advanced adenoma (AA), and combined CRC and AA, respectively. The overall specificity was 91%, 89%, and 90% for the detection of CRC, AA, and combined CRC and AA, respectively. Mt-sDNA had significantly acceptable diagnostic accuracy for CRC and AA diagnosis, but still has lower sensitivity and specificity than colonoscopy.

Current and future colorectal cancer screening strategies

Despite strong evidence of effectiveness, colorectal cancer (CRC) screening remains underused. Currently, there are several options for CRC screening, each with its own performance characteristics and considerations for practice. This Review aims to cover current CRC screening guidelines and highlight future blood-based and imaging-based options for screening. In current practice, the leading non-invasive option is the faecal immunochemical test (FIT) based on its high specificity, good sensitivity, low cost and ease of use in mailed outreach programmes. There are currently five blood-based CRC screening tests in varying stages of evaluation, including one that is currently sold in the USA as a laboratory-developed test. There are ongoing studies on the diagnostic accuracy and longitudinal performance of blood tests and they have the potential to disrupt the CRC screening landscape. Imaging-based options, including the colon capsule, MR colonography and the CT capsule, are also being tested in active studies. As the world attempts to recover from the COVID-19 pandemic and adapts to the start of CRC screening among people at average risk starting at age 45 years, non-invasive options will become increasingly important.

Screening for Colorectal Cancer Leading into a New Decade: The "Roaring '20s" for Epigenetic Biomarkers?

Colorectal cancer (CRC) has an important bearing (top five) on cancer incidence and mortality in the world. The etiology of sporadic CRC is related to the accumulation of genetic and epigenetic alterations that result in the appearance of cancer hallmarks such as abnormal proliferation, evasion of immune destruction, resistance to apoptosis, replicative immortality, and others, contributing to cancer promotion, invasion, and metastasis. It is estimated that, each year, at least four million people are diagnosed with CRC in the world. Depending on CRC staging at diagnosis, many of these patients die, as CRC is in the top four causes of cancer death in the world. New and improved screening tests for CRC are needed to detect the disease at an early stage and adopt patient management strategies to decrease the death toll. The three pillars of CRC screening are endoscopy, radiological imaging, and molecular assays. Endoscopic procedures comprise traditional colonoscopy, and more recently, capsule-based endoscopy. The main imaging modality remains Computed Tomography (CT) of the colon. Molecular approaches continue to grow in the diversity of biomarkers and the sophistication of the technologies deployed to detect them. What started with simple fecal occult blood tests has expanded to an armamentarium, including mutation detection and identification of aberrant epigenetic signatures known to be oncogenic. Biomarker-based screening methods have critical advantages and are likely to eclipse the classical modalities of imaging and endoscopy in the future. For example, imaging methods are costly and require highly specialized medical personnel. In the case of endoscopy, their invasiveness limits compliance from large swaths of the population, especially those with average CRC risk. Beyond mere discomfort and fear, there are legitimate iatrogenic concerns associated with endoscopy. The risks of perforation and infection make endoscopy best suited for a confirmatory role in cases where there are positive results from other diagnostic tests. Biomarker-based screening methods are largely non-invasive and are growing in scope. Epigenetic biomarkers, in particular, can be detected in feces and blood, are less invasive to the average-risk patient, detect early-stage CRC, and have a demonstrably superior patient follow-up. Given the heterogeneity of CRC as it evolves, optimal screening may require a battery of blood and stool tests, where each can leverage different pathways perturbed during carcinogenesis. What follows is a comprehensive, systematic review of the literature pertaining to the screening and diagnostic protocols used in CRC. Relevant articles were retrieved from the PubMed database using keywords including: "Screening", "Diagnosis", and "Biomarkers for CRC". American and European clinical trials in progress were included as well.

Disparities in Colorectal Cancer Screening Practices in a Midwest Urban Safety-Net Healthcare System

AIMS

Although colorectal cancer screening (CRC) using stool-based test is well-studied, evidence on fecal immunochemical test (FIT) patterns in a safety-net healthcare system utilizing opportunistic screening is limited. We studied the FIT completion rates and adenoma detection rate (ADR) of positive FIT-colonoscopy (FIT-C) in an urban safety-net system.

