Immunochemical Fecal Occult Blood Test Research Articles

Colonic diverticulosis as an isolated colonoscopy finding for iFOBT-positive patients

Colonic diverticular disease is a common medical condition throughout the world. It is one of the most common findings during the endoscopic evaluation of the colon, such as colonoscopy. A retrospective cohort single-centre study was carried out for all patients referred for colonoscopy with positive immunochemical faecal occult blood test (iFOBT) results in 2016-2018, mostly within The National Bower Cancer Screening Program (NBCSP) in QLD, Australia. The cohort of 319 patients were isolated from all iFOBT-positive individuals with such finding as a diverticular disease. Colonic diverticulosis affected the patients above 43 years old with positive iFOBT, more males than females in this study. In most cases, colonoscopy consisted of benign findings, and diverticular disease was revealed in 47.7% of the patients with such indication for colonoscopy as positive iFOBT. 28.8% of the patients were diagnosed with colonic diverticulosis only. The sigmoid colon was affected by diverticulosis in 96.2% of the cases. Overall, the colorectal cancer (CRC) diagnosis rate of 2.7% for the patients in the positive FOBT cohort (Group A) is comparable with other studies. However, the diverticulosis group's CRC rate of 1.6% (Group B) was lower than in available published data.

Optimizing Fecal Occult Blood Test (FOBT) Colorectal Cancer Screening Using Gut Bacteriome as a Biomarker

BackgroundColorectal cancer (CRC) is a major cause of cancer mortality in the world. One of the most widely used screening tests for CRC is the immunochemical fecal occult blood test (iFOBT), which detects human hemoglobin from patient's stool sample. Although it is highly efficient in detecting blood from patients with gastro-intestinal lesions, such as polyps and cancers, the iFOBT has a high rate of false positive discovery. Recent studies suggested gut bacteria as a promising noninvasive biomarker for improving the diagnosis of CRC. In this study, we examined the composition of gut bacteria using iFOBT leftover from patients undergoing screening test along with a colonoscopy. MethodsAfter collecting data from more than 800 patients, we considered 4 groups for this study. The first and second groups were respectively “healthy” in which the patients had either no blood in their stool or had blood but no lesions. The third and fourth groups of patients had both blood in their stools with precancerous and cancerous lesions and considered either as low-grade and high-grade lesion groups, respectively. An amplification of 16S rRNA (V4 region) gene was performed, followed by sequencing along with various statistical and bioinformatic analysis. ResultsWe analyzed the composition of the gut bacteriome at phylum, class, genus, and species levels. Although members of the Firmicute phylum increased in the 3 groups compared to healthy patients, the phylum Actinobacteriota was found to decrease. Moreover, Blautia obeum and Anaerostipes hadrus from the phylum Firmicutes were increased and Collinsella aerofaciens from phylum Actinobacteriota was found decreased when healthy group is compared to the patients with high-grade lesions. Finally, among the 5 machine learning algorithms used to perform our analysis, both elastic net (AUC > 0.7) and random forest (AUC > 0.8) performs well in differentiating healthy patients from 3 other patient groups having blood in their stool. ConclusionOur study integrates the iFOBT screening tool with gut bacterial composition to improve the prediction of CRC lesions.

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.

Screening for Colorectal Cancer in Asymptomatic Average-Risk Adults: A Guidance Statement From the American College of Physicians (Version 2).

