Effectiveness of Screening Modalities in Colorectal Cancer: A Network Meta-Analysis

Diagnostic and screening potential of plasma exosome miR‑99b‑5p and its combination with other miRNAs for colorectal cancer

Extracellular vesicles (EVs) secreted by tumor cells have been documented to hold viable biomarker potential. Therefore, the present study evaluated the potential clinical value of EV-microRNAs (miRNAs or miRs) in the plasma exosomes of patients with colorectal cancer (CRC) for the early diagnosis and screening of CRC. In total, 95 plasma samples were collected at The Third Affiliated Hospital of Guangzhou Medical University (Guangzhou, China) between 2017 and 2019. Specifically, 68 samples were from patients with CRC and 27 were from healthy control (HC) donors. High-throughput sequencing was used to detect the expression of miRNAs in the isolated plasma EVs, which was subsequently verified by reverse transcription-quantitative PCR. Receiver operating characteristic (ROC) curves were used to analyze the diagnostic potential of single and combined miRNAs for CRC. Bioinformatics analysis was employed to predict the target genes of candidate miRNAs. Compared with those in the HC group, the CRC group expressed higher levels of miR-99b-5p and miR-409-3p, especially during the early stages of CRC. Clinicopathological analysis confirmed the higher expression levels of miR-99b-5p during the early stages, as well as higher expression levels in the colon compared with those in the rectum. ROC curve analysis revealed that the area under the curve (AUC) of miR-99b-5p for the diagnosis of early CRC was 73.5% (P=0.007). The early diagnostic capability of miR-99b-5p combined with miR-409-3p for CRC was evaluated, and the AUC was found to be 74.1% (P=0.006). In addition, the AUC of the combination of miR-99b-5p, miR-409-3p and carcinoembryonic antigen was 81.2% (P<0.001), indicating that this three-parameter combination displayed higher diagnostic power compared with any single miRNA for early CRC screening. The results from the present study suggest that the expression of miR-99b-5p in plasma exosomes is significantly upregulated in CRC, which holds potential for the early diagnosis of this cancer type. Such potential can be enhanced further by combining it with other miRNAs. Therefore, the present study provides a comprehensive but preliminary insight for the viability of miR-99b-5p (alone or combined with other miRNAs) for CRC diagnosis, which requires further exploration in the future.

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.

Utility of Stool-Based Tests for Colorectal Cancer Detection: A Comprehensive Review

Colorectal cancer (CRC) is a significant global health issue where early detection is crucial for improving treatment outcomes and survival rates. This comprehensive review assesses the utility of stool-based tests in CRC screening, including traditional fecal occult blood tests (FOBT), both chemical (gFOBT) and immunochemical techniques (FIT), as well as multitarget stool DNA (mt-sDNA) as a novel and promising biomarker. The advancements, limitations and the impact of false positives and negatives of these methods are examined. The review analyzed various studies on current screening methods, focusing on laboratory tests and biomarkers. Findings indicate that while FIT and mt-sDNA tests offer enhanced sensitivity and specificity over traditional guaiac-based FOBT, they also come with higher costs and potential for increased false positives. FIT shows better patient adherence due to its ease to use, but incorrect usage and interpretation of FOBT can lead to significant diagnostic errors. In conclusion, despite the improvements in FOBT methods like FIT in CRC detection, careful consideration of each method's benefits and drawbacks is essential. Effective CRC screening programs should combine various methods tailored to specific population needs, aiming for early detection and reduced mortality rates.

Trends in colorectal cancer surgical resection rates during the screening era: a retrospective study in Italy

BACKGROUND

Faecal immunochemical test (FIT)-based screening is effective in reducing colorectal cancer (CRC) incidence, but its sensitivity for proximal lesions remains low.

OBJECTIVES

We compared age-adjusted CRC surgical resection rates across anatomic sites (proximal colon, distal colon, rectum), age groups and sex over 20 years in a large Italian population. We particularly focused on changes in trends following FIT-screening implementation in the target population (50-69 years).

DESIGN

This retrospective study analysed data from the Veneto Region's administrative Hospital Discharge Dataset, involving over 54 000 patients aged 40-89 (43.4% female) who underwent CRC surgery between 2002 and 2021.

RESULTS

Overall, surgery rates increased until 2007 (annual percentage changes: 2.5% in males, 2.9% in females) and then declined (-4.2% in males, -3.4% in females). This decline was steeper for distal and rectal cancers compared with proximal cancer, suggesting a shift towards more right-sided CRC surgery.In males, the prescreening increase in proximal surgery was reversed after screening implementation (slope change: -6%) while the prescreening decline accelerated for distal (-4%) and rectal (-3%) surgeries. In females, stable prescreening trends shifted downward for all sites (-5% for proximal, -8% for distal and -7% for rectal surgery). However, the change in trends between prescreening and postscreening periods was not different across anatomic sites for either sex (all slope change differences in pairwise comparisons were not statistically significant).