METHODS

We performed a retrospective cross-sectional chart review on individuals ≥ 50 years who underwent CRC screening using FIT or screening colonoscopy, 09/01/2017-08/30/2018. Demographic differences in FIT completion were studied; ADR of FIT-C was compared to that of screening colonoscopy.

RESULTS

Among 13,427 individuals with FIT ordered, 7248 (54%) completed the stool test and 230 (48%) followed up a positive FIT with colonoscopy. Increasing age (OR 1.01, CI 1.01-1.02), non-Hispanic Blacks (OR 0.87, CI 0.80-0.95, p = 0.002), current smokers (OR 0.84, CI 0.77-0.92, p < 0.0001), those with Medicaid (OR 0.86, CI 0.77-0.96, p = 0.006), commercial insurance (OR 0.85, CI 0.78-0.94, p = 0.002), CCI score ≥ 3 (OR 0.82, CI 0.74-0.91, p < 0.0001), orders by family medicine providers (OR 0.87, CI 0.81-0.94, p < 0.0001) were associated with lower completion of stool test. Individuals from low median household income cities had lower follow-up of positive FIT, OR 0.43, CI 0.21-0.86, p = 0.017. ADR of FIT-C was higher than that of screening colonoscopy.

CONCLUSION

Adherence to CRC screening is low in safety-net systems employing opportunistic screening. Understanding demographic differences may allow providers to formulate targeted strategies in high-risk vulnerable groups.

Comparing the Cost-Effectiveness of Innovative Colorectal Cancer Screening Tests

Background

Colorectal cancer (CRC) screening with colonoscopy and the fecal immunochemical test (FIT) is underused. Innovative tests could increase screening acceptance. This study determined which of the available alternatives is most promising from a cost-effectiveness perspective.

Methods

The previously validated Microsimulation Screening Analysis-Colon model was used to evaluate the cost-effectiveness of screening with capsule endoscopy every 5 or 10 years, computed tomographic colonography every 5 years, the multi-target stool DNA test every 1 or 3 years, and the methylated SEPT9 DNA plasma assay (mSEPT9) every 1 or 2 years. We also compared these strategies with annual FIT screening and colonoscopy screening every 10 years. Quality-adjusted life-years gained (QALYG), number of colonoscopies, and incremental cost-effectiveness ratios were projected. We assumed a willingness-to-pay threshold of $100 000 per QALYG.

Results

Among the alternative tests, computed tomographic colonography every 5 years, annual mSEPT9, and annual multi-target stool DNA screening had incremental cost-effectiveness ratios of $1092, $63 253, and $214 974 per QALYG, respectively. Other screening strategies were more costly and less effective than (a combination of) these 3. Under the assumption of perfect adherence, annual mSEPT9 screening resulted in more QALYG, CRC cases averted, and CRC deaths averted than annual FIT screening but led to a high rate of colonoscopy referral (51% after 3 years, 69% after 5 years). The alternative tests were not cost-effective compared with FIT and colonoscopy.

Conclusions

This study suggests that for individuals not willing to participate in FIT or colonoscopy screening, mSEPT9 is the test of choice if the high colonoscopy referral rate is acceptable to them.

Detection of Postcolonoscopy Colorectal Neoplasia by Multi-target Stool DNA

INTRODUCTION

Significant variability between colonoscopy operators contributes to postcolonoscopy colorectal cancers (CRCs). We aimed to estimate postcolonoscopy colorectal neoplasia (CRN) detection by multi-target stool DNA (mt-sDNA), which has not previously been studied for this purpose.

METHODS

In a retrospective cohort of patients with +mt-sDNA and completed follow-up colonoscopy, positive predictive value (PPV) for endpoints of any CRN, advanced adenoma, right-sided neoplasia, sessile serrated polyps (SSP), and CRC were stratified by the time since previous colonoscopy (0-9, 10, and ≥11 years). mt-sDNA PPV at ≤9 years from previous average-risk screening colonoscopy was used to estimate CRN missed at previous screening colonoscopy.

