Fecal Immunochemical Test Research Articles

Varying faecal immunochemical test positivity thresholds impacts colorectal cancer detection

Abstract Background Colorectal cancer (CRC) is screened for by the faecal immunochemical test (FIT) in Ireland. The FIT positivity threshold in Ireland is 45 micrograms (µg) of haemoglobin per gram (g) of stool. FIT positivity thresholds influence both demand for screening colonoscopies and CRC detection rates through screening. This study aimed to assess the impact of varying FIT positivity thresholds on CRC detection rates through screening in Ireland. Methods This study used data from BowelScreen - The National Bowel Screening Programme, to retrospectively assess the impact of altering the FIT positivity threshold, adjusting it to correspond with neighbouring European countries, on CRC detection rates through screening in Ireland between 2013 and 2021. All analyses were conducted on Stata 17. Results 1,552 individuals were diagnosed with CRC in Ireland after a positive FIT performed through BowelScreen between 2013-2021. Adopting the same FIT positivity thresholds as the Netherlands (47µg/g), Scotland (80µg/g), England (120µg/g) and Wales (150µg/g) would have resulted in 21 (1.4%), 262 (17.1%), 458 (29.8%) and 556 (36.2%) fewer diagnoses of CRC through BowelScreen during this period, respectively. Additionally, increasing the positivity threshold to correspond with these countries would have resulted in between 1.7-41.9% fewer stage 1, between 1.0-30.9% fewer stage 2, between 1.4-32.9% fewer stage 3 and between 0-5.6% fewer stage 4 CRCs detected. Conclusions Changing the FIT positivity threshold in Ireland to correspond with that of other neighbouring European countries would have reduced the detection of CRC through screening to varying degrees. The detection of stage 1 CRCs would have been most greatly reduced, but up to almost a third of all stage 2 and stage 3 CRCs would not have been detected if some alternative, higher positivity thresholds were adopted. Key messages • Increasing the FIT positivity threshold in Ireland will need careful consideration to keep the optimum positive predictive value of a colonoscopy. • Lower stage 1-3 CRC detection rates may occur as a result.

Management of pT1 CRC detected on the colorectal cancer screening programme (Basque Country. Spain)

Abstract Background The Bowel Cancer Screening Programme (BCSP) started in 2009 with faecal immunochemical test (FIT, with cut-off 20µg/g faeces) every 2 years (for 50-69 year- olds). 2.518.715 people were invited until 2021. Participation rate was 70.4% with 5.3% positive rate and 92.7% adherence to colonoscopy. Colorectal cancer (CRC) detection rate was 2.28 ‰ with 70.6% found in initial stage. The PT1 (stage I) represented 40% of the total cancer detected (4,050 in the overall period). Objectives To compare the characteristics and management of pT1 CRC. Methods Retrospective cohort study including pT1 CRC Stage I diagnosed after colonoscopy in positive FIT from 2009-2017. Variables: sex, age groups, endoscopic and surgical treatment, CRC recurrence and survival. Chi-square, Logistic Regression, SPSS v.23. Results Of the 1,523 CRC detected, 585 were detected as pT1 and I stage (38.4%). 73.4% in men and by age group 59% over 60 years-old. 48.5% were treated with surgery and 51.5% with endoscopic resection. No significant differences were found adjusted by sex and age regardless of treatment. In 57.6% of patients under surgery, CRC was not reported by pathological analysis. All cases followed up by colonoscopy with variability in the number of surveillances over time. 4.1% (24) had CRC recurrence with 87% detected in the surveillance, no significant differences regardless of the treatment. 1.5% (9) died due to CRC progression. Conclusions Apart from the high number of CRC detected in early stages by the screening Programme, an important number of cases are reported as pT1 CRC. Endoscopic resection is one of the treatments of choice without significant impact either in recurrence of neoplasia or mortality. However, surgical procedure shows overtreatment because of the high number of cases without CRC after the procedure. Therefore, endoscopic resection could be the main choice to treat pT1 CRC. Key messages • Endoscopic resection is one of the treatment of choice without impact in recurrence for the pT1 CRC detected through the BCSP. • The Basque BCSP obtains excellent participation rate, reflected in early detection and treatment of pre and malignant lesions.

Multitarget Stool RNA Test for Colorectal Cancer Screening

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. To evaluate the sensitivity and specificity of a noninvasive, multitarget stool RNA (mt-sRNA) test (ColoSense) test compared with results from a colonoscopy. 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. 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. 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. 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. ClinicalTrials.gov Identifier: NCT04739722.