CONCLUSION

The shift towards proximal surgery may not be entirely due to the FIT's low sensitivity but may reflect an underlying upward trend in proximal cancers independent of screening.

The Italian Unitary Society of Colon-Proctology (Società Italiana Unitaria di Colonproctologia) guidelines for the management of acute and chronic hemorrhoidal disease

The aim of these evidence-based guidelines is to present a consensus position from members of the Italian Unitary Society of Colon-Proctology (Società Italiana Unitaria di Colon-Proctologia, SIUCP) on the diagnosis and management of hemorrhoidal disease, with the goal of guiding physicians in the choice of the best treatment option. A panel of experts was charged by the Board of the SIUCP to develop key questions on the main topics related to the management of hemorrhoidal disease and to perform an accurate and comprehensive literature search on each topic, in order to provide evidence-based answers to the questions and to summarize them in statements. All the clinical questions were discussed by the expert panel in multiple rounds through the Delphi approach and, for each statement, a consensus among the experts was reached. The questions were created according to PICO (patients, intervention, comparison, and outcomes) criteria, and the statements were developed adopting the GRADE (Grading of Recommendations, Assessment, Development, and Evaluations) methodology. In cases of grade 1 hemorrhoidal prolapse, outpatient procedures including hemorrhoidal laser procedure and sclerotherapy may be considered the preferred surgical options. For grade 2 prolapse, nonexcisional procedures including outpatient treatments, hemorrhoidal artery ligation and mucopexy, laser hemorrhoidoplasty, the Rafaelo procedure, and stapled hemorrhoidopexy may represent the first-line treatment options, whereas excisional surgery may be considered in selected cases. In cases of grades 3 and 4, stapled hemorrhoidopexy and hemorrhoidectomy may represent the most effective procedures, even if, in the expert panel opinion, stapled hemorrhoidopexy represents the gold-standard treatment for grade 3 hemorrhoidal prolapse.

Socioeconomic differences in discrepancies between expected and experienced discomfort from colonoscopy and colon capsule endoscopy

Background

Social inequalities in colorectal cancer screening participation are evident. Barriers to screening participation include discomfort from diagnostic modalities. We aimed to describe the discomfort experienced from colonoscopy and colon capsule endoscopy (CCE) and investigate the discrepancy between expected and experienced discomfort stratified by socioeconomic status.

Methods

A randomised controlled trial was conducted offering half of the colorectal cancer screening invitees the choice between CCE and colonoscopy after a positive faecal immunochemical test. This paper includes those who elected to undergo CCE. A positive CCE elicited referral for a therapeutic colonoscopy. Participants reported their discomfort from CCE and from any following colonoscopies in electronically distributed questionnaires. Discomfort was measured using visual analogue scales and compared between socioeconomic subgroups determined by educational level and income.

Results

The experienced discomfort from CCE and colonoscopy differed significantly between educational levels but not income levels. The bowel preparation contributed the most to the experienced discomfort in both CCE and colonoscopy. The discrepancy between expected and experienced discomfort from colonoscopy increased with increasing educational and income levels. A similar trend was seen in CCE between educational levels but not income levels.

Conclusions

None of the results indicated a higher discomfort in lower socioeconomic subgroups. Regardless of the investigation modality, the bowel preparation was the main contributor to experienced discomfort. The discrepancy between expected and experienced discomfort did not seem to be larger in lower socioeconomic subgroups, indicating that this is not a major barrier causing inequalities in screening uptake. This is the first study investigating individual discomfort discrepancy in both CCE and colonoscopy, while being able to stratify by socioeconomic status.

The impact on clinical outcomes and healthcare resources from discontinuing colonoscopy surveillance subsequent to low-risk adenoma removal: A simulation study using the OncoSim-Colorectal model

OBJECTIVE

To estimate the impact on clinical outcomes and healthcare resource use from recommending that patients with 1-2 low-risk adenomas (LRAs) return to routine fecal immunochemical test (FIT) screening instead of surveillance colonoscopy, from a Canadian provincial healthcare system perspective.

METHODS

The OncoSim-Colorectal microsimulation model simulated average-risk individuals eligible for FIT-based colorectal cancer (CRC) screening in Alberta, Canada. We simulated two surveillance strategies that applied to individuals with 1-2 LRAs (<10 mm) removed as part of the average risk CRC screening program: (a) Surveillance colonoscopy (status quo) and (b) return to FIT screening (new strategy); both at 5 years after polypectomy. A 75 ng/mL FIT positivity threshold was used in the base case. The simulations projected average annual CRC outcomes and healthcare resource use from 2023 to 2042. We conducted alternative scenarios and sensitivity analyses on key variables.