The purpose of this updated guidance statement is to guide clinicians on screening for colorectal cancer (CRC) in asymptomatic average-risk adults. The intended audience is all clinicians. The population is asymptomatic adults at average risk for CRC. This updated guidance statement was developed using recently published and critically appraised clinical guidelines from national guideline developers since the publication of the American College of Physicians' 2019 guidance statement, "Screening for Colorectal Cancer in Asymptomatic Average-Risk Adults." The authors searched for national guidelines from the United States and other countries published in English using PubMed and the Guidelines International Network library from 1 January 2018 to 24 April 2023. The authors also searched for updates of guidelines included in the first version of our guidance statement. The Appraisal of Guidelines for Research and Evaluation II (AGREE II) instrument was used to assess the quality of eligible guidelines. Two guidelines were selected for adoption and adaptation by raters on the basis of the highest average overall AGREE II quality scores. The evidence reviews and modeling studies for these 2 guidelines were also used to synthesize the evidence of diagnostic test accuracy, effectiveness, and harms of CRC screening interventions and to develop our guidance statements. Clinicians should start screening for colorectal cancer in asymptomatic average-risk adults at age 50 years. Clinicians should consider not screening asymptomatic average-risk adults between the ages of 45 to 49 years. Clinicians should discuss the uncertainty around benefits and harms of screening in this population. Clinicians should stop screening for colorectal cancer in asymptomatic average-risk adults older than 75 years or in asymptomatic average-risk adults with a life expectancy of 10 years or less. Clinicians should select a screening test for colorectal cancer in consultation with their patient based on a discussion of benefits, harms, costs, availability, frequency, and patient values and preferences. Clinicians should select among a fecal immunochemical or high-sensitivity guaiac fecal occult blood test every 2 years, colonoscopy every 10 years, or flexible sigmoidoscopy every 10 years plus a fecal immunochemical test every 2 years as a screening test for colorectal cancer. Clinicians should not use stool DNA, computed tomography colonography, capsule endoscopy, urine, or serum screening tests for colorectal cancer.

Hot Mail: Temperature Exposure during Mail Return of an Immunochemical Fecal Occult Blood Test.

Fecal immunochemical tests (FITs) are widely used for colorectal cancer (CRC) screening; however, high ambient temperatures were found to reduce test accuracy. More recently, proprietary globin stabilizers were added to FIT sample buffers to prevent temperature-associated hemoglobin (Hb) degradation, but their effectiveness remains uncertain. We aimed to determine the impact of high temperature (>30°C) on OC-Sensor FIT Hb concentration with current FITs, characterize FIT temperatures during mail transit, and determine impact of ambient temperature on FIT Hb concentration using data from a CRC screening program. FITs were analyzed for Hb concentration after in vitro incubation at different temperatures. Data loggers packaged alongside FITs measured temperatures during mail transit. Separately, screening program participants completed and mailed FITs to the laboratory for Hb analysis. Regression analyses compared the impact of environmental variables on FIT temperatures and separately on FIT sample Hb concentration. In vitro incubation at 30 to 35°C reduced FIT Hb concentration after >4 days. During mail transit, maximum FIT temperature averaged 6.4°C above maximum ambient temperature, but exposure to temperature above 30°C was for less than 24 hours. Screening program data showed no association between FIT Hb concentration and maximum ambient temperatures. Although FIT samples are exposed to elevated temperatures during mail transit, this is brief and does not significantly reduce FIT Hb concentration. These data support continuation of CRC screening during warm weather with modern FITs with a stabilizing agent when mail delivery is ≤4 days.

Engaging lower screening groups: a field experiment to evaluate the impact of a multiwave national campaign on participation in the National Bowel Cancer Screening Program

ObjectivesThis field study evaluated a multiwave media campaign that aired in 2019 to promote participation in the Australian National Bowel Cancer Screening Program (NBCSP), which provides free biennial mailed-out immunochemical...

A multicenter, case-control study of a novel multi-target fecal DNA test for colorectal cancer detection.

