Colorectal Cancer Screening in Free Clinics: A Systematic Review.

OBJECTIVE: There are significant inequities in colorectal cancer (CRC) screening and outcomes. Via literature review, we assessed CRC screening rates for the vulnerable populations served by free clinics. METHODS: A systematic review was conducted for publications on CRC screening in free clinics. Outcomes included CRC screening characteristics, population demographics, and limitations. A methodological quality assessment was completed. RESULTS: Out of 63 references, six studies were included, representing 8,844 participants. Black or Hispanic participants were the plurality in all but one study. All participants were uninsured. Median CRC screening rate was 48.4% (range 6.6-78.9%). Screening methods included colonoscopy, fecal occult blood test, flexible sigmoidoscopy, and fecal immunochemical test. Clinics offering only one screening method had a mean screening rate of 7.2% while those with multiple methods had a screening rate of 65.4%. CONCLUSION: Access to multiple CRC screening modalities correlates with higher screening rates in free clinics. More work is needed to increase CRC screening in free clinics.

Faecal Immunochemical Test (FIT) Sensitivity; A Five Year Audit.

Introduction: Colorectal cancer has a high prevalence and mortality rate in the United Kingdom. Cancerous colorectal lesions often bleed into the gastrointestinal lumen. The faecal immunochemical test (FIT) detects haemoglobin (Hb) in the faeces of patients and is used as a first line test in the diagnosis of colorectal cancer. Materials and Methods: A retrospective audit of all FIT performed and all colorectal cancers diagnosed in the Hull and East Riding of Yorkshire counties of the United Kingdom (population approximately 609,300) between 2018 and 2022 was conducted. FIT were performed using a HM-JACKarc analyser from Kyowa medical. The predominant symptom suggestive of colorectal cancer which prompted the FIT was recorded. Colorectal cancer was diagnosed using the gold standard of histological biopsy following colonoscopy. Results: Between 2018 and 2022, 56,202 FIT were performed on symptomatic patients. Follow on testing identified 1,511 with colorectal cancer. Of these people, only 450 people with a confirmed colorectal cancer had a FIT within the 12 months preceding their diagnosis. Of these 450 FIT results, 36 had a concentration of <10 µg/g and may be considered to be a false negative. The sensitivity of FIT in the patients identified was 92.00%. The most common reason stated by the clinician for a FIT being performed in patients with colorectal cancer was a change in bowel habits, followed by iron deficient anaemia. The number of patients diagnosed with colorectal cancer decreased in 2020, but increased significantly in 2021. Discussion: This study shows that 8.00% of people diagnosed with colorectal cancer in the Hull and East Riding of Yorkshire regions had a negative FIT. This study also shows that the SARS-CoV-2 pandemic affected the number of people diagnosed with colorectal cancer, and therefore skews the prevalence and pre-test probability of a positive test. There are many reasons why a FIT could produce a false negative result, the most likely being biological factors affecting the stability of haemoglobin within the gastrointestinal tract, or pre-analytical factors influencing faecal sampling preventing the detection of haemoglobin. Some colorectal lesions do not protrude into the gastrointestinal lumen and are less likely to bleed. Conclusion: This is the first study showing data from outside of a structured clinical trial and provides the largest study to date showing the sensitivity of FIT in a routine clinical setting. This study also provides evidence for the impact COVID-19 had on the rate of colorectal cancer diagnosis.

Population-level impact of the BMJ Rapid Recommendation for colorectal cancer screening: a microsimulation analysis.

OBJECTIVE: In 2019, a BMJ Rapid Recommendation advised against colorectal cancer (CRC) screening for adults with a predicted 15-year CRC risk below 3%. Using Switzerland as a case study, we estimated the population-level impact of this recommendation. DESIGN: We predicted the CRC risk of all respondents to the population-based Swiss Health Survey. We derived the distribution of risk-based screening start age, assuming predicted risk was calculated every 5 years between ages 25 and 70 and screening started when this risk exceeded 3%. Next, the MISCAN-Colon microsimulation model evaluated biennial faecal immunochemical test (FIT) screening with this risk-based start age. As a comparison, we simulated screening initiation based on age and sex. RESULTS: Starting screening only when predicted risk exceeded 3% meant 82% of women and 90% of men would not start screening before age 65 and 60, respectively. This would require 43%-57% fewer tests, result in 8%-16% fewer CRC deaths prevented and yield 19%-33% fewer lifeyears gained compared with screening from age 50. Screening women from age 65 and men from age 60 had a similar impact as screening only when predicted risk exceeded 3%. CONCLUSION: With the recommended risk prediction tool, the population impact of the BMJ Rapid Recommendation would be similar to screening initiation based on age and sex only. It would delay screening initiation by 10-15 years. Although halving the screening burdens, screening benefits would be reduced substantially compared with screening initiation at age 50. This suggests that the 3% risk threshold to start CRC screening might be too high.

