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

A Stool DNA-Based SDC2 Methylation Test for the Early Detection of Colorectal Cancer in an Asymptomatic, High-Risk Population: A Multicenter Prospective Randomized Trial

INTRODUCTION

Noninvasive stool DNA-based methylation testing has emerged as an effective strategy for the early colorectal cancer (CRC) detection. Syndecan-2 (SDC2) methylation frequently occurs in all stages of CRC; therefore, the aim of this study was to evaluate the clinical performance of a stool DNA-based SDC2 methylation test for detecting CRC in asymptomatic or high-risk CRC populations.

METHODS

This multicenter prospective study was conducted to determine the clinical performance of the SDC2 methylation test on stool DNA using real-time polymerase chain reaction. Stool samples were collected from asymptomatic individuals before colonoscopy, and the test results were independently analyzed through comparison with colonoscopic findings and pathological outcomes as reference standards.

RESULTS

Of the 1,124 evaluable participants, 20 had CRC, 73 had advanced adenomatous polyps (≥1.0 cm), 469 had nonadvanced adenomatous polyps (<1.0 cm), 178 had non-neoplastic polyps, and 384 had negative colonoscopy results. The stool SDC2 methylation test had a sensitivity and specificity of 95.0% and 81.5%, respectively, for detecting CRC, while the sensitivity for detecting advanced adenomatous polyps and CRC was 58.1%. The rate of adenoma detection increased with polyp size (P < 0.01), and sensitivity was not associated with CRC stage (P = 0.864).

DISCUSSION

The stool DNA-based SDC2 methylation test attained a high sensitivity for CRC detection in an asymptomatic high-risk population. Further large-scale clinical studies are required to validate the clinical utility of this test as a population-based CRC screening tool.

Analytical Validation of the Multitarget Stool RNA Test for Colorectal Cancer Screening

The multitarget stool RNA (mt-sRNA) test (ColoSense) is a noninvasive diagnostic test that screens for colorectal cancer and advanced adenomas in average-risk individuals aged 45 years and older. The mt-sRNA test incorporates a commercially available fecal immunochemical test, concentration of eight RNA transcripts, and participant-reported smoking status. As part of the CRC-PREVENT (Colorectal Cancer and Pre-Cancerous Adenoma Non-Invasive Detection Test) clinical trial, 12 analytical validation studies were conducted to assess analytical sensitivity, linearity, precision, interfering substances, cross-reactivity, carry-over, cross-contamination, and robustness. Analytical validation of the mt-sRNA test demonstrated limit of blank, limit of detection, and limit of quantification of <0.6, <0.7, and ≤2.5 copies/μL for all markers, respectively. The mt-sRNA test demonstrated linearity between 2.5 and 2500 copies/μL, and <20% coefficient of variation, and/or ≥95% concordance with regard to precision, interfering substances, carry-over, cross-contamination, and robustness. There was no significant impact of cross-reactivity from non-colorectal cancer diseases. These data provide a framework for laboratories to complete analytical validation for RNA-based panels that require premarket approval as a class III medical device from the US Food and Drug Administration.

Diagnostic Performance of Stool-based Testing for Colorectal Lesions Among Average-risk Individuals: A Real-world Evidence Study

OBJECTIVE

We assessed the real-world performance of stool-based tests (SBTs) for colorectal cancer screening.

MATERIALS AND METHODS

Retrospective review of average-risk individuals with positive SBT for advanced neoplasia (adenocarcinoma, advanced adenoma, and/or advanced serrated lesions) detection at follow-up colonoscopy.

RESULTS

There was no statistical difference in the detection of advanced neoplasia (P= 0.16) between SBTs [30.7% for multitargeted stool DNA (mt-sDNA) vs 22.8% for fecal immunochemical test]. However, there was a significant difference in the detection of advanced serrated lesions (11.3% for mt-sDNA vs 1.8% for fecal immunochemical test, P< 0.001).

CONCLUSION

There was no difference between SBTs for advanced neoplasia detection, though mt-sDNA detected significantly more advanced serrated lesions.

Adenomas and Sessile Serrated Lesions in 45- to 49-Year-Old Individuals Undergoing Colonoscopy: A Systematic Review and Meta-Analysis

INTRODUCTION

Colorectal cancer (CRC) screening is now recommended at the age of 45 years in the United States. However, information regarding the adenomas detection rate (ADR) and sessile serrated lesions (SSLs) in 45- to 49-year-old individuals is limited. In addition, the impact of lowering the screening age to 45 years on the ADR and the detection rate of SSLs is not well elucidated. This systematic review and meta-analysis aims to report the overall ADR and SSL detection rate in 45- to 49-year-old individuals undergoing colonoscopy.

METHODS

We searched MEDLINE, EMBASE, SCOPUS, Web of Science, ClinicalTrials.gov , and the Cochrane database from inception through October 2022 to identify studies reporting on ADR and SSL detection rates in 45- to 49-year-old individuals undergoing colonoscopies for all indications. This approach acknowledges the possibility of including individuals undergoing diagnostic colonoscopies or those with increased risk factors for CRC. We also conducted a separate analysis examining ADR in average-risk individuals undergoing screening colonoscopy. The pooled rates with their corresponding 95% confidence intervals (CIs) were generated using the fixed-effects model. I2 was used to adjudicate heterogeneity.