RESULTS

Returning to FIT screening (versus surveillance colonoscopy) after polypectomy was projected to have minimal impact on long-term CRC incidence and deaths (not statistically significant). There was a projected decrease of one (4%) major bleeding event and seven (5%) perforation events per year. There was a projected increase of 4800 (1.5%) FIT screens, decrease of 3900 (5.1%) colonoscopies, and a decrease of $3.4 million (1.2%) in total healthcare costs per year, on average. The annual colonoscopies averted and healthcare cost savings increased over time. Results were similar in the alternative scenarios and sensitivity analyses.

CONCLUSIONS

Returning to FIT screening would have similar clinical outcomes as surveillance colonoscopy but could reduce colonoscopy demand and healthcare costs.

Colorectal cancer screening knowledge among community pharmacists: A national survey

BACKGROUND

Colorectal cancer (CRC) screening can reduce CRC morbidity and mortality. Community pharmacies could be a viable option for delivering home-based CRC screening tests such as fecal immunochemical tests (FITs). However, little is known about community pharmacists' knowledge about CRC screening guidelines.

OBJECTIVE

We assessed community pharmacists' knowledge about CRC screening to identify education and training needs for a pharmacy-based CRC screening program.

METHODS

Between September 2022 and January 2023, we conducted an online national survey of community pharmacists practicing in the United States. Responders were eligible if they were currently-licensed community pharmacists and currently practiced in the United States. The survey assessed knowledge of national CRC screening guidelines, including recommended starting age, frequency of screening, different screening modalities, and follow-up care. Using multiple linear regression, we evaluated correlates of community pharmacists' level of CRC screening knowledge, defined as the total number of knowledge questions answered correctly from "0" (no questions correct) to "5" (all questions correct).

RESULTS

A total of 578 eligible community pharmacists completed the survey, with a response rate of 59%. Most community pharmacists correctly answered the question about the next steps following a positive FIT (87%) and the question about where a FIT can be done (84%). A minority of community pharmacists responded correctly to questions about the age to start screening with FIT (34%) and how often a FIT should be repeated (28%). Only 5% of pharmacists answered all knowledge questions correctly. Community pharmacists answered more CRC screening knowledge questions correctly as their years in practice increased. Board-certified community pharmacists answered more CRC screening knowledge questions correctly compared to those who were not board-certified.

CONCLUSION

To ensure the successful implementation of a pharmacy-based CRC screening program, community pharmacists need to be educated about CRC screening and trained to ensure comprehensive patient counseling and preventive service delivery.

The association between organised colorectal cancer screening strategies and reduction of its related mortality: a systematic review and meta-analysis

BACKGROUND

To assess the long-term association between organised colorectal cancer (CRC) screening strategies and CRC-relate mortality.

METHODS

We systematically reviewed studies on organised CRC screening through PubMed, Ovid Medline, Embase and Cochrane from the inception. We retrieved characteristics of organised CRC screening from included literature and matched mortality (over 50 years) of those areas from the International Agency for Research on Cancer in May 2023. The variations of mortality were reported via the age-standardised mortality ratio. A random-effects model was used to synthesis results.

RESULTS

We summarised 58 organised CRC screening programmes and recorded > 2.7 million CRC-related deaths from 22 countries where rollout screening programmes were performed. The CRC screening strategy with faecal tests (guaiac faecal occult blood test (gFOBT) or faecal immunochemical tests (FIT)) or colonoscopy as the primary screening offer was associated with a 41.8% reduction in mortality, which was higher than those offered gFOBT (4.4%), FIT (16.7%), gFOBT or FIT (16.2%), and faecal tests (gFOBT or FIT) or flexible sigmoidoscopy (16.7%) as primary screening test. The longer duration of screening was associated with a higher reduction in the pooled age-standardised mortality ratio. In particular, the pooled age-standardised mortality ratio became non-significant when the screening of FIT was implemented for less than 5 years.

CONCLUSIONS

A CRC screening programme running for > 5 years was associated with a reduction of CRC-related mortality. Countries with a heavy burden of CRC should implement sustainable, organised screening providing a choice between faecal tests and colonoscopy as a preferred primary test.

Risk of Colorectal Cancer and Colorectal Cancer Mortality Beginning One Year after a Negative Fecal Occult Blood Test, among Screen-Eligible 76- to 85-Year-Olds

BACKGROUND

Colorectal cancer screening is universally recommended for adults ages 45 to 75 years. Noninvasive fecal occult blood tests are effective screening tests recommended by guidelines. However, empirical evidence to inform older adults' decisions about whether to continue screening is sparse, especially for individuals with prior screening.