Barriers and facilitators of implementing a multicomponent intervention to improve faecal immunochemical test (FIT) colorectal cancer screening in primary care clinics, Alberta.

BACKGROUND AND OBJECTIVE: Colorectal cancer (CRC) screening is effective at reducing the incidence and mortality of CRC. To address suboptimal CRC screening rates, a faecal immunochemical test (FIT) multicomponent intervention was piloted in four urban multidisciplinary primary care clinics in Alberta from September 2021 to April 2022. The interventions included in-clinic distribution of FIT kits, along with FIT-related patient education and follow-up. This study explored barriers and facilitators to implementing the intervention in four primary clinics using the Consolidated Framework for Implementation Research (CFIR). METHODS: In-depth qualitative semistructured key informant interviews, guided by the CFIR, were conducted with 14 participants to understand barriers and facilitators of the FIT intervention implementation. Key informants were physicians, quality improvement facilitators and clinical staff. Interviews were analysed following an inductive-deductive approach. Implementation barriers and facilitators were organised and interpreted using the CFIR to facilitate the identification of strategies to mitigate barriers and leverage facilitators for implementation at the clinic level. RESULTS: Key implementation facilitators reported by participants were patient perceived needs being met; the clinics' readiness to implement FIT, including staff's motivation, skills, knowledge, and resources to implement; intervention characteristics-evidence-based, adaptable and compatible with existing workflows; regular staff communications; and use of the electronic medical record (EMR) system. Key barriers to implementation were patient's limited awareness of FIT screening for CRC and discomfort with stool sample collection; the impacts of COVID-19 (patients missed appointment, staff coordination and communication were limited due to remote work); and limited clinic capacity (knowledge and skills using EMR system, staff turnover and shortage). CONCLUSION: Findings from the study facilitate the refinement and adaption of future FIT intervention implementation. Future research will explore implementation barriers and facilitators in rural settings and from patients' perspectives to enhance the spread and scale of the intervention.

Costs and Projected Effect of a Federally Qualified Health Center-Based Mailed Colorectal Cancer Screening Program in Texas.

Introduction: Mailed stool testing for colorectal cancer (CRC) may improve screening uptake and reduce the incidence and mortality of CRC, especially among patients at federally qualified health centers (FQHCs). To expand screening programs it is important to identify cost-effective approaches. Methods: We developed a decision-analytic model to estimate the cost, effects on screening and patient outcomes (CRCs detected, CRCs prevented, CRC deaths prevented), and cost-effectiveness of implementing a state-wide mailed stool testing program over 5 years among unscreened, age-eligible (aged 50-75 y) patients at FQHCs in Texas. We compared various outreach strategies and organizational structures (centralized, regional, or a hybrid). We used data from our existing regional mailed stool testing program and recent systematic reviews to set parameters for the model. Costs included start-up and ongoing activities and were estimated in 2022 US dollars from the perspective of a hypothetical third-party payer. Cost-effectiveness was assessed by using both incremental and average cost-effectiveness ratios. Results: Using either a statewide centralized or hybrid organizational configuration to mail stool tests to newly eligible FQHC patients and patients who have responded at least once since program inception is likely to result in the best use of resources over 5 years, enabling more than 110,000 additional screens, detecting an incremental 181 to 194 CRCs, preventing 91 to 98 CRCs, and averting 46 to 50 CRC deaths, at a cost of $10 million to $11 million compared with no program. Conclusions: A statewide mailed stool testing program for FQHC patients can be implemented at reasonable cost with considerable effects on CRC screening outcomes, especially when its structure maximizes program efficiency while maintaining effectiveness.

Screening for Colorectal Cancer.

