Colorectal cancer screening: a global overview of existing programmes

Interval cancer risk after the upper age limit of screening has been reached: Informing risk stratification in FIT-based colorectal cancer screening

Upper age limits are currently fixed for all fecal immunochemical test (FIT)-based colorectal cancer (CRC) screening programs. A risk-stratified upper age limit may be beneficial. Therefore, we assessed differences in interval CRC risk among individuals who had reached the upper age limit of screening (75 years). Individuals with a negative FIT (<47 μg Hb/g feces) in the final round of the Dutch CRC screening program were selected from the national screening database and linked to the national cancer registry to identify CRCs diagnosed within 24 months (interval CRCs). Survival analyses assessed whether sex and last fecal hemoglobin (f-Hb) concentration were associated with interval CRC risk. A multivariable logistic regression assessed whether sex, last f-Hb concentration and screening round were associated with stage distribution (early vs. late). Last f-Hb concentrations were considered detectable when they were >0 μg Hb/g feces. Among 305,761 individuals with a complete follow-up (24 months), 661 were diagnosed with interval CRC (21.6 per 10,000 negative FITs). Individuals with detectable f-Hb (15%) were 5 times more likely to be diagnosed with interval CRC than those without (HR 4.87, 95%CI: 4.19-5.65). Moreover, their cancers were more often detected at a late stage compared to individuals without detectable f-Hb (OR 1.45, 95%CI: 1.06-2.01). Our results show that interval CRC risk among individuals aged ≥75 differs substantially by last f-Hb concentration, indicating a uniform age to stop screening is suboptimal. Future research, taking into account multiple screening rounds and FIT results, should determine the optimal risk-stratified screening strategy.

Spatial and temporal dynamic of colorectal cancer mortality in Brazil: A nationwide population-based study of four decades (1980-2021)

BACKGROUND

Regardless of being preventable through screening strategies and prompt diagnosis, deaths from colorectal cancer (CRC) still represent a serious public health concern in Brazil, with more than 20 thousand deaths annually. Herein, we aimed to assess the temporal trends and spatiotemporal patterns of CRC mortality in all Brazilian states.

METHODS

An ecological study using temporal and spatial analysis techniques on deaths due to CRC as the underlying cause in Brazil from 1980 to 2021 was conducted. Death certificate and population data were provided by the Department of Informatics of the Unified Health System (DATASUS) and by the Brazilian Institute of Geography and Statistics (IBGE), respectively.

RESULTS

A total of 395,782 deaths from CRC were recorded in this period and most of them were in female (205,479; 51.92 %), ≥ 65 years old (233,059; 58.89 %), diagnosed with malignant neoplasm of the colon (212,277; 53.63 %), with 1-7 years of education (157.564; 39.81 %), married (192.276; 48.58 %), hospital as place of death (331.393; 83.73 %) and white (212.666; 65.07 %). Moreover, there was an increasing temporal trend in the Northeast region (APC: 2.6; p < 0.05), men (APC: 1.5; p < 0.05) and 45-64 years old (APC: 1.2; p < 0.05). Also, the spatial analysis showed positive spatial autocorrelation in all periods, with the South and Southeast regions presenting the highest concentration of high-risk clusters CRC deaths. Nevertheless, high-risk clusters were also observed in capitals and municipalities in metropolitan regions in the Northeast region.

CONCLUSIONS

In general, a temporal and spatial expansion of CRC mortality has been observed in Brazil over the last few decades.

Family History of Colorectal Cancer and the Risk of Colorectal Neoplasia: A Systematic Review and Meta-Analysis

INTRODUCTION

Although there is enough pooled evidence supporting the positive association between family history of colorectal cancer (CRC) in first-degree relatives (FDRs) and the risk of CRC, synthesized data on its association with the risk of other colorectal neoplasia are lacking. Therefore, we aimed to systematically assess this issue.

METHODS

We searched PubMed, Web of Science, and Embase from database inception through May 9, 2024, to identify observational studies investigating the association between family history of CRC in FDRs and the risk of colorectal neoplasia (excepting CRC). Adenoma, nonadvanced adenoma (NAA), advanced adenoma (AA), and advanced neoplasia (AN) were further chosen as main outcomes because of data availability. Random-effects model was used for data synthesis. Subgroup meta-analyses were performed to evaluate the robustness of results.

RESULTS

Of 5,172 initial records screened, 75 studies (with 931,515 participants) were identified for analysis. Family history of CRC in FDRs was associated with increased risk of adenoma (pooled odds ratio [OR] 1.67, 95% confidence interval [CI] 1.46-1.91), NAA (pooled OR 1.35, 95% CI 1.21-1.51), AA (pooled OR 1.66, 95% CI 1.46-1.88), and AN (pooled OR 1.58, 95% CI 1.44-1.73). The positive associations persisted in all examined subgroups. The risk of adenoma (pooled OR 4.18, 95% CI 1.76-9.91), AA (pooled OR 2.42, 95% CI 1.72-3.40), and AN (pooled OR 2.00, 95% CI 1.68-2.38) was more evident among individuals with 2 or more affected FDRs.

DISCUSSION

Family history of CRC is associated with increased risk of adenoma, NAA, AA, and AN totally, and in all available subgroups. The findings further strengthen the necessity and importance of an intensified screening strategy for individuals with a positive family history of CRC, which is very useful for related health resource allocation and policymaking.

Fecal Hemoglobin Levels in Prior Negative Screening and Detection of Colorectal Neoplasia: A Dose-Response Meta-Analysis

BACKGROUND & AIMS

Prior studies have shown that individuals with fecal hemoglobin (f-Hb) concentrations just below the positivity cutoff have an increased colorectal cancer risk compared with those with no or low f-Hb. Understanding the dose-response association between f-Hb in a prior screening round and the detection of colorectal neoplasia is crucial for tailoring risk-based screening recommendations.

METHODS

We searched the literature to identify studies reporting the association between f-Hb in prior screening round and colorectal neoplasia detection in an average-risk population. Analysis involved a 2-stage approach using log-log regression models to assess dose-response relationships across studies, with effect sizes pooled using a random effects model. Heterogeneity was assessed by excluding individual studies in sensitivity analyses. Subgroup analyses examined variations in effects by outcome definitions and detection methods.

RESULTS

This systematic review and meta-analysis included 13 studies with 4,493,672 individuals. All studies demonstrated a positive association between f-Hb in prior screenings and colorectal neoplasia detection. Pooled analysis revealed that individuals with f-Hb concentrations of 5, 10, 20, and 40 μg/g had a 3-, 5-, 8-, and 13-fold higher risk of colorectal neoplasia, respectively, compared with individuals with 0 μg/g. Although significant heterogeneity (I2 = 97.5%, P < .001) was observed, sensitivity analyses confirmed the consistency of findings. Subgroup analyses indicated that f-Hb concentrations from previous negative tests were especially predictive of advanced neoplasia in subsequent screenings.

CONCLUSIONS

Our findings suggest that the risk of detecting colorectal neoplasia increases with prior f-Hb concentrations in negative tests, supporting the development of risk-stratified screening strategies based on these concentrations.

Analytical evaluation of eight qualitative FIT for haemoglobin products, for professional use in the UK

OBJECTIVES

Qualitative faecal immunochemical tests for haemoglobin (FIT), for triaging for colorectal cancer investigations, are available for professional use. The aim was to evaluate these lateral flow tests. No previous analytical evaluations have been published.

METHODS

Analytical sensitivity (AS) was assessed using samples spanning manufacturers' quoted AS, concurrently with the quantitative OC-SENSOR PLEDIA, using Hb-spiked samples in manufacturers' buffer (n≥5; ≤9-99 ng Hb/mL buffer), Hb-spiked feces (n=6; <2-34 µg Hb/g feces) and natural feces (n=17; <2-82 μg/g); concentrations for 50 %/100 % Hb-detected were compared with quoted AS. Compatibility with two external quality assessment schemes (EQAS) (n=9; 3-96 μg/g) and prozone compared with manufacturers limits (n=9; 2,500-10,000,000 ng/mL) were tested. Ease-of-use by five healthcare personnel was assessed.

RESULTS

Seven products showed lower AS (ng/mL) than manufacturers quoted using Hb-spiked aqueous samples compared with OC-SENSOR, one was equivocal; six manufacturers quoted AS in µg/g, five showed lower AS using Hb-spiked feces. Results were similar but less consistent for natural feces. Result lines for low concentrations can be faint and open to interpretation. Results were consistent with manufacturers quoted prozone limits. Results were consistent for seven products for two EQAS. The ease-of-use was 68.5-85.6 %; products with lower scores could be improved with better instructions and sample bottles.

CONCLUSIONS

AS was lower for seven products (aqueous samples) and five products (aqueous/faecal samples) and prozone consistent with manufacturers expected concentrations, compared with OC-SENSOR. EQAS results were mostly consistent with expected results; products can be used by healthcare professionals, though some manufacturer improvements could be made.

Trends and Gaps in Colorectal Cancer Screening Research in the Arab World: A 16-Year Bibliometric Analysis (2007-2023)

Colorectal cancer (CRC) is a significant public health concern, ranking third in incidence and second in mortality worldwide. Despite rising CRC incidence rates in the Arab world, understanding of trends and patterns in CRC screening research remains limited. This study addresses this gap through a bibliometric analysis of CRC screening research in the Arab world from 2007 to 2023. We conducted an extensive literature search in Web of Science and Scopus databases, analyzing 124 articles using the Bibliometrix Package in R. Our findings revealed a 16.5% annual growth in research output, with significant increases from 2014 onwards. Saudi Arabia led in scientific production, followed by Lebanon, Jordan, and Egypt, while Qatar had the highest country production when adjusted for population size. Disparities in research output relative to the CRC burden were evident, especially in lower-resource countries. Three regional clusters were identified: Saudi Arabia, with strong collaborations with Canada and Egypt; a second cluster including Lebanon, UAE, Jordan, Qatar, Iraq, and Oman; and a third cluster featuring Morocco, with significant collaboration with France. Thematic analysis showed a focus on CRC screening awareness, barriers, and adherence but a lack of studies on implementation strategies and cost-effectiveness. This analysis highlights significant trends and gaps in CRC screening research in the Arab world, underscoring the need for increased investment in CRC research and screening initiatives to improve outcomes in the region.