RESULTS

Sixteen studies met the inclusion criteria. All studies were retrospective except one; 3 had data from national/local registries. There were 41,709 adenomas detected across 150,436 colonoscopies. The pooled overall ADR was 23.1% (95% CI 19.7%-27.0%, I2 = 98.6%). The pooled ADR in individuals with average risk of CRC from 7 studies was 28.2% (95% CI 24.6%-32.0%, I2 = 96.5%). The pooled overall SSL detection rate from 6 studies was 6.3% (95% CI 3.8%-10.5%, I2 = 97%). The included studies were heterogeneous because of differences in the inclusion and exclusion criteria and patient population.

DISCUSSION

In 45- to 49-year-old individuals undergoing a colonoscopy for any indication, the ADR and SSL detection rates were 23.1% and 6.3%, respectively. We conclude that these outcomes in 45- to 49-year-olds are comparable with individuals aged 50-54 years.

Recruitment strategies and consent rates in a national prospective colorectal cancer screening cohort: results from year 1 of the Voyage Study

OBJECTIVE

To identify the optimal incentive protocol for maximising participation while managing study costs during the Voyage trial.

DESIGN

Prospective cohort (Voyage trial) of colorectal cancer (CRC) incidence and mortality outcomes in individuals screened with multitarget stool DNA (mt-sDNA) served as the population. A subset was randomised to receive postage stamps as a pre-consent incentive, or as a post-consent incentive after completion of the consent and questionnaire. Descriptive statistics from year 1 are reported.

RESULTS

During year 1 of the Voyage trial, a total of 600 258 individuals with mt-sDNA orders received at Exact Sciences Laboratories were randomly selected and invited to participate. Of those, 26 429 (4.4%) opted in, 14 365 of whom (54.3%) consented. The opt-in and consent samples were similar to the target population with respect to sex but differed by geographic residence and age (p<0.001). For the embedded incentive experiment, 2333 were randomised to the pre-incentive arm, while 2342 were randomised to the post-incentive arm. Overall consent rate in the incentive trial was 56.4% (60.9% for the pre-consent incentive arm (1421/2333) vs 52.0% for the post-consent incentive arm (1217/2342), p<0.001). Cost reduction was observed for the pre-consent incentive group, and higher response rates were seen among older versus younger individuals.

CONCLUSIONS

Pre-consent incentive option was associated with a higher participation rate and lower costs and was used for the remainder of study recruitment. CRC incidence and mortality vary with age; thus, adjusting for differential participation by age and region will be important in analyses of Voyage data.

TRIAL REGISTRATION NUMBER

NCT04124406.

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.

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

BACKGROUND

Colorectal cancer is the third most diagnosed cancer in adults in the United States. Early detection could prevent more than 90% of colorectal cancer-related deaths, yet more than one third of the screening-eligible population is not up to date with screening despite multiple available tests. A blood-based test has the potential to improve screening adherence, detect colorectal cancer earlier, and reduce colorectal cancer-related mortality.

METHODS

We assessed the performance characteristics of a cell-free DNA (cfDNA) blood-based test in a population eligible for colorectal cancer screening. The coprimary outcomes were sensitivity for colorectal cancer and specificity for advanced neoplasia (colorectal cancer or advanced precancerous lesions) relative to screening colonoscopy. The secondary outcome was sensitivity to detect advanced precancerous lesions.

RESULTS

The clinical validation cohort included 10,258 persons, 7861 of whom met eligibility criteria and were evaluable. A total of 83.1% of the participants with colorectal cancer detected by colonoscopy had a positive cfDNA test and 16.9% had a negative test, which indicates a sensitivity of the cfDNA test for detection of colorectal cancer of 83.1% (95% confidence interval [CI], 72.2 to 90.3). Sensitivity for stage I, II, or III colorectal cancer was 87.5% (95% CI, 75.3 to 94.1), and sensitivity for advanced precancerous lesions was 13.2% (95% CI, 11.3 to 15.3). A total of 89.6% of the participants without any advanced colorectal neoplasia (colorectal cancer or advanced precancerous lesions) identified on colonoscopy had a negative cfDNA blood-based test, whereas 10.4% had a positive cfDNA blood-based test, which indicates a specificity for any advanced neoplasia of 89.6% (95% CI, 88.8 to 90.3). Specificity for negative colonoscopy (no colorectal cancer, advanced precancerous lesions, or nonadvanced precancerous lesions) was 89.9% (95% CI, 89.0 to 90.7).

CONCLUSIONS

In an average-risk screening population, this cfDNA blood-based test had 83% sensitivity for colorectal cancer, 90% specificity for advanced neoplasia, and 13% sensitivity for advanced precancerous lesions. (Funded by Guardant Health; ECLIPSE ClinicalTrials.gov number, NCT04136002.).

