Colorectal Screening Program Research Articles

Colorectal screening program implementation in primary health care, in Loures-Odivelas, Portugal

Abstract Problem In 2020, Portugal had the highest cumulative incidence of colorectal cancer (CRC) in the European Union (103 new cases/100,000 inhabitants). The Colorectal Cancer Screening Program (CRCS) is based on fecal occult blood testing (FOBT) as the primary screening method. With the delivery of the stool sample collection device; instruction on its use is provided by the Primary Health Care team. The sample is processed at the Clinical Pathology laboratory of the Hospital Center (HC). In case of a positive result, the general practitioner communicates the result and refers the individual to the Follow-up and Treatment Center. Description The general objective of this project was to implement the CRCS in the 19 Family Health Units (FHU) of Loures-Odivelas Health Center Group, between September 2022 and April 2023. The following activities were carried out: 1. Sessions to present the patient pathway, record platform, and stool sample collection device; 2. Application of a checklist of essential points for the start of screening; 3. Preparation and dissemination of monitoring reports to the FHU; 4. Follow-up visits to clarify doubts. Results By March 2023, CRCS had been implemented in 15 of the 19 FHU (79%). Between September 2022 and March 2023, 1,430 devices were delivered and 959 FOBT samples were received (67%). Among the devices received with biological samples, it was not possible to issue a result for 5%. Lessons The activities carried out allowed for the initiation of CRCS in most FHU. The involvement of professionals in these activities contributes to increased patient adherence and proper collection technique, reducing inconclusive FOBT results. It is necessary to continue this strategy of personalized support for the FHU to consolidate the implementation of CRCS in LO HCG. Ensuring that the necessary materials are available and that result issuance and referral deadlines are met are important factors for maintaining professional motivation. Key messages • The objective was to implement the Colorectal Cancer Screening Program (CRCS) in 19 Family Health Units (FHU) in Loures-Odivelas. By March 2023, CRCS had been implemented in 15 of 19 FHU (79%). • It is important to continue these activities in order to put into operation the CRCS in all FHU and to tackle the problem of colorectal cancer.

P282 An evaluation of concurrent FIT and colonoscopies as part of the colorectal screening programme for patients with cystic fibrosis. Is FIT fit for purpose?

P282 An evaluation of concurrent FIT and colonoscopies as part of the colorectal screening programme for patients with cystic fibrosis. Is FIT fit for purpose?

Interval Cancer in Population-Based Colorectal Screening Programmes: Incidence and Characteristics of Tumours.

The objective of this study is to evaluate interval cancer (IC) in colorectal cancer (CRC) screening, which is CRC diagnosed in an individual after having received a negative faecal occult blood test and before the next invitation to participate in screening. A follow-up study was conducted on a cohort of participants in the first three screening rounds of four colorectal cancer screening programmes in Spain, n = 664,993. A total of 321 ICs and 2120 screen-detected cancers (SCs) were found. The IC and SC rates were calculated for each guaiac (gFOBT) or immunochemical (FIT) test. A Cox regression model was used to estimate the hazard ratios (HR) of IC risk factors. A nested case-control study was carried out to compare IC and SC tumour characteristics. The IC rate was 1.16‱ with the gFOBT and 0.35‱ with the FIT. Men and people aged 60-69 showed an increased probability of IC (HR = 1.81 and HR = 1.95, respectively). There was a decreased probability of IC in individuals who regularly participated in screening, HR = 0.62 (0.47-0.82). IC risk gradually rose as the amount of Hb detected in the FIT increased. IC tumours were in more advanced stages and of a larger size than SC tumours, and they were mostly located in the cecum. These results may play a key role in future strategies for screening programmes, reducing IC incidence.

Deficient mismatch repair screening of advanced adenomas in the population screening program for colorectal cancer is not effective.

