Advanced Precancerous Lesions Research Articles

Algorithm Development and Early Performance Evaluation of a Next-generation Multitarget Stool DNA Screening Test for Colorectal Cancer

Background and AimsThe multitarget stool DNA (mt-sDNA) assay is a non-invasive average-risk colorectal cancer (CRC) screening test. A new biomarker panel was developed for a next-generation test to improve specificity while maintaining/increasing sensitivity. We aimed first to establish an algorithm and cutoff for the next-generation mt-sDNA test and then to validate it using archived samples from the pivotal DeeP-C study (NCT01397747) of the first-generation test. MethodsAlgorithm development and cross-validation included 3011 samples from 2 specimen collection studies (NCT03821948, NCT03789162). The algorithm and cutoff were locked before validation. Validation test set samples included 57 CRC, 583 advanced precancerous lesions (APLs), and 7022 samples negative for CRC or APLs from the DeeP-C study, which prospectively enrolled average-risk, asymptomatic adults aged 50 to 84 years before screening colonoscopy. Next-generation biomarkers included methylated DNA markers LASS4, LRRC4, PPP2R5C, and ZDHHC1 (reference marker), and fecal hemoglobin. Primary validation endpoints were CRC sensitivity and specificity for the absence of advanced neoplasia. Secondary endpoints included APL sensitivity and specificity for non-neoplastic findings or negative colonoscopy. ResultsCross-validation and best-fit results from algorithm development closely matched, confirming algorithm reliability and reproducibility. For the test set, next-generation mt-sDNA test sensitivity was 93.0% (95% CI, 83.0%-98.1%) for CRC and 48.4% (95% CI, 44.2%-52.5%) for APLs. Specificity was 88.5% (95% CI, 87.7%-89.2%) for the absence of advanced neoplasia and 90.4% (95% CI, 89.5%-91.2%) for the combination of non-neoplastic findings or negative colonoscopy. ConclusionsBased on archived samples, the next-generation mt-sDNA test demonstrated promising CRC screening performance characteristics that will be further assessed in a prospective clinical validation study (BLUE-C; NCT04144738).

Stool Glycoproteomics Signatures of Pre-Cancerous Lesions and Colorectal Cancer.

Colorectal cancer (CRC) screening relies primarily on stool analysis to identify occult blood. However, its sensitivity for detecting precancerous lesions is limited, requiring the development of new tools to improve CRC screening. Carcinogenesis involves significant alterations in mucosal epithelium glycocalyx that decisively contribute to disease progression. Building on this knowledge, we examined patient series comprehending premalignant lesions, colorectal tumors, and healthy controls for the T-antigen-a short-chain O-glycosylation of proteins considered a surrogate marker of malignancy in multiple solid cancers. We found the T-antigen in the secretions of dysplastic lesions as well as in cancer. In CRC, T-antigen expression was associated with the presence of distant metastases. In parallel, we analyzed a broad number of stools from individuals who underwent colonoscopy, which showed high T expressions in high-grade dysplasia and carcinomas. Employing mass spectrometry-based lectin-affinity enrichment, we identified a total of 262 proteins, 67% of which potentially exhibited altered glycosylation patterns associated with cancer and advanced pre-cancerous lesions. Also, we found that the stool (glyco)proteome of pre-cancerous lesions is enriched for protein species involved in key biological processes linked to humoral and innate immune responses. This study offers a thorough analysis of the stool glycoproteome, laying the groundwork for harnessing glycosylation alterations to improve non-invasive cancer detection.

Immunoexpression of Ki67, P16 and Beta-catenin in precursor lesions of cutaneous squamous cell carcinoma.