METHODS

This study used a retrospective cohort of older adults at three Kaiser Permanente integrated healthcare systems (Northern California, Southern California, Washington) and Parkland Health. Beginning 1 year following a negative stool-based screening test, cumulative risks of colorectal cancer incidence, colorectal cancer mortality (accounting for deaths from other causes), and non-colorectal cancer mortality were estimated.

RESULTS

Cumulative incidence of colorectal cancer in screen-eligible adults ages 76 to 85 with a negative fecal occult blood test 1 year ago (N = 118,269) was 0.23% [95% confidence interval (CI), 0.20%-0.26%] after 2 years and 1.21% (95% CI, 1.13%-1.30%) after 8 years. Cumulative colorectal cancer mortality was 0.03% (95% CI, 0.02%-0.04%) after 2 years and 0.33% (95% CI, 0.28%-0.39%) after 8 years. Cumulative risk of death from non-colorectal cancer causes was 4.81% (95% CI, 4.68%-4.96%) after 2 years and 28.40% (95% CI, 27.95%-28.85%) after 8 years.

CONCLUSIONS

Among 76- to 85-year-olds with a recent negative stool-based test, cumulative colorectal cancer incidence and mortality estimates were low, especially within 2 years; death from other causes was over 100 times more likely than death from colorectal cancer.

IMPACT

These findings of low absolute colorectal cancer risk, and comparatively higher risk of death from other causes, can inform decision-making regarding whether and when to continue colorectal cancer screening beyond age 75 among screen-eligible adults.

Increasing the accuracy of colorectal cancer screening

INTRODUCTION

Colorectal cancer (CRC) is a major health issue, being responsible for nearly 10% of all cancer-related deaths. Since CRC is often an asymptomatic or paucisymptomatic disease until it reaches advanced stages, screening is crucial for the diagnosis of preneoplastic lesions or early CRC.

AREAS COVERED

The aim of this review is to summarize the literature evidence on currently available CRC screening tools, with their pros and cons, focusing on the level of accuracy reached by each test over time. We also provide an overview of novel technologies and scientific advances that are currently being investigated and that in the future may represent real game-changers in the field of CRC screening.

EXPERT OPINION

We suggest that best screening modalities are annual or biennial FIT and colonoscopy every 10 years. We believe that the introduction of artificial intelligence (AI)-tools in the CRC screening field could lead to a significant improvement of the screening efficacy in reducing CRC incidence and mortality in the future. More resources should be put into implementing CRC programmes and support research project to further increase accuracy of CRC screening tests and strategies.

Effectiveness of Colorectal Cancer (CRC) Screening on All-Cause and CRC-Specific Mortality Reduction: A Systematic Review and Meta-Analysis

(1) Background: The aim of this study was to pool and compare all-cause and colorectal cancer (CRC) specific mortality reduction of CRC screening in randomized control trials (RCTs) and simulation models, and to determine factors that influence screening effectiveness. (2) Methods: PubMed, Embase, Web of Science and Cochrane library were searched for eligible studies. Multi-use simulation models or RCTs that compared the mortality of CRC screening with no screening in general population were included. CRC-specific and all-cause mortality rate ratios and 95% confidence intervals were calculated by a bivariate random model. (3) Results: 10 RCTs and 47 model studies were retrieved. The pooled CRC-specific mortality rate ratios in RCTs were 0.88 (0.80, 0.96) and 0.76 (0.68, 0.84) for guaiac-based fecal occult blood tests (gFOBT) and single flexible sigmoidoscopy (FS) screening, respectively. For the model studies, the rate ratios were 0.45 (0.39, 0.51) for biennial fecal immunochemical tests (FIT), 0.31 (0.28, 0.34) for biennial gFOBT, 0.61 (0.53, 0.72) for single FS, 0.27 (0.21, 0.35) for 10-yearly colonoscopy, and 0.35 (0.29, 0.42) for 5-yearly FS. The CRC-specific mortality reduction of gFOBT increased with higher adherence in both studies (RCT: 0.78 (0.68, 0.89) vs. 0.92 (0.87, 0.98), model: 0.30 (0.28, 0.33) vs. 0.92 (0.51, 1.63)). Model studies showed a 0.62-1.1% all-cause mortality reduction with single FS screening. (4) Conclusions: Based on RCTs and model studies, biennial FIT/gFOBT, single and 5-yearly FS, and 10-yearly colonoscopy screening significantly reduces CRC-specific mortality. The model estimates are much higher than in RCTs, because the simulated biennial gFOBT assumes higher adherence. The effectiveness of screening increases at younger screening initiation ages and higher adherences.