Detecting colorectal cancer using genetic and epigenetic biomarkers: screening and diagnosis

Colorectal cancer (CRC) is one of the most frequent types of cancer, with high incidence rates and mortality globally. The extended timeframe for developing CRC allows for the potential screening and early identification of the disease. Furthermore, studies have shown that survival rates for patients with cancer are increased when diagnoses are made at earlier stages. Recent research suggests that the development of CRC, including its precancerous lesion, is influenced not only by genetic factors but also by epigenetic variables. Studies suggest epigenetics plays a significant role in cancer development, particularly CRC. While this approach is still in its early stages and faces challenges due to the variability of CRC, it shows promise as a potential method for understanding and addressing the disease. This review examined the current evidence supporting genetic and epigenetic biomarkers for screening and diagnosis. In addition, we also discussed the feasibility of translating these methodologies into clinical settings. Several markers show promising potential, including the methylation of vimentin (VIM), syndecan-2 (SDC2), and septin 9 (SEPT9). However, their application as screening and diagnostic tools, particularly for early-stage CRC, has not been fully optimized, and their effectiveness needs validation in large, multi-center patient populations. Extensive trials and further investigation are required to translate genetic and epigenetic biomarkers into practical clinical use. biomarkers, diagnostic biomarkers.

Multitarget Stool RNA Test for Colorectal Cancer Screening

Importance

Noninvasive tests for colorectal cancer screening must include sensitive detection of colorectal cancer and precancerous lesions. These tests must be validated for the intended-use population, which includes average-risk individuals 45 years or older.

Objective

To evaluate the sensitivity and specificity of a noninvasive, multitarget stool RNA (mt-sRNA) test (ColoSense) test compared with results from a colonoscopy.

Design, Setting, and Participants

This phase 3 clinical trial (CRC-PREVENT) was a blinded, prospective, cross-sectional study to support a premarket approval application for a class III medical device. A total of 8920 participants were identified online using social media platforms and enrolled from June 2021 to June 2022 using a decentralized nurse call center. All participants completed the mt-sRNA test, which incorporated a commercially available fecal immunochemical test (FIT), concentration of 8 RNA transcripts, and participant-reported smoking status. Stool samples were collected prior to participants completing a colonoscopy at their local endoscopy center. The mt-sRNA test results (positive or negative) were compared with index lesions observed on colonoscopy. Over the course of 12 months, individuals 45 years and older were enrolled in the clinical trial using the decentralized recruitment strategy. Participants were enrolled from 49 US states and obtained colonoscopies at more than 3800 different endoscopy centers.

Main Outcomes and Measures

The primary outcomes included the sensitivity of the mt-sRNA test for detecting colorectal cancer and advanced adenomas and the specificity for no lesions on colonoscopy.

Results

The mean (range) age of participants was 55 (45-90) years, with 4% self-identified as Asian, 11% as Black, and 7% as Hispanic. Of the 8920 eligible participants, 36 (0.40%) had colorectal cancer and 606 (6.8%) had advanced adenomas. The mt-sRNA test sensitivity for detecting colorectal cancer was 94%, sensitivity for detecting advanced adenomas was 46%, and specificity for no lesions on colonoscopy was 88%. The mt-sRNA test showed significant improvement in sensitivity for colorectal cancer (94% vs 78%; McNemar P = .01) and advanced adenomas (46% vs 29%; McNemar P < .001) compared with results of the FIT.

Conclusions and Relevance

In individuals 45 years and older, the mt-sRNA test showed high sensitivity for colorectal neoplasia (colorectal cancer and advanced adenoma) with significant improvement in sensitivity relative to the FIT. Specificity for no lesions on colonoscopy was comparable to existing molecular diagnostic tests.

Trial Registration

ClinicalTrials.gov Identifier: NCT04739722.

Assessment of Stool DNA Markers to Detect Colorectal Neoplasia in Patients with Inflammatory Bowel Disease: A Multi-site Case-control Study

BACKGROUND AND AIMS

The FDA-approved multitarget stool-DNA [mt-sDNA] test is a successful colorectal cancer [CRC] screening tool in average-risk individuals but is not indicated for patients with inflammatory bowel disease [IBD]. We determined the performance of the mt-sDNA assay without the haemoglobin component [mt-sDNAHgb-] in patients with IBD, while measuring sensitivity for colorectal cancer and advanced colorectal neoplasia [ACRN].

METHODS

This was a multi-centre, proof-of-concept investigation in persons aged 18-84 years with a diagnosis of IBD, or primary sclerosing cholangitis [PSC] with IBD. Enrolment occurred between March 2013 and May 2016. Stool was tested with the mt-sDNA molecular markers only, minus the immunochemical haemoglobin component.

RESULTS

The analysis set contained 355 samples. The median age was 52 [range 39-62] years, 45.6% were female and 93% were White. Two-thirds [63%] had ulcerative colitis [UC] and 10.1% had PSC/IBD. Colonoscopy revealed cancer in 8.5% [N = 30], advanced precancerous lesions [APLs] in 9.3% [N = 33] and non-advanced precancerous lesions in 7.6% [N = 27], and three-quarters [74.7%, N = 265] had negative findings. mt-sDNAHgb- sensitivity was 73.3% for any stage cancers, and 76.2% for ACRN. Sensitivity was highest for IBD-associated high-grade dysplasia at 100% and 84.6% for IBD-associated low-grade dysplasia ≥1 cm. The test showed higher sensitivity and lower specificity in UC than in Crohn's disease. Increasing inflammation score was associated with a significant decrease in mt-sDNAHgb- test score [ = 0.028] amongst neoplasia-negative individuals, but not in patients with ACRN.

CONCLUSIONS

These data highlight the potential of multitarget stool-DNA marker testing as an important addition to colorectal cancer surveillance by complementing colonoscopic evaluations in IBD patients.