Cutaneous squamous cell carcinoma (CSCC) is the second most common type of skin cancer, after basal cell carcinoma, representing about 10-20% of all malignant skin tumors. The mortality rates of CSCC approach those of renal and oropharyngeal carcinomas, as well as melanoma, with the increasing of the risk once metastases and perineural invasion occur. Both actinic keratosis (AK) and Bowen's disease (BD) are direct precursors with the potential for progression to CSCC. In this study, we analyzed the expression of Ki67, P16 and Beta-catenin in the precursor lesions of CSCC in relation to histological prognostic parameters, respectively between them, with the aim of identifying possible correlations with a role in prognosis. Ki67 and P16 presented higher scores in advanced precancerous lesions, such as keratinocyte intraepithelial neoplasia (KIN) III and BD and low scores in seborrheic keratosis (SK). The immunoreactivity to the investigated markers confirms the multistage skin carcinogenesis, and their involvement starting from the initiation phase of the cancer process. The importance of the studied markers in the evolution and prognosis of precancerous lesions of CSCC is also supported by the linear correlations revealed between the immunoexpressions of P16, Ki67 and the membranous immunoexpression of Beta-catenin in AK.

Abstract 1063: IsomiR relative proportion (IRP) within miRNA family as an efficient biomarker for noninvasive colorectal cancer detection

Abstract Background: Cell free miRNA has been widely used for disease diagnosis, particularly in cancers. The latest research has also demonstrated that isomiRs (isoform miRNAs) can serve as superior markers, displaying enhanced diagnostic performance in cancer diagnosis. However, the low detection sensitivities of miRNA/isomiRs in previous methods in plasma have limited their broad implementations for screening purpose. In this study, we propose a new isomiRs feature of isomiR relative proportion (IRP), which was validated with high performance in Colorectal Cancer (CRC) early diagnosis. Methods: A total of 1036 participants were enrolled from the National Colorectal Cancer Cohort (NCRCC), and 836 participants were eligible for plasma collection, including 238 controls, 373 CRC patients, 41 inflammatory bowel disease (IBD), 5 intramucosal carcinoma (Tis) and 179 advanced precancerous lesions (APL). Total circulating small RNA was extracted, followed by library preparation using UMI-based approach. Subsequently, small RNA sequencing was conducted using DNB-seq, and bioinformatic analysis was performed thereafter. The samples were randomly assigned into training (49%), test (30%) and validation (21%) sets. Models based on isomiR relative proportion (IRP), isomiR relative expression (IRE) or both features were constructed by beam search and random forest algorithms in training and test sets, and results were verified in validation set. Results: Differential IRP or IRE features were identified between cancer and controls. IRP identified 132 specific differential expressed isomiRs. Models constructed using either IRP or IRE features showed high performance (both AUC > 0.9). However, there was improvement in IRP feature model in the validation set (sensitivity of IRP: 0.923, sensitivity of IRE: 0.859) compared with IRE model. We then found that there may be complementarities between IRP and IRE features, and the combination model (34 IRP+IRE features) improved cancer detection performance (AUC: 0.953). Finally, the risk scores predicted by this combination model increased gradually across CRC progression (R=0.921), and the sensitivity of APL was 0.626. Conclusion: We improved the small-RNA sequencing method and developed an IRP method, and present that IRP as a new feature not only demonstrate the ability of CRC early detection, but also revealed the CRC progressing process. Besides, the combination of IRP and IRE improved the performance of diagnosis. These results highlight the potential value of the IRP feature in early cancer detection. Citation Format: Yeting Hu, Wei Lu, Chengcheng Liu, Xiaozhuan Dai, Jiasheng Xu, Xiangxing Kong, Yunfeng Zhu, Yao Ye, Lihao Chen, Xiaolong An, Fan Wu, Shiqing Ma, Nana Wang, Qian Xiao, Jun Liu, Kefeng Ding. IsomiR relative proportion (IRP) within miRNA family as an efficient biomarker for noninvasive colorectal cancer detection [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1063.