Colorectal cancer remains the third leading cause of cancer death in the United States. Colorectal cancer screening allows for prevention and early detection of precancerous and cancerous lesions, and screening has been shown to be effective in preventing colorectal cancer deaths. Screening recommendations vary by patient risk profile. A variety of screening modalities exist.

Estimated impact and value of blood-based colorectal cancer screening at varied adherence compared with stool-based screening.

OBJECTIVE: This analysis estimated the outcomes of triennial blood-based colorectal cancer (CRC) screening at various adherence, including perfect adherence, compared with triennial multi-target stool DNA (mt-sDNA) screening at the reported real-world adherence rate. METHODS: The validated CRC-AIM model simulated a US cohort of average-risk individuals receiving triennial screening with mt-sDNA or blood-based test from ages 45 to 75 years. Modeled specificity and sensitivity were based on reported data. Adherence was set at a real-world rate of 65.6% for mt-sDNA and at 65.6%, relative 10% incremental increases from 65.6%, or 100% for the blood-based test. Costs of mt-sDNA and the blood-based test were based on prices for clinically available tests ($508.87 and $895, respectively). Value-based pricing was estimated at a willingness-to-pay threshold of $100,000. RESULTS: Both tests resulted in life-years gained (LYG), reduced CRC cases, and reduced deaths versus no screening. With adherence for mt-sDNA set at 65.6% and for blood-based test set at 100%, mt-sDNA resulted in 30% more LYG, 52% more averted CRC cases, and 32% more averted CRC deaths. At reported sensitivity and specificity rates, mt-sDNA at 65.6% adherence dominates (is more effective and less costly) the blood-based test at any adherence. There was no price at which triennial screening with the blood-based test at any adherence was cost-effective compared with mt-sDNA at 65.6% adherence. CONCLUSIONS: Triennial screening with mt-sDNA resulted in better clinical outcomes at a lower cost compared with the modeled blood-based test even at perfect adherence, supporting application of blood-based tests only as a secondary screening option.

Blood-based colorectal cancer screening has lower diagnostic accuracy, lower clinical and health outcomes, and is more expensive than mt-sDNA, even with perfect blood-based screening participation. Although better than no screening at all, blood-based testing is unlikely to exceed performance of stool-based assessment unless a blood-based test is able to meaningfully detect precancerous growths.

Quantified trends in provider reimbursement and utilization volume in colorectal cancer screenings: analysis of Medicare claims from 2000 to 2019.

AIM: Colorectal cancer (CRC) screening rates in the United States remain persistently below guideline targets, partly due to suboptimal patient utilization and provider reimbursement. To guide long-term national utilization estimates and set reasonable screening adherence targets, this study aimed to quantify trends in utilization of and reimbursement for CRC screenings using Medicare claims. METHOD: Inflation-adjusted reimbursements and utilization volume associated with each CRC screening code were abstracted from Medicare claims between 2000 and 2019. Screenings, screenings/100 000 enrolees and reimbursement/screening were analysed with linear regression and compared with the equality of slopes tests. Average reimbursement per screening was compared using analysis of variance with Dunnett's T3 multiple comparisons test. RESULTS: The growth rate of multitarget stool DNA tests (mt-sDNA)/100 000 was the highest at 170.4 screenings/year (R2 = 0.99, p ≤ 0.001), while that of faecal occult blood tests/100 000 was the lowest at -446.4 screenings/year (R2 = 0.90, p ≤ 0.001) (p ≤ 0.001). Provider reimbursements averaged $546.95 (95% CI $520.12-$573.78) per mt-sDNA screening, significantly higher than reimbursements for all invasive screenings. Only FOBTs significantly increased in reimbursement per screening at $0.62/year (R2 = 0.91, p ≤ 0.001). CONCLUSION: We derived forecastable trend numbers for utilization and provider reimbursement. Faecal immunochemical tests/100 000 and mt-sDNA screenings/100 000 increased most rapidly during the entire study period. The number of nearly all invasive screenings/100 000 decreased rapidly; the number of colonoscopies/100 000 increased slightly, probably due to superior diagnostic strength. These trends indicate the that replacement of other invasive modalities with accessible noninvasive screenings will account for much of future screening behaviour and thus reductions in CRC incidence and mortality, especially given providers' reimbursement incentive to screen average-risk patients with stool-based tests.