26 Background: Globally, colorectal cancer (CRC) is the fourth most frequently occurring cancer and is the second leading cause of cancer-related deaths. Early detection and diagnosis of pre-cancer lesions and CRCs at curable stages could prevent the disease or improve patient survival. Colonoscopy, the current gold-standard approach for CRC screening, is an invasive procedure, and novel non-invasive alternatives are needed. Methods: In present study, we developed a novel multi-target fecal DNA based assay, which integrates detection of two stool DNA (sDNA) methylation markers by quantitative methylation-specific PCR (qMSP) and immunochemical fecal occult blood test. We performed a multi-center case-control study to validate the diagnostic performance of this novel multi-target assay. Thus far, we collected stool specimens from a total of 784 subjects including CRC, advanced adenoma, nonadvanced neoplasms and individuals with negative findings on colonoscopy from six sites across China. All participants underwent colonoscopy; the stool specimens were tested with the multi-target fecal DNA test as well as a quantitative FIT test (OC FIT-CHEK, Eiken) in parallel in order to perform head-to-head comparison of the test performance of both assays. Results: The multi-target fecal DNA test demonstrated a higher sensitivity (96.1%) than FIT (85.3%) for CRCs (n=204). Meanwhile, 20 of 39 (51.3%) patients with advanced adenoma tested positive by the fecal DNA test, which was remarkably superior to FIT (7 of 39 tested positive, 17.9%). Among 541 participants with nonadvanced neoplasms or negative findings on colonoscopy, the specificity of the DNA test was 86.9%, compared with a specificity of 93.1% achieved by FIT. Within the control group, the DNA test and FIT yielded a specificity of 90.5% and 94.9% respectively for individuals with negative results on colonoscopy. Conclusions: The novel multi-target fecal DNA test exhibited notably superior sensitivity for both CRC and advanced adenoma cases than the commercially quantitative FIT test, while sacrificing some specificity. Our results suggest that this novel multi-target fecal based test may be used as an effective tool for early detection and pre-screening of CRC. Prospective study will be conducted to further evaluate the clinical performance and cost-effectiveness of this assay.

Implementation of a home-based colorectal cancer screening intervention in Malaysia (CRC-SIM)

IntroductionThe Colorectal Cancer Screening Intervention for Malaysia (CRC-SIM) was a CRC study of home-based testing designed to improve low screening uptake using the immunochemical fecal occult blood test (iFOBT) in Malaysia.MethodsThis quasi-experimental study was informed by the Implementation Research Logic Model and evaluated with the RE-AIM framework. Trained data collectors recruited by phone, randomly selected, asymptomatic adults aged 50-75 years from Segamat District, who previously completed a health census form for the South East Asia Community Observatory (SEACO). Participants were posted an iFOBT kit and asked to return a photo of the completed test for screening by health care professionals. A regression analysis of evaluation data was conducted to identify which variables were associated with the outcome indicators of ‘study participation’ and ‘iFOBT completion’ and the CRC-SIM was evaluated in terms of its appropriateness, feasibility and acceptability.ResultsSeven hundred forty-seven eligible adults (52%) agreed to participate in this study and received an iFOBT kit. Participation was significantly lower amongst Chinese Malaysians (adjusted OR 0.45, 95% CI 0.35 - 0.59, p<0.001) compared to Malays and amongst participants from the rural sub-district (Gemereh) (adjusted OR 0.71, 95% CI 0.54 - 0.92, p=0.011) compared to the urban sub-district (Sungai Segamat). Less than half of participants (42%, n=311/747) completed the iFOBT. Test-kit completion was significantly higher amongst Chinese Malaysians (adjusted OR 3.15, 95% CI 2.11 - 4.69, p<0.001) and lower amongst participants with a monthly household income ≥RM 4,850 (adjusted OR 0.58, 95% CI 0.39 - 0.87, p=0.009) compared to participants with a lower household income. The main reported reason for non-participation was ‘not interested’ (58.6%) and main implementation challenges related to invalid photographs from participants and engaging iFOBT positive participants in further clinic consultations and procedures.ConclusionHome-testing for CRC (test completion) appeared to be acceptable to only around one-fifth of the target population in Malaysia. However, mindful of the challenging circumstances surrounding the pandemic, the CRC-SIM merits consideration by public health planners as a method of increasing screening in Malaysia, and other low- and middle-income countries.

Colonoscopies in Australia – how much does the National Bowel Cancer Screening Program contribute to colonoscopy use?