Risk factors, prevention and screening of colorectal cancer: A rising problem

Colorectal cancer (CRC) is the third most commonly diagnosed cancer and the second leading cause of cancer death worldwide. The leading risk factors for CRC include male gender, age over 50, family history, obesity, tobacco smoking, alcohol consumption, and unhealthy diet. CRC screening methods vary considerably between countries and depend on incidence, economic resources and healthcare structure. Important aspects of screening include adherence, which can vary significantly across ethnic and socioeconomic groups. Basic concepts of CRC screening include pre-stratification of patients by identifying risk factors and then using fecal immunochemical test or guaiac-based fecal occult blood test and/or colonoscopy or radiologic imaging techniques. Technological capabilities for CRC screening are rapidly evolving and include stool DNA test, liquid biopsy, virtual colonography, and the use of artificial intelligence. A CRC prevention strategy should be comprehensive and include active patient education along with targeted implementation of screening.

Biomarkers of inflammation and colorectal cancer risk

Globally, colorectal malignancy ranks among the most prevalent forms of cancer and stands as the third principal cause of cancer-associated mortality. Recent studies indicate that inflammatory processes play a significant role in the initiation and advancement of various malignancies, colorectal cancer included. It explores inflammatory biomarkers, with C-reactive protein (CRP) being a key focus. While CRP's elevation during inflammation is linked to tumorigenesis, studies on its association with CRC risk are inconsistent, showing gender and methodological differences. Interleukin-6 (IL-6), TNF - α, and their receptors also play roles in CRC development, yet research findings vary. Adiponectin and leptin, secreted by adipocytes, have complex associations with CRC, with gender disparities noted. In terms of screening, non-invasive methods like fecal occult blood tests (FOBTs) are widely used, and combining biomarkers with iFOBT shows potential. Multi-omics techniques, including genomics and microbiomics, offer new avenues for CRC diagnosis. Overall, while evidence highlights the significance of inflammatory biomarkers in CRC risk prediction, larger prospective studies are urgently needed to clarify their roles due to existing inconsistencies and methodological limitations.

Colorectal cancer survival in Mexico: Leveraging a national health insurance database

PURPOSE

We estimated the 5-year overall, age at diagnosis- and stage-specific colorectal cancer survival in patients treated through their coverage with Seguro Popular.

METHODS

We conducted a retrospective study using a dataset that included 1418 colorectal cancer patients covered by Seguro Popular (Mexico's public health insurance system covering 60 % of the population) between 2013 and 2016. Deaths were identified using the Epidemiologic Death Statistics Subsystem registry, with a specialized algorithm for record linkage. The Kaplan-Meier method was used to estimate overall survival curves and the proportion of patients alive at various follow-up time points. We compared survival curves across subgroups using the log-rank test.

RESULTS

In this study the average age at diagnosis was 56 years with 31.9 % of patients diagnosed before the age of 50. Most cases (78.1 %) were diagnosed in advanced stages (i.e., III and IV), with nearly half of the cases originating in the rectum. The overall 5-year survival was 50 %, with higher survival (74 %) for patients with stage I-II and lower survival for those with stage III (58 %) and IV (33 %). While age at diagnosis was not associated with survival for early-stage colorectal cancer, younger patients with metastatic disease had a worse prognosis compared to older patients.

CONCLUSION

The 5-year overall colorectal cancer survival was 50 %, with variation by clinical stage. Almost 80 % of the population was diagnosed with advanced stages, underscoring the need for screening programs. Younger patients with metastatic disease exhibited a worse prognosis, highlighting the need for targeted interventions.

Evolving landscape of colorectal cancer: Global and regional burden, risk factor dynamics, and future scenarios (the Global Burden of Disease 1990-2050)

BACKGROUND

Presently, colorectal cancer (CRC) is the second leading cause of cancer-related deaths worldwide. We provided global, regional, and national estimates of the burden of CRC and their attributable risks from 1990 to 2021, aiming to guide screening, early detection, and treatment strategies, optimize healthcare resource allocation, and facilitate the rational management of burden of CRC.

METHODS

Using data derived from the Global Burden of Disease database, we estimated the incidence, mortality, and disability-adjusted life years (DALYs) of CRC. The temporal trends of the age-standardized rate of CRC were quantified by calculating the estimated annual percentage changes (EAPC). Deaths from CRC attributable to each risk factor that had evidence of causation with CRC were estimated. CRC's deaths and DALYs was forecast through 2050 by logistic regression with Socio-Demographic Index as a predictor, then multiplying by projected population estimates.

RESULTS

Globally, between 1990 and 2021, the incident cases, death cases, and DALYs attributed to CRC have doubled, the age-standardized incidence rate (ASIR) presented a slightly upward tendency, while the age-standardized death rate (ASMR) and the age-standardized DALYs rate (ASDR) exhibited a decreasing trend. From 1990-2021, the ASIR for males has an increased trend, while females presented a downward trend. The ASIR and ASDR of CRC were higher in high and high-middle sociodemographic index (SDI) countries. The ASIR of CRC in 165 countries and territories showed escalating trend. Globally, for males and both sexes combined, diet low in whole grains was the leading risk factor for age-standardized deaths from CRC in 2021. However, among females, diet low in milk was the leading risk factor. We forecast that 2.18 million (1.53-2.94) individuals will death for CRC worldwide by 2050, and the DALYs achieve 41.7 million (29.9-55.4) by 2050.

CONCLUSION

The doubling of incidence counts and mortality cases and the rising ASIR in most countries indicates a significant burden of CRC. Authorities should devise suitable measures to address the increasing burdens, such as optimizing screening programs, enhancing awareness and screening efforts for males, and reducing exposure to modifiable risk factors.

A Comparison of International Modeling Methods for Evaluating Health Economics of Colorectal Cancer Screening: A Systematic Review

OBJECTIVES

Cost-effectiveness analysis (CEA) is an accepted approach to evaluate cancer screening programs. CEA estimates partially depend on modeling methods and assumptions used. Understanding common practice when modeling cancer relies on complete, accessible descriptions of prior work. This review's objective is to comprehensively examine published CEA modeling methods used to evaluate colorectal cancer (CRC) screening from an aspiring modeler's perspective. It compares existing models, highlighting the importance of precise modeling method descriptions and essential factors when modeling CRC progression.

METHODS

MEDLINE, EMBASE, Web of Science, and Scopus electronic databases were used. The Consolidated Health Economic Evaluation Reporting Standards statement and data items from previous systematic reviews formed a template to extract relevant data. Specific focus included model type, natural history, appropriate data sources, and survival analysis.

RESULTS

Seventy-eight studies, with 52 unique models were found. Twelve previously published models were reported in 39 studies, with 39 newly developed models. CRC progression from the onset was commonly modeled, with only 6 models not including it as a model component.

CONCLUSIONS

Modeling methods needed to simulate CRC progression depend on the natural history structure and research requirements. For aspiring modelers, accompanying models with clear overviews and extensive modeling assumption descriptions are beneficial. Open-source modeling would also allow model replicability and result in appropriate decisions suggested for CRC screening programs.

Global, regional, and national trends in colorectal cancer burden from 1990 to 2021 and projections to 2040

Background

Colorectal cancer (CRC) is a common malignancy with notable recent shifts in its burden distribution. Current data on CRC burden can guide screening, early detection, and treatment strategies for efficient resource allocation.

Methods

This study utilized data from the latest Global Burden of Diseases, Injuries, and Risk Factors (GBD) Study. Initially, a series of descriptive statistics were performed on the incident cases, deaths, disability-adjusted life years (DALYs), and age-standardized rates (ASRs) of CRC. Percentage changes and average annual percentage changes (AAPC) were then calculated to understand the trends in CRC disease burden. Decomposition and frontier analyses were conducted, and finally, the Bayesian age-period-cohort (BAPC) model was used to predict changes in ASRs up to 2040.

Results

The GBD 2021 estimates indicate a significant increase in the global incident cases, deaths, and DALYs of CRC from 1990 to 2021. The age-standardized incidence rate (ASIR) increased (AAPC: 0.2), while the age-standardized mortality rate (ASMR) (AAPC: -0.72) and age-standardized DALYs rate (AAPC: -0.73) decreased. Males bore a higher disease burden than females, though the trends in disease burden changes were similar for both sexes. Although developed regions had higher incident cases, deaths, and DALYs, they showed more significant declines in ASRs. Decomposition analysis revealed that population growth and aging were the primary drivers of the increased disease burden. Frontier analysis showed that as the Socio-demographic Index increased, the disparity in CRC ASRs among countries widened, with developed regions having greater potential to reduce these rates. The By 2040, the BAPC model projects significant declines in global ASMR and age-standardized DALYs rates, while ASIR is expected to decrease in females but increase in males and across both sexes.

Conclusion

CRC remains a significant public health issue with regional and gender differences, necessitating region- and population-specific prevention strategies.

Risk of Colorectal Cancer Associated With Frequency of Colorectal Polyp Diagnosis in Relatives

BACKGROUND & AIMS

The aim of the study was to evaluate the association of frequency of polyp diagnosis in relatives with the risk of overall and early-onset colorectal cancer (CRC).

METHODS

Data from nationwide Swedish family cancer datasets (1964-2018) were leveraged to calculate standardized incidence ratios for individuals with a family history of polyp by frequency of polyp diagnosis in family members.

RESULTS

A total of 11,676,043 individuals were followed up for up to 54 years. Compared with the risk in individuals without a family history of colorectal tumor (n = 142,234), the risk of overall CRC was 1.4-fold in those with 1 first-degree relative (FDR) with 1-time polyp diagnosis (95% CI, 1.3-1.4; n = 11,035; early-onset standardized incidence ratio [SIR], 1.4; 95% CI, 1.3-1.5; n = 742). The risk was significantly higher in individuals with 1 FDR with 2 or more (frequent) polyp diagnoses (overall CRC: SIR, 1.8; 95% CI, 1.8-1.9; early-onset CRC: SIR, 2.3; 95% CI, 2.0-2.6). A rather similar risk was observed for individuals with ≥2 FDRs with 1-time polyp diagnosis (overall CRC: SIR, 1.9; 95% CI, 1.7-2.1; early-onset CRC: SIR, 2.2; 95% CI, 1.5-2.9). Individuals with ≥2 FDRs with frequent polyp diagnoses had a 2.4-fold overall risk (95% CI, 2.2-2.7) and a 3.9-fold early-onset risk (95% CI, 2.8-5.3). Younger age at polyp diagnosis in FDRs was associated with an increased risk of CRC. A family history of polyp in second-degree relatives was important only when there were frequent diagnoses of polyp.

CONCLUSIONS

A higher frequency of colorectal polyp diagnosis in relatives is associated with a greater risk of CRC, especially early-onset CRC. This risk is independent of number of affected relatives or youngest age at polyp diagnosis. These findings underscore the need for more personalized CRC screening strategies that are tailored to individuals with a family history of polyp.