The Use of a Non-Invasive Biomarker for Colorectal Cancer Screening: A Comparative Cost-Effectiveness Modeling Study

This study aimed to examine the cost-effectiveness of fecal biomarker M3 panel compared to fecal immunochemical test (FIT) and colonoscopy in an Asian population. In a hypothetical population of 100,000 persons aged 50 years who received FIT yearly, M3 biomarker yearly, or colonoscopy every 10 years until the age of 75 years. Participants with positive FOBT or a result of "high risk" identified using the M3 biomarker are offered colonoscopy. We assumed surveillance colonoscopy is repeated every 3 years, and examined the treatment cost. A comparison of various outcome measures was conducted using Markov modelling. The incremental cost-effectiveness ratio (ICER) of FIT, M3 biomarker, and colonoscopy was USD108,176, USD133,485 and USD159,596, respectively. Comparing with FIT, the use of M3 biomarker could lead to significantly smaller total loss of cancer-related life-years (2783 vs. 5279); a higher number of CRC cases prevented (1622 vs. 146), a higher proportion of CRC cases prevented (50.2% vs. 4.5%), more life-years saved (2852 vs. 339), and cheaper total costs per life-year saved (USD212,553 vs. 773,894). The total costs per life-year saved is more affordable than that achieved by colonoscopy as a primary screening tool (USD212,553 vs. USD236,909). The findings show that M3 biomarkers may be more cost-effective than colonoscopy.

Machine Learning in Colorectal Cancer Risk Prediction from Routinely Collected Data: A Review

The inclusion of machine-learning-derived models in systematic reviews of risk prediction models for colorectal cancer is rare. Whilst such reviews have highlighted methodological issues and limited performance of the models included, it is unclear why machine-learning-derived models are absent and whether such models suffer similar methodological problems. This scoping review aims to identify machine-learning models, assess their methodology, and compare their performance with that found in previous reviews. A literature search of four databases was performed for colorectal cancer prediction and prognosis model publications that included at least one machine-learning model. A total of 14 publications were identified for inclusion in the scoping review. Data was extracted using an adapted CHARM checklist against which the models were benchmarked. The review found similar methodological problems with machine-learning models to that observed in systematic reviews for non-machine-learning models, although model performance was better. The inclusion of machine-learning models in systematic reviews is required, as they offer improved performance despite similar methodological omissions; however, to achieve this the methodological issues that affect many prediction models need to be addressed.

Risk of Colorectal Cancer and Colorectal Cancer Mortality Beginning Ten Years after a Negative Colonoscopy, among Screen-Eligible Adults 76 to 85 Years Old

BACKGROUND

Few empirical data are available to inform older adults' decisions about whether to screen or continue screening for colorectal cancer based on their prior history of screening, particularly among individuals with a prior negative exam.

METHODS

Using a retrospective cohort of older adults receiving healthcare at three Kaiser Permanente integrated healthcare systems in Northern California (KPNC), Southern California (KPSC), and Washington (KPWA), we estimated the cumulative risk of colorectal cancer incidence and mortality among older adults who had a negative colonoscopy 10 years earlier, accounting for death from other causes.

RESULTS

Screen-eligible adults ages 76 to 85 years who had a negative colonoscopy 10 years earlier were found to be at a low risk of colorectal cancer diagnosis, with a cumulative incidence of 0.39% [95% CI, 0.31%-0.48%) at 2 years that increased to 1.29% (95% CI, 1.02%-1.61%) at 8 years. Cumulative mortality from colorectal cancer was 0.04% (95% CI, 0.02%-0.08%) at 2 years and 0.46% (95% CI, 0.30%-0.70%) at 8 years.

CONCLUSIONS

These low estimates of cumulative colorectal cancer incidence and mortality occurred in the context of much higher risk of death from other causes.

IMPACT

Knowledge of these results could bear on older adults' decision to undergo or not undergo further colorectal cancer screening, including choice of modality, should they decide to continue screening. See related commentary by Lieberman, p. 6.