Objectives and importance of study: Colorectal cancer (CRC) is Australia’s fourth most commonly diagnosed cancer. CRC screening is an effective intervention to reduce this burden. The National Bowel Cancer Screening Program (NBCSP) provides 2-yearly immunochemical faecal occult blood tests (iFOBTs) to Australians aged 50–74 years; a diagnostic colonoscopy is conducted after a positive iFOBT. Clinical guidelines inform colonoscopy usage, and appropriate use of these guidelines is vital to investigate gastrointestinal symptoms, detect bowel abnormalities and CRC, and remove precancerous polyps. Colonoscopy services are under strain, with limited formal strategies to prioritise patients. There are concerns among practitioners and patient advocates that the NBCSP generates additional colonoscopy requests and increases wait times, worsening patient outcomes and prolonging distress. In this research study, we estimate and project colonoscopy use in Australia from 2001 to 2030 and determine the impact of the NBCSP by examining model-estimated NBCSP colonoscopy demand. Methods: Colonoscopy use in Australia was compiled using Medicare Benefits Schedule (MBS) claims for colonoscopies from 2001 to 2019. From these data, projections were made from 2020 to 2030. Policy1-Bowel, a microsimulation model, was used to estimate NBCSP-related colonoscopy demand from screening follow-up and colonoscopic surveillance from 2006 to 2030. Results: MBS-funded colonoscopy use increased from 284 676 in 2001 to 663 213 in 2019. Annual use is projected to be more than 780 000 by 2030. Of these, 10–14% are projected to be generated by the NBCSP. Per-capita MBS-funded colonoscopy utilisation increased 0.2% annually over 2015–2019, a slowing of growth compared to previous trends. Conclusion: The NBCSP accounts for a modest fraction of colonoscopy use in Australia, and a better understanding of colonoscopy use not associated with the NBCSP is needed. Promoting adherence to guideline-recommended iFOBT and colonoscopy use could ease pressure on services and improve outcomes.

Improving colonoscopy prioritisation and promoting the National Bowel Cancer Screening Program: keys to reducing bowel cancer burden.

Australia's National Bowel Cancer Screening Program (NBCSP) has the potential to prevent almost 84 000 bowel cancer deaths if 60% program participation rates could be reached and maintained over the next two decades. Immunochemical faecal occult blood test (iFOBT) is used as an initial screening tool. Participants who test positive are referred for colonoscopy for diagnostic assessment. Concerns about colonoscopy capacity and lengthy wait times between positive iFOBT and colonoscopy have hampered efforts to promote the program. However, a separate research paper published in this issue of PHRP shows that only an estimated 10-14% of Medicare-funded colonoscopies (almost 75% of all colonoscopies) in Australia are generated by the NBCSP. Inappropriate use of colonoscopy as a primary screening tool and failure to prioritise NBCSP participants may be the main reasons for long colonoscopy wait times associated with the program. Promoting clinical practice guidelines, and the Direct Access Colonoscopy initiative for priority patients, are key to reducing colonoscopy wait times and proactive promotion of the NBCSP.

Facilitators and barriers to colorectal cancer screening using the immunochemical faecal occult blood test among an average-risk population in semi-rural Malaysia: A qualitative study.

Colorectal cancer (CRC) incidence in Malaysia is increasing, and most CRC patients are diagnosed at a late stage. This study investigated participant awareness of CRC and their perceptions and views about CRC screening, barriers, benefits, and facilitators towards CRC screening participation as well as health-seeking behaviour and the use of preventative health services. Eleven focus group discussions (FGDs) were conducted with a purposive sample of 89 participants aged > 50 from the major ethnic groups in the Segamat District, Johor State. FGDs were audiotaped, transcribed verbatim, and translated into English. Data were analysed using thematic analysis. We identified trust in doctors as a key reason for whether or not to seek health care. Generally, the participants had low awareness of CRC sign/symptoms and screening. Emotional and logistic concerns about sending a stool sample to a clinic emerged as the main barriers to screening. Simplified illustrated instructions about stool collection in Malay, Chinese and Tamil, free screening at health clinics and reminders to complete the iFOBT test were perceived to facilitate engagement in screening, and posited as strategies that were likely to increase iFOBT uptake. Primary care physicians play a crucial role in terms of reducing patient's misperceptions, recommending screening to patients, enhancing attendance, and improving uptake of CRC screening. There is a need for further research to investigate ways in which to reduce identified barriers and implement and test potential facilitative strategies as well as examine adherence by doctors to clinical guidelines about CRC screening.