Effectiveness of behavior change techniques to address barriers to follow-up colonoscopy: results from an online survey and randomized factorial experiment

BACKGROUND

Nonattendance at colonoscopy is associated with reduced colorectal cancer (CRC) survival.

PURPOSE

The aim of this research was to quantify barriers to colonoscopy and test the effectiveness of behavior change techniques (BCTs) to address them.

METHODS

Two studies were conducted. In the first study, participants were asked to imagine their next CRC screening result was abnormal, and were presented with the standard abnormal result letter used in the English CRC Screening Programme. Participants then completed a short survey. Multivariate regression tested associations between perceived barriers and intentions. In the second study, participants were randomly presented with a modified version of the abnormal results letter, which incorporated one or more BCTs, designed to target barriers identified in study 1, using a 28 factorial design. Participants then completed the same survey used in study 1. Multivariate regression tested the effectiveness of the BCTs to modify target barriers and intentions.

RESULTS

In study 1, 5 items were associated with intentions, namely "Lack of understanding that CRC can be asymptomatic," "Perceived importance of screening," "Transport/travel," "Shared decision making and family influenced participation," and "Fear of pain and discomfort" (all P's < .05). In study 2, the inclusion of a social support message, targeting "shared decision-making and family influenced participation," facilitated independent decision making and increased intentions (both P's < .05). There was no evidence to support the remaining 7 BCTs to modify barriers or intentions (all P's < .05).

CONCLUSIONS

Inclusion of a social support message facilitated independent decision-making and improved intentions.

Effectiveness of a novel artificial intelligence-assisted colonoscopy system for adenoma detection: a prospective, propensity score-matched, non-randomized controlled study in Korea

BACKGROUND/AIMS

The real-world effectiveness of computer-aided detection (CADe) systems during colonoscopies remains uncertain. We assessed the effectiveness of the novel CADe system, ENdoscopy as AI-powered Device (ENAD), in enhancing the adenoma detection rate (ADR) and other quality indicators in real-world clinical practice.

METHODS

We enrolled patients who underwent elective colonoscopies between May 2022 and October 2022 at a tertiary healthcare center. Standard colonoscopy (SC) was compared to ENAD-assisted colonoscopy. Eight experienced endoscopists performed the procedures in randomly assigned CADe- and non-CADe-assisted rooms. The primary outcome was a comparison of ADR between the ENAD and SC groups.

RESULTS

A total of 1,758 sex- and age-matched patients were included and evenly distributed into two groups. The ENAD group had a significantly higher ADR (45.1% vs. 38.8%, p=0.010), higher sessile serrated lesion detection rate (SSLDR) (5.7% vs. 2.5%, p=0.001), higher mean number of adenomas per colonoscopy (APC) (0.78±1.17 vs. 0.61±0.99; incidence risk ratio, 1.27; 95% confidence interval, 1.13-1.42), and longer withdrawal time (9.0±3.4 vs. 8.3±3.1, p<0.001) than the SC group. However, the mean withdrawal times were not significantly different between the two groups in cases where no polyps were detected (6.9±1.7 vs. 6.7±1.7, p=0.058).

CONCLUSIONS

ENAD-assisted colonoscopy significantly improved the ADR, APC, and SSLDR in real-world clinical practice, particularly for smaller and nonpolypoid adenomas.

Possibility of determining high quantitative fecal occult blood on stool surface using hyperspectral imaging

BACKGROUND

Fecal immunochemical tests are commonly performed for colorectal cancer screening. Instant fecal occult blood measurement in toilet bowel movements would improve convenience. Hyperspectral imaging (HSI) enables the nondestructive evaluation of materials that are difficult to assess visually. This study aimed to determine whether HSI could be used to identify fecal occult blood on stool surfaces.

METHODS

The study included 100 patients who underwent colonoscopy, divided into groups A and B (50 patients, each) for creating a discriminant algorithm and validating the accuracy of the algorithm, respectively. In group A, 100 areas were randomly selected from the stool surface, and the fecal occult blood quantitative values were measured and photographed using a hyperspectral camera (cutoff: > 400 ng/mL). A discriminant algorithm image was created to extract spectral feature differences obtained from HSI via machine learning. In group B, 250 random areas were evaluated and compared to fecal occult blood quantitative values, measuring sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV).

RESULTS

Groups A and B comprised 28 and 26 patients with cancer, respectively. Cancer detection sensitivity at the 400 ng/mL cutoff was 67.9% and 42.3% in groups A and B, respectively. The discriminant algorithm image exhibited high accuracy in group A (sensitivity; 77.1%, specificity; 96.9%, accuracy; 90.0%, PPV; 93.1%, NPV; 88.7%). In group B, the sensitivity, specificity, accuracy, PPV, and NPV were 83.3, 92.9, 90.8, 76.3, and 95.3%, respectively.

CONCLUSION

HSI can effectively discriminate high quantitative fecal occult blood, highlighting its potential for improved colorectal cancer screening.

Prognostic Value of Insulin Growth Factor-Like Receptor 1 (IGFLR1) in Stage II and III Colorectal Cancer and Its Association with Immune Cell Infiltration

IGFLR1 is a novel biomarker, and some evidences suggested that is involved in the immune microenvironment of CRC. Here, we explored the expression of IGFLR1 and its association with the prognosis as well as immune cell infiltration in CRC, with the aim to provide a basis for further studies on IGFLR1. Immunohistochemical staining for IGFLR1, TIM-3, FOXP3, CD4, CD8, and PD-1 was performed in eligible tissues to analyze the expression of IGFLR1 and its association with prognosis and immune cell infiltration. Then, we screened colon cancer samples from TCGA and grouped patients according to IGFLR1-related genes. We also evaluated the co-expression and immune-related pathways of IGFLR1 to identify the potential mechanism of it in CRC. When P < 0.05, the results were considered statistically significant. IGFLR1 and IGFLR1-related genes were associated with the prognosis and immune cell infiltration (P < 0.05). In stage II and III CRC tissue and normal tissue, we found (1) IGFLR1 was expressed in both the cell membrane and cytoplasm and which was differentially expressed between cancer tissue and normal tissue. IGFLR1 expression was associated with the expression of FOXP3, CD8, and gender but was not associated with microsatellite instability. (2) IGFLR1 was an independent prognostic factor and patients with high IGFLR1 had a better prognosis. (3) A model including IGFLR1, FOXP3, PD-1, and CD4 showed good prognostic stratification ability. (4) There was a significant interaction between IGFLR1 and GATA3, and IGFLR1 had a significant co-expression with related factors in the INFR pathway. IGFLR1 has emerged as a new molecule related to disease prognosis and immune cell infiltration in CRC patients and showed a good ability to predict the prognosis of patients.

Global, regional, and national burden of early-onset colorectal cancer and projection to 2050: An analysis based on the Global Burden of Disease Study 2021

OBJECTIVES

Early-onset colorectal cancer (EO-CRC) is becoming increasingly concerning due to its impact on individuals under 50 years old. We explored the burden of EO-CRC to provide information for planning effective management and prevention strategies.

STUDY DESIGN

We conducted secondary analyses to assess the burden of EO-CRC using data from GBD 2021.

METHODS

The incidence, prevalence, deaths, disability-adjusted life years (DALYs) and their rates across 204 countries and territories were obtained from GBD 2021 database. The estimated annual percentage change (EAPC) calculation was used to assess temporal trends in these metrics. Additionally, we reported the proportion of DALYs attributable to risk factors and projected future disease burden till 2050.

RESULTS

The global number of new EO-CRC cases increased from 107,310 in 1990 to 211,890 in 2021. Both age-standardized incidence rate (ASIR) and prevalence rate (ASPR) of EO-CRC showed overall increases over the study period (ASIR: EAPC = 0.96 (0.9-1.02), ASPR: EAPC = 1.5 (1.44-1.55)). However, a decline in ASIR and ASPR was observed in 2020 and 2021. Males consistently showed higher EO-CRC indicators compared to females. Furthermore, projections indicated that deaths and DALYs cases are likely to fluctuate but generally increase by 2050, reaching 85,602 and 4,283,093, respectively.

CONCLUSIONS

The global impact of EO-CRC has increased significantly from 1990 to 2021, revealing notable variations across SDI regions, countries, age groups, and sexes. Besides, deaths and DALYs are predicted to rise by 2050. These results highlight the importance of implementing measures to address the growing burden of EO-CRC globally.

When Should Colon Cancer Screening Begin? The Impact of Early-Onset Colorectal Cancer and the Reality of an Unscreened Older Population

BACKGROUND

Recent increases in colorectal cancer (CRC) incidence and mortality under age 50 have led the US to recommend starting screening at age 45 years instead of 50. Several other countries are now also reconsidering the age to start CRC screening.

AIMS

To aid decision makers in making an informed decision about lowering the starting age of CRC screening in their jurisdictions.

METHODS

In this article, we present the clinical and modeling evidence for the optimal age to start CRC screening and provide a checklist of considerations for decisions on age to start CRC screening.

RESULTS

Two observational studies showed that detection of advanced neoplasia in those aged 45-49 years undergoing colonoscopy was at least as high as in those aged 50-54 years. One Taiwanese study reported a 22% reduction in CRC incidence and a 39% reduction in CRC mortality from FIT screening in those 40-49 years compared to those 50 years and older. Nine modeling studies concluded that lowering the age to start screening to age 45 was cost-effective. However, lowering the start age can have negative spill-off effects, such as increased wait times for diagnostic colonoscopy for symptomatic individuals and decreased screening participation. In an effort to support decision making and prevent negative spill-off, the National Colorectal Cancer Screening Network in Canada proposed a Worksheet to determine the resource impact of earlier screening initiation.

CONCLUSIONS

Lowering the age to start CRC screening to 45 years likely leads to a reduction in CRC incidence and mortality but requires additional healthcare resources. Policy makers can use the worksheet to assess the expected increase and assess the feasibility within their jurisdictions.

Palmatine attenuates MYH9 mediated nuclear localization of AURKA to induce G2/M phase arrest in colorectal cancer cells

The mitotic kinase Aurora kinase A (AURKA), which plays a crucial role in cell cycle progression, represents a promising target for the treatment of colorectal cancer (CRC). Here, we found that AURKA is a target of a CRC suppressor, the Palmatine (PAL). However, the underlying mechanism remains elusive. This work aims to investigate the underlying mechanism how PAL suppresses CRC through AURKA. It was confirmed that AURKA played an important role in the development of CRC tumors through an Azoxymethane/Dextran sulfate sodium salt induced mice model and tissue microarrays of CRC-patients. Overexpression of AURKA was able to partially reverse the inhibitory effect of PAL on CRC cells, showing that PAL significantly inhibited the malignant phenotype and induced the G2/M phase arrest of CRC cells by down-regulating AURKA. Functional studies indicated that PAL attenuated the stability of AURKA protein and reduced its nuclear level, resulting in reduction of key proteins in the G2/M phase. Importantly, Co-IP and WB experiments suggested that Myosin heavy chain 9 (MYH9) interacted with AURKA and had an impact on its nuclear localization. PAL can decrease nuclear AURKA by reducing the interaction of AURKA and MYH9. Taken together, our study revealed that MYH9 as an auxiliary protein for the nuclear localization of AURKA and elucidated the mechanism that PAL reduced nuclear AURKA through inhibiting the interaction of AURKA and MYH9 to induce G2/M phase arrest in CRC cells. Therefore, this study may provide a theoretical basis of PAL for the treatment of CRC.