Risk factors for colorectal cancer in a fecal immunochemical test-positive group: The National Health Insurance Service-National Health Screening Cohort.

Colorectal cancer (CRC) was the fourth most common cancer in Republic of Korea in 2019. It has a gradually increasing mortality rate, indicating the importance of screening for CRC. Among the various CRC screening test, fecal immunochemical test (FIT) is a simple yet most commonly used. Neverthelss, there have been only few long-term studies on subjects with FIT-positive. Therefore, in this study, we aimed to investigate the risk factors for CRC in FIT-positive patients using the National Health Insurance Service Bigdata database. Among 1737633 individuals with a FIT screening result for CRC in 2009, 101143 (5.82%) were confirmed to be FIT positive. The CRC incidence over 10years (up to 2018) of these participants was investigated using the National Cancer Registry. Out of the 101143 FIT-positive participants, 4395 (4.35%) were diagnosed with CRC. The FIT-positive patients who underwent a second round of screening showed a 5-year cumulative CRC incidence of approximately 1.25%, whereas those who did not showed an incidence of approximately 3.75%. Among the FIT-positive patients, the CRC incidence in the non-compliance group for the second round of screening was 2.8 times higher than that in the compliance group. In FIT-positive participants, non-compliance with the second round of screening was identified as a major risk factor for CRC development. It is necessary to establish appropriate strategies for managing risk factors for CRC in FIT-positive patients to increase the rate of compliance with the second round of CRC screening.

The use of non-invasive stool tests for verification of Helicobacter pylori eradication and clarithromycin resistance.

Clarithromycin resistance of Helicobacter pylori (H. pylori) represents a major challenge in eradication therapy. In this study, we assessed if non-invasive stool tests can be used to verify successful H. pylori eradication and determine clarithromycin resistance. In this prospective study, patients undergoing urea breath testing (UBT) for confirmation of H. pylori eradication were asked to collect the stool as both a dry fecal sample and fecal immunochemical test (FIT). Stool H. pylori antigen testing (SAT) was performed on these samples and assessed for its accuracy in eradication verification. Type and duration of antibiotic treatment were retrospectively collected from patient records and compared with clarithromycin resistance determined by PCR of stool samples. H. pylori eradication information was available for a total of 145 patients (42.7% male, median age: 51.2). Successful eradication was achieved in 68.1% of patients. SAT on FIT samples had similar accuracy for eradication assessment compared to dry fecal samples, 72.1% [95% CI 61.4-81.2] versus 72.2% [95% CI 60.9-81.7]. Clarithromycin resistance rate was 13.4%. H. pylori antigen testing on FIT stool samples to verify H. pylori eradication is feasible and has similar accuracy as H. pylori antigen testing on dry stool samples. Dry stool, but not FIT, was suitable for non-invasive identification of H. pylori clarithromycin resistance by rt-PCR personalizing antibiotic treatment strategies without the need for invasive diagnostics is desirable, as the cure rate of first-line empirical H. pylori treatment remains low.

Feasibility and acceptability of motivational interviewing to promote colorectal cancer screening among average risk Chinese older adults

ObjectiveThis study aims to evaluate the feasibility and acceptability of motivational interviewing to promote fecal immunochemical test (FIT) uptake among average-risk Chinese older adults and to preliminarily examine its effects on the knowledge level, perceived barriers to and benefits of the FIT, self-efficacy in screening, screening intention and FIT uptake. MethodsA one-group pre-test and post-test study design was adopted. A motivational interviewing intervention using face-to-face and telephone approaches was delivered to average-risk Chinese older adults aged 50–75 years. The number of participants approached, the number eligible for participation and intervention completion, and study retention rates were recorded. The knowledge, perceived benefits of, barriers to, self-efficacy in and intention to participate in colorectal cancer (CRC) screening were assessed before and after the intervention. FIT uptake was recorded 3 months after the intervention. Interviews were conducted to record the participants’ experiences of participating in the intervention. ResultsTwenty Chinese older adults completed the study. The motivational interviewing intervention improved the screening intention, knowledge of CRC and its screening, the perceived benefits of and self-efficacy in screening and perceived barriers to screening. Twelve participants (60.0%) had undergone FIT screening. Nineteen participants attended the interviews. They were all satisfied with the intervention. Three categories were generated regarding their experience in participating in the intervention, namely, (1) enhanced motivation and self-efficacy in screening, (2) enhanced understanding of the CRC screening program, and (3) areas for intervention improvement. ConclusionsThe implementation of a motivational interviewing intervention was feasible and was acceptable to average-risk Chinese older adults. A full-scale study should be conducted in the future. Trial registrationISRCTN39658070.