Next-Generation Multitarget Stool DNA Test for Colorectal Cancer Screening

BackgroundA next-generation multitarget stool DNA test, including assessments of DNA molecular markers and hemoglobin level, was developed to improve the performance of colorectal cancer screening, primarily with regard to specificity.MethodsIn a prospective study, we evaluated a next-generation multitarget stool DNA test in asymptomatic adults 40 years of age or older who were undergoing screening colonoscopy. The primary outcomes were sensitivity of the test for colorectal cancer and specificity for advanced neoplasia (colorectal cancer or advanced precancerous lesions). Advanced precancerous lesions included one or more adenomas or sessile serrated lesions measuring at least 1 cm in the longest dimension, lesions with villous histologic features, and high-grade dysplasia. Secondary objectives included the quantification of sensitivity for advanced precancerous lesions and specificity for nonneoplastic findings or negative colonoscopy and comparison of sensitivities for colorectal cancer and advanced precancerous lesions between the multitarget stool DNA test and a commercially available fecal immunochemical test (FIT).ResultsOf 20,176 participants, 98 had colorectal cancer, 2144 had advanced precancerous lesions, 6973 had nonadvanced adenomas, and 10,961 had nonneoplastic findings or negative colonoscopy. With the next-generation test, sensitivity for colorectal cancer was 93.9% (95% confidence interval [CI], 87.1 to 97.7), and specificity for advanced neoplasia was 90.6% (95% CI, 90.1 to 91.0). Sensitivity for advanced precancerous lesions was 43.4% (95% CI, 41.3 to 45.6), and specificity for nonneoplastic findings or negative colonoscopy was 92.7% (95% CI, 92.2 to 93.1). With the FIT, sensitivity was 67.3% (95% CI, 57.1 to 76.5) for colorectal cancer and 23.3% (95% CI, 21.5 to 25.2) for advanced precancerous lesions; specificity was 94.8% (95% CI, 94.4 to 95.1) for advanced neoplasia and 95.7% (95% CI, 95.3 to 96.1) for nonneoplastic findings or negative colonoscopy. As compared with FIT, the next-generation test had superior sensitivity for colorectal cancer (P<0.001) and for advanced precancerous lesions (P<0.001) but had lower specificity for advanced neoplasia (P<0.001). No adverse events occurred.ConclusionsThe next-generation multitarget stool DNA test showed higher sensitivity for colorectal cancer and advanced precancerous lesions than FIT but also showed lower specificity. (Funded by Exact Sciences; BLUE-C ClinicalTrials.gov number, NCT04144738.)

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

BackgroundColorectal 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.MethodsWe 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.ResultsThe 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).ConclusionsIn 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.)

Population-based screening for colorectal cancer in Wuhan, China.

https://www.chictr.org.cn/showproj.html?proj=192838, identifier ChiCTR2300070520.

A proteomic classifier panel for early screening of colorectal cancer: a case control study

BackgroundDiagnosis of colorectal cancer (CRC) during early stages can greatly improve patient outcome. Although technical advances in the field of genomics and proteomics have identified a number of candidate biomarkers for non-invasive screening and diagnosis, developing more sensitive and specific methods with improved cost-effectiveness and patient compliance has tremendous potential to help combat the disease.MethodsWe enrolled three cohorts of 479 subjects, including 226 CRC cases, 197 healthy controls, and 56 advanced precancerous lesions (APC). In the discovery cohort, we used quantitative mass spectrometry to measure the expression profile of plasma proteins and applied machine-learning to select candidate proteins. We then developed a targeted mass spectrometry assay to measure plasma concentrations of seven proteins and a logistic regression classifier to distinguish CRC from healthy subjects. The classifier was further validated using two independent cohorts.ResultsThe seven-protein panel consisted of leucine rich alpha-2-glycoprotein 1 (LRG1), complement C9 (C9), insulin-like growth factor binding protein 2 (IGFBP2), carnosine dipeptidase 1 (CNDP1), inter-alpha-trypsin inhibitor heavy chain 3 (ITIH3), serpin family A member 1 (SERPINA1), and alpha-1-acid glycoprotein 1 (ORM1). The panel classified CRC and healthy subjects with high accuracy, since the area under curve (AUC) of the training and testing cohort reached 0.954 and 0.958. The AUC of the two independent validation cohorts was 0.905 and 0.909. In one validation cohort, the panel had an overall sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 89.9%, 81.8%, 89.2%, and 82.9%, respectively. In another blinded validation cohort, the panel classified CRC from healthy subjects with a sensitivity of 81.5%, specificity of 97.9%, and overall accuracy of 92.0%. Finally, the panel was able to detect APC with a sensitivity of 49%.ConclusionsThis seven-protein classifier is a clear improvement compared to previously published blood-based protein biomarkers for detecting early-stage CRC, and is of translational potential to develop into a clinically useful assay.