Currently, screening of colorectal cancers (CRC) by assessing mismatch repair deficiency (dMMR) or microsatellite instability (MSI) is used to identify Lynch syndrome (LS) patients. Advanced adenomas are considered immediate precursor lesions of CRC. In this study we investigate the relevance of screening of advanced adenomas for LS in population screening. Advanced adenomas (n = 1572) were selected from the Dutch colorectal cancer population screening programme, based on one or more of the criteria: tubulovillous (n = 848, 54%) or villous adenoma (n = 118, 7.5%), diameter ≥ 1 cm (n = 1286, 82%) and/or high-grade dysplasia (n = 176, 11%). In 86 cases (5%), all three criteria were fulfilled at the same time. MMR-IHC and/or MSI analyses were performed on all cases. Only five advanced adenomas (0.3%) showed dMMR and MSI, including two cases with hypermethylation. In at least two patients a germline event was suspected based on allelic frequencies. No pathogenic explanation was found in the last case. Timely testing of precursor lesions would be preferable to detect new LS patients before CRC development. However, standard assessment of dMMR of advanced adenomas from the population screening is not effective.

Abstract C114: Indigenizing and ruralizing NCI’s Screen to Save Program: Resources, Optimizing Outreach, Teaching, Science (ROOTS)

Abstract Resources, Optimizing Outreach, Teaching and Science (ROOTS) for Indigenous populations was a virtually adapted colorectal screening program to decrease cancer health disparities while increasing knowledge about culturally tailored screening processes. Indigenous and rural community outreach teams partnered with a community advisory board to provide an Indigenized/ruralized version of the NCI Screen to Save (S2S) program delivered to both Indigenous rural/sub-urban communities. 169 pre/post surveys were obtained from 82 participants. Findings demonstrated participants were able to identify smoking, tobacco use, and lack of physical activity as risk factors for colorectal cancer. Post intervention, participants were more likely to get screened for colorectal cancer and talk with family friends about their colorectal cancer screening experience increase physical activity. Additional adaptions were investigated for Two-Spirit and Native American lesbian, gay, bisexual, transgender, queer, questioning, intersex, asexual urban populations (n=6 virtual roundtables; n=14 participants). Findings from the overall ROOTS program suggested culturally tailored intervention messaging are an important means for increasing screening and decreasing cancer health disparities among both Indigenous and rural populations. Primary results from Two Spirit and LGBTQ+ adaption included understanding past mindsets and experiences of healthcare professionals; a need for continued lay translations, importance of community marketing beyond health centers; and more information on follow up details including central contact information. Citation Format: Rodney C. Haring, William Maybee, Josie Raphaelito, Corrine Abrams. Indigenizing and ruralizing NCI’s Screen to Save Program: Resources, Optimizing Outreach, Teaching, Science (ROOTS) [abstract]. In: Proceedings of the 16th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2023 Sep 29-Oct 2;Orlando, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2023;32(12 Suppl):Abstract nr C114.

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.

Epidemiology, Risk Factors for Gastric Cancer and Surveillance of Premalignant Gastric Lesions: A Prospective Cohort Study of Central Saudi Arabia.

(1) Background: Saudi Arabia (SA) is a country with a low incidence of gastric cancer (GC). In this study, we sought to assess the epidemiology of GC, its clinicopathological profiles, and its association with risk factors as well as to identify premalignant gastric lesions (PGL) and examine neoplastic progression. (2) Methods: This five-year prospective study screened for GC and PGL in asymptomatic Saudi patients, aged 45-75 years (n = 35,640) and living in Al Kharj, Riyadh province in central SA. Those who were positive in a high-sensitivity guaiac fecal occult blood test (HSgFOBT+) and had negative results in colonoscopy offered to undergo upper GI endoscopy (n = 1242). Factors associated with GC were examined. (3) Results: The five-year participation rate was 87% (1080/1242). The incidence rate of GC was 26.9 new cases per 100,000 population per year (9.6 new cases per year/total population at risk-35,640), and it was 8.9 cases per 1000 persons per year among the 1080 subjects with HSgFOBT+ and negative colonoscopy results. The five-year mortality rate was 67% among patients with GC (n = 48), 3.0% among participants in the gastric screening program (n = 1080) and 0.09% among the original population participating in the colorectal screening program (n = 35,640). Intestinal-type adenocarcinoma was the most frequent type (77%), with the tumor most commonly located in the antrum (41%). Overall, 334 participants had PGL, and seven of them (2.1%) showed neoplastic progression to GC during the follow-up. Factors associated with GC were age, Helicobacter pylori (HP) infection, obesity (body mass index BMI > 30), smoking, a diet of salty preserved foods, low income and a family history of GC. (4) Conclusions: The incidence of GC is low in central SA, but screening for PGL and GC among patients with HSgFOBT+ and negative colonoscopy may prevent or result in the early treatment of GC. HP eradication, normal body weight, not smoking and adhering to a healthy diet can reduce the risk of GC. The resulting data provide important input for the improvement of national guidelines.