Impact of a Time-Related Benchmark on the Adenoma Detection Rate in Surveillance Colonoscopy: A STROBE Statement-Oriented Cross-Sectional Cohort Study.

Colorectal adenomas are precursor lesions of globally increasing colorectal cancer. Hence, a high adenoma detection rate in colonoscopy is pivotal. We investigated the clinical impact of stratified colonoscopy observation time combined with observation time/intubation time ratio on the detection of colorectal adenomas. We conducted a single-center retrospective study including 369 consecutive patients who underwent colonoscopy following fecal immunochemical tests between May 2021 and April 2022. The primary outcome measure was the impact of the stratified observation time and observation time/ intubation time ratio (category 1: <6.0 minutes and <1.0, category 2: <6.0 minutes and ≥1.0, category 3: ≥6.0 minutes and <1.0, and category 4: ≥6.0 minutes and ≥1.0) on adenoma detection rate. Cecum intubation was obtained in 367 patients (99.5%). Adenomas were detected in 226 patients (61.2%). From the univariate analysis, age ≥53 years, habitual alcohol intake, colonoscopy attachment (+), and observation time with observation time/intubation time ratio categories 3 and 4 were determined as significant factors for adenoma detection rate. From the logistic regression analysis, age ≥ 53 years (odds ratio: 4.86, 95% CI: 2.25-10.52), habitual alcohol intake (odds ratio: 2.26, 95% CI: 1.33-3.82), category 3 (odds ratio: 3.66, 95% CI: 1.81-7.45), and category 4 (odds ratio: 5.60, 95% CI: 2.92-10.73) were significant factors for adenoma detection rate. We propose the observation time with observation time/intubation time ratio combined benchmark (with categories' thresholds based on observation time >6 minutes and scope withdrawal time exceeding intubation time [observation time/intubation time ratio > 1]) as a novel colonoscopy quality indicator. These findings represent an important educational message for endoscopists.

Effect of aspirin, warfarin, and proton-pump inhibitors on performance of fecal immunochemical test in colorectal cancer screening: a systematic review and meta-analysis.

This study aims to investigate the impact of antithrombotic agents and proton-pump inhibitors (PPIs) on fecal immunochemical test (FIT). PubMed, EMBASE, Web of Science, Cochrane Central, and Google Scholar were searched from inception until September 3, 2023. Studies comparing the diagnostic performance of FIT between medicine users and non-users in average-risk colorectal cancer screening populations were included. Pooled sensitivity, specificity, and positive predictive values (PPVs) for advanced neoplasia (AN) of FIT were compared by reporting pooled odds ratios (ORs) with 95% confidence intervals (CIs) using a random-effects model. Twenty-two studies enrolling 5,572,367 individuals were included. For aspirin, pooled sensitivity and specificity for AN were 57.2% and 88.4% in users versus 60.2% and 93.2% in non-users; while pooled ORs were 1.49 (95% CI 0.89-2.48, P = 0.13) and 0.72 (95% CI 0.62-0.83, P < 0.001), respectively. In subgroup analysis, there was no difference in sensitivity and specificity between the two groups at the cutoff of 20μg Hb/g (P = 0.57 and 0.29, respectively) but a significantly lower specificity in users compared with non-users at lower cutoffs (P < 0.001). Moreover, a significantly lower PPVAN in users compared with non-users was observed after matching age and sex confounders (P = 0.001). Warfarin had no significant influence on PPVAN of FIT (P = 0.43). PPIs were associated with a significantly lower PPVAN in users (P < 0.001). Aspirin use was associated with lower specificity and PPV of FIT. Aspirin discontinuation before FIT to reduce false-positive results should be interpreted with caution given concerns about cardiovascular events. Increasing cutoff values of FIT in aspirin users may be another possible approach. Additionally, warfarin withdrawal before FIT is unnecessary but PPIs withdrawal before FIT is recommended to reduce false-positive results.

Effect of multiple loading FIT sample collection devices on faecal haemoglobin concentration.