Increased infiltration of CD4+ IL-17A+ FOXP3+ T cells in Helicobacter pylori-induced gastritis.

Helicobacter pylori is one of the main predisposing factors for gastric cancer, causing chronic inflammation and proper glands atrophy in the gastric mucosa. Although H. pylori-induced inflammation is a key inducer of precancerous lesions in the gastric mucosa, it remains unclear which precise immune cell subsets are responsible for the progression of H. pylori-induced gastritis. Here, we observed an abundance of CD4+ IL-17A+ FOXP3+ T cells exhibiting a Th17-like phenotype within the microenvironment of H. pylori-induced gastritis. Mechanistically, H. pylori upregulated the expression of IL-6 in Dendritic cells and macrophages, by activating NF-κB signaling through the virulence factor CagA and thus, induced IL-17A expression in FOXP3+ T cells. Moreover, CD4+ IL-17A+ FOXP3+ T cells were positively associated with advanced precancerous lesions. Therefore, these findings offer essential insights into how FOXP3+ T cells sense inflammatory signals from the environment, such as IL-6, during H. pylori infections, thereby guiding the effector immune response and aggravating the gastritis.

Next-generation Multi-target Stool DNA Panel Accurately Detects Colorectal Cancer and Advanced Precancerous Lesions.

This study highlights performance of the next-generation mt-sDNA test, which exhibits high sensitivity and specificity for detecting colorectal cancer and APLs. This noninvasive option has potential to increase screening participation and clinical outcomes. A multi-center, clinical validation trial is underway. See related commentary by Bresalier, p. 93.

Global metabolomics revealed deviations from the metabolic aging clock in colorectal cancer patients.

Background: Markers of aging hold promise in the context of colorectal cancer (CRC) care. Utilizing high-resolution metabolomic profiling, we can unveil distinctive age-related patterns that have the potential to predict early CRC development. Our study aims to unearth a panel of aging markers and delve into the metabolomic alterations associated with aging and CRC. Methods: We assembled a serum cohort comprising 5,649 individuals, consisting of 3,002 healthy volunteers, 715 patients diagnosed with colorectal advanced precancerous lesions (APL), and 1,932 CRC patients, to perform a comprehensive metabolomic analysis. Results: We successfully identified unique age-associated patterns across 42 metabolic pathways. Moreover, we established a metabolic aging clock, comprising 9 key metabolites, using an elastic net regularized regression model that accurately estimates chronological age. Notably, we observed significant chronological disparities among the healthy population, APL patients, and CRC patients. By combining the analysis of circulative carcinoembryonic antigen levels with the categorization of individuals into the "hypo" metabolic aging subgroup, our blood test demonstrates the ability to detect APL and CRC with positive predictive values of 68.4% (64.3%, 72.2%) and 21.4% (17.8%, 25.9%), respectively. Conclusions: This innovative approach utilizing our metabolic aging clock holds significant promise for accurately assessing biological age and enhancing our capacity to detect APL and CRC.

The Diagnostic Accuracy of a Fecal Immunochemical Test in Detecting Colorectal Cancer and Advanced Precancerous Colorectal Neoplasia in Patients with Iron Deficiency: A Protocol for Systematic Review and Meta-Analysis.