Current Status and Emerging Trends in Colorectal Cancer Screening and Diagnostics

Colorectal cancer (CRC) is a prevalent and potentially fatal disease categorized based on its high incidences and mortality rates, which raised the need for effective diagnostic strategies for the early detection and management of CRC. While there are several conventional cancer diagnostics available, they have certain limitations that hinder their effectiveness. Significant research efforts are currently being dedicated to elucidating novel methodologies that aim at comprehending the intricate molecular mechanism that underlies CRC. Recently, microfluidic diagnostics have emerged as a pivotal solution, offering non-invasive approaches to real-time monitoring of disease progression and treatment response. Microfluidic devices enable the integration of multiple sample preparation steps into a single platform, which speeds up processing and improves sensitivity. Such advancements in diagnostic technologies hold immense promise for revolutionizing the field of CRC diagnosis and enabling efficient detection and monitoring strategies. This article elucidates several of the latest developments in microfluidic technology for CRC diagnostics. In addition to the advancements in microfluidic technology for CRC diagnostics, the integration of artificial intelligence (AI) holds great promise for further enhancing diagnostic capabilities. Advancements in microfluidic systems and AI-driven approaches can revolutionize colorectal cancer diagnostics, offering accurate, efficient, and personalized strategies to improve patient outcomes and transform cancer management.

Combining methylated SDC2 test in stool DNA, fecal immunochemical test, and tumor markers improves early detection of colorectal neoplasms

Objective

To explore the value of testing methylated SDC2 (SDC2) in stool DNA combined with fecal immunochemical test (FIT) and serum tumor markers (TM) for the early detection of colorectal neoplasms.

Methods

A total of 533 patients, including 150 with CRC (67 with early-stage CRC), 23 with APL, 85 with non-advanced adenomas and general polyps, and 275 with benign lesions and healthy controls. SDC2 was detected by methylation-specific PCR, FIT (hemoglobin, Hb and transferrin, TF) was detected by immunoassay, and the relationships between SDC2, FIT, and clinicopathological features were analyzed. Pathological biopsy or colonoscopy were used as gold standards for diagnosis, and the diagnostic efficacy of SDC2 combined with FIT and TM in CRC and APL evaluated using receiver operating characteristic (ROC) curves.

Results

SDC2 positive rates in early-stage CRC and APL were 77.6% (38/49) and 41.2% (7/17), respectively, and combination of SDC2 with FIT increased the positive rates to 98.0% (48/49) and 82.4% (14/17). The positive rates of SDC2 combined with FIT assay in the APL and CRC groups at stages 0-IV were 82.4% (14/17), 85.7% (6/7), 100% (16/16), 100% (26/26), 97.4% (38/39), and 100% (22/22), respectively. Compared to the controls, both the CRC and APL groups showed significantly higher positive detection rates of fecal SDC2 and FIT (χ2 = 114.116, P < 0.0001 and χ2 = 85.409, P < 0.0001, respectively). Our results demonstrate a significant difference in the qualitative methods of SDC2 and FIT for the detection of colorectal neoplasms (McNemar test, P < 0.0001). ROC curve analysis revealed that the sensitivities of SDC2 and FIT, alone or in combination, for the detection of early CRC and APL were 69.9%, 86.3%, and 93.9%, respectively (all P<0.0001). When combined with CEA, the sensitivity increased to 97.3% (P<0.0001).

Conclusions

SDC2 facilitates colorectal neoplasms screening, and when combined with FIT, it enhances detection. Furthermore, the combination of SDC2 with FIT and CEA maximizes overall colorectal neoplasm detection.

Multitarget Stool DNA Testing Has High Positive Predictive Value for Colorectal Neoplasia on the Second Round of Testing

BACKGROUND & AIMS

Multitarget stool DNA (mt-sDNA) testing is a stool-based screening test for colorectal cancer (CRC). In a single instance of testing, the pivotal Food and Drug Administration-approval study (NCT01397747) found that 16% of mt-sDNA tests were positive, and the positive predictive value (PPV) for CRC or advanced precursor lesions (APL) was 27.3%. We aimed to examine real-world longitudinal performance by determining the test-positive rate and PPV of mt-sDNA on the second round of testing.

METHODS

Colonoscopy and pathology reports were reviewed retrospectively for patients with a negative mt-sDNA on the first round of screening and a positive mt-sDNA on the second round. The test-positivity rate and PPV for CRC, APL, and any colorectal neoplasia were calculated for the second mt-sDNA and compared with baseline PPVs from a previously published cohort of patients from our institution who tested positive on the first round of screening.

RESULTS

A total of 2758 patients completed a second test at a median of 3.2 years after the first test. Of these, 422 (15%) had a positive second mt-sDNA. The PPV was 0.25% for CRC, 24% for APL, and 67% for any colorectal neoplasia. There was no significant difference in PPV on the second mt-sDNA test compared with the first round (24% vs 28% for APL; P = .12).

CONCLUSIONS

mt-sDNA test positive rate and PPV were similar between the first and second rounds of screening. These observations confirm the utility of a second round of mt-sDNA screening and may inform estimates of mt-sDNA effectiveness for CRC screening.

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.