Trends in Colorectal Cancer Screening from the National Health Interview Survey: Analysis of the Impact of Different Modalities on Overall Screening Rates.

Colorectal cancer is the second leading cause of cancer-related mortality in adults in the United States. Despite compelling evidence of improved outcomes in colorectal cancer, screening rates are not optimal. This study aimed to characterize colorectal cancer screening trends over the last two decades and assess the impact of various screening modalities on overall colorectal cancer screening rates. Using National Health Interview Survey data from 2005 to 2021, we examined colorectal cancer screening [colonoscopy, multitarget stool DNA (mt-sDNA), fecal occult blood test (FOBT)/fecal immunochemical test, sigmoidoscopy, CT colonography] rates among adults ages 50-75 years (n = 85,571). A pseudo-time-series cross-sectional (pseudo-TSCS) analysis was conducted including a random effects generalized least squares regression model to estimate the relative impact of each modality on changes in colorectal cancer screening rates. Among 50 to 75 year olds, the estimated colorectal cancer screening rate increased from 47.7% in 2005 to 69.9% in 2021, with the largest increase between 2005 and 2010 (47.7%-60.7%). Rates subsequently plateaued until 2015 but increased from 63.5% in 2015 to 69.9% in 2018. This was primarily driven by the increased use of mt-sDNA (2.5% in 2018 to 6.6% in 2021). Pseudo-TSCS analysis results showed that mt-sDNA contributed substantially to the increase in overall screening rates (77.3%; P < 0.0001) between 2018 and 2021. While colorectal cancer screening rates increased from 2005 to 2021, they remain below the 80% goal. The introduction of mt-sDNA, a noninvasive screening test may have improved overall rates. Sustained efforts are required to further increase screening rates to improve patient outcomes and offering a range of screening options is likely to contribute to achieving this goal. PREVENTION RELEVANCE: This retrospective study highlights the importance of convenient stool-based colorectal cancer screening options to achieve the national goal of 80% for overall colorectal cancer screening rates. Empowering screening-eligible individuals with a choice for their colorectal cancer screening tests is imperative.

Real-world data evaluating Guy's rapid diagnostic clinic as an alternate pathway for patients with FIT levels below 10.

OBJECTIVE: To analyse the effectiveness of rapid diagnostic clinics (RDCs) as an alternative pathway for patients with concerning symptoms and a faecal immunochemical test (FIT) result <10. Our primary endpoint was rate of colorectal cancer (CRC) detection. Second endpoints were rates of other cancers and gastrointestinal (GI) serious benign conditions. Finally, we analysed the specific pathway followed by FIT <10 patients with cancer at Guy's and St Thomas NHS Foundation Trust (GSTT) RDC. DESIGN: A retrospective and prospective cohort study. SETTING: GSTT RDC, one of England's largest single-centre RDCs. Sociodemographic and clinical characteristics of FIT <10 patients were analysed descriptively. PARTICIPANTS: Patients with an FIT result <10, seen at GSTT RDC between 1 January 2020 and 5 May 2023. RESULTS: A total of 1299 patients with an FIT<10 were seen at GSTT RDC between January 2020 and May 2023. Of these, 66% (n=861) reported weight loss, 62% (n=805) pain, 37% (n=481) fatigue, 34% (n=444) were anaemic and 23% (n=301) had nausea and vomiting. Among these patients, 7% (n=88) received a cancer diagnosis, 36% (n=462) were identified as having a serious benign condition. Within the patients with cancer, 9% (n=8) were diagnosed with CRC. Among patients with serious benign conditions, 7% (n=31) were referred to colorectal, hepatopancreatobiliary, or upper GI specialists. CONCLUSION: This study demonstrates the effectiveness of RDCs as an alternate pathway for FIT <10 patients with ongoing clinical concerns. These results contribute to enhancing patient care and optimising resource allocation within the healthcare system.