Background. Iron deficiency (ID) is a common micronutrient deficiency and the leading cause of anemia worldwide. ID can be caused by chronic occult blood loss from colorectal neoplasia including colorectal cancer (CRC) and advanced precancerous colorectal lesions. Current guidelines recommend colonoscopy in both men and postmenopausal women presenting with ID anemia (IDA). However, there is controversy on the investigation of patients presenting with a lower risk of CRC including younger women with ID and those with nonanemic ID (NAID). There is a need for a triaging tool to identify which ID patients may benefit from colonoscopy. The fecal immunochemical test (FIT) is sensitive for CRC screening in an asymptomatic population, but its role in ID patients is unclear. The aim of this study is to conduct a systematic review to determine the diagnostic accuracy of FIT for detecting CRC and advanced precancerous neoplasia in individuals presenting with ID with or without anemia. Methods and Analysis. This protocol conforms with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols and Cochrane Handbook for Systematic Reviews of Diagnostic Test Accuracy. A comprehensive search of the MEDLINE, Embase, and Web of Science databases will be undertaken for studies published after 2010 which involve patients with ID, who completed a FIT in the 6 months prior to colonoscopy, with FIT sensitivity and specificity calculated against the reference standard colonoscopy. The search will be limited to studies conducted after 2010 to reduce variability in colonoscopy quality. Risk of bias assessment will be conducted using the Quality Assessment of Diagnostic Accuracy Studies version 2. FIT sensitivity and specificity will be the primary measure of diagnostic accuracy, and data will be analysed using a random effects meta-analysis. Discussion. This review and meta-analysis will be the first to systematically explore the value of the FIT as a triaging tool for patients with ID. This trial is registered with CRD42022367162.

High accuracy of a blood ctDNA-based multimodal test to detect colorectal cancer

Detection of circulating tumor DNA (ctDNA) is a minimally invasive and convenient blood-based screening strategy that may increase effectiveness of colorectal cancer (CRC) screening. A novel multimodal ctDNA-based blood assay that integrates genomics, epigenomics and fragmentomics, as well as proteomics in a refined version, was tested in blood samples from two cohorts: (i) consecutive fecal immunochemical test (FIT)-positive individuals from the CRC Barcelona stool-based screening program; (ii) patients diagnosed with CRC. Primary endpoint was the performance of the test to detect CRC at different tumor-node-metastasis (TNM) stages. Secondary endpoint was the ability of the test to detect advanced precancerous lesions (advanced adenoma or advanced serrated lesion). A total of 623 blood samples were analyzed in the primary analysis. Sensitivity and specificity of the assay to detect CRC was 93% and 90%, respectively. The sensitivity of CRC detection according to TNM stages was 84% for stage I, 94% for stage II and 96% for stage III (70/73) (P< 0.024). Sensitivity to detect advanced precancerous lesions was 23% with a refined version of the test (including protein and updating bioinformatic thresholding). A blood-based multimodal ctDNA assay detected CRC with high accuracy. This minimally invasive, accessible and convenient assay may help to increase the effectiveness of CRC screening.

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

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

Metabolite Alterations and Interactions with Microbiota in Helicobacter pylori-Associated Gastric Lesions.

Metabolites and their interactions with microbiota may be involved in Helicobacter pylori-associated gastric lesion development. This study aimed to explore metabolite alterations upon H. pylori eradication and possible roles of microbiota-metabolite interactions in progression of precancerous lesions. Targeted metabolomics assays and 16S rRNA gene sequencing were conducted to investigate metabolic and microbial alterations of paired gastric biopsy specimens in 58 subjects with successful and 57 subjects with failed anti-H. pylori treatment. Integrative analyses were performed by combining the metabolomics and microbiome profiles from the same intervention participants. A total of 81 metabolites were significantly altered after successful eradication compared to failed treatment, including acylcarnitines, ceramides, triacylglycerol, cholesterol esters, fatty acid, sphingolipids, glycerophospholipids, and glycosylceramides, with P values of <0.05 for all. The differential metabolites showed significant correlations with microbiota in baseline biopsy specimens, such as negative correlations between Helicobacter and glycerophospholipids, glycosylceramide, and triacylglycerol (P < 0.05 for all), which were altered by eradication. The characteristic negative correlations between glycosylceramides and Fusobacterium, Streptococcus, and Gemella in H. pylori-positive baseline biopsy specimens were further noticed in active gastritis and intestinal metaplasia (P < 0.05 for all). A panel including differential metabolites, genera, and their interactions may help to discriminate high-risk subjects who progressed from mild to advanced precancerous lesions in short-term and long-term follow-up periods with areas under the curve (AUC) of 0.914 and 0.801, respectively. Therefore, our findings provide new insights into the metabolites and microbiota interactions in H. pylori-associated gastric lesion progression. IMPORTANCE In this study, a panel was established including differential metabolites, genera, and their interactions, which may help to discriminate high-risk subjects for progression from mild lesions to advanced precancerous lesions in short-term and long-term follow-up.