Colonoscopies in Australia - how much does the National Bowel Cancer Screening Program contribute to colonoscopy use?

Colonoscopy use in Australia was compiled using Medicare Benefits Schedule (MBS) claims for colonoscopies from 2001 to 2019. From these data, projections were made from 2020 to 2030. Policy1-Bowel, a microsimulation model, was used to estimate NBCSP-related colonoscopy demand from screening follow-up and colonoscopic surveillance from 2006 to 2030. MBS-funded colonoscopy use increased from 284 676 in 2001 to 663 213 in 2019. Annual use is projected to be more than 780 000 by 2030. Of these, 10-14% are projected to be generated by the NBCSP. Per-capita MBS-funded colonoscopy utilisation increased 0.2% annually over 2015-2019, a slowing of growth compared to previous trends. The NBCSP accounts for a modest fraction of colonoscopy use in Australia, and a better understanding of colonoscopy use not associated with the NBCSP is needed. Promoting adherence to guideline-recommended iFOBT and colonoscopy use could ease pressure on services and improve outcomes.

Spike in peptic ulcer disease in pregnancy in a rural community of Enugu state, southeast Nigeria: is this an epidemic?

Background: Pregnancy is said to increase susceptibility to Helicobacter pylori (H. pylori) infection, probably due to decreased cell-mediated cytotoxic immune response. Despite this, evidence from epidemiological studies suggest an alleviation of peptic ulcer disease (PUD) during pregnancy. One study found the incidence of PUD among pregnant women to be as low as 0.005-0.03%. The present study aimed to determine the incidence of PUD in women who attended ante-natal clinic in Cottage Hospital Inyi, Oji River Local Government Area (LGA), Enugu State, in 2021.Methods: This was a cross-sectional study conducted with 435 pregnant women, aged 18- 40 years in 2021 in Inyi, Oji River LGA of Enugu State, Southeast Nigeria. Through purposeful sampling, 57 women were selected. From each of these patients, a stool sample was collected and examined using immunochemical fecal occult blood test. A horizontal line on the test strip signified a positive result, while its absence negative result. Data were analysed as proportion and Chi- square using MaxStat (version 3.6) statistical software. P value ≤0.05 was considered significant.Results: The incidence of PUD in the pregnant women was 13%; 4.8% in primigravidae, and 8.2% in multigravidae. The association between PUD and parity was not significant (p value =0.89).Conclusions: The incidence of PUD in pregnancy (13%) was much higher than ever had been reported in the past, being slightly higher in multigravidae than primigravidae. Health education on lifestyle modification and environmental sanitation could help in tackling this problem.

Immunochemical Fecal Occult Blood Test Screening Results prior to Colorectal Cancer Diagnosis