RESULTS

Among the 850 studied patients with +mt-sDNA after a previous negative screening colonoscopy, any CRN was found in 535 (PPV 63%). Among 107 average-risk patients having +mt-sDNA ≤9 years after last negative colonoscopy, any CRN was found in 67 (PPV 63%), advanced neoplasia in 16 (PPV 15%), right-sided CRN in 48 (PPV 46%), and SSP in 20 (PPV 19%). These rates were similar to those in 47 additional average risk persons with previous incomplete colonoscopy and in an additional 68 persons at increased CRC risk. One CRC (stage I) was found in an average risk patient who was mt-sDNA positive 6 years after negative screening colonoscopy.

DISCUSSION

The high PPV of mt-sDNA 0-9 years after a negative screening colonoscopy suggests that lesions were likely missed on previous examination or may have arisen de novo. mt-sDNA as an interval test after negative screening colonoscopy warrants further study.

Cost-Effectiveness of Multitarget Stool DNA Testing vs Colonoscopy or Fecal Immunochemical Testing for Colorectal Cancer Screening in Alaska Native People

OBJECTIVE

To estimate the cost-effectiveness of multitarget stool DNA testing (MT-sDNA) compared with colonoscopy and fecal immunochemical testing (FIT) for Alaska Native adults.

PATIENTS AND METHODS

A Markov model was used to evaluate the 3 screening test effects over 40 years. Outcomes included colorectal cancer (CRC) incidence and mortality, costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios (ICERs). The study incorporated updated evidence on screening test performance and adherence and was conducted from December 15, 2016, through November 6, 2019.

RESULTS

With perfect adherence, CRC incidence was reduced by 52% (95% CI, 46% to 56%) using colonoscopy, 61% (95% CI, 57% to 64%) using annual FIT, and 66% (95% CI, 63% to 68%) using MT-sDNA. Compared with no screening, perfect adherence screening extends life by 0.15, 0.17, and 0.19 QALYs per person with colonoscopy, FIT, and MT-sDNA, respectively. Colonoscopy is the most expensive strategy: approximately $110 million more than MT-sDNA and $127 million more than FIT. With imperfect adherence (best case), MT-sDNA resulted in 0.12 QALYs per person vs 0.05 and 0.06 QALYs per person by FIT and colonoscopy, respectively. Probabilistic sensitivity analyses supported the base-case analysis. Under varied adherence scenarios, MT-sDNA either dominates or is cost-effective (ICERs, $1740-$75,868 per QALY saved) compared with FIT and colonoscopy.

CONCLUSION

Each strategy reduced costs and increased QALYs compared with no screening. Screening by MT-sDNA results in the largest QALY savings. In Markov model analysis, screening by MT-sDNA in the Alaska Native population was cost-effective compared with screening by colonoscopy and FIT for a wide range of adherence scenarios.

Cost-effectiveness analysis of alternative colorectal cancer screening strategies in high-risk individuals

BACKGROUND AND AIMS

Current guidelines recommend colonoscopy every 3-5 years for colorectal cancer (CRC) screening of individuals with a familial history of CRC. The objective of this study was to compare the cost effectiveness of screening alternatives in this population.

METHODS

Eight screening strategies were compared with no screening: fecal immunochemical test (FIT), Stool DNA and blood-based screening every 2 years, colonoscopy, computed tomography colonography, colon capsules, and sigmoidoscopy every 5 years, and colonoscopy at 45 years followed, if negative, by FIT every 2 years. Screening test and procedures performance were obtained from the literature. A microsimulation model reproducing the natural history of CRC was used to estimate the cost (€2018) and effectiveness [quality-adjusted life-years (QALYs)] of each strategy. A lifetime horizon was used. Costs and effectiveness were discounted at 3.5% annually.

RESULTS

Compared with no screening, colonoscopy and sigmoidoscopy at a 30% uptake were the most effective strategy (46.3 and 43.9 QALY/1000). FIT at a 30 µg/g threshold with 30% uptake was only half as effective (25.7 QALY). Colonoscopy was associated with a cost of €484,000 per 1000 individuals whereas sigmoidoscopy and FIT were associated with much lower costs (€123,610 and €66,860). Incremental cost-effectiveness rate for FIT and sigmoidoscopy were €2600/QALY (versus no screening) and €3100/QALY (versus FIT), respectively, whereas it was €150,000/QALY for colonoscopy (versus sigmoidoscopy). With a lower threshold (10 µg/g) and a higher uptake of 45%, FIT was more effective and less costly than colonoscopy at a 30% uptake and was associated with an incremental cost-effectiveness ratio (ICER) of €4240/QALY versus no screening.