Adherence, risk perception, and attitudes towards colorectal cancer screening: A road to individualized screening?

BACKGROUND & AIMS

Colorectal cancer (CRC) ranks second globally in cancer-related deaths and there is ongoing debate on the best populational screening strategy. This study aimed to evaluate individuals' intention to adhere to CRC screening, screening method preference, and barriers to screening.

METHODS

Cross-sectional study conducted in northern Portugal, where a populational fecal occult blood test (FOBT) program is implemented. The validated PERCEPT-PREVENT tool was administered across 3 groups: a) not yet invited to screening b) accepted FOBT screening, and c) primary colonoscopy screening.

RESULTS

A total of 397 participants completed the PERCEPT-PREVENT questionnaire and were compared by screening status. Intention to adhere was reported at a high rate (95 %;n = 354) and was positively influenced by knowledge of the screening rationale (OR8.96, 95 %CI 3.61-22.25). Most were unaware of symptoms (64 %;n = 253), risk factors (68 %;n = 271), and associated screening procedure risks (58 %;n = 230). Lower barrier scores for FOBT (7 ± 3) compared to colonoscopy (10 ± 3) were observed for screening naïve respondents (p < 0.001). Previous FOBT screening led to a lower preference for colonoscopy (previous FOBT screening 56 % vs not yet invited to screening 75 % vs previous primary colonoscopy 90 %; p < 0.001).

DISCUSSION

A greater understanding of the screening rationale enhances adherence. FOBT was highly accepted among never-screened participants. Colonoscopy should be offered to FOBT decliners, as personalized screening approaches could improve participation rates.

Detecting Colorectal Neoplasia Using Specific Fecal Fluorogenic Protease-Sensitive Substrates: A Pilot Study

BACKGROUND

identification and removal of advanced adenomas (AA) reduce colorectal cancer (CRC) incidence and potentially mortality. CRC screening often uses fecal immunochemical testing to select high-risk individuals for colonoscopy, despite its low sensitivity for AA and relatively high false-positivity rate. Previous studies have linked proteases to CRC development through their ability to facilitate angiogenesis and immunoregulation. This study aims to identify colorectal neoplasia-associated proteases and their substrates as a potential noninvasive screening test, introducing an innovative application of fecal protease profiling, which has previously been limited to tissue samples.

METHODS

eighteen fluorogenic substrates were designed based on literature. Proteolytic degradation of these substrates was measured in fecal samples of patients with CRC (n = 12), AA (n = 9), nonadvanced adenomas (n = 10), and controls (n = 14). Substrate degradation was correlated to a matched human proteome data set, and underlying proteases were identified based on their recognition patterns. Experiments with protease inhibitors and ZnCl2 were performed to further characterize the involved proteases.

RESULTS

in total, 7 of the 18 substrates tested showed a significantly decreased proteolytic degradation in feces from patients with any colorectal neoplasia compared to the control group. The l-aspartic acid-l-glutamic acid substrate (ED) showed significantly decreased degradation in AA and CRC patients. ED degradation significantly decreased with the addition of ZnCl2 and the cysteine protease inhibitor NEM.

CONCLUSION

we successfully developed colorectal neoplasia-specific fluorogenic substrates, highlighting the ED substrate as a potential substrate for the detection of AA and CRC. Although the responsible proteases require further identification, our results suggest an association with calcium-dependent cysteine proteases.

A prospective comparison of two computer aided detection systems with different false positive rates in colonoscopy

This study evaluated the impact of differing false positive (FP) rates in two computer-aided detection (CADe) systems on the clinical effectiveness of artificial intelligence (AI)-assisted colonoscopy. The primary outcomes were adenoma detection rate (ADR) and adenomas per colonoscopy (APC). The ADR in the control, system A (3.2% FP rate), and system B (0.6% FP rate) groups were 44.3%, 43.4%, and 50.4%, respectively, with system B showing a significantly higher ADR than the control group. The APC for the control, A, and B groups were 0.75, 0.83, and 0.90, respectively, with system B also showing a higher APC than the control. The non-true lesion resection rates were 23.8%, 29.2%, and 21.3%, with system B having the lowest. The system with lower FP rates demonstrated improved ADR and APC without increasing the resection of non-neoplastic lesions. These findings suggest that higher FP rates negatively affect the clinical performance of AI-assisted colonoscopy.

The Effect of Hepatic Surgical Margins of Colorectal Liver Metastases on Prognosis: A Systematic Review and Meta-Analysis

Introduction: Colorectal cancer is the third most common malignancy, with around half of patients developing liver metastases. Hepatectomy is the preferred treatment, but its success depends on several factors, including surgical margins. Various surgical margins have been suggested to achieve optimal results. This systematic review and meta-analysis aim to explore the impact of negative surgical margins ranging from 1 to 10 mm, and >10 mm on survival, with the objective of identifying optimal surgical margins. Methods: A systematic literature search was conducted on the MEDLINE, Scopus, and Cochrane databases. The six included studies that examined the effect of surgical margins at the aforementioned distances on patient survival. Studies were assessed for risk of bias using the Quality in Prognosis Studies tool. Statistical analysis was performed using SPSS software. Results: The results of the meta-analysis revealed the superiority of wider surgical margins (>10) on overall survival compared to smaller margins (1-10 mm), as the HR was calculated to be 1.38 [1.10; 1.73]. Specifically, negative margins between 1 and 10 mm are linked to a 38% increased risk of mortality compared to margins larger than 10 mm. The low heterogeneity indicates consistent findings across studies, and the statistically significant hazard ratio underscores the importance of aiming for larger surgical margins to enhance patient outcomes. In the subgroup that included only studies in which patients received neoadjuvant therapy, the HR was 1.48 [1.06; 2.07], further emphasizing the importance of ensuring negative surgical margins in today's era. Conclusions: In summary, this systematic review and meta-analysis highlights the impact of surgical margin width on the survival of patients with colorectal liver metastases, as well as the importance of margin optimization in surgical management strategies.

Colon capsule endoscopy polyp detection rate vs colonoscopy polyp detection rate: Systematic review and meta-analysis

BACKGROUND

Colon capsule endoscopy (CCE) is a modern, non-invasive method for large bowel visualization, offering a less invasive alternative to traditional colonoscopy (TC). While TC remains the gold standard for comprehensive large bowel assessment, including the detection and treatment of various conditions, the effectiveness of CCE in detecting polyps is less established.

AIM

To systematically review and compare the polyp detection rates (PDR) of CCE and TC.

METHODS

A systematic literature search was conducted using four scientific databases: CINAHL, MEDLINE via EBSCO, Cochrane Library, and MEDLINE/PubMed. A standardized search command was utilized to ensure consistency. Full papers were retrieved if they compared PDR between CCE and TC and involved patients over 18 years old. A meta-analysis was then conducted using the meta package in R software.

RESULTS

Initially, 339 articles were identified, with 128 duplicates and 15 non-English articles excluded, leaving 196 for screening. After further exclusions, 9 articles were included in the review. The meta-analysis revealed minimal differences in PDR between CCE and TC. The pooled PDR for TC was 0.61 (95%CI: 0.48–0.72), and for CCE, it was 0.61 (95%CI: 0.48–0.73). The overall comparison of the pooled PDR of both methods was 0.96 (95%CI: 0.90–1.02), indicating that CCE is non-inferior to TC.

CONCLUSION

CCE has emerged as a modern and safe diagnostic alternative to TC for polyp detection, demonstrating non-inferiority when compared to the conventional method.

Plasma mutation profile of precursor lesions and colorectal cancer using the Oncomine Colon cfDNA Assay

BACKGROUND

Colorectal cancer (CRC) is the second leading cause of cancer death worldwide. Early detection of precursor lesions or early-stage cancer could hamper cancer development or improve survival rates. Liquid biopsy, which detects tumor biomarkers, such as mutations, in blood, is a promising avenue for cancer screening.

AIM

To assess the presence of genetic variants in plasma cell-free tumor DNA from patients with precursor lesions and colorectal cancer using the commercial Oncomine Colon cfDNA Assay.

MATERIAL AND METHODS

Cell-free DNA (cfDNA) samples from the plasma of 52 Brazilian patients were analyzed. Eight patients did not have any significant lesions (five normal colonoscopies and three hyperplastic polyps), 24 exhibited precursor lesions (13 nonadvanced adenomas, 10 advanced adenomas, and one sessile serrated lesion), and 20 patients with cancer (CRC). The mutation profile of 14 CRC-associated genes were determined by next-generation sequencing (NGS) using the Oncomine Colon cfDNA Assay in the Ion Torrent PGM/S5 sequencer.

RESULTS

Thirty-three variants were detected in eight genes (TP53, PIK3CA, FBXW7, APC, BRAF, GNAS, KRAS, and SMAD4). No variants were detected in the AKT1, CTNNB1, EGFR, ERBB2, MAP2K1 and NRAS genes. All variants were considered pathogenic and classified as missense or truncating. The TP53 gene harbored the most variants (48.48%), followed by the KRAS gene (15.15%) and the APC gene (9.09%). It was possible to detect the presence of at least one pathogenic variant in cfDNA in 60% of CRC patients (12/20) and 25% of precursor lesions (6/24), which included variants in three patients with nonadvanced adenoma (3/13 - 23.08%) and three with advanced adenomas (3/10 - 30%). No variants were detected in the eight patients with normal findings during colonoscopy. The detection of mutations showed a sensitivity of 60% and a specificity of 100% for detecting CRC and a sensitivity of 50% and a specificity of 100% for detecting advanced lesions.

CONCLUSION

The detection of plasma NGS-identified mutations could assist in early screening and diagnostic of CRC in a noninvasive manner.

Global Distribution of Colorectal Cancer Staging at Diagnosis: An Evidence Synthesis

BACKGROUND & AIMS

Stage at diagnosis is a key prognostic factor for colorectal cancer (CRC) survival. We aimed to assess the global distribution of CRC staging at diagnosis using population-based or hospital-based registry data.