The Influence of the COVID-19 Pandemic on Colorectal Cancer Secondary Preventive Healthcare Measures.

This study aims to assess the impact of SARS-CoV-2 on a population enrolled in a pilot colorectal screening program started by a family doctor in Romania. This observational retrospective study was spread over 43 months, respectively, from October 2019 to April 2023, and included 169 patients. The primary objective was to compare the pre-pandemic, pandemic, and post-pandemic periods to observe significant changes. The secondary objective was to study the correlation between vaccination against SARS-CoV-2 and participation in the study, especially in the age range class of interest-50-74 years. These data are important because Romanian Healthcare policymakers can use them to estimate the participation rate in a future national colorectal cancer screening and how to adjust and facilitate their communications with the targeted population. The rise of COVID-19 significantly negatively impacted the number of patients adhering to the pilot colorectal cancer screening and the number of test results during the pandemic period. However, in the post-pandemic period, the number of patients who joined the study, and the number of fecal occult blood tests was greater than expected (128.74%). We observed that screening participation was associated with vaccination (78.11% of patients had a complete COVID-19 vaccine scheme).

The community pharmacy model for colorectal cancer screening: Policy insights from a national programme

BackgroundIn Italy, a recent national project has expanded local collaboration between colorectal (CRC) screening programmes and pharmacies to the national level. ObjectiveThe objective of this study is to provide an overview of the existing agreements between regional authorities and pharmacy owners in Italy regarding CRC screening programmes, to make internationally available the most qualifying elements of the collaboration. MethodsWe analyzed the agreements, in force on 01/08/2021, arranged between the Regions and their respective pharmacy owners, describing the process phases addressed such as the faecal occult blood test pathway and supplementary activities provided by the pharmacies together with the CRC screening kit delivery. ResultsAgreements were received from 18 Regions (86% of the total). The amount of money paid for each kit varies a lot, with a range from 0 to 18 EUR. The number of process phases covered by the agreements ranged from a maximum of 16 (out of 18) to a minimum of 0. The processes most frequently covered were the supply/delivery of kits and education/awareness of CRC screening (68.8%). Less covered processes were warehouse management and awareness of other healthcare initiatives (12.5%), and delivery of preparation for intestinal cleansing (6.3%). ConclusionsArrangements between pharmacies and CRC screening programmes in Italy vary widely and lack a unified model. Collaboration quality standards should be set at the national/international level.

Interval cancers in a national colorectal screening programme based on faecal immunochemical testing: Implications for faecal haemoglobin concentration threshold and sex inequality.

To compare interval cancer proportions (ICP) in the faecal immunochemical test (FIT)-based Scottish Bowel Screening Programme (SBoSP) with the former guaiac faecal occult blood test (gFOBT)-based SBoSP and investigate associations between interval cancer (IC) and faecal haemoglobin concentration (f-Hb) threshold, sex, age, deprivation, site, and stage. The ICP data from first year of the FIT-based SBoSP and the penultimate year of the gFOBT-based SBoSP were compared in a prospective cohort design. With FIT, 801 colorectal cancers (CRCs) were screen detected (SDC), 802 were in non-participants, 548 were ICs, 39 were colonoscopy missed and 72 were diagnosed after incomplete screening; with gFOBT: 540, 904, 556, 45, and 13, respectively. FIT had a significantly higher proportion of SDC compared to IC than gFOBT. For FIT and gFOBT, ICP was significantly higher in women than men. As f-Hb threshold increased, ICP increased and, for any f-Hb threshold for men, a lower threshold was required for comparable ICP in women. In Scotland, the current threshold of ≥80 µg Hb/g faeces would have to be lowered to ≥40 µg Hb/g faeces for women to achieve sex equality for ICP. In the FIT-based SBoSP, there were four times as many stage I SDC than IC. This was reversed in advanced stages, with twice as many stage IV CRC diagnosed as IC versus SDC. Reducing the numbers of IC requires lowering the f-Hb threshold. Using different f-Hb thresholds for women and men could eliminate the sex disparity, but with additional colonoscopy.