Gut microbiome in tumorigenesis and therapy of colorectal cancer

Colorectal cancer (CRC) is the malignant tumor with the highest incidence in the digestive system, and the gut microbiome plays a crucial role in CRC tumorigenesis and therapy. The gastrointestinal tract is the organ harboring most of the microbiota in humans. Changes in the gut microbiome in CRC patients suggest possible host-microbe interactions, thereby hinting the potential tumorigenesis, which provides new perspective for preventing, diagnosing, or treating CRC. In this review, we discuss the effects of gut microbiome dysbiosis on CRC, and reveal the mechanisms by which gut microbiome dysbiosis leads to CRC. Gut microbiome modulation with the aim to reverse the established gut microbial dysbiosis is a novel strategy for the prevention and treatment of CRC. In addition, this review summarizes that probiotic antagonize CRC tumorigenesis by protecting intestinal barrier function, inhibiting cancer cell proliferation, resisting oxidative stress, and enhancing host immunity. Finally, we highlight clinical applications of the gut microbiome, such as gut microbiome analysis-based biomarker screening and prediction, and microbe modulation-based CRC prevention, treatment enhancement, and treatment side effect reduction. This review provides the reference for the clinical application of gut microbiome in the prevention and treatment of CRC.

Colorectal cancer and gut microbiota studies in China

Colorectal cancer (CRC) is the third most common malignant tumor worldwide. The incidence and mortality rates of CRC have been increasing in China, possibly due to economic development, lifestyle, and dietary changes. Evidence suggests that gut microbiota plays an essential role in the tumorigenesis of CRC. Gut dysbiosis, specific pathogenic microbes, metabolites, virulence factors, and microbial carcinogenic mechanisms contribute to the initiation and progression of CRC. Gut microbiota biomarkers have potential translational applications in CRC screening and early diagnosis. Gut microbiota-related interventions could improve anti-tumor therapy's efficacy and severe intestinal toxic effects. Chinese researchers have made many achievements in the relationship between gut microbiota and CRC, although some challenges remain. This review summarizes the current evidence from China on the role of gut microbiota in CRC, mainly including the gut microbiota characteristics, especially Fusobacterium nucleatum and Parvimonas micra, which have been identified to be enriched in CRC patients; microbial pathogens such as F. nucleatum and enterotoxigenic Bacteroides fragilis, and P. micra, which Chinese scientists have extensively studied; diagnostic biomarkers especially F. nucleatum; therapeutic effects, including microecological agents represented by certain Lactobacillus strains, fecal microbiota transplantation, and traditional Chinese medicines such as Berberine and Curcumin. More efforts should be focused on exploring the underlying mechanisms of microbial pathogenesis of CRC and providing novel gut microbiota-related therapeutic and preventive strategies.

Clinical Effectiveness of Faecal Immunochemical Test in the Early Detection of Colorectal Cancer-An Umbrella Review

Introduction: The colorectal cancer prognosis depends on the stage of the neoplasm; therefore, its early detection plays an important role. The aim of the study is evaluation of the sensitivity, specificity, and clinical effectiveness of the faecal immunochemical test in the early colorectal cancer detection. Methods: The clinical analysis was based on the results of the studies included in a systematic review conducted in accordance with the Cochrane Collaboration guidelines. The following medical information sources were searched: Medline (via PubMed), Embase (via Ovid), The Cochrane Library. Results: From 241 citations, 13 studies were included in this review. All included studies had a low risk of bias. The faecal immunochemical test is highly specific in all analysed populations ranging from 85% to 97%. In most of the found studies, sensitivity is over 75%. The faecal immunochemical test screening also determines a reduction in death (10-59%) due to colorectal cancer. Conclusions: The faecal immunochemical test is an effective and cost-effective method of conducting population-wide colorectal cancer screening. It is an alternative or complementary to other screening tests, including colonoscopy.

Detection and Yield of Colorectal Cancer Surveillance in Adults with PTEN Hamartoma Tumour Syndrome

Colorectal cancer surveillance (CCS) with colonoscopy every five years is advised for PTEN Hamartoma Tumour Syndrome (PHTS) patients aged ≥40 due to an increased colorectal cancer (CRC) risk. However, data to support CCS guidelines are scarce and available CRC risks are low (0-5% at age 50) and likely overestimated. We aimed to assess the detection and yield of CCS for PHTS patients without a CRC history. A retrospective cohort study including PHTS patients aged ≥40 with CCS at a PHTS expertise centre between 2011 and 2022. Adenomas with a ≥10 mm size, (tubulo)villous histology, or high-grade dysplasia were considered advanced. During 67 follow-up years, 37 patients (median age 47 years) underwent 61 colonoscopies. CCS yielded no CRCs. Adenomas were diagnosed in 13/37 (35%) patients during 23/100 colonoscopies (95% CI: 14-36), including one advanced adenoma. Baseline adenoma detection rates were similar to follow-up and higher in patients aged above 50 (50/100, 95% CI: 24-76) vs. age 50 or below (11/100, 95% CI: 3-30; p = 0.021). The low CRC and advanced adenoma yield allow for a more personalised surveillance program. Following our findings combined with literature on CRC risk and progression, we suggest starting CCS at age 40 with variable follow-up intervals between 1 and 10 years depending on previous colonoscopy findings.