Application and development of noninvasive biomarkers for colorectal cancer screening: a systematic review

BACKGROUND

Colorectal cancer (CRC) is the second most common cause of cancer-related death (9.4% of the 9.9 million cancer deaths). However, CRC develops slowly, and early detection and intervention can effectively improve the survival rate and quality of life. Although colonoscopy can detect and diagnose CRC, it is unsuitable for CRC screening in average-risk populations. Some commercial kits based on DNA mutation or methylation are approved for screening, but the low sensitivity for advanced adenoma or early-stage CRC would limit the applications.

MAIN RESULTS

Recently, researchers have focused on developing noninvasive or minimally invasive, easily accessible biomarkers with higher sensitivity and accuracy for CRC screening. Numerous reports describe advances in biomarkers, including DNA mutations and methylation, mRNA and miRNA, gut microbes, and metabolites, as well as low-throughput multiomics panels. In small cohorts, the specificity and sensitivity improved when fecal immunochemical testing combined with other biomarkers; further verification in large cohorts is expected. In addition, the continuous improvement of laboratory technology has also improved the sensitivity of detection technology, such as PCR, and the application of CRISPR/Cas technology. Besides, artificial intelligence has extensively promoted the mining of biomarkers. Machine learning was performed to construct a diagnosis model for CRC screening based on the cfDNA fragment features from whole-genome sequencing data. In another study, multiomics markers, including cfDNA, epigenetic, and protein signals, were also discovered by machine learning. Finally, advancements in sensor technology promote the applicability of volatile organic compounds in CRC early detection.

CONCLUSION

Here, the authors review advances in early detection and screening of CRC based on different biomarker types. Most studies reported optimistic findings based on preliminary research, and prospective clinical studies are ongoing. These promising biomarkers are expected to more accurately identify early-stage patients with CRC and be applied in the future.

Potential prognostic and predictive value of UBE2N, IMPDH1, DYNC1LI1 and HRASLS2 in colorectal cancer stool specimens

Colorectal cancer (CRC) is the most common gastrointestinal malignancy worldwide. The poor specificity and sensitivity of the fecal occult blood test has prompted the development of CRC-related genetic markers for CRC screening and treatment. Gene expression profiles in stool specimens are effective, sensitive and clinically applicable. Herein, a novel advantage of using cells shed from the colon is presented for cost-effective CRC screening. Molecular panels were generated through a series of leave-one-out cross-validation and discriminant analyses. A logistic regression model following reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and immunohistochemistry was used to validate a specific panel for CRC prediction. The panel, consisting of ubiquitin-conjugating enzyme E2 N (UBE2N), inosine monophosphate dehydrogenase 1 (IMPDH1), dynein cytoplasmic 1 light intermediate chain 1 (DYNC1LI1) and phospholipase A and acyltransferase 2 (HRASLS2), accurately recognized patients with CRC and could thus be further investigated as a potential prognostic and predictive biomarker for CRC. UBE2N, IMPDH1 and DYNC1LI1 expression levels were upregulated and HRASLS2 expression was downregulated in CRC tissues. The predictive power of the panel was 96.6% [95% confidence interval (CI), 88.1-99.6%] sensitivity and 89.7% (95% CI, 72.6-97.8%) specificity at a predicted cut-off value at 0.540, suggesting that this four-gene panel testing of stool specimens can faithfully mirror the state of the colon. On the whole, the present study demonstrates that screening for CRC or cancer detection in stool specimens collected non-invasively does not require the inclusion of an excessive number of genes, and colonic defects can be identified via the detection of an aberrant protein in the mucosa or submucosa.

Regulation of Laboratory-Developed Tests in Preventive Oncology: Emerging Needs and Opportunities

Cancer predictive or diagnostic assays, offered as Laboratory-Developed Tests (LDTs), have been subject to regulatory authority and enforcement discretion by the US Food and Drug Administration. Many LDTs enter the market without US Food and Drug Administration or any regulatory review. The Centers for Medicare & Medicaid Services under the Clinical Laboratory Improvement Amendments focuses on analytic performance, but has limited oversight of the quality or utility of LDTs, including whether patients have been harmed as a result of their use. Increasingly, LDTs for cancer risk or early detection have been marketed directly to consumers, with many LDT developers depicting these tests, requested by patients but ordered by personal or company-associated physicians, as procedures falling under the practice of medicine. This patchwork of regulation and enforcement uncertainty regarding LDTs and public concerns about accuracy of tests given emergency authorization during the COVID-19 pandemic led to the Verifying Accurate Leading-edge IVCT (in vitro clinical test) Development Act of 2021. This pending federal legislation represents an opportunity to harmonize regulatory policies and address growing concerns over quality, utility, and safety of LDTs for cancer genomics, including tests marketed directly to consumers. We review here questions regarding the potential benefits and harms of some cancer-related LDTs for cancer risk and presymptomatic molecular diagnosis, increasingly marketed to oncologists or directly to the worried well. We offer specific proposals to strengthen oversight of the accuracy and clinical utility of cancer genetic testing to ensure public safety.