Association between Sleep Duration and Colorectal Adenomas: Findings from a Case-Control Study in Vietnam.

Colorectal cancer is one of the leading cancers worldwide and in Vietnam. Adenomas are important precursors of colorectal cancer. Study on the association between sleep duration and development of colorectal adenoma (CRA) is limited, particularly among Vietnamese population. We conducted an individually matched case-control study of 870 CRA cases and 870 controls in a large-scale colorectal screening program involving 103,542 individuals ages ≥40 years old in Hanoi, Vietnam. Sleep duration was categorized in three groups: short: ≤6 hours/day, normal: 7 to 8 hours/day, and long: >8 hours/day. Conditional logistic regression was used to evaluate the association between sleep duration and adenomas risk after controlling for potential confounders. Overall, short-sleep duration was associated with increased risk of having CRA compared with normal duration [OR, 1.48; 95% confidence interval (CI), 1.12-1.97]. This pattern was present in both females (OR, 1.58; 95% CI, 1.14-2.18) and males (OR, 1.45; 95% CI, 1.08-1.93), with advanced adenomas (OR, 1.61; 95% CI, 1.09-2.38) and non-advanced adenomas (OR, 1.66; 95% CI, 1.19-2.32). Furthermore, the association between CRA development and short-sleep duration was more apparent among females who were nondrinker, nonobese, physically active, with proximal or both sided adenomas and with cardiometabolic disorder. Among males, the short-sleep duration was associated with CRA risk among never-smoking, cardiometabolic disorders, and obese. Short-sleep duration was associated with increased prevalence of both advanced and non-advanced CRAs among Vietnamese population. Findings from this study showed that maintaining an adequate sleep duration may have an important implication for colorectal adenoma prevention and control.

Intervening factors for participation and non-participation in colorectal cancer screening in Spain.

e22552 Background: The Spanish Ministry of Health introduced a population-based colorectal screening program within its common services portfolio in 2014. The program targeted adults from 50 to 69 years. They receive a personal invitation letter asking them to perform the fecal occult blood test (FOBT). To achieve public health benefits on incidence, mortality and cost-effectiveness from this screening program a 65% participation in the program is needed1.Although participation rates have been improved since 2014, there is still room from improvement as only 56% of the Spanish regions reach the participacion threshold2. In this study we examined attitudinal and social factors impacting on participation in the target population. Methods: A CAWI survey was conducted among the target population of the screening program using a nation-wide citizen panel. A representative sample of the Spanish population, with size of 5131 valid responses, was obtained. The fieldwork was conducted in June 22nd. The data was analyzed using a descriptive analysis for the entire sample as well as the logistic regression technique using the maximum likelihood estimation. This technique allows us to determine the variables that have the greatest predictive capacity with respect to the participation (or non-participation) on the (FOBT). Results: We found that 97.6% of people have heard of colon cancer, 86.8% are aware of the test, 72.5% have received the program information letter and 62.5% have performed the test (FOBT). Furthermore, logistic regression demonstrates that the reception of a program information letter (OR=7,381, p&lt;0.01), and the prior knowledge of the screening test (FOBT) (OR=6,768, p&lt;0,01) significantly predicted the participation. Other variables with a high contribution were age between 62-69 (OR= 1,470, p&lt;0.01), the frequency of routine medical check-ups (OR= 1,717, p&lt;0.01), a positive perception of routine medical checkups (OR= 1,659, p&lt;0.01), and personal risk of colon cancer perception (OR= 1,404, p&lt;0.01). Conclusions: The effective participation in the program is influenced by factors that are unrelated to the implementation process (including the reception of the invitation letter). Most influential factors on actual participation on the program are the prior knowledge of the program and the importance attributed to routine heath checkups. Specific interventions on these variables should be done concurrently with expanding coverage in order to achieve the goals of higher effective participation.