METHODS

We systematically searched in MEDLINE and Embase from their inception until December 6, 2023. Gray literature was searched through published cancer reports. Studies from population-based or hospital-based cancer registries reporting the stage distribution of diagnosed CRC were included. We extracted stage-specific proportions among patients with CRC based on TNM; Surveillance, Epidemiology, and End Results; or Dukes staging systems. Subgroup analyses by sex, age, tumor site, calendar period, and status of population-based screening were performed. Correlations between the Human Development Index (HDI), Socio-Demographic Index (SDI), and the distant metastatic CRC proportion were also evaluated.

RESULTS

A total of 84 eligible studies/reports from 46 countries were analyzed, covering 3.8 million patients. Among 36 countries included in the main analysis, the most recent distant metastatic CRC proportions varied from 16.2% in Puerto Rico to 28.2% in Oman and Latvia, with a median of 23.7% (interquartile range, 21.8%-26.3%). Higher metastatic proportions were observed in younger patients, those with colon cancer, and those without screening implementation, with no apparent difference between males and females. Over time, some countries/regions, such as Southern Portugal (36.5% in 2000 to 22.2% in 2016), showed declining proportions of metastatic CRC, whereas others remained stable (eg, Austria, Belgium) or increased (eg, United States, Slovenia, Spain). Higher HDI and SDI were correlated with lower proportions of distant metastatic CRC (HDI: ρ = -0.48; SDI: ρ = -0.26).

CONCLUSION

Global disparities in CRC staging exist, indicating a need for targeted interventions to enhance early detection and management, especially in high-metastasis areas.

The baseline fecal microbiome differs in patients with and without anastomotic leakage after colorectal cancer surgery

Background

Anastomotic leakage (AL) is a severe complication of colorectal surgery. The risk of AL is affected by both surgery and patient factors. Gut microbiomes can be generated from the residual material from the fecal immunochemical test (FIT). We, therefore, examined if AL after colorectal cancer surgery could be associated with specific baseline microbiomes in the FIT screening sampling tubes collected weeks before surgery.

Methods

Samples from patients participating in the Danish colorectal cancer screening program were biobanked from 2016 to 2018, and samples from patients who had surgery for screening-detected cancer were included. They were matched with patients without AL in a 1:2 ratio based on age, sex, location of anastomosis (colonic/rectal), ASA classification, and smoking habits. Bacterial DNA was extracted from the sampling tubes, and the fecal microbiomes were analyzed with targeted 16S ribosomal RNA third-generation sequencing.

Results

18 patients who developed AL after surgery were matched with 36 without AL. The alpha diversity was lower in the AL group (p = 0.035), and the AL group separated from the Controls in the PCoA plot (p < 0.001). This was due to the patients undergoing rectal resections, with significant differences in alpha- and beta diversity (p = 0.025 and p = 0.002, respectively). The prevalence of bacteria with the potential to produce collagenase was higher in patients who developed AL (odds ratio 1.29 (95% CI 1.28-1.30), p < 0.001).

Conclusions

We found differences in the baseline microbiome profile associated with subsequent development of AL after surgery for screening-detected rectal cancer.

Development of an algorithm combining blood-based biomarkers, fecal immunochemical test, and age for population-based colorectal cancer screening

BACKGROUND AND AIMS

Implementation of screening modalities has reduced the burden of colorectal cancer (CRC), but high false positive rates pose a major problem for colonoscopy capacity. We aimed to create a tailored screening algorithm that expands the fecal immunochemical test (FIT) with a blood specimen and current age to improve selection of individuals for diagnostic colonoscopy.

METHODS

In this prospective multicenter study, 8 blood-based biomarkers (carcinoembryonic antigen, ferritin, high-sensitivity C-reactive protein, human epididymis protein 4, Cyfra21-1, hepsin, interleukin 8, and osteoprotegerin) were investigated in 1977 FIT-positive individuals from the Danish national CRC screening program undergoing follow-up colonoscopy. Specimens were analyzed on Architect i2000, Architect c8000 (both from Abbott, Chicago, Ill, USA), or Luminex xMAP machines (MilliporeSigma, St. Louis, Mo, USA). FIT analyses and blood-based biomarker data were combined with clinical data (ie, age and colonoscopy findings) in a cross-validated logistic regression model (algorithm) benchmarked against a model solely using the FIT result (FIT model) applying different cutoffs for FIT positivity.

RESULTS

The cohort included individuals with CRC (n = 240), adenomas (n = 938), or no neoplastic lesions (n = 799). The cross-validated algorithm combining the 8 biomarkers, quantitative FIT result, and age performed superior to the FIT model in discriminating CRC versus non-CRC individuals (area under the receiver operating characteristic curve, 0.77 vs 0.67, respectively; P < .001). When discriminating individuals with either CRC or high- or medium-risk adenomas versus low-risk adenomas or clean colorectum, the areas under the receiver operating characteristic curve were 0.68 versus 0.64 for the algorithm and FIT model, respectively.

CONCLUSIONS

The algorithm presented here can improve patient allocation to colonoscopy, reducing colonoscopy burden without compromising cancer and adenoma detection rates or vice versa.

TREM2-mediated Macrophage Glycolysis Promotes Skin Wound Angiogenesis via the Akt/mTOR/HIF-1α Signaling Axis

OBJECTIVE

The trigger receptor expressed on myeloid cells-2 (TREM2) pathway in myeloid cells is a key disease-inducing immune signaling hub that is essential for detecting tissue damage and limiting its pathological spread. However, the role and potential mechanisms of TREM2 in wound repair remain unclear. The purpose of this study was to determine the role and mechanism of TREM2 in skin wound healing in mice.

METHODS

Immunofluorescence staining was used to determine the expression and cellular localization of TREM2 and test the effects of TREM2 knockout on angiogenesis, glycolysis, and lactylation in skin tissue. Western blotting was used to analyze the expression of the Akt/mTOR/HIF-1α signaling pathway in the wounded skin tissues of wild-type (WT) and TREM2 knockout mice. A coimmunoprecipitation assay was used to determine whether HIF-1α, which mediates angiogenesis, is modified by lactylation.

RESULTS

The number of TREM2+ macrophages was increased, and TREM2+ macrophages mediated angiogenesis after skin injury. TREM2 promoted glycolysis and lactylation in macrophages during wound healing. Mechanistically, TREM2 promoted macrophage glycolysis and angiogenesis in wounded skin tissues by activating the Akt/mTOR/HIF-1α signaling pathway. HIF-1α colocalized with Klac to mediate lactylation in macrophages, and lactate could stabilize the expression of the HIF-1α protein through lactylation. Lactate treatment ameliorated the impaired angiogenesis and delayed wound healing in wounded skin in TREM2 knockout mice.

CONCLUSION

TREM2+ macrophage-mediated glycolysis can promote angiogenesis and wound healing. Our findings provide an effective strategy and target for promoting skin wound healing.

Burden of gastrointestinal cancers among adolescent and young adults in Asia-Pacific region: trends from 1990 to 2019 and future predictions to 2044

BACKGROUND

Gastrointestinal cancer is a significant cause of cancer incidence and mortality. Nevertheless, the epidemiology of the burden among adolescents and young adults (AYAs, aged 15-39 years) remains limited in the Asia-Pacific region, despite the region's significant population. This study aims to explore the gastrointestinal cancer burden among AYAs in the Asia-Pacific region for the year 2019, while also analysing trends from 1990 to 2019 and projecting future trends up to 2044.

METHODS

Annual case numbers, age-standardized rates of incidence, death, and disability-adjusted life-years (DALYs) and their estimated annual percentage changes (EAPCs) for gastrointestinal cancers were derived from the Global Burden of Disease, Injuries, and Risk Factors Study 2019. Trends over the next 25 years have also been predicted.

RESULTS

In 2019, there were 117,714 incident cases, 61,578 deaths and 3,483,053 DALYs due to gastrointestinal cancers in the Asia-Pacific region, accounting for 68.5%, 67.6% and 72.4%, respectively, of global gastrointestinal cancers in this population. The highest age-standardized rates occurred in countries with a middle Socio-demographic Index. From 1990 to 2019, there was a decline in the age-standardized rates of incidence, death and DALY attributed to gastrointestinal cancers, with EAPC of -1.10, -2.48 and -2.44, respectively. These rates are expected to stabilize over 25 years, with notable variations in individual gastrointestinal cancers.

CONCLUSIONS

Gastrointestinal cancers among AYAs in the Asia-Pacific region have posed a significant burden over the past 30 years and are expected to persist in the coming years.

Evaluation of a novel forward-looking optical coherence tomography probe for endoscopic applications: an ex vivo feasibility study

BACKGROUND

As a result of recent advances in the development of small microelectromechanical system mirrors, a novel forward-looking optical coherence tomography (OCT) probe with a uniquely large field of view is being commercially developed. The aim of this study is to prospectively assess the feasibility of this advanced OCT probe in interpreting ex vivo images of colorectal polyp tissue and to identify necessary steps for further development.

METHODS

A total of 13 colorectal lesions from 9 patients, removed during endoscopic resection, were imaged ex vivo with the OCT device and compared with histopathological images that served as the gold standard for diagnostics. Normal tissue from one patient, removed during the endoscopic procedure, was imaged as a negative control. We assessed the presence of features indicative for polyp type and degree of dysplasia, by comparing OCT images to histopathological images and by evaluating the presence of OCT-specific features identified by previous studies, such as effacement (loss of layered tissue structure), a hyperreflective epithelial layer, and irregularity of the surface.

RESULTS

As verified by corresponding histological images, tissue structures such as blood vessels and tissue layers could be distinguished in OCT images of the normal tissue sample. Detailed structures on histological images such as crypts and cell nuclei could not be identified in the OCT images. However, we did identify OCT features specific for colorectal lesions, such as effacement and a hyperreflective epithelial layer. In general, the imaging depth was about 1 mm.

CONCLUSION

Some relevant tissue structures could be observed in OCT images of the novel device. However, some adaptations, such as increasing imaging depth using a laser with a longer central wavelength, are required to improve its clinical value for the imaging of colorectal lesions.

Fecal Immunochemical Test Positivity Thresholds: An International Survey of Population-Based Screening Programs

BACKGROUND

The fecal immunochemical test for hemoglobin (FIT) is now a widely used non-invasive test in population-based organized screening programs for colorectal neoplasia. The positivity thresholds of tests currently in use are based on the fecal hemoglobin concentration (f-Hb), but the rationale for the adopted thresholds are not well documented. To understand current global usage of FIT in screening programs we conducted an international survey of the brands of FIT used, the f-Hb positivity threshold applied and the rationale for the choice.