Faecal immunochemical tests (FIT) are routinely used in colorectal cancer (CRC) screening programmes around the world. More recently, quantitative FIT has been recommended to help triage patients presenting to primary care with symptoms suggestive of CRC. Participants collect faecal samples using sampling probes which are inserted into sample collection devices (SCDs) containing preservative buffer. The SCDs have an internal collar designed to remove excess sample. The aim of this study was to investigate the impact of multiple loading on faecal haemoglobin concentration (f-Hb) using SCDs of four FIT systems. Pools of f-Hb negative samples were spiked with blood, homogenised and loaded into SCDs 1, 3 and 5 times, with insertion of the sampling probes into the SCDs with and without mixing between loads. The f-Hb was measured using the relevant FIT system. The percentage change in f-Hb for multiple loads was compared with a single load for each system for the mixed and unmixed groups. The p values show a significant difference (p < 0.05) in the mass and f-Hb for the mixed and unmixed group, for 1-3 and 1-5 loads for all systems. The median percentage change in f-Hb for the mixed is higher than the unmixed group. This study showed that multiple loading does significantly increase the f-Hb in the SCDs.

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.

Hub-and-Spoke centralized intervention to optimize colorectal cancer screening and follow-up: A pragmatic, cluster-randomized controlled trial protocol

BackgroundGuidelines recommend screening for colorectal cancer (CRC), but participation and abnormal test follow up rates are suboptimal, with disparities by demography. Evidence-based interventions exist to promote screening, but community adoption and implementation are limited. MethodsThe San Diego Accelerating Colorectal Cancer Screening and Follow-up through Implementation Science (ACCSIS) program is an academic-community partnership testing regional implementation of a Hub-and-Spoke model for increasing CRC screening and follow-up. The “hub” is a non-academic, non-profit organization that includes 17 community health center (CHC) systems, serving over 190 rural and urban clinic sites. The “spokes” are 3 CHC systems that oversee 11–28 clinics each, totaling over 60 clinics. Using a cluster-randomized trial design, 9 clinics were randomized to intervention and 16 to usual care. Within intervention clinics, approximately 5000 eligible patients not up-to-date with CRC screening per year were identified for intervention. Interventions include an invitation primer, a mailed fecal immunochemical test with completion instructions, and phone and text-based reminders (hub) and patient navigation protocol to promote colonoscopy completion after abnormal FIT (spoke). Outcomes include: 1) proportion of patients up-to-date with screening after three years in intervention versus non-intervention clinics; 2) proportion of patients with abnormal FIT completing colonoscopy within six months of the abnormal result. Implementation science measures are collected to assess acceptability, intervention and usual care adaptations, and sustainability of the intervention strategies. ConclusionThis large-scale, regional cluster randomized trial among CHCs serving diverse populations is anticipated to accelerate progress in CRC prevention in underserved populations.Trial registration: NCT04941300

Interval post-colonoscopy colorectal cancer following a negative colonoscopy in a fecal immunochemical test-based screening program.

In the Dutch colorectal (CRC) screening program, fecal immunochemical test (FIT)-positive individuals are referred for colonoscopy. If no relevant findings are detected at colonoscopy, individuals are reinvited for FIT screening after 10 years. We aimed to assess CRC risk after a negative colonoscopy in FIT-positive individuals. In this cross-sectional cohort study, data were extracted from the Dutch national screening information system. Participants with a positive FIT followed by a negative colonoscopy between 2014 and 2018 were included. A negative colonoscopy was defined as a colonoscopy during which no more than one nonvillous, nonproximal adenoma < 10 mm or serrated polyp < 10 mm was found. The main outcome was interval post-colonoscopy CRC (iPCCRC) risk. iPCCRC risk was reviewed against the risk of interval CRC after a negative FIT (FIT IC) with a 2-year screening interval. 35 052 FIT-positive participants had a negative colonoscopy and 24 iPCCRCs were diagnosed, resulting in an iPCCRC risk of 6.85 (95 %CI 4.60-10.19) per 10 000 individuals after a median follow-up of 1.4 years. After 2.5 years of follow-up, age-adjusted iPCCRC risk was approximately equal to FIT IC risk at 2 years. Risk of iPCCRC within a FIT-based CRC screening program was low during the first years after colonos-copy but, after 2.5 years, was the same as the risk in FIT-negative individuals at 2 years, when they are reinvited for screening. Colonoscopy quality may therefore require further improvement and FIT screening interval may need to be reduced after negative colonoscopy.