P-408 Costa Rica, an example of the Americas in the implementation of an innovative organized colorectal screening program during 2017–2022

P-408 Costa Rica, an example of the Americas in the implementation of an innovative organized colorectal screening program during 2017–2022

A95 ASSESSMENT OF BIRTH COHORT SCREENING OF CHRONIC HEPATITIS C IN COLORECTAL CANCER SCREENING PATIENTS IN BRITISH COLUMBIA

Abstract Background Birth cohort screening of chronic hepatitis C (CHC) is recommended in British Columbia since 2018 for baby boomers born between 1945 to 1964, with an estimated provincial prevalence of 2.31%. Though there remained a gap in care following anti-hepatitis C positivity, resulting in reflexive ribonucleic acid (RNA) testing provincially. Dual screening of CHC in patients referred to colorectal (CRC) screening programs can provide an opportunity to link patients with healthcare professionals to ensure appropriate follow-up. Purpose We aimed to assess the uptake of CHC screening amongst CRC screening patients after the release of British Columbia’s birth cohort guidelines, both pre and post-COVID-19 pandemic. Method A retrospective review of patients referred to a CRC screening program in Vancouver from October 1st to December 31st, 2019, and December 1st – 31st, 2021, was performed. Collected data included demographics, liver disease history, and co-infection rates with hepatitis B (HBV) or human immunodeficiency virus (HIV). Dates of first-time hepatitis C antibody, RNA and viral load testing were gathered. Descriptive statistics were used to identify the proportion of screening and prevalence of CHC. Result(s) A total of 553 patients were referred for colonoscopy to the CRC screening program, of whom 458 (82.8%) patients were born between 1945 to 1964, and 273 (n=49%) were female. Among the 250 (45.2%) patients screened for CHC, 4 (0.72%) had positive anti-hepatitis C, all of whom were baby boomers. In 2019, 44% (n=183) of patients were screened for CHC; 78.7% (n=144) were screened before colonoscopy referral. In 2020, 48.6% (n=67) of patients were screened for CHC; 100% of cases were screened before colonoscopy referral. Conclusion(s) Birth cohort screening of CHC is underutilized in British Columbia. Dual screening of CHC at the time of referral to CRC screening provides a practical approach to linking patients to healthcare. Please acknowledge all funding agencies by checking the applicable boxes below None Disclosure of Interest None Declared

Development of knowledge-based clinical decision support system for patients included in colorectal screening program

Colorectal (CRC) screening programs represent a large volume of procedures that need a follow-up endoscopy. A knowledge-based clinical decision support system (K-CDSS) is a technology which contains clinical rules and associations of compiled data that assist with clinical decision-making tasks. We develop a K-CDSS for management of patients included in CRC screening and surveillance of colorectal polyps. We collected information on 48 variables from hospital colonoscopy records. Using DILEMMA Solutions Platform © ( https://www.dilemasolution.com ) we designed a prototype K-CDSS (PoliCare CDSS), to provide tailored recommendations by combining patients data and current guidelines recommendations. The accuracy of rules was verified using four scenarios (normal colonoscopy, lesions different than polyps, non-advanced adenomas and advanced adenomas). We studied the degree of agreement between the clinical assessments made by expert doctors and nurses equipped with PoliCare CDSS. Two experts confirmed a correlation between guidelines and PoliCare recommendations. 56 consecutive endoscopy cases from colorectal screening program were included (62.8 years; range 53-71). Colonoscopy results were: absence of colon lesions ( n = 7, 12.5%), lesions in the colon that are not polyps ( n = 3, 5.4%) and resected colonic polyps ( n = 46, 82.1%; 100% R0 resection). Patients with resected polyps presented non-advanced adenoma ( n = 21, 45.6%) or advanced lesions ( n = 25, 54.4%). There were no differences in erroneous orders with PoliCare CDSS (Kappa value 1.0). PoliCare CDSS can easily be integrated into the workflow for improving the overall efficiency and better adherence to evidence-based guidelines. Los programas de cribado de cáncer colorrectal (CCR) generan un gran número de colonoscopias de seguimiento. Un sistema de soporte a la decisión clínica basado en el conocimiento (K-CDSS) es una tecnología que contiene reglas clínicas y asociaciones de datos que ayudan en la tarea de toma de decisiones clínicas. El objetivo fue desarrollar un K-CDSS para el manejo de los pacientes de cribado de CCR, y evaluar su eficacia. Recolectamos información de 48 variables de registros de colonoscopia. Mediante el software DILEMMA ( https://www.dilemasolution.com ) diseñamos un prototipo de K-CDSS (PoliCare CDSS), para proporcionar recomendaciones personalizadas, combinando los datos de los pacientes y las recomendaciones de las guías actuales. La exactitud de las reglas se verificó mediante cuatro escenarios (colonoscopia normal, lesiones diferentes a pólipos, adenomas no avanzados y adenomas avanzados). Se estudió el grado de concordancia entre las valoraciones clínicas realizadas por médicos expertos y enfermeros equipados con PoliCare CDSS. Dos expertos confirmaron una correlación entre las pautas y las recomendaciones de PoliCare. Se incluyeron 56 casos consecutivos del programa de cribado (62,8 años; rango 53-71). Los resultados de la colonoscopia fueron: ausencia de lesiones de colon (n = 7, 12,5%), lesiones en el colon que no son pólipos (n = 3, 5,4%) y pólipos de colon resecados (n = 46, 82,1%; resección R0 del 100%). Los pacientes con pólipos resecados presentaron adenoma no avanzado (n = 21, 45,6%) o lesiones avanzadas (n = 25, 54,4%). No hubo diferencias en recomendaciones erróneas con PoliCare CDSS (valor Kappa 1.0). PoliCare CDSS se puede integrar fácilmente en el flujo de trabajo de una unidad de endoscopia digestiva.