METHODS

All members of the World Endoscopy Organization CRC Screening Committee were invited to complete an eight-element initial electronic survey exploring the key aims. Responses were obtained from 63 individuals, representing 38 specific locations in 28 countries. A follow-up survey on technical issues was offered to the 38 locations, with replies from 17 sites in 13 countries.

RESULTS

In-use quantitative FIT were provided by four main manufacturers; Minaris Medical (2 countries), Eiken Chemical Company/Polymedco (21), Alfresa Pharma (2) and Sentinel Diagnostics (4). Of the 38 screening sites, 15 used the threshold of 20 µg hemoglobin/g feces, while thresholds ranged between 8.5 and 120 ug/g in the remainder. Seven explanations were given for adopted FIT thresholds; maximizing the sensitivity for colorectal neoplasia (n = 23) was the most common followed by the availability of colonoscopy resources (n = 18). Predictive value, specificity, and cost effectiveness were less frequently reported as the rationale. Nine sites found it necessary to change the threshold that they had initially selected.

CONCLUSIONS

This international survey has documented the wide range of FIT positivity thresholds that are in current use. Quantitative FITs enable programs to achieve the desired program outcomes within available resource constraints by adjusting the positivity threshold. This supports the need for enabling positivity threshold adjustment of emerging new screening tests based on novel predictive biomarkers, rather than providing inflexible test endpoints.

Yield and Effectiveness of 2-Sample Fecal Immunochemical Test-Based Screening Program for Colorectal Cancer

BACKGROUND AND AIMS

Colorectal cancer (CRC) incidence and mortality of China account for nearly 30% of the global attributable fraction. We aimed to estimate the yield and effectiveness of a 2-sample fecal immunochemical test (FIT)-based screening program in China.

METHODS

Eligible individuals were invited for 2-sample FIT between 2007 and 2021, with positive ones (cutoff 40 μg/g before 2013 and 20 μg/g thereafter) referred for colonoscopy. Participation rates, detection rates, and positive predictive values were calculated. Participants were classified into: FIT+/colonoscopy compliers, FIT+/colonoscopy noncompliers, and FIT- as control subjects. We compared CRC incidence and mortality and calculated the age reaching comparable risk.

RESULTS

Among 246,349 invitees, 150,524 (61.10%) participated in 2-sample FIT, with 16,994 (11.29%) identified as FIT+; 12,816 (75.41%) underwent colonoscopy, yielding a detection rate and positive predictive value of 0.57% and 6.70% for advanced neoplasia, respectively. Median follow-up was 10.58 years. Compared with FIT- participants, CRC incidence and mortality were relatively similar among FIT+/colonoscopy compliers with hazard ratios of 0.94 (95% confidence interval [CI], 0.75-1.19) and 1.62 (95% CI, 1.09 to 2.41) but higher among noncompliers, with hazard ratios of 3.52 (95% CI, 2.85-4.34) and 4.41 (95% CI, 2.96-6.55). Taking CRC incidence and mortality risk of FIT- participants at 50.0 years of age as the benchmark, FIT+/colonoscopy compliers reached same risk at 50.6 and 46.1 years of age, while noncompliers reached the same risk at 38.0 and 37.9 years of age, respectively.

CONCLUSIONS

Two-sample FIT could effectively identify high-risk populations, and colonoscopy compliance is associated with a lower risk of CRC incidence and mortality. This strategy might facilitate CRC screening practice in countries with large populations.

Performance of DNA methylation and blood-borne tumor indicators in detecting colorectal neoplasia and adenomas: a comparative study with the fecal occult blood test

Objectives

To evaluate the performance of stool methylated syndecan2 (mSDC2), methylated septin9 (mSEPT9), fecal occult blood test (FOBT), carcinoembryonic antigen (CEA), carbohydrate antigen 125 (CA125) and carbohydrate antigen 199 (CA199) in detecting colorectal neoplasia and adenomas.

Methods

Blood-borne CEA, CA125, and CA199 levels were measured by electrochemiluminescence. The SDC2 methylation was detected by Methylation Detection Kit for Human SDC2 Gene (Real time PCR), and the SEPT9 methylation was detected by the Septin9 Gene Methylation Detection Kit based on PCR fluorescent probe assay. The colonoscopy combined with tissue biopsy pathology was used as a validation criterion for colorectal neoplasia.

Results

In detecting colorectal neoplasia, the AUCs of mSDC2, FOBT and mSEPT9 were 0.935 (95% CI: 0.915-0.956, P<0.001), 0.824 (95% CI: 0.617-1.000, P<0.001) and 0.671 (95% CI: 0.511-0.831, P<0.001), respectively. The sensitivity of mSDC2, FOBT and mSEPT9 were 100.0%, 66.7% and 40.0%, respectively. But the AUC of CEA, CA125 and CA199 were not statistically significant for colorectal neoplasia (all P>0.05). The combined application of mSEPT9 and mSDC2 showed the best predictive performance (AUC: 0.956, 95% CI: 0.887~1.000). For adenomas, the AUC of FOBT was extremely low (AUC: 0.524, 95% CI: 0.502-0.545, P=0.004). The CEA, CA125, CA199, mSEPT9 and mSDC2 were not statistically significant in detecting adenomas (all P>0.05).

Conclusions

For individual tests, FOBT and mSDC2 are relatively better indicators for detecting colorectal neoplasia compared to mSEPT9, CEA, CA125 and CA199. The combined form of mSEPT9 and mSDC2 to detect colorectal neoplasia has good predictive performance. However, none of these indicators demonstrated significant predictive power for detecting adenomas in our study.

An Adjustable Positivity Threshold for Non-invasive Screening Tests for Colorectal Neoplasms Can Improve Screening Program Effectiveness and Feasibility

BACKGROUND

In two-step population screening for colorectal cancer (CRC), a simple non-invasive test, commonly a fecal immunochemical test for hemoglobin (FIT), is first undertaken to predict, based on the fecal hemoglobin concentration (f-Hb), who is more likely to have colorectal neoplasia and needs colonoscopy.

AIM

To evaluate the importance of being able to adjust the f-Hb threshold that triggers follow-up colonoscopy (the "positivity threshold"), we evaluated the predictive value of f-Hb for colorectal neoplasia and its implications for the configuration of new non-invasive tests.

METHODS

A literature review was conducted on the use of quantitative FIT to select the positivity threshold, followed by using f-Hb from a large population to model how adjusting the positivity threshold enabled achievement of the desired program outcomes in a feasible manner.

RESULTS

The literature review and the modeling found that while the f-Hb positivity threshold is predictive for colorectal neoplasia across a wide range of f-Hb, there is a complex relationship between program outcomes and f-Hb. The threshold determines not just clinical accuracy (including true- and false-positive results for CRC and/or advanced precursor lesions), but also the colonoscopy workload. A lower f-Hb threshold is associated with a higher sensitivity for neoplasia but a lower specificity and a heavier load of follow-up colonoscopies. Consequently, the threshold determines a program's impact on population CRC mortality and incidence, but also its feasibility and cost-effectiveness within a health-care system.

DISCUSSION

We are entering a new era of non-invasive screening tests, where multiple biomarkers found in biological samples such as blood as well as feces, are being developed and evaluated. These typically specify a non-transparent algorithm, developed with machine learning, to provide a predictive dichotomous positive/negative result with a fixed associated clinical accuracy and colonoscopy workload. This will restrict use of new tests in jurisdictions where the accuracy and workload implications do not match the desired screening program outcomes.

CONCLUSION

However, similar to flexible FIT positivity thresholds, it would be ideal if new tests also provide capacity for screening program providers to select the positivity threshold that delivers their desired screening outcomes in a feasible manner. How marketing, distribution and reimbursement of non-invasive tests are approved, funded and implemented varies widely across jurisdictions and must be taken into account.

Non-gastrointestinal symptom burden following colorectal cancer treatment-a systematic review

BACKGROUND

Colorectal cancer is one of the most common malignancies worldwide. Improvements in screening and treatment have allowed for earlier detection and longer survival. However, treatments, which may involve surgery, radiotherapy and/or chemotherapy, often lead to patients developing both gastrointestinal and non-gastrointestinal symptoms that can persist long term. This systematic review aims to understand better the non-gastrointestinal symptoms that patients develop after colorectal cancer treatment and how these are identified and assessed through the use of questionnaires.

METHOD

The review was conducted according to PRISMA guidelines. Scopus, PubMed, Web of Science, PsycINFO and Cochrane Library were searched. Eligible studies evaluated the non-gastrointestinal symptoms that patients had developed and continued to have at 12 months or longer after treatment. Studies that were performed on patients who were within 12 months of treatment, who had a recurrent or a secondary cancer, had stage 4 cancer/were palliative or that looked solely at gastro-intestinal symptoms were excluded. Articles were limited to studies on human subjects written in English published between February 2012 and July 2024.

RESULTS

The searches identified 3491 articles. Thirty-seven articles met the inclusion criteria, of which, 33 were quantitative, 2 were qualitative and 2 were mixed methods study designs. Nearly two-thirds (n = 22) were cross-sectional studies, whereas 14 were longitudinal. One study had both a cross-sectional and longitudinal component to it. Most studies were of medium to high quality based on the Newcastle Ottawa Scale (n = 23) and were conducted in 14 countries, the majority of which were performed in the Netherlands (n = 14). The majority of participants in the included studies (n = 30/37) were men. There were also three studies that were performed with only female participants and one study that was performed with male participants only. The age range of research participants across all the studies was 29 to 89 years. Forty-five different validated questionnaires containing 5-125 question items were used to collect information on the side effects and impact of colorectal cancer treatment. Completion rate for questionnaires varied from 30 to 100% (median 63.5%). These determined effects on quality of life, emotional/psychological distress, sexual and urinary dysfunction, neuropathy, fatigue and hip pain.

CONCLUSION

This systematic review highlighted a wide range of longer-term non-gastrointestinal symptoms that frequently adversely affect QoL following treatment. These studies included highlighting the importance of nutrition/diet, physical activity, spirituality and communication in managing these long-term side effects.

Challenges around diagnosis of early onset colorectal cancer, and the case for screening

BACKGROUND

Colorectal cancer (CRC) is the third most diagnosed cancer in the world, with an estimated 1.93 million cases diagnosed in 2020. While the overall CRC incidence in many countries is falling there has been a dramatic increase in CRC in those aged under 50 (early onset colorectal cancer, EOCRC). The reason for this increase in EOCRC is unknown. As the best predictor of survival is stage at diagnosis, early diagnosis is likely to be beneficial and population screening may facilitate this.

METHODS

A narrative review of the literature was undertaken.