Colonoscopy after a Positive Stool-based Test for Colon Cancer Screening: Moving Toward a Better Understanding of What to Expect

Stool-based tests for colorectal cancer, including fecal immunochemical testing (FIT) and multitarget stool DNA testing (mt-sDNA), are among the recommended first-line screening options for patients at average risk for colorectal cancer and offer advantages over colonoscopy. However, stool-based tests have high false-positive rates, and the expected yield of colonoscopy after positive FIT compared with positive mt-sDNA is not well studied. As discussed in this issue of Cancer Prevention Research, the presence of a precancerous lesion in the majority of cases with either positive stool-based test is expected. In addition, a positive mt-sDNA is associated with a higher risk for finding any neoplasia on colonoscopy compared with positive FIT, and particularly associated with higher prevalence of clinically relevant serrated polyps compared with positive FIT. Further research is needed on what to expect from positive stool-based testing on average risk 45-49 years old patients, the newest cohort indicated for colorectal cancer screening. See related article, p. 455.

Prevalence and Predictors of Young-Onset Colorectal Neoplasia: Insights From a Nationally Representative Colonoscopy Registry

BACKGROUND & AIMS

A disturbing increase in early-onset colorectal cancer (EOCRC) has prompted recent guidelines to recommend lowering the colorectal cancer (CRC) screening starting age from 50 to 45 years old for average-risk individuals. Little is known about the prevalence of colorectal neoplasia in individuals between 45 and 49 years old, or even younger, in the United States. We analyzed a large, nationally representative data set of almost 3 million outpatient colonoscopies to determine the prevalence of, and risk factors for, colorectal neoplasia among patients aged 18 to 54.

METHODS

Findings from high-quality colonoscopies were analyzed from AMSURG ambulatory endoscopy centers (ASCs) that report their results in the GI Quality Improvement Consortium (GIQuIC) Registry. Logistic regression was used to identify risk factors for EOCRC.

RESULTS

Increasing age, male sex, White race, family history of CRC, and examinations for bleeding or screening were all associated with higher odds of advanced premalignant lesions (APLs) and CRC. Among patients aged 45 to 49, 32% had any neoplasia, 7.5% had APLs, and 0.58% had CRC. Rates were almost as high in those aged 40 to 44. Family history of CRC portended neoplasia rates 5 years earlier. Rates of APLs were higher in American Indian/Alaskan Natives, but lower among Blacks, Asians, and Hispanics, compared with White counterparts. The prevalence of any neoplasia and APL gradually increased between 2014 and 2019, in all age groups.

CONCLUSIONS

These data provide support for lowering the screening age to 45 for all average-risk individuals. Early messaging to patients and providers in the years leading up to age 45 is warranted, especially in those with a family history of CRC.

A Practical Overview of the Stool DNA Test for Colorectal Cancer Screening

The multitarget stool DNA test with fecal immunochemical test (sDNA-FIT) is recommended by all major US guidelines as an option for colorectal cancer screening. It is approved by the Food and Drug Administration for use in average-risk individuals aged 45 years and older. The sDNA-FIT tests for 11 biomarkers, including point mutations in KRAS, aberrant methylation in NDRG4 and BMP3, and human hemoglobin. Patients collect a stool sample at home, send it to the manufacturer's laboratory within 1 day, and the result is reported in approximately 2 weeks. Compared with FIT, sDNA-FIT has higher sensitivity but lower specificity for colorectal cancer, which translates to a higher false-positive rate. A unique feature of sDNA-FIT is the manufacturer's comprehensive patient navigation system, which operates 24 hours a day and provides active outreach for patient education and reminders in the first month after a test is ordered. Retesting is recommended every 1-3 years, although the optimal testing interval has not yet been determined empirically. The cost of sDNA-FIT is $681 without insurance, but Medicare and most private insurers cover it with no copay or deductible.

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.

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

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

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

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

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

Updates on Age to Start and Stop Colorectal Cancer Screening: Recommendations From the U.S. Multi-Society Task Force on Colorectal Cancer

This document is a focused update to the 2017 colorectal cancer (CRC) screening recommendations from the U.S. Multi-Society Task Force on Colorectal Cancer, which represents the American College of Gastroenterology, the American Gastroenterological Association, and the American Society for Gastrointestinal Endoscopy. This update is restricted to addressing the age to start and stop CRC screening in average-risk individuals and the recommended screening modalities. Although there is no literature demonstrating that CRC screening in individuals under age 50 improves health outcomes such as CRC incidence or CRC-related mortality, sufficient data support the U.S. Multi-Society Task Force to suggest average-risk CRC screening begin at age 45. This recommendation is based on the increasing disease burden among individuals under age 50, emerging data that the prevalence of advanced colorectal neoplasia in individuals ages 45 to 49 approaches rates in individuals 50 to 59, and modeling studies that demonstrate the benefits of screening outweigh the potential harms and costs. For individuals ages 76 to 85, the decision to start or continue screening should be individualized and based on prior screening history, life expectancy, CRC risk, and personal preference. Screening is not recommended after age 85.

Updates on Age to Start and Stop Colorectal Cancer Screening: Recommendations From the U.S. Multi-Society Task Force on Colorectal Cancer

This document is a focused update to the 2017 colorectal cancer (CRC) screening recommendations from the U.S. Multi-Society Task Force on Colorectal Cancer, which represents the American College of Gastroenterology, the American Gastroenterological Association, and the American Society for Gastrointestinal Endoscopy. This update is restricted to addressing the age to start and stop CRC screening in average-risk individuals and the recommended screening modalities. Although there is no literature demonstrating that CRC screening in individuals under age 50 improves health outcomes such as CRC incidence or CRC-related mortality, sufficient data support the U.S. Multi-Society Task Force to suggest average-risk CRC screening begin at age 45. This recommendation is based on the increasing disease burden among individuals under age 50, emerging data that the prevalence of advanced colorectal neoplasia in individuals ages 45 to 49 approaches rates in individuals 50 to 59, and modeling studies that demonstrate the benefits of screening outweigh the potential harms and costs. For individuals ages 76 to 85, the decision to start or continue screening should be individualized and based on prior screening history, life expectancy, CRC risk, and personal preference. Screening is not recommended after age 85.