Abstract Introduction/Objective Immunochemical fecal occult blood testing (iFOBT) is one of the options outlined by the standard of care guidelines from the U.S. Preventive Services Task Force (USPSTF) for screening for colorectal cancer in adults. The iFOBT assay is a convenient and reasonably accurate screening assay. It has been shown in the literature, through a metanalysis of iFOBT tests, that the overall sensitivity of iFOBT in the general population for detecting colorectal cancer within 2 years of follow-up across different medical settings is 0.79 (95% confidence interval 0.69-0.86). However, similar investigation in the veteran population is sparse, but would be important given the significant differences between the Veteran population and the general population including increased medical comorbidities. Methods/Case Report A search of all iFOBT testing performed at a regional Veteran Affairs Medical Center (VAMC) from 10/1/2018 to 6/4/2022 was performed to identify patients with both diagnosed colorectal cancer by pathology examination and iFOBT testing within 2 years prior to this diagnosis. The iFOBT result (at least one positive prior to diagnosis or always negative) prior to diagnosis with colorectal cancer was recorded once per patient. iFOBT results collected after the day the positive colorectal pathology specimen was obtained were excluded. Demographic information was also recorded. iFOBT testing was performed using the Polymedco assay product (Cortlandt Manor, NY). Results (if a Case Study enter NA) There were a total of 26 patients (25 males and 1 female) with diagnosed colorectal cancer. The patient age range was 37 to 88 years (average 70) with an ethnic composition of 12 of 26 (46%) African Americans, 13 of 26 (50%) Caucasian American, and 1 of 26 (4%) Native Hawaiian or other Pacific Islander American. 20 of the 26 patients (77%) of the patients had at least one positive iFOBT test result prior to their colorectal cancer diagnosis, which is within the published observation for the accepted sensitivity in the general population. Conclusion While there are differences between the general population and the veteran population in terms of medical comorbidities, the iFOBT test assay performed similarly to the general population in terms of sensitivity for colorectal cancer diagnosed within 2 years of the iFOBT assay and remains an important part of the standard of care for colorectal screening for both populations.

Je možné individualizovat vysazení antikoagulační terapie před preventivní koloskopií?

Summary: Background: Hot-snare polypectomy is a standard method for removal of polyps larger than 10 mm. It is recommended to discontinue anticoagulant therapy before this procedure to reduce a bleeding risk. In contrast, diagnostic colonoscopy and cold-snare polypectomy up to 10 mm are considered safe during uninterrupted anticoagulation therapy (with only omission of the direct oral anticoagulant therapy on the day of the procedure). The increasing number of anticoagulated individuals undergoing a colorectal cancer screening program leads to efforts to individualize the interruption of anticoagulation therapy. Aim: Estimation of probability that adenomatous polyp over 10 mm is detected during preventive colonoscopy in the Czech Republic in particular population groups according to gender and age. Methods: We retrospectively analyzed data from prospective database (Registry of Preventive Colonoscopies) covering screening colonoscopies and colonoscopies indicated for immunochemical faecal occult blood test positivity (FIT-positive). A distinction was made between adenoma polyps ≤10 mm and &gt;10 mm. The patient was categorized according to the largest polyp diameter in case of detection of multiple polyps. Results: Between 2016 and 2020, 16,942 and 52,052 adenomatous polyps were found during 55,546 screenings and 119,229 FIT-positive colonoscopies, representing adenoma detection rate (ADR) of 31% and 44%, respectively. The estimate of probability of significant polyp detection (over 10 mm) and the need of hot-snare polypectomy ranged widely (2.3–21.6%) depending on age, sex and indication. It can be estimated to 7% in females and 5–10% in males undergoing screening colonoscopy. For colonoscopies indicated for positive stools for occult bleeding, this probability is approximately two to three times higher in FIT-positive colonoscopies: it exceeds 10% in woman over 60 years of age and is 15% and more in men of all ages (over 20% in men over 60 years of age). Conclusions: The decision to discontinue anticoagulation therapy prior to preventive colonoscopy can be individualized with respect to the indication (screening vs. FIT-positive), age and gender of examined person – we prefer to discontinue the anticoagulation therapy in FIT-positive people over 60 years and/or of male gender. The individual thromboembolic risk during interruption of anticoagulation therapy must be considered depending on the specific indication (e. g. CHA2DS2 VASc score in atrial fibrillation). Key words: colonoscopy – anticoagulant therapy – direct-acting oral anticoagulants – cancer screening – personalized medicine

To scope or not - the challenges of managing patients with positive fecal occult blood test after recent colonoscopy.