Impact of the COVID-19 Pandemic on the Diagnosis of Colorectal Cancer within a Population-Based Organized Screening Program.

The interruption of the activity of population-based organized colorectal cancer (CRC) screening programs due to the COVID pandemic may have affected their results in terms of the detection of preneoplastic lesions and CRC. We evaluated the impact of the COVID pandemic on the delays, participation, adherence to colonoscopies, lesions detected, and CRC stage at diagnosis in a CRC screening program. We analyzed all the invitations between 1 January 2019 and 31 December 2021. We defined the pandemic period as the period after 12 March 2020. We calculated the delay intervals (successive and all rounds), the rates of participation, adherence to colonoscopy after a positive fecal immunochemical test (FIT), and the diagnostic yield of colonoscopy, specifically of CRC and colorectal neoplasia (CRC and/or adenoma), as well as the CRC stage at diagnosis. In the period analyzed, 976,187 invitations were sent (61.0% in the pandemic period), 439,687 FIT were returned (62.4% in the pandemic period) and 23,092 colonoscopies were performed (59.1% in the pandemic period). The colonoscopies were normal in 7378 subjects (32.4%) and CRC was detected in 916 subjects (4.0%). In successive rounds, the delay increased significantly by seven months during the pandemic period (p < 0.001). In all the invitations, the delay from the invitation to the colonoscopy increased significantly by 8 days (p < 0.001). Once adjusted for the confounding variables, the participation in the screening program increased significantly (OR = 1.1; 95% CI = 1.09-1.11), with no changes in the adherence to colonoscopy (OR = 0.9; 95% CI = 0.8-1.0). We found no differences in the diagnostic yield of colonoscopy in terms of CRC (OR = 0.90; 95% CI = 0.78-1.02) or colorectal neoplasia (OR = 0.98; 95% CI = 0.92-1.03) detection. Finally, we found no differences in the CRC stage at diagnosis (p = 0.2). Although the interruption of the CRC screening program due to the COVID pandemic increased the delays, it did not reduce participation, adherence to colonoscopy, or the diagnostic yield of colonoscopy.

Serum methylation of GALNT9, UPF3A, WARS, and LDB2 as noninvasive biomarkers for the early detection of colorectal cancer and advanced adenomas

BackgroundEarly detection has proven to be the most effective strategy to reduce the incidence and mortality of colorectal cancer (CRC). Nevertheless, most current screening programs suffer from low participation rates. A blood test may improve both the adherence to screening and the selection to colonoscopy. In this study, we conducted a serum-based discovery and validation of cfDNA methylation biomarkers for CRC screening in a multicenter cohort of 433 serum samples including healthy controls, benign pathologies, advanced adenomas (AA), and CRC.ResultsFirst, we performed an epigenome-wide methylation analysis with the MethylationEPIC array using a sample pooling approach, followed by a robust prioritization of candidate biomarkers for the detection of advanced neoplasia (AN: AA and CRC). Then, candidate biomarkers were validated by pyrosequencing in independent individual cfDNA samples. We report GALNT9, UPF3A, WARS, and LDB2 as new noninvasive biomarkers for the early detection of AN. The combination of GALNT9/UPF3A by logistic regression discriminated AN with 78.8% sensitivity and 100% specificity, outperforming the commonly used fecal immunochemical test and the methylated SEPT9 blood test.ConclusionsOverall, this study highlights the utility of cfDNA methylation for CRC screening. Our results suggest that the combination methylated GALNT9/UPF3A has the potential to serve as a highly specific and sensitive blood-based test for screening and early detection of CRC.

Screening History and 7-Year Survival in 32,099 Colorectal Cancer Patients: A Population-Based Cohort Study.