Barriers toward Colorectal Cancer Screening among Public in Saudi Arabia

Colorectal cancer incidence has increased significantly in Saudi Arabia in the last few years. Although protocols and guidelines for colorectal screening programs had been established to start at age 45, adherence to screening remains low. This review aims to identify the potential barriers to participating in the screening program among the public aged over forty-five in Saudi Arabia. A significant lack of awareness about colorectal cancer and screening programs had found among Saudi Arabia's public (SA). The acceptance rate significantly increased due to health care provider recommendations. Knowledge about colorectal cancer and screening program and outcome should be raised among the public through campaigns and physicians by training established for primary health care providers regarding screening programs recommendations.

Colorectal Screening Program in Northern Portugal: First Findings

In Portugal, a colorectal cancer screening program based on faecal immunochemical test followed by colonoscopy was shown to be cost-effective for individuals between 50 and 74 years old. We report the first findings of the implementation of a population-based program In Northern Portugal. In the pilot phase, eligible subjects were allocated either to a direct mailing invitation or to primary care centers. In the first year of program implementation, we assessed the uptake rate, the faecal immunochemical test -positivity rate, the diagnostic yield of advanced neoplasia, and the quality parameters for post-faecal immunochemical test + colonoscopy. We invited 100 501 eligible subjects (49% male with a median age of 55 years). Of these, 5228 participated in the pilot phase and 95 273 participated in the first year of the program. In the first year of the program, the adherence was 29%, with a positivity rate of 5% and a 60% compliance to colonoscopy. The faecal immunochemical test-detection rate of advanced neoplasia was 0.35/1000 subjects, and the positive predictive value at post- faecal immunochemical test + colonoscopy was 44% and 2% for advanced adenoma and invasive cancer, respectively. No major adverse events were reported after colonoscopy. The suboptimal adherence to faecal immunochemical test and post-faecal immunochemical test + colonoscopy remains the most urgent step to be addressed. A centralized invitation system based on direct mailing was feasible and both colonoscopy quality and diagnostic yield were adequate antecipating the success of the programme.

Prevalence of adenomatous polyposis in a fecal immunochemical test-based colorectal cancer screening program and risk of advanced neoplasia during follow-up.