RESULTS

Improving time to diagnosis in symptomatic patients is beneficial. However, by the time symptoms develop, over a third of patients already have metastatic disease. Screening asymptomatic patients (with Faecal Immunochemical test (FIT) and colonoscopy) has been proved to be effective in older patients (>60 years). In younger populations, the decreasing incidence rates of CRC previously made cost effectiveness, compliance and therefore benefit questionable. Now, with the increasing incidence of CRC in those under 50 years of age, modelling suggests screening with FIT and colonoscopy is cost effective from 40 years of age. There is evidence that some countries screening below 50 have prevented the rise in EOCRC incidence. Additionally the use of new and novel non-invasive biomarkers may also be able to improve the accuracy of screening asymptomatic patients.

CONCLUSION

Diagnosis of EOCRC once symptoms develop is often too late, and screening patients from age 40 is the best way to improve outcomes in this group.

Enhancing Colorectal Cancer Screening with Droplet Digital PCR Analysis of Fusobacterium nucleatum in Fecal Immunochemical Test Samples

Fecal immunochemical test (FIT) followed by colonoscopy in positive cases is commonly used for population-based colorectal cancer screening. However, specificity of FIT for colorectal cancer is not ideal and has poor performance for advanced adenoma detection. Fecal Fusobacterium nucleatum (Fn) detection has been proposed as a potential noninvasive biomarker for colorectal cancer and advanced adenoma detection. We aimed to evaluate the diagnostic performance of Fn detection using droplet digital PCR (ddPCR) in FIT samples from individuals enrolled in a colorectal cancer screening program with colorectal adenoma or cancer. We evaluated Fn presence in DNA isolated from FIT leftover material of 300 participants in a colorectal cancer screening program using ddPCR. The Fn DNA amount was classified as Fn-low/negative and Fn-high, and the association with patients' clinicopathological features and accuracy measurements was calculated. Fn-high levels were more prevalent in FIT-positive (47.2%, n = 34 of 72) than FIT-negative samples (28.9%, n = 66 of 228; P < 0.04). Among FIT-positive samples, high Fn levels were significantly more frequent in patients with cancer (CA, n = 8) when compared to normal (NT, n = 16; P = 0.02), non-advanced adenomas (NAA, n = 36; P = 0.01), and advanced adenomas (AA, n = 12; P = 0.01). Performance analysis of Fn in FIT-positive samples for colorectal cancer detection yielded an AUC of 0.8203 [confidence interval (CI), 0.6464-0.9942], with high sensitivity (100%) and specificity of 50%. Concluding, we showed the feasibility of detecting Fn in FIT leftovers using the ultrasensitive ddPCR technique. Furthermore, we highlighted the potential use of Fn levels in fecal samples to ameliorate colorectal cancer detection. Prevention Relevance: Fusobacterium nucleatum detection by droplet digital PCR could prioritize the selection of fecal immunochemical test-positive individuals who might benefit the most from the colonoscopy procedure.

Personalised medicine based on host genetics and microbiota applied to colorectal cancer

Colorectal cancer (CRC) ranks second in incidence and third in cancer mortality worldwide. This situation, together with the understanding of the heterogeneity of the disease, has highlighted the need to develop a more individualised approach to its prevention, diagnosis and treatment through personalised medicine. This approach aims to stratify patients according to risk, predict disease progression and determine the most appropriate treatment. It is essential to identify patients who may respond adequately to treatment and those who may be resistant to treatment to avoid unnecessary therapies and minimise adverse side effects. Current research is focused on identifying biomarkers such as specific mutated genes, the type of mutations and molecular profiles critical for the individualisation of CRC diagnosis, prognosis and treatment guidance. In addition, the study of the intestinal microbiota as biomarkers is being incorporated due to the growing scientific evidence supporting its influence on this disease. This article comprehensively addresses the use of current and emerging diagnostic, prognostic and predictive biomarkers in precision medicine against CRC. The effects of host genetics and gut microbiota composition on new approaches to treating this disease are discussed. How the gut microbiota could mitigate the side effects of treatment is reviewed. In addition, strategies to modulate the gut microbiota, such as dietary interventions, antibiotics, and transplantation of faecal microbiota and phages, are discussed to improve CRC prevention and treatment. These findings provide a solid foundation for future research and improving the care of CRC patients.

Who should be screened for colorectal cancer and how can it be prevented more effectively?

In this editorial, we comment on the article published by Agatsuma et al in a recent issue of the World J Gastroenterol (2024; 30: 1368-1376). We firmly concur with Agatsuma et al regarding the vital significance of colorectal cancer (CRC) screening as a public health strategy to diminish disease burden. Individuals exposed to risk factors for CRC, those with comorbid conditions, and those with limited health literacy should undergo screening. However, we believe that more regular screenings should be accompanied by a greater focus on primary prevention (PP) of CRC. CRC remains a significant global health challenge, and its incidence is strongly linked to age, lifestyle, and socioeconomic factors. It is particularly noteworthy that the majority of CRC patients are diagnosed outside of established screening pathways and frequently at an advanced stage of the disease, and the majority of patients possess inadequate or even nonexistent knowledge regarding CRC, which significantly impacts the prognosis and imposes a substantial economic burden. This study revealed that CRC identified during hospital visits for comorbid conditions was typically diagnosed at an earlier stage than detected via symptomatic pathways. Remarkably, early incidental detection of CRC aligns closely with the timing of discovery through routine cancer screenings. This suggests that by adopting more inclusive screening protocols that combine opportunistic testing with traditional screening methods, health care systems can create a more comprehensive safety net for individuals at risk of CRC. However, before maximizing the health benefits of screening programs, it is essential to make additional efforts prior to screening, such as raising awareness via public education, risk assessment, and personalized recommendations, enhancing the knowledge and skills of health care professionals, optimizing the accessibility and convenience of screening processes, ensuring the quality and safety of screening services, strengthening follow-up and support systems, and providing policy support and financial investment. The establishment of a comprehensive screening system often requires substantial investment in human, material, and financial resources, which can be challenging to achieve in regions with limited health care resources. Strengthening PP strategies can reduce the disease burden by targeting the cause, representing a more cost-effective and impactful approach. Establishing a comprehensive cancer PP service platform that integrates authoritative public education on malignant tumor PP, individualized malignant tumor risk assessment, and self-health management assistance accessible to the entire population will significantly enhance the overall effectiveness of CRC PP strategies.

Discovery and validation of colorectal cancer tissue-specific methylation markers: a dual-center retrospective cohort study

BACKGROUND AND PURPOSE

Early detection, diagnosis, and treatment of colorectal cancer and its precancerous lesions can significantly improve patients' survival rates. The purpose of this research is to identify methylation markers specific to colorectal cancer tissues and validate their diagnostic capability in colorectal cancer and precancerous changes by measuring the level of DNA methylation in stool samples.

METHOD

We analyzed samples from six cancer tissues and adjacent normal tissues and fecal samples from 758 participants, including 62 patients with interfering diseases. Bioinformatics databases were used to screen for candidate biomarkers for CRC, and quantitative methylation-specific PCR methods were applied for identification. The methylation levels of the candidate biomarkers in fecal and tissue samples were measured. Logistic regression and random forest models were built and validated using fecal sample data from one of the centers, and the independent or combined diagnostic value of the candidate biomarkers in fecal samples for CRC and precancerous lesions was analyzed. Finally, the diagnostic capability and stability of the model were validated at another medical center.

RESULTS

This study identified two colorectal cancer CpG sites with tissue specificity. These two biomarkers have certain diagnostic power when used individually, but their diagnostic value for colorectal cancer and colorectal adenoma is more significant when they are used in combination.

CONCLUSION

The results indicate that a DNA methylation biomarker combined diagnostic model based on two CpG sites, cg13096260 and cg12587766, has the potential for screening and diagnosing precancerous lesions and colorectal cancer. Additionally, compared to traditional diagnostic models, machine learning algorithms perform better but may yield more false-positive results, necessitating further investigation.

Co-designing planning interventions to facilitate participation in mail-out bowel cancer screening

BACKGROUND

Population mail-out bowel cancer screening programs save lives through prevention and early detection; however, their effectiveness is constrained by low participation rates. Many non-participants are "intenders"; that is, they intend to screen but fail to do so, often forgetting or procrastinating. This study aimed to co-design interventions to increase screening participation among intenders in the Australian National Bowel Cancer Screening Program.

METHODS

Three semi-structured interviews, and one online cross-sectional survey, were conducted between August 2021 and December 2022. Interviews with people who had completed and returned their latest screening kit ("completers") were first conducted to identify the planning strategies they had used. Using survey data, logistic regressions were conducted to analyse strategies predictive of participants having returned their latest bowel cancer screening kit. Then, intenders were interviewed to explore their opinions of these strategies and worked with researchers to adapt these strategies into prototype interventions to facilitate screening participation. All interviews were analysed using the framework approach of codebook thematic analysis.

RESULTS

Interview participants who returned their kit shared their effective planning strategies, such as putting the kit in a visible place or by the toilet, planning a time at home to complete the kit, and using reminders. Survey participants who reported using such strategies were more likely to have completed their screening kit compared to those who did not. Prototype interventions developed and endorsed by intenders included providing a prompt to place the kit or a sticker near the toilet as a reminder, a deadline for kit return, the option to sign up for reminders, and a bag to store the sample in the fridge.

CONCLUSIONS

These novel, consumer-led interventions that are built upon the needs and experience of screening invitees provide potential solutions to improve participation in population bowel cancer screening.

CEUS compared with CECT, MRI, and FDG-PET/CT for diagnosing CRC liver metastases: a diagnostic test accuracy systematic review and meta-analysis

OBJECTIVE

To determine the diagnostic accuracy of contrast-enhanced ultrasound (CEUS) compared with contrast-enhanced computed tomography (CECT), magnetic resonance imaging (MRI), and Fluorine-18-deoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) for diagnosing suspected liver metastases in patients with newly diagnosed colorectal cancer (CRC).

METHODS

The meta-analysis using the bivariate model included studies on patients with newly diagnosed CRC only and excluded patients with non-CRC liver metastases, known liver metastases, patients treated with chemotherapy and local treatments, e.g. hepatic resection or radiofrequency ablation. We used QUADAS-2 to assess the methodological quality of the studies.

RESULTS

We included 32 studies, 6 studies evaluated the accuracy of CEUS (n = 937 participants), 26 studies evaluated CECT (n = 2,582), 8 studies evaluated MRI (n = 564) and 6 studies evaluated FDG-PET/CT (n = 813). Sensitivity: FDG-PET/CT 94.4% [95% CI: 90.7-98.1%], MRI 92.9% [95% CI: 88.8-97.0%], CEUS 86.1% [95% CI: 78.0-94.3%] and CECT 84.6% [95% CI: 79.3-89.9%]. Specificity FDG-PET/CT 97.9% [95% CI: 95.9-99.9%], CEUS 96.1% [95% CI: 93.6-98.6%], MRI 94.4% [95% CI: 90.5-98.3%], and CECT 94.3% [95% CI: 91.8-96.8%].