It is unclear whether colorectal cancer screening history, regardless of stage, is an independent predictor of survival, and if the screening advantage persists after diagnosis. 32 099 patients with colorectal cancer were enrolled in this population-based cohort study. We used data from the Taiwan Cancer Registry on patients with a first-time diagnosis of colorectal cancer between 2013 and 2015. In addition, we utilized data from a nationwide database of colorectal cancer screening programs to evaluate patients' screening histories, and sourced outcome data from the National Death Registry, tracking patients up to the last day of 2019. Compared with fecal immunochemical testing (FIT)-positive patients with a follow-up examination, the adjusted hazard ratios (95% confidence intervals) for death from colorectal cancer were 1.40 (1.26-1.56) for FIT-positive patients without a follow-up examination, 1.63 (1.48-1.78) for FIT-negative patients, and 1.76 (1.65-1.89) for never screened patients. The adjusted hazard ratios for the FIT-positive patients with a follow-up examination increased when diagnosis was delayed by more than 12 months and were 1.2 after a 2-year delay. The adjusted hazard ratios for FIT-negative patients were approximately 2.0, decreased rapidly to 1.6, and stabilized after the 9th time-to-diagnosis month. In colorectal cancer patients, screening history prior to diagnosis is an independent prognostic factor, regardless of cancer stage or other variables. This study recommends that physicians take screening history into account during diagnosis to optimize follow-up and management for patients at higher risk.

Colorectal cancer screening-what does the recent NordICC trial mean for the U.S. population?

The incidence of colorectal cancer (CRC) has declined over time, though it remains a significant cause of morbidity and mortality in the U.S. It has the third highest incidence in incidence among all cancers and is the second leading cause of cancer death in both men and women. Screening reduces the incidence and mortality from CRC. There are several modalities for CRC screening, but the most common ones are a choice between a non-invasive stool-based test, such as fecal immunochemical testing (FIT) or an invasive endoscopic modality, such as colonoscopy. In the U.S. colonoscopy is the predominant CRC screening modality, with observational studies reporting large reductions in CRC incidence and mortality. Recently, a large randomized controlled trial (RCT) on effectiveness of colonoscopy reported smaller than expected reduction in CRC incidence and no reduction in CRC mortality with colonoscopy screening. Explanations of the lower than expected benefit include low uptake of colonoscopy, short follow-up for mortality endpoints and quality indicators (QIs) for some of the endoscopists participating in the screening colonoscopies. The findings of the study need to be taken in context with other literature on effectiveness of colonoscopy, with the overall message of reassuring patients of the benefits of screening, and colonoscopy. Here, we discuss the latest evidence on colonoscopy screening and it in the context of other screening modalities and the landscape.

Canadian Landscape Assessment of Colorectal Cancer Screening during the COVID-19 Pandemic.

The COVID-19 pandemic caused disruptions in colorectal cancer (CRC) care by interrupting CRC screening across Canada, posing problems for program participants, patients, and physicians and no clear understanding of how provincial healthcare systems would adapt in the face of another pandemic or shock to the system. A nationwide online survey targeted to members of the National Colorectal Cancer Screening Network (NCCSN) using the SurveyMonkey platform was conducted to gain insight into the impact of the pandemic on CRC screening from March 2020 to March 2022 across all thirteen Canadian jurisdictions. The survey included 25 multiple-choice and free-text questions. Both quantitative and qualitative methods were used to analyze the data using Microsoft Excel and NVivo software. Twenty-one provincial and territorial representatives participated in the survey conducted between 13 May 2022 and 27 October 2022. All jurisdictions (100%) reported decreased screenings, including fecal immunochemical testing (FIT) or Fecal Occult Blood testing (FOBT) procedures, and subsequent diagnostic colonoscopies. The average wait time for colonoscopies due to a positive FIT/FOBT was 76 days. To mitigate the backlog and initiate an effective intervention plan, representatives highlighted some key points, including the importance of prioritizing high-risk patients. Survey results concluded that the COVID-19 pandemic impacted CRC screening across Canada. This landscape assessment can help inform intervention measures and policy-related solutions to create greater resilience for CRC screening in provincial and territorial healthcare systems.

S435 Cost-Effectiveness of Mt-sDNA vs Fecal Immunochemical Test for Colorectal Cancer Screening in a Medicare Population

S435 Cost-Effectiveness of Mt-sDNA vs Fecal Immunochemical Test for Colorectal Cancer Screening in a Medicare Population

S450 Impact of Patient Navigator to Improve Completion of Fecal Immunochemical Testing in Primary Care: Patient’s Profile Perspective

S450 Impact of Patient Navigator to Improve Completion of Fecal Immunochemical Testing in Primary Care: Patient’s Profile Perspective

S436 Increased Incidence of Advanced Adenoma After a Positive Fecal Immunochemical Test in Low-Income Uninsured Patients

S436 Increased Incidence of Advanced Adenoma After a Positive Fecal Immunochemical Test in Low-Income Uninsured Patients