Associations of the 2018 World Cancer Research Fund/American Institute of Cancer Research (WCRF/AICR) cancer prevention recommendations with stages of colorectal carcinogenesis.

While adherence to cancer prevention recommendations is linked to lower risk of colorectal cancer (CRC), few have studied associations across the entire spectrum of colorectal carcinogenesis. Here, we studied the relationship of the standardized 2018 World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) Score for cancer prevention recommendations with detection of colorectal lesions in a screening setting. As a secondary objective, we examined to what extent the recommendations were being followed in an external cohort of CRC patients. Adherence to the seven-point 2018 WCRF/AICR Score was measured in screening participants receiving a positive fecal immunochemical test and in CRC patients participating in an intervention study. Dietary intake, body fatness and physical activity were assessed using self-administered questionnaires. Multinomial logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for screen-detected lesions. Of 1486 screening participants, 548 were free from adenomas, 524 had non-advanced adenomas, 349 had advanced lesions and 65 had CRC. Adherence to the 2018 WCRF/AICR Score was inversely associated with advanced lesions; OR 0.82 (95% CI 0.71, 0.94) per score point, but not with CRC. Of the seven individual components included in the score, alcohol, and BMI seemed to be the most influential. Of the 430 CRC patients included in the external cohort, the greatest potential for lifestyle improvement was seen for the recommendations concerning alcohol and red and processed meat, where 10% and 2% fully adhered, respectively. Adherence to the 2018 WCRF/AICR Score was associated with lower probability of screen-detected advanced precancerous lesions, but not CRC. Although some components of the score seemed to be more influential than others (i.e., alcohol and BMI), taking a holistic approach to cancer prevention is likely the best way to prevent the occurrence of precancerous colorectal lesions.

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

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 hemoglobin component (mt-sDNA Hgb-) in patients with IBD, while measuring sensitivity for colorectal cancer and advanced colorectal neoplasia (ACRN). This was a multi-center, proof-of-concept investigation in persons aged 18-84 years with a diagnosis of IBD, or primary sclerosing cholangitis (PSC) with IBD. Enrollment occurred between March 2013-May 2016. Stool was tested with the mt-sDNA molecular markers only, minus the immunochemical hemoglobin component. The analysis set contained 355 samples. The median age was 52 (range 39-62) years, 45.6% female, 93% 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), non-advanced precancerous lesions in 7.6% (N=27), and three-fourths (74.7%, N=265) had negative findings. Mt-sDNA Hgb- sensitivity was 73.3% for any stage cancers, and 76.2% for ACRN. Sensitivity was highest for IBD-associated HGD at 100% and 84.6% for IBD-associated LGD ≥ 1cm. 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-sDNA Hgb- test score (p=0.028) amongst neoplasia-negative individuals, but not in patients with ACRN. These data highlight the potential of multitarget stool-DNA marker testing as an important addition to colorectal cancer surveillance by complementing colonoscopic evaluations in inflammatory bowel disease patients.