CONCLUSION

FDG-PET/CT had significantly higher sensitivity and specificity than CECT, and significantly higher sensitivity than CEUS. MRI had a significantly higher sensitivity than CEUS, but a lower non-significant specificity. CECT had the lowest sensitivity and specificity.

PROSPERO REGISTRATION DETAILS

CRD42017055015 and CRD42017082996.

Gastric Cancer Screening: Intention to Adhere and Patients' Perspective

BACKGROUND AND AIMS

Gastric cancer (GC) is the third cause of cancer mortality worldwide. A screening strategy that combines an upper gastrointestinal endoscopy (UGIE) with a screening colonoscopy may be cost-effective in intermediate-risk regions. This study aimed to evaluate the intention to adhere to combined endoscopic screening and assess knowledge of GC symptoms, risk factors, and barriers to screening.

METHODS

Cross-sectional study enrolling individuals eligible for CRC screening in northern Portugal, where a populational fecal occult blood test (FOBT) program is implemented. The validated PERCEPT-PREVENT tool was applied across three groups: (a) not yet invited to CRC screening, (b) FOBT-positive referred to colonoscopy, and (c) primary colonoscopy screening.

RESULTS

A high acceptance rate was observed for combined endoscopic screening (94%; n = 264) [not yet invited to CRC screening 98% (n = 90) vs. FOBT-positive referred to colonoscopy 90% (n = 103) vs. primary colonoscopy 97% (n = 71); p = 0.017], with the vast majority reporting intention to adhere in the setting of full reimbursement (97%; n = 255). Most respondents were unaware of any possible GC symptom (76%; n = 213), risk factor (73%; n = 205), and UGIE-related complication (85%; n = 237). Regular follow-up with the primary care physician (Odds Ratio (OR) 27.59, 95% confidence interval (CI) 2.99-254.57), lower perceived negative health consequences of UGIE (OR 1.40, 95% CI 1.13-1.74), and lower perceived financial burden (OR 2.46, 95% CI 1.04-5.85) were the only factors independently associated with a higher intention to undergo combined screening.

CONCLUSIONS

Willingness to undergo combined endoscopic screening was notably high and positively impacted by lower perceived barriers. Additional efforts should be undertaken to improve levels of digestive health literacy.

Combining FITs and HRFQ with colonoscopy improve the cost-effectiveness of a 9-year mass colorectal cancer screening program

BACKGROUND

Colorectal cancer (CRC) incidence has been increasing. Colonoscopy is still a gold standard method for its early diagnosis but using colonoscopy alone as a mass screening method is unrealistic. This study is to investigate whether combining fecal immunochemical test (FIT) and high-risk-factors questionnaire (HRFQ) with colonoscopy improve the cost-effectiveness of a mass CRC screening.

PATIENTS AND METHODS

CRC screening protocol combining FITs and HRFQ in the first stage and colonoscopy in the second stage was used in 50 villages/towns in 2007-2015. Residents aged 40-74 years were eligible for this free screening. A total of 160 210 (76.12%) participants completed first-stage screening, and 28 679 (17.90%) participants were defined as positive, among which 21 715 (75.72%) participants completed colonoscopy and were included in the final analysis. Outcomes were followed up until 2020.

RESULTS

The compliance was 76.12% and 75.72% in the first and second screening stage, respectively. A total of 252 CRC, 4033 adenoma, 1234 advanced neoplasm, and 5534 total neoplasm cases were detected in the screening. The positive predictive values of CRC, adenoma, advanced neoplasm, and total neoplasm were higher in FITs+ than those in the HRFQ+ population, respectively. A total of 64.60% and 43.42% total neoplasm cases were found in FITs+ and HRFQ+ (8.02% for both), respectively. The total colorectal neoplasm and CRC cases detected by combining HRFQ and FITs increased by 55.08% and 40.00%, respectively, and their increases were higher compared to HRFQ. The detection cost per any neoplasm by combining HRFQ and FITs was <$5331, while that by FITs and HRFQ alone was <$4570 and $5380, respectively.

CONCLUSIONS

Combining FITs and HRFQ with colonoscopy improve the cost-effectiveness of a mass CRC screening program. This protocol can be recommended for most populations, especially those in the countries and areas with high population density and low physician/population ratio.

Insights Into Colorectal Cancer Screening: A Multidatabase Cohort Study of Over 1.5 Million Taiwanese

INTRODUCTION

Colorectal cancer (CRC) remains a significant public health concern. This study aims to provide a comprehensive understanding of the effectiveness of fecal immunochemical test (FIT) screening on CRC incidence and mortality, leveraging the scale of over 1.5 million randomly selected Taiwanese and more than 11.7 million person-years of follow-up.

METHODS

This prospective cohort study merges data from 3 robust Taiwanese health databases: the CRC screening program, cancer registration, and death registration databases. Incidence and mortality rates of CRC were calculated based on age, sex, urbanization, and past screening status. Cox proportional hazard models were used to assess the association between screening statuses and CRC incidence or mortality, adjusting for age, sex, and urbanization levels. Statistical analysis of the data was conducted in 2021-2022.

RESULTS

FIT screening was associated with a 33% reduction in CRC incidence and a 47% reduction in mortality. The study identified a dose-response relationship between the fecal hemoglobin concentration (f-HbC) levels and CRC risk. Participants with consistent FIT-negative results had significantly reduced CRC incidence and mortality risks, while those with one or more positive FIT results faced increased risks. Notably, compliance with follow-up examinations after a positive FIT significantly lowered mortality risk.

CONCLUSIONS

This large-scale study validates the efficacy of FIT screening in reducing CRC incidence and mortality. It offers a nuanced understanding of how various screening statuses impact CRC risks, thus providing valuable insights for public health strategies aimed at CRC prevention.

Barriers and facilitators to colonoscopy for cancer detection: patient and practitioner perspectives

OBJECTIVE

To further understand the barriers and facilitators to attending colonoscopy examination following a positive routinely offered stool test result, from the perspective of patients and Specialist Screening Practitioners (SSPs).

METHODS

Qualitative semi-structured interviews were conducted. Participants (N = 32) were patients (n = 20) who, as part of the Bowel Cancer Screening Programme (BCSP) in England, were invited to attend a colonoscopy examination, and SSPs (n = 12), who worked for the BCSP in England. Framework analysis included inductive and deductive coding.

RESULTS

Anxiety was as a key barrier cited by patients and SSPs, arising from the moment the patient received the invitation letter. Notably, procedural-related anxieties centred upon the fear of pain and discomfort and test invasiveness. The role of family, friends and the SSP were recognised by patients and SSPs to facilitate participation. Many patients, yet not SSPs, emphasised an obligation to attend all medical test invitations.

CONCLUSION

Practically orientated strategies suggested by patients and SSPs address the patient barriers identified. These include earlier information to patients on the option of sedation for pain relief, earlier notification of potential financial support for patients unable to fund their own travel costs, and fewer uses of the term cancer within written materials.

The aminophospholipid transporter, ATP8B3, as a potential biomarker and target for enhancing the therapeutic effect of PD-L1 blockade in colon adenocarcinoma

BACKGROUND

Colon adenocarcinoma (COAD) is a prevalent malignant tumor globally, contributing significantly to cancer-related mortality. COAD guidelines label MSI (Microsatellite instability) and MSS (Microsatellite stability) subtypes as global classification criteria and treatment strategy selection criteria for COAD. Various combination therapies involving PD-L1 inhibitors and adjuvant therapy to enhance anti-tumor efficacy.

METHODS

Datasets from single-cell RNA sequencing and bulk RNA sequencing in the TCGA and GEO databases were utilized to identify differentially expressed genes (DEGs). Furthermore, the correlation between ATP8B3 and PD-L1 was validated using siRNA, shRNA, and western blot analysis. Additionally, the association between ATP8B3 and immune checkpoint blockade (ICB) therapy was investigated through immune infiltration analysis and flow cytometry in both in vivo and in vitro assays.

RESULTS

In the COAD patient group, ATP8B3 significantly contributed to the establishment of an immunosuppressive microenvironment. Inhibiting ATP8B3 led to a reduction in PD-L1 expression in colon cancer cell lines. Additionally, ATP8B3 expression levels could serve as a potential guide for PD-L1 treatment in MSI-H COAD patients, with higher ATP8B3 expression associated with increased sensitivity to PD-L1 therapy. However, due to the lack of immuno-killer cells in the microenvironment of MSS subtypes, elevated ATP8B3 expression couldn't increase the sensitivity of MSS COAD patients to PD-L1 inhibitors.

CONCLUSION

Our research results support that Inhibiting ATP8B3 could enhance TIL (tumor-infiltrating lymphocyte) infiltration by reducing PD-L1 expression in MSI-H COAD, thereby serving as an effective strategy to improve PD-L1 blocker efficacy. The treatment strategy of combining ATP8B3 inhibitors and immunotherapy for MSI/MSS COAD patients will be the best choice.

Experience and satisfaction of participants in colorectal cancer screening programs: a qualitative evidence synthesis

BACKGROUND

Experience and satisfaction of colorectal cancer screening program participants are among the key factors that determine adherence to these programs. Understanding them is crucial to ensure future participation.

OBJECTIVES

To explore and gain understanding on the experience and satisfaction of the average-risk population participating in colorectal cancer screening programs.

METHODS

A Qualitative Evidence Synthesis. We conducted a literature search up to April 2023 in Medline, Embase, CINAHL, PsycINFO and ProQuest Dissertations and Thesis. We independently selected the studies for their inclusion, assessed their methodological quality (with CASP tool) and extracted data. Disagreements were solved by consensus. We thoroughly read the selected studies, and analyzed the data following a thematic synthesis approach. We evaluated the confidence in our findings with CERQUAL.

RESULTS

We included six studies: four had an appropriate quality, and two had some methodological limitations. We identified five main findings across studies: (1) Variability in the concerns about the results; (2) Challenges regarding procedure logistics; (3) Care received from the healthcare professionals; (4) Being adequately informed; (5) Expectations and experience with the program. All findings had a moderate level of confidence.

CONCLUSIONS

Our qualitative review provides a picture of the experience and satisfaction of the average-risk population participating in colorectal cancer screening programs. Despite some logistical and expectation management issues, the overall satisfaction with the programs is high. More research is needed on the topic, as there are still important gaps in knowledge.