CONCLUSION

At 30% uptake, current screening is the most effective screening strategy for high-risk individuals but is associated with a high ICER. Sigmoidoscopy and FIT at lower thresholds (10 µg/g) and a higher uptake should be given consideration as cost-effective alternatives.

PLAIN LANGUAGE SUMMARY

Cost-effectiveness analysis of colorectal cancer screening strategies in high-risk individuals Fecal occult blood testing with an immunochemical test (FIT) is generally considered as the most cost-effective alternative in colorectal cancer screening programs for average risk individuals without family history.Current screening guidelines for high-risk individuals with familial history recommend colonoscopy every 3-5 years.Colonoscopy every 3-5 years for individuals with familial history is the most effective strategy but is associated with a high incremental cost-effectiveness ratio.Compared with colonoscopy, if screening based on FIT is associated with a higher participation rate, it can achieve a similar effectiveness at a lower cost.

ACG Clinical Guidelines: Colorectal Cancer Screening 2021

Colorectal cancer (CRC) is the third most common cancer in men and women in the United States. CRC screening efforts are directed toward removal of adenomas and sessile serrated lesions and detection of early-stage CRC. The purpose of this article is to update the 2009 American College of Gastroenterology CRC screening guidelines. The guideline is framed around several key questions. We conducted a comprehensive literature search to include studies through October 2020. The inclusion criteria were studies of any design with men and women age 40 years and older. Detailed recommendations for CRC screening in average-risk individuals and those with a family history of CRC are discussed. We also provide recommendations on the role of aspirin for chemoprevention, quality indicators for colonoscopy, approaches to organized CRC screening and improving adherence to CRC screening. CRC screening must be optimized to allow effective and sustained reduction of CRC incidence and mortality. This can be accomplished by achieving high rates of adherence, quality monitoring and improvement, following evidence-based guidelines, and removing barriers through the spectrum of care from noninvasive screening tests to screening and diagnostic colonoscopy. The development of cost-effective, highly accurate, noninvasive modalities associated with improved overall adherence to the screening process is also a desirable goal.

Fecal Multidimensional Assay for Non-Invasive Detection of Colorectal Cancer: Fecal Immunochemical Test, Stool DNA Mutation, Methylation, and Intestinal Bacteria Analysis

Background

Fecal immunochemical test (FIT), DNA mutation, DNA methylation, and microbial dysbiosis all showed promising in colorectal cancer (CRC) non-invasive detection. We assessed CRC detection with an assay combining all these strategies and investigated the effect of clinical features on the performance of this comprehensive test.

Methods

We performed a multidimensional analysis study using stool samples collected from 108 patients with CRC, 18 patients with colorectal adenoma, and 36 individuals with no evidence of colorectal disease. The multidimensional analysis of stool samples including FIT, stool DNA (sDNA) tests for three methylated genes (Septin9, NDRG4, BMP3) and three mutated genes (KRAS, BRAF, PI3KCA) using next generation sequencing as well as detection of stool bacteria level of Fusobacterium nucleatum and Parvimonas micra using qPCR method. We used a linear support vector classification model to analyze the data.

Results

The sensitivity of FIT alone was 69.4% for CRC and 11.1% for adenoma. Separately, the sensitivity of the detection of intestinal bacteria, DNA mutation, and DNA methylation for CRC was 58.3, 50.0, and 51.9%, respectively. The combination of FIT and sDNA tests had a sensitivity of 81.5% for CRC (AUC: 0.93, better than FIT alone, P = 0.017) and 27.8% for adenoma with 94.4% specificity. Sensitivity of the multidimensional test to detect CRC with stage II (84.6%) and III (91.9%) CRC was relatively higher (88.2%) than that of patients with stage I (60.0%) and stage IV (75.0%) (P = 0.024). The rate of CRC detection increased with tumor size (P = 0.008) and age (P = 0.04). Interestingly, the rate of CRC detection was higher in smoking persons than non-smokers with marginal significance (P = 0.08).