BACKGROUNDColorectal cancer (CRC) is a major health problem. There is minimal consensus of the appropriate approach to manage patients with positive immunochemical fecal occult blood test (iFOBT), following a recent colonoscopy.AIMTo determine the prevalence of advanced neoplasia in patients with a positive iFOBT after a recent colonoscopy, and clinical and endoscopic predictors for advanced neoplasia.METHODSThe study recruited iFOBT positive patients who underwent colonoscopy between July 2015 to March 2020. Data collected included demographics, clinical characteristics, previous and current colonoscopy findings. Primary outcome was the prevalence of CRC and advanced neoplasia in a patient with positive iFOBT and previous colonoscopy. Secondary outcomes included identifying any clinical and endoscopic predictors for advanced neoplasia.RESULTSThe study included 1051 patients (male 53.6%; median age 63). Forty-two (4.0%) patients were diagnosed with CRC, 513 (48.8%) with adenoma/sessile serrated lesion (A-SSL) and 257 (24.5%) with advanced A-SSL (AA-SSL). A previous colonoscopy had been performed in 319 (30.3%). In this cohort, four (1.3%) were diagnosed with CRC, 146 (45.8%) with A-SSL and 56 (17.6%) with AA-SSL. Among those who had a colonoscopy within 4 years, none had CRC and 7 had AA-SSL. Of the 732 patients with no prior colonoscopy, there were 38 CRCs (5.2%). Independent predictors for advanced neoplasia were male [odds ratio (OR) = 1.80; 95% confidence interval (CI): 1.35-2.40; P < 0.001), age (OR = 1.04; 95%CI: 1.02-1.06; P < 0.001) and no previous colonoscopy (OR = 2.07; 95%CI: 1.49-2.87; P < 0.001).CONCLUSIONA previous colonoscopy, irrespective of its result, was associated with low prevalence of advanced neoplasia, and if performed within four years of a positive iFOBT result, was protective against CRC.

Associations of red and processed meat intake with screen-detected colorectal lesions.

Limited data exist regarding the role of meat consumption in early-stage colorectal carcinogenesis. We examined associations of red and processed meat intake with screen-detected colorectal lesions in immunochemical fecal occult blood test (FIT)-positive participants, enrolled in the Norwegian CRCbiome study during 2017-2021, aged 55-77 years. Absolute and energy-adjusted intakes of red and processed meat (combined and individually) were assessed using a validated, semiquantitative food frequency questionnaire. Associations between meat intake and screen-detected colorectal lesions were examined using multinomial logistic regression analyses with adjustment for key covariates. Of 1,162 participants with available dietary data, 319 (27%) presented with advanced colorectal lesions at colonoscopy. High vs low energy-adjusted intakes of red and processed meat combined, as well as red meat alone, were borderline to significantly positively associated with advanced colorectal lesions (ORs (95% CIs) of 1.24 (0.98, 1.57) and 1.34 (1.07, 1.69), respectively). A significant dose-response-relationship was also observed for absolute intake levels (OR (95% CI) of 1.32 (1.09, 1.60) per 100 g/day increase in red and processed meat). For processed meat, no association was observed between energy-adjusted intakes and advanced colorectal lesions. A significant positive association was, however, observed for the small proportion of participants (10%) with absolute intake levels ≥100 vs <50 g/day (OR (95% CI) of 1.19 (1.09, 1.31)). In summary, high intakes of red and processed meat were associated with presence of advanced colorectal lesions at colonoscopy in FIT-positive participants. The study demonstrates a potential role of using dietary data to improve the performance of FIT-based screening.

Colon Capsule Endoscopy in the Diagnosis of Colon Polyps: Who Needs a Colonoscopy?

Colon screening programs have reduced colon cancer mortality. Population screening should be minimally invasive, safe, acceptably sensitive, cost-effective, and scalable. The range of screening modalities include guaiac or immunochemical fecal occult blood testing and CT colonography and colonoscopy. A number of carefully controlled studies concur that second-generation capsule endoscopy has excellent sensitivity for polyp detection and a high negative predictive value. Colon capsules fulfill the screening expectation of safety, high sensitivity for polyp detection, and patient acceptance, and appear to straddle the divide between occult blood testing and colonoscopy. While meeting these criteria, there remains the challenges of scaling, capsule practitioner training, resource allocation, and implementing change of practice. Like CT colonography, capsule screening presents the clinician with a decision on the threshold for colonoscopy referral. Overall, colon capsules are an invaluable tool in polyp detection and colon screening and offer a filter that determines “who needs a colonoscopy?”.