Infectious etiology and indicators of malabsorption or intestinal injury in childhood diarrhea. / Etiología infecciosa e indicadores de malabsorción o daño intestinal en diarrea infantil

INTRODUCTION: The multifactorial etiology of gastroenteritis emphasizes the need for different laboratory methods to identify or exclude infectious agents and evaluate the severity of diarrheal disease. OBJECTIVE: To diagnose the infectious etiology in diarrheic children and to evaluate some fecal markers associated with intestinal integrity. MATERIALS AND METHODS: The study group comprised 45 children with diarrheal disease, tested for enteropathogens and malabsorption markers, and 76 children whose feces were used for fat evaluation by the traditional and acid steatocrit tests. RESULTS: We observed acute diarrhea in 80% of the children and persistent diarrhea in 20%. Of the diarrheic individuals analyzed, 40% were positive for enteropathogens, with rotavirus (13.3%) and Giardia duodenalis (11.1%) the most frequently diagnosed. Among the infected patients, occult blood was more evident in those carrying pathogenic bacteria (40%) and enteroviruses (40%), while steatorrhea was observed in infections by the protozoa G. duodenalis (35.7%). Children with diarrhea excreted significantly more lipids in feces than non-diarrheic children, as determined by the traditional (p<0.0003) and acid steatocrit (p<0.0001) methods. Moreover, the acid steatocrit method detected 16.7% more fecal fat than the traditional method. CONCLUSIONS: Childhood diarrhea can lead to increasingly severe nutrient deficiencies. Steatorrhea is the hallmark of malabsorption, and a stool test, such as the acid steatocrit, can be routinely used as a laboratory tool for the semi-quantitative evaluation of fat malabsorption in diarrheic children.

Introducción. La etiología multifactorial de la gastroenteritis enfatiza la necesidad de usar diferentes métodos de laboratorio para identificar o excluir agentes infecciosos y evaluar la gravedad de la enfermedad diarreica. Objetivo. Diagnosticar la etiología infecciosa de la diarrea en niños y evaluar algunos marcadores fecales asociados con la integridad intestinal. Materiales y métodos. Se estudiaron 45 niños con enfermedad diarreica, en los cuales se evaluaron la presencia de enteropatógenos y los marcadores de malabsorción. Se analizaron las muestras fecales de 76 niños, mediante las pruebas de esteatocrito tradicional y esteatocrito ácido, para la cuantificación de la grasa. Resultados. Se observó diarrea aguda en el 80 % de los niños y diarrea persistente en el 20 %. De los individuos con diarrea, el 40 % fue positivo para enteropatógenos; los más diagnosticados fueron rotavirus (13,3 %) y Giardia duodenalis (11,1 %). Entre los pacientes infectados, la sangre oculta fue más evidente en aquellos portadores de bacterias patógenas (40 %) o enterovirus (40%), mientras que la esteatorrea se observó en infecciones por el protozoo G. duodenalis (35,7 %). Los niños con diarrea excretaron significativamente más lípidos en las heces que aquellos sin diarrea, según lo determinado por los métodos de esteatocrito tradicional (p<0,0003) y esteatocrito ácido (p<0,0001). Conclusiones. La diarrea infantil puede provocar deficiencias graves de nutrientes. La esteatorrea es distintiva de la malabsorción intestinal y puede detectarse mediante la estimación del esteatocrito ácido. Esta prueba podría utilizarse de forma rutinaria como una herramienta de laboratorio para la evaluación semicuantitativa de la malabsorción de grasas en niños con diarrea.

Screening for Colorectal Cancer.

Colorectal cancer (CRC) is the second leading cause of cancer death. Screening has been proven to reduce both cancer incidence and cancer-related mortality. Various screening tests are available, each with their own advantages and disadvantages and varying levels of evidence to support their use. Clinicians should offer CRC screening to average-risk persons aged 50 to 75 years; starting screening at age 45 years remains controversial. Screening may be beneficial in select persons aged 76 to 85 years, based on their overall health and screening history. Offering a choice of screening tests or sequentially offering an alternate test for those who do not complete screening can significantly increase participation.

On repeated diagnostic testing in screening for a medical condition: How often should the diagnostic test be repeated?