Feasibility of quantification based on novel evaluation with stool DNA and fecal immunochemical test for colorectal cancer detection

Background

Stool DNA (sDNA) tests and fecal immunochemical test (FIT) are used for the detection of colorectal cancer (CRC). Here we performed a novel evaluation using sDNA and FIT to assess their performance in CRC screening and monitoring in Hubei, China.

Methods

Stool samples were collected from a high-risk population in Hubei, China (n = 359). sDNA tests and FIT were performed to test for KRAS mutations, NDRG4 and BMP3 methylation, and check hemoglobin levels. The methylation in BMP3 and NDRG4 genes was detected by TaqMan PCR method from human fecal samples. KRAS gene mutation in human fecal DNA was tested using TaqMan probe and amplification-refractory mutation system method. The colloid gold method was used for detection of hemoglobin in fecal samples. Finally, a novel evaluation by software was used to calculate the comprehensive value of the combined results for CRC detection and monitoring.

Results

The sensitivity and specificity of the novel evaluation for early CRC (stage I and II), advanced adenoma (AA), and non-colon cancer neoplasm (NA) detection were 95.45% and 81.6%, 29.63% and 75.9%, and 23.08% and 75.17%, respectively. The receiver operating characteristic (ROC) curves of the combined value for the above diseases were 0.945 ± 0.015, 0.543 ± 0.055, and 0.547 ± 0.038, respectively. The levels of the novel evaluation were not significantly associated with the pathology and stage (P > 0.05). In 20 out of 22 CRC patients, the novel evaluation of sDNA and FIT had decreased below threshold (< 165) at after surgery.

Discussion

The novel evaluation with sDNA test and FIT has increased sensitivity for screening of CRC and AA. The novel evaluation may have potential importance as an indicator of early CRC. Additionally, the dynamic changes of the comprehensive value after surgery were correlated with CRC treatment.

Awareness and Knowledge of Colorectal Cancer Screening Among Medical Students at the University of Aleppo: A Cross-Sectional Study

Background  Colorectal cancer (CRC) is the third leading cause of malignancy in Syria. The aim of our study was to assess the awareness and knowledge of CRC and its screening methods among medical students at the University of Aleppo.

Methods  A cross-sectional study of medical students at the University of Aleppo was conducted using a self-administered 12-element questionnaire. The questionnaire consisted of demographics, awareness of CRC, knowledge of CRC and its screening methods. Awareness of CRC included three questions asking students if they ever heard of CRC and its screening methods. Knowledge of CRC was evaluated through three sets of questions about CRC risk factors, signs and symptoms, and preventative methods. The students were selected randomly during academic lectures. A χ² or Fisher's exact tests for categorical variables were used for statistical analysis, as appropriate. A two-sided p  < 0.05 was considered statistically significant. We stratified students based on pre-clinical versus clinical years and average academic score.

Results  A total of 824 students completed the questionnaire. The majority of students were aware of CRC (98.9%) and CRC screening methods (79.8%). Students had poor knowledge of CRC risk factors (16.5% for non-modifiable factors and 11.7% for modifiable factors), signs and symptoms (52.6%), and protective factors (9.9%). Only 31.7% of students were able to identify the appropriate age to initiate screening for average-risk individuals. Clinical students had better awareness and knowledge of CRC and its screening methods. Clinical students with higher academic score showed better awareness and knowledge in some elements.

Conclusion  Our study reported high awareness and poor knowledge rates of CRC and its screening methods among medical students at the University of Aleppo. Although clinical students had higher awareness and knowledge of CRC compared to pre-clinical students, the impact of academic score revealed variable results.

The role of gut microbiota in the development of colorectal cancer: a review

PURPOSE

Colorectal cancer (CRC) is the cancer of the colon and rectum. Recent research has found a link between CRC and human gut microbiota. This review explores the effect of gut microbiota on colorectal carcinogenesis and the development of chemoresistance.

METHODS

A literature overview was performed to identify the gut microbiota species that showed altered abundance in CRC patients and the mechanisms by which some of them aid in the development of chemoresistance.

RESULTS

Types of gut microbiota present and methods of analyzing them were discussed. We observed that numerous microbiota showed altered abundance in CRC patients and could act as a biomarker for CRC diagnosis and treatment. Further, it was demonstrated that microbes also have a role in the development of chemoresistance by mechanisms like immune system activation, drug modification, and autophagy modulation. Finally, the key issue of the growing global problem of antimicrobial resistance and its relationship with CRC was highlighted.

CONCLUSION

This review discussed the role of gut microbiota dysbiosis on colorectal cancer progression and the development of chemoresistance.