Updates on age to start and stop colorectal cancer screening: recommendations from the U.S. Multi-Society Task Force on Colorectal Cancer

This document is a focused update to the 2017 colorectal cancer (CRC) screening recommendations from the U.S. Multi-Society Task Force on Colorectal Cancer, which represents the American College of Gastroenterology, the American Gastroenterological Association, and the American Society for Gastrointestinal Endoscopy. This update is restricted to addressing the age to start and stop CRC screening in average-risk individuals and the recommended screening modalities. Although there is no literature demonstrating that CRC screening in individuals under age 50 improves health outcomes such as CRC incidence or CRC-related mortality, sufficient data support the U.S. Multi-Society Task Force to suggest average-risk CRC screening begin at age 45. This recommendation is based on the increasing disease burden among individuals under age 50, emerging data that the prevalence of advanced colorectal neoplasia in individuals ages 45 to 49 approaches rates in individuals 50 to 59, and modeling studies that demonstrate the benefits of screening outweigh the potential harms and costs. For individuals ages 76 to 85, the decision to start or continue screening should be individualized and based on prior screening history, life expectancy, CRC risk, and personal preference. Screening is not recommended after age 85.

Noninvasive fecal testing for colorectal cancer

INTRODUCTION

Colorectal cancer (CRC) is the third most common malignancy worldwide, with the second highest mortality rate among all malignancies. In this review, we describe the current utility of stool diagnostic biomarkers for CRC.

METHODS

We reviewed stool-related tests and biomarker candidates for the diagnosis of CRC. The guaiac-based fecal occult blood test (gFOBT), fecal immunochemical test (FIT), and multitarget stool DNA test (MT-sDNA) have been used as clinical CRC screening tools. Although microRNAs, protein biomarkers, and microbiota have not yet been used in clinical CRC screening, there is growing evidence that they have the potential to function as CRC screening tools.

RESULTS

According to the literature, the sensitivity of MT-sDNA for detecting CRC was 87.0-100%, 32.7-82.0% for advanced adenomas, and the specificity was 86.1-95.2%. The sensitivity of individual biomarkers of fecal microRNAs for detecting CRC was 34.2-88.2%, 73.0% for advanced adenomas, and the specificity was 68-100%. The sensitivity of fecal protein markers for detecting CRC was 63.6-93.0%, 47.7-69.4% for advanced adenomas, and the specificity was 38.3-97.5%. The sensitivity of fecal microbiota for detecting CRC was 54.0-100.0%, 32.0-48.3% for advanced adenomas, and the specificity was 61.3-90.0%.

CONCLUSION

MT-sDNA is the most sensitive CRC screening test, and its sensitivity is the highest for advanced adenomas; however, its detection cost is high. MT-sDNA was more sensitive to CRC and advanced precancerous lesions than FIT, but compared to three years of MT-sDNA, annual FIT as the first non-invasive screening test for CRC seemed to be more effective.

Lowering the colorectal cancer screening age improves predicted outcomes in a microsimulation model

AIMS

While most guidelines still recommend colorectal cancer (CRC) screening initiation at age 50 years in average-risk individuals, guideline-creating bodies are starting to lower the recommended age of initiation to 45 years to mitigate the trend of increasing CRC rates in younger populations. Using CRC-AIM, we modeled the impact of lowering the CRC screening initiation age, incorporating theoretical and reported adherence rates, for triennial multi-target stool DNA (mt-sDNA) or annual fecal immunochemical test (FIT) screening.

METHODS AND MATERIALS

Screening strategies were simulated for individuals without CRC at age 40 and screened from ages 50 to 75 or 45 to 75 years. Outcomes included CRC incidence, CRC mortality, and life-years gained (LYG) per 1000 individuals screened (compared with no screening). Models used theoretically perfect (100%) and previously reported (71% mt-sDNA; 43% FIT) adherence rates.

RESULTS

With perfect adherence, mt-sDNA and FIT resulted in 22.2 and 23.4 more predicted LYG, respectively, with screening initiation at age 45 versus 50 years; reported adherence resulted in 23.9 and 24.4 more LYG, respectively. With perfect adherence, screening initiation at age 45 versus 50 years resulted in 26.1 and 28.6 CRC cases, respectively, with mt-sDNA and 22.8 and 25.5 cases with FIT; with reported real-world adherence there were 28.5 and 31.2 cases, respectively, with mt-sDNA and 37.1 and 40.2 cases with FIT. Similar patterns were observed for CRC deaths. With screening initiation at age 45 and reported adherence, mt-sDNA averted 8.6 more CRC cases and 3.3 more deaths per 1000 individuals than FIT.

CONCLUSIONS

Estimated CRC screening outcomes improved by lowering the initiation age from 50 to 45 years. Incorporating reported adherence rates yields greater benefits from triennial mt-sDNA versus annual FIT screening.