In screening large populations a diagnostic test is frequently used repeatedly. An example is screening for bowel cancer using the fecal occult blood test (FOBT) on several occasions such as at 3 or 6 days. The question that is addressed here is how often should we repeat a diagnostic test when screening for a specific medical condition. Sensitivity is often used as a performance measure of a diagnostic test and is considered here for the individual application of the diagnostic test as well as for the overall screening procedure. The latter can involve an increasingly large number of repeated applications, but how many are sufficient? We demonstrate the issues involved in answering this question using real data on bowel cancer at St Vincents Hospital in Sydney. As data are only available for those testing positive at least once, an appropriate modeling technique is developed on the basis of the zero-truncated binomial distribution which allows for population heterogeneity. The latter is modeled using discrete nonparametric maximum likelihood. If we wish to achieve an overall sensitivity of 90%, the FOBT should be repeated for 2 weeks instead of the 1 week that was used at the time of the survey. A simulation study also shows consistency in the sense that bias and standard deviation for the estimated sensitivity decrease with an increasing number of repeated occasions as well as with increasing sample size.

Engaging with Rural Communities for Colorectal Cancer Screening Outreach Using Modified Boot Camp Translation.

BACKGROUND: Colorectal cancer (CRC) incidence and mortality are disproportionately high among rural residents and Medicaid enrollees. OBJECTIVES: To address disparities, we used a modified community engagement approach, Boot Camp Translation (BCT). Research partners, an advisory board, and the rural community informed messaging about CRC outreach and a mailed fecal immunochemical test program. METHODS: Eligible rural patients (English-speaking and ages 50-74) and clinic staff involved in patient outreach participated in a BCT conducted virtually over two months. We applied qualitative analysis to BCT transcripts and field notes. RESULTS: Key themes included: the importance of directly communicating about the seriousness of cancer, leveraging close clinic-patient relationships, and communicating the test safety, ease, and low cost. CONCLUSIONS: Using a modified version of BCT delivered in a virtual format, we were able to successfully capture community input to adapt a CRC outreach program for use in rural settings. Program materials will be tested during a pragmatic trial to address rural CRC screening disparities.

[Barriers and facilitators of colorectal cancer screening access]. / Barreras y facilitadores del acceso al tamizaje de cáncer colorrectal.

INTRODUCTION: Colorectal cancer (CRC) is a global health problem. In the public sector of Bahía Blanca, CRC screening is opportunistic, through the request of fecal occult blood test (FOBT). The objective of this study is to describe access to CRC screening for the population with exclusive public coverage residing in the programmatic area 2 of the city between 2019 and 2021, and to identify the barriers and facilitators that determine it. METHODS: The annual and cumulative usage rate was estimated based on the number of patients who requested FOBT. The barriers and facilitators were studied through 41 semi-structured individual interviews to healthcare staff from the area, the Municipal Hospital, Health Secretariat and users/non-users of the system. RESULTS: The cumulative usage rate of FOBT during the period was less than 5%. Among the perceived barriers to screening, we found: the difficulties in accessing more complex studies for patients with positive FOBT, the lack of population awareness and perception of CRC as a health problem, the low adherence of professionals to guidelines. The territoriality and link of health centers with the population, as well as the willingness of users and professionals to incorporate screening, emerge as facilitators. CONCLUSION: The identification of barriers and facilitators will allow the design of context-adapted strategies that will strengthen screening in the future.

Introducción: El cáncer colorrectal (CCR) es un problema de salud a nivel global. En el sector público de Bahía Blanca, el tamizaje de CCR es oportunista, por solicitud de sangre oculta en materia fecal (SOMF). El objetivo de este trabajo es describir el acceso al tamizaje de CCR de la población con cobertura pública exclusiva que reside en el área programática 2 de la ciudad entre 2019 y 2021, y relevar las barreras y facilitadores que lo determinan. Métodos: Se estimó la tasa de uso anual y acumulada de SOMF. Las barreras y facilitadores se relevaron a través de 41 entrevistas individuales semi-estructuradas al personal de salud del área programática, el Hospital Municipal, Secretaría de Salud y usuarios/no usuarios del sistema. Resultados: La tasa acumulada de uso de SOMF en el período fue 4.8%. Entre las barreras al tamizaje percibidas se destacan: la dificultad en el acceso a estudios de mayor complejidad para pacientes con SOMF+, el desconocimiento y falta de percepción del CCR como un problema de salud por parte de la población y la baja adherencia de los profesionales a los lineamientos. La territorialidad y el vínculo de los centros de salud con la población, y la predisposición de usuarios y profesionales a incorporar el tamizaje surgen como facilitadores del mismo. Conclusiones: El relevamiento de las barreras orientará el diseño de estrategias adaptadas al contexto que permitan en el futuro reforzar el tamizaje.