We retrospectively included all FIT-positive participants with ≥ 10 adenomas at index colonoscopy between 2010 and 2018. Surveillance colonoscopies were collected until 2019. Patients with inherited syndromes, serrated polyposis syndrome, total colectomy, or lacking surveillance data were excluded. The cumulative incidence of CRC and advanced neoplasia were analyzed by Kaplan-Meier analysis. Risk factors for metachronous advanced neoplasia were investigated by multivariable logistic regression analysis. 215 of 9582 participants (2.2 %) had ≥ 10 adenomas. Germline genetic testing was performed in 92 % of patients with ≥ 20 adenomas, identifying two inherited syndromes (3.3 %). The 3-year cumulative incidence of CRC and advanced neoplasia were 1 % and 16 %, respectively. In 39 patients (24.2 %), no polyps were found on first surveillance colonoscopy. The presence of an advanced adenoma was independently associated with a higher risk of advanced neoplasia at first surveillance colonoscopy (odds ratio 3.91, 95 %CI 1.12-13.62; P = 0.03). Beyond the first surveillance colonoscopy, the risk of metachronous advanced neoplasia was lower. The prevalence of ≥ 10 adenomas in a FIT-based CRC screening program was 2.2 %; a small proportion of inherited syndromes were detected, even amongst those with ≥ 20 adenomas. A low rate of post-colonoscopy CRC was observed and the risk of advanced neoplasia beyond the first surveillance colonoscopy tended to progressively decrease throughout successive follow-ups.

Association between body mass index and colorectal adenomas: Findings from a case-control study in Vietnam.

Colorectal cancer is a leading cancer worldwide and in Vietnam. Adenomas (adenomatous polyps) is an important precursor of colorectal cancer. There is currently no study to determine the modifiable risk factors for colorectal adenomas, including body mass index (BMI) in Vietnam. We conducted an individually matched case-control study of 1149 colorectal adenomas and 1145 controls in a large-scale colorectal screening program involving 103 542 individuals aged 40-75 years old in Hanoi, Vietnam. Conditional logistic regression was used to evaluate the association between BMI and colorectal adenomas prevalence, after controlling for potential confounders. Overall, comparing to normal weight (ie, 18.5-22.9kg/m2 ), underweight (ie, BMI < 18.5) was associated with a non-statistically significant increased prevalence of colorectal adenomas (odd ratio [OR]=1.29 and 95% confident interval [CI]: 0.88-1.87). This association became significant among male (OR=1.98, 95% CI: 1.20-3.27), male who were ever smokers (OR=2.59, 95% CI: 1.33-5.03), nonregular exercise (OR=2.44, 95% CI: 1.26-4.73) and individuals with cardiometabolic disorders (OR=3.46, 95% CI: 1.19-10.00). The association between underweight and colorectal adenomas did not vary by smoking status, drinking status, family history of cancer, adenomas types or cardiometabolic disorders. No association was observed among obese individuals (BMI ≥ 25). In the population with low prevalence of obesity, we found that the association between BMI and colorectal adenomas followed a reversed J-shape that underweight was associated with increased prevalence. Further studies are, therefore, warranted to replicate our results and to investigate the biologic mechanism the effect of underweight on colorectal adenomas prevalence.

Development of knowledge-based clinical decision support system for patients included in colorectal screening program

Background & aimsColorectal (CRC) screening programs represent a large volume of procedures that need a follow-up endoscopy. A knowledge-based clinical decision support system (K-CDSS) is a technology which contains clinical rules and associations of compiled data that assist with clinical decision-making tasks. We develop a K-CDSS for management of patients included in CRC screening and surveillance of colorectal polyps. MethodsWe collected information on 48 variables from hospital colonoscopy records. Using DILEMMA Solutions Platform © (https://www.dilemasolution.com) we designed a prototype K-CDSS (PoliCare CDSS), to provide tailored recommendations by combining patients data and current guidelines recommendations. The accuracy of rules was verified using four scenarios (normal colonoscopy, lesions different than polyps, non-advanced adenomas and advanced adenomas). We studied the degree of agreement between the clinical assessments made by expert doctors and nurses equipped with PoliCare CDSS. Two experts confirmed a correlation between guidelines and PoliCare recommendations. Results56 consecutive endoscopy cases from colorectal screening program were included (62.8 years; range 53-71). Colonoscopy results were: absence of colon lesions (n=7, 12.5%), lesions in the colon that are not polyps (n=3, 5.4%) and resected colonic polyps (n=46, 82.1%; 100% R0 resection). Patients with resected polyps presented non-advanced adenoma (n=21, 45.6%) or advanced lesions (n=25, 54.4%). There were no differences in erroneous orders with PoliCare CDSS (Kappa value 1.0). ConclusionsPoliCare CDSS can easily be integrated into the workflow for improving the overall efficiency and better adherence to evidence-based guidelines.