S2246 FIT or Unfit: Advanced Colon Cancer Screening

Introduction: Colorectal cancer (CRC) is the third leading cause of cancer related mortality worldwide. The U.S. Preventative Services Task Force guidelines recommend screening for average risk patients at age 45, and modalities include stool-based or direct visualization tests. We report a presentation of Stage IV colorectal adenocarcinoma in the setting of 3 annual negative fecal immunochemical testing (FIT) tests. Case Description/Methods: A 67-year-old woman presented with shortness of breath, unintentional weight loss, and abdominal pain. She denied hematochezia or melena. Physical exam was notable for pallor and right upper quadrant pain. Initial laboratory data showed normocytic anemia with a hemoglobin 10.1 g/dL, alkaline phosphatase 610 U/L, aspartate aminotransaminase 116 U/L, alanine aminotransaminase 67 U/L. Computed tomography of the chest, abdomen, and pelvis revealed a normal colon and extensive metastatic disease in the liver and lungs with bilateral subsegmental pulmonary emboli. Chart review was notable for negative FIT tests in 2017, 2018, and 2020, performed within a year of this presentation. Further workup was significant for elevated carcinogenic embryonic antigen 1470 ng/mL, and normal alpha-fetoprotein and cancer antigen 19-9 levels. Colonoscopy revealed an infiltrating, ulcerated, semi-circumferential mass at the ileo-cecal valve and ascending colon (Figure). Pathology demonstrated moderately differentiated invasive colonic adenocarcinoma with malignant glands infiltrating a desmoplastic stroma. Immunohistochemistry did not show any microsatellite instability changes. Discussion: One study showed FIT testing was 73.8% sensitive for detecting Stage I-III CRC, however, sensitivities dropped with advanced precancerous lesions and sessile serrated polyps to 23.8% and 5.1% respectively. Another retrospective cohort looking at 6 consecutive rounds of FIT testing demonstrated lower accuracy of detecting proximal colon cancers compared to distal cancers (0.45 vs 0.73; P< 0.001). Lower cut off values of qualitative FIT correlated with better sensitivities, however, specificity declined. Although FIT testing is able to detect the majority of colorectal cancers, it has decreased accuracy and sensitivity in advanced precancerous lesions, sessile serrated polyps, and proximal (right) colon lesions. Colonoscopy is considered gold standard and further guidelines should recommend a standardized cut off value to help improve screening efficacy.Figure 1.: Large fungating mass in the ascending colon and ileo-cecal valve.

Comparison of Colonoscopy, Fecal Immunochemical Test, and Risk-Adapted Approach in a Colorectal Cancer Screening Trial (TARGET-C)

The screening yield and related cost of a risk-adapted screening approach compared with established screening strategies in population-based colorectal cancer (CRC) screening are not clear. We randomly allocated 19,373 participants into 1 of the 3 screening arms in a 1:2:2 ratio: (1) one-time colonoscopy (n= 3883); (2) annual fecal immunochemical test (FIT) (n= 7793); (3) annual risk-adapted screening (n= 7697), in which, based on the risk-stratification score, high-risk participants were referred for colonoscopy and low-risk ones were referred for FIT. Three consecutive screening rounds were conducted for both the FIT and the risk-adapted screening arms. Follow-up to trace the health outcome for all the participants was conducted over the 3-year study period. The detection rate of advanced colorectal neoplasia (CRC and advanced precancerous lesions) was the main outcome. The trial was registered in the Chinese Clinical Trial Registry (number: ChiCTR1800015506). In the colonoscopy, FIT, and risk-adapted screening arms over 3 screening rounds, the participation rates were 42.4%, 99.3%, and 89.2%, respectively; the detection rates for advanced neoplasm (intention-to-treat analysis) were 2.76%, 2.17%, and 2.35%, respectively, with an oddsratio (OR)colonoscopy vs FIT of 1.27 (95% confidence interval [CI]: 0.99-1.63; P= .056), an ORcolonoscopy vsrisk-adapted screening of 1.17 (95% CI, 0.91-1.49; P= .218), and an ORrisk-adapted screeningvs FIT of 1.09 (95% CI, 0.88-1.35; P= .438); the numbers of colonoscopies needed to detect 1 advanced neoplasm were 15.4, 7.8, and 10.2, respectively; the costs for detecting 1 advanced neoplasm from a government perspective using package payment format were 6928 Chinese Yuan (CNY) ($1004), 5821 CNY ($844), and 6694 CNY ($970), respectively. The risk-adapted approach is a feasible and cost-favorable strategy for population-based CRC screening and therefore could complement the well-established one-time colonoscopy and annual repeated FIT screening strategies. (Chinese Clinical Trial Registry; ChiCTR1800015506).

Accuracy of blood-based biomarkers for screening precancerous colorectal lesions: a protocol for systematic review and meta-analysis

IntroductionColorectal cancer (CRC) is the third most diagnosed cancer and the second most common cause of cancer mortality worldwide. Most CRCs develop through either the adenoma-to-carcinoma or the serrated pathways,...