Screening for Colorectal Cancer: Updated Evidence Report and Systematic Review for the US Preventive Services Task Force

IMPORTANCE

Colorectal cancer (CRC) remains a significant cause of morbidity and mortality in the US.

OBJECTIVE

To systematically review the effectiveness, test accuracy, and harms of screening for CRC to inform the US Preventive Services Task Force.

DATA SOURCES

MEDLINE, PubMed, and the Cochrane Central Register of Controlled Trials for relevant studies published from January 1, 2015, to December 4, 2019; surveillance through March 26, 2021.

STUDY SELECTION

English-language studies conducted in asymptomatic populations at general risk of CRC.

DATA EXTRACTION AND SYNTHESIS

Two reviewers independently appraised the articles and extracted relevant study data from fair- or good-quality studies. Random-effects meta-analyses were conducted.

MAIN OUTCOMES AND MEASURES

Colorectal cancer incidence and mortality, test accuracy in detecting cancers or adenomas, and serious adverse events.

RESULTS

The review included 33 studies (n = 10 776 276) on the effectiveness of screening, 59 (n = 3 491 045) on the test performance of screening tests, and 131 (n = 26 987 366) on the harms of screening. In randomized clinical trials (4 trials, n = 458 002), intention to screen with 1- or 2-time flexible sigmoidoscopy vs no screening was associated with a decrease in CRC-specific mortality (incidence rate ratio, 0.74 [95% CI, 0.68-0.80]). Annual or biennial guaiac fecal occult blood test (gFOBT) vs no screening (5 trials, n = 419 966) was associated with a reduction of CRC-specific mortality after 2 to 9 rounds of screening (relative risk at 19.5 years, 0.91 [95% CI, 0.84-0.98]; relative risk at 30 years, 0.78 [95% CI, 0.65-0.93]). In observational studies, receipt of screening colonoscopy (2 studies, n = 436 927) or fecal immunochemical test (FIT) (1 study, n = 5.4 million) vs no screening was associated with lower risk of CRC incidence or mortality. Nine studies (n = 6497) evaluated the test accuracy of screening computed tomography (CT) colonography, 4 of which also reported the test accuracy of colonoscopy; pooled sensitivity to detect adenomas 6 mm or larger was similar between CT colonography with bowel prep (0.86) and colonoscopy (0.89). In pooled values, commonly evaluated FITs (14 studies, n = 45 403) (sensitivity, 0.74; specificity, 0.94) and stool DNA with FIT (4 studies, n = 12 424) (sensitivity, 0.93; specificity, 0.85) performed better than high-sensitivity gFOBT (2 studies, n = 3503) (sensitivity, 0.50-0.75; specificity, 0.96-0.98) to detect cancers. Serious harms of screening colonoscopy included perforations (3.1/10 000 procedures) and major bleeding (14.6/10 000 procedures). CT colonography may have harms resulting from low-dose ionizing radiation. It is unclear if detection of extracolonic findings on CT colonography is a net benefit or harm.

CONCLUSIONS AND RELEVANCE

There are several options to screen for colorectal cancer, each with a different level of evidence demonstrating its ability to reduce cancer mortality, its ability to detect cancer or precursor lesions, and its risk of harms.

An examination of socioeconomic and racial/ethnic disparities in the awareness, knowledge and utilization of three colorectal cancer screening modalities

While colorectal cancer (CRC) mortality rates have been decreasing, disparities by socioeconomic status (SES) and race/ethnicity persist. CRC screening rates remain suboptimal among low SES and racial/ethnic minority populations, despite the availability of multiple screening modalities. Understanding awareness, knowledge, and utilization of common screening modalities within different racial/ethnic and SES groups is critical to inform efforts to improve population screening uptake and reduce disparities in CRC-related health outcomes. Through the theoretical lenses of diffusion of innovation and fundamental cause theory, we examined the associations of race/ethnicity and SES with awareness, knowledge, and utilization of three guideline recommended CRC screening strategies among individuals at average risk for CRC. Data were obtained from a survey of a nationally representative panel of US adults conducted in November 2019. The survey was completed by 31.3% of invited panelists (1595 of 5097). Analyses were focused on individuals at average risk for CRC, aged 45–75 for awareness and knowledge outcomes (n = 1062) and aged 50–75 for utilization outcomes (n = 858). Analyses revealed racial/ethnic and SES disparities among the three CRC screening modalities, with more racial/ethnic and SES differences observed in the awareness, knowledge, and utilization of screening colonoscopy and mt-sDNA than FIT/gFOBT. Patterns of disparities are consistent with previous research showing that inequities in social and economic resources are associated with an imbalanced adoption of medical innovations. Our findings demonstrate a need to increase awareness, knowledge, and access of various CRC screening modalities in specific populations defined by race/ethnicity or SES indicators. Efforts to increase CRC screening should be tailored to the needs and social-cultural context of populations. Interventions addressing inequalities in social and economic resources are also needed to achieve more equitable adoption of CRC screening modalities and reduce disparities in CRC-related health outcomes.

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Socioeconomic status linked to screening method awareness gap, notably mt-sDNA.

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Screening modalities with low demand on patient resources more likely to be adopted.

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Screening education needs to emphasize uniform starting age for all modalities.

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Tailoring education to low resource communities may improve screening uptake.