When History and Heterogeneity Matter: A Tutorial on the Impact of Markov Model Specifications in the Context of Colorectal Cancer Screening.

Markov models are used in health research to simulate health care utilization and disease states over time. Health phenomena, however, are complex, and the memoryless assumption of Markov models may not appropriately represent reality. This tutorial provides guidance on the use of Markov models of different orders and stratification levels in health decision-analytic modeling. Colorectal cancer (CRC) screening is used as a case example to examine the impact of using different Markov modeling approaches on CRC outcomes. This study used insurance claims data from commercially insured individuals in Oregon to estimate transition probabilities between CRC screening states (no screen, colonoscopy, fecal immunochemical test or fecal occult blood test). First-order, first-order stratified by sex and geography, and third-order Markov models were compared. Screening trajectories produced from the different Markov models were incorporated into a microsimulation model that simulated the natural history of CRC disease progression. Simulation outcomes (e.g., future screening choices, CRC incidence, deaths due to CRC) were compared across models. Simulated CRC screening trajectories and resulting CRC outcomes varied depending on the Markov modeling approach used. For example, when using the first-order, first-order stratified, and third-order Markov models, 30%, 31%, and 44% of individuals used colonoscopy as their only screening modality, respectively. Screening trajectories based on the third-order Markov model predicted that a higher percentage of individuals were up-to-date with CRC screening as compared with the other Markov models. The study was limited to insurance claims data spanning 5 y. It was not possible to validate which Markov model better predicts long-term screening behavior and outcomes. Findings demonstrate the impact that different order and stratification assumptions can have in decision-analytic models. This tutorial uses colorectal cancer screening as a case example to provide guidance on the use of Markov models of different orders and stratification levels in health decision-analytic models.Colorectal cancer screening trajectories and projected health outcomes were sensitive to the use of alternate Markov model specifications.Although data limitations precluded the assessment of model accuracy beyond a 5-y period, within the 5-y period, the third-order Markov model was slightly more accurate in predicting the fifth colorectal cancer screening action than the first-order Markov model.Findings from this tutorial demonstrate the importance of examining the memoryless assumption of the first-order Markov model when simulating health care utilization over time.

Comparison of faecal protein biomarkers' diagnostic accuracy for colorectal advanced neoplasms: a systematic review and meta-analysis

Early diagnosis of colorectal advanced neoplasms (ANs), including colorectal cancer (CRC) and advanced adenoma (AA), has a positive effect on the survival rate. As a first attempt, the aim of this meta-analysis was to compare the diagnostic accuracy of faecal protein biomarkers for the detection of colorectal neoplasms with consideration of a wide range of covariates. A systematic literature search was performed up to Jun 10, 2021 on Web of Sciences, Scopus and PubMed. The diagnostic accuracies were calculated using the bivariate/hierarchical random effect model. Biomarkers were determined to be clinically applicable (CA) if they had areas under the curve > 0.70 and positive and negative likelihood ratios > 2 and < 0.5, respectively. A total of 47,059 test results were extracted from 16 immunochemical faecal occult blood test (iFOBT), 26 pyruvate kinase-M2 (PK-M2) and 23 faecal calprotectin (FC) studies. Only iFOBT, PK-M2 and FC for CRC plus iFOBT and PK-M2 for AN were CA. iFOBT had significantly superior accuracy (P = 0.02 versus PK-M2 and P < 0.01 versus FC for CRC; P < 0.01 versus PK-M2 for AN). Regarding covariates, the lateral flow method of PK-M2 measurement increased its accuracy for CRC detection compared to the enzyme-linked immunosorbent assay (P < 0.01). iFOBT is recommended as the most accurate faecal biomarker for CRC and AN diagnosis.