Conclusions

The multidimensional assay of stool samples combining FIT and stool DNA tests further improved the diagnostic sensitivity for CRC. This could provide new approach for improvement of CRC screening and further demonstrations are warranted.

Stool DNA test targeting methylated syndecan-2 (SDC2) as a noninvasive screening method for colorectal cancer

Despite the steadily increasing worldwide incidence of colorectal cancer (CRC), an effective noninvasive approach for early detection of CRC is still under investigation. The guaiac-based fecal occult blood test (FOBT) and fecal immunochemical test (FIT) have gained popularity as noninvasive CRC screening tests owing to their convenience and relatively low costs. However, the FOBT and FIT have limited sensitivity and specificity. To develop a noninvasive tool for the detection of CRC, we investigated the sensitivity, specificity, and accuracy of a stool DNA test targeting methylated syndecan-2 (SDC2), which is frequently methylated in patients with CRC. The present study enrolled 62 patients diagnosed as having stage 0-IV CRC and 76 healthy participants between July 2018 and June 2019 from two institutions. Approximately 4.5 g of stool sample was collected from each participant for detection of human methylated SDC2 gene. In total, 48 of 62 (77.4%) patients with CRC showed positive results, whereas 67 out of 76 (88.2%) healthy participants showed negative results. The area under the curve of the receiver operating characteristic curve constructed was 0.872 for discrimination between patients with CRC and healthy individuals. The present study highlights the potential of the fecal methylated SDC2 test as a noninvasive detection method for CRC screening with a relatively favorable sensitivity of 77.4%, a specificity of 88.2% and a positive predictive value of 84.2% compared with other available fecal tests. Further multicenter clinical trials comprising subjects of varied ethnicities are required to validate this test for the mass screening of patients with CRC.

Specificity of the Multi-Target Stool DNA Test for Colorectal Cancer Screening in Average-Risk 45-49 Year-Olds: A Cross-Sectional Study

High-specificity colorectal cancer screening is desirable to triage patients <50 years for colonoscopy; however, most endorsed colorectal cancer screening tests have not been rigorously evaluated in younger populations. This prospective cross-sectional study determined the specificity of the multitarget stool DNA (mt-sDNA) test in an average-risk screening population of 45 to 49 year-olds. Specificity was the primary outcome and was measured in participants without colorectal cancer or advanced precancerous lesions [APL- advanced adenomas (AA), and sessile serrated lesions ≥10 mm], and in the subgroup of participants with negative colonoscopic findings. APL sensitivity was a secondary outcome. The evaluable cohort included those who completed the study without protocol deviations and had a usable mt-sDNA test. Of 983 enrolled participants, 816 formed the evaluable cohort, with a mean age of 47.8 (SD, 1.5) years; 47.7% were women. No participants had colorectal cancer, 49 had APL, 253 had nonadvanced adenomas (NAA), and 514 had negative colonoscopic findings. mt-sDNA test specificity was 95.2% (95% CI, 93.4-96.6) in participants with NAA or negative findings [96.3% (confidence interval (CI), 94.3%-97.8%)] in those with negative findings, and did not differ by sex (P = 0.75) or race (P = 0.36) in participants with NAA or negative findings. Sensitivity for APL was 32.7% (CI, 19.9-47.5%), with most APL (83.7%) measuring 10-19 mm and none having high-grade dysplasia. The area under the ROC curve for discriminating between APL and lesser findings was 0.72 (CI, 0.64-0.81). mt-sDNA's high specificity would help minimize risk from unnecessary diagnostic procedures in this age group. This study shows that mt-sDNA has high specificity among average-risk 45 to 49-year olds, supporting its use as a noninvasive option for colorectal cancer screening. PREVENTION RELEVANCE: This study shows that mt-sDNA has high specificity among average-risk 45-49 year olds, supporting its use as a non-invasive option for colorectal cancer screening.

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

BACKGROUND

Real-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.

METHODS

Predicted 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.

RESULTS

Each 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.

CONCLUSIONS

Adherence 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.