Identifying the factors promoting colorectal cancer screening uptake in Hong Kong using Andersen's behavioural model of health services use

Background

Colorectal cancer (CRC) screening is an effective strategy to aid early cancer detection. However, the decision to undergo screening can be affected by a variety of factors. The aims of this study were to examine current CRC screening uptake in Hong Kong and identify the factors associated with it using Andersen’s Behavioural Model as a guiding framework.

Methods

This cross-sectional study was conducted in Hong Kong from August 2019 to December 2020. A sample of 1317 Chinese individuals aged 50 to 75 years were recruited and completed a survey to identify predisposing, enabling, and need-for-care factors, and the colorectal cancer screening uptake rate (faecal occult blood test [FOBT] or faecal immunochemical test [FIT] and colonoscopy) was determined.

Results

The FOBT/FIT uptake rate was 43.9%, while that of the colonoscopy was 26.0%. The provision of a government subsidy for screening and the provision of information booklets were the most significant and second most significant enabling factors for FOBT/FIT uptake, respectively. Visiting a doctor five times or more in the previous year and being recommended to undergo a CRC screening by a doctor, were the most significant enabling factors for colonoscopy uptake. Age, the perceived benefit of and barriers to screening were important predisposing factors for FOBT/FIT and colonoscopy uptake.

Conclusions

Screening uptake rates in Hong Kong have significantly increased over the last decade, although they remain lower than those in other countries. Continual efforts are warranted to promote government-subsidised screening. Relevant educational materials that address the barriers identified in this study should be developed and disseminated to the public.

Screening for Colorectal Cancer

Colorectal cancer (CRC) is the second-leading cause of cancer death in the United States. Screening reduces CRC incidence and mortality. 2021 US Preventive Service Task Force (USPSTF) guidelines and available evidence support routine screening from ages 45 to 75, and individualized consideration of screening ages 76 to 85. USPSTF guidelines recommend annual guaiac fecal occult blood testing, annual fecal immunochemical testing (FIT), annual to every 3-year multitarget stool DNA-FIT, every 5-year sigmoidoscopy, every 10-year sigmoidoscopy with annual FIT, every 5-year computed tomographic colonography, and every 10-year colonoscopy as options for screening. The "best test is the one that gets done."

One or two faecal immunochemical tests in an organised population-based colorectal cancer screening programme in Murcia (Spain)

OBJECTIVE

Roll-out of population-based colorectal cancer (CRC) screening with faecal immunochemical test (FIT) is limited by availability of further investigations, particularly colonoscopy and examination of excised lesions. Our objective was to assess whether variation in number of faecal samples and threshold adjustment can optimise resource utilisation and CRC detection rate.

METHODS

Three different screening strategies were compared for the same FIT threshold using a quantitative FIT system: one FIT, positive when >20 µg Hb/g faeces; two FIT, positive when either was >20 µg Hb/g faeces; and two FIT, positive when the mean was >20 µg Hb/g faeces. We calculated changes in the size of population the provider could invite to screening for an equal number of screening positive results, and CRC and adenoma detected.

RESULTS

In our setting, Region of Murcia, south of Spain (not fully rolled out screening programme), changing the usual strategy of two FIT, positive when either to positive when the mean was >20 µg Hb/g faeces, would increase population invited by 37.81% with the same number of positive results (which would generate a CRC detection rate of 19.2%). In a fully rolled out programme, changing the strategy from one to two FIT (positive when the mean is >20 µg Hb/g faeces), would increase CRC detection rate by 4.64% with an increase of only 13.34% in positive FIT.

CONCLUSIONS

In a population-based CRC screening programme, smart use of number of FITs and positivity threshold can increase population invited and CRC detection without increasing the number of colonoscopies and pathological examinations needed.

Polygenic risk prediction models for colorectal cancer: a systematic review

BACKGROUND

Risk prediction models incorporating single nucleotide polymorphisms (SNPs) could lead to individualized prevention of colorectal cancer (CRC). However, the added value of incorporating SNPs into models with only traditional risk factors is still not clear. Hence, our primary aim was to summarize literature on risk prediction models including genetic variants for CRC, while our secondary aim was to evaluate the improvement of discriminatory accuracy when adding SNPs to a prediction model with only traditional risk factors.

METHODS

We conducted a systematic review on prediction models incorporating multiple SNPs for CRC risk prediction. We tested whether a significant trend in the increase of Area Under Curve (AUC) according to the number of SNPs could be observed, and estimated the correlation between AUC improvement and number of SNPs. We estimated pooled AUC improvement for SNP-enhanced models compared with non-SNP-enhanced models using random effects meta-analysis, and conducted meta-regression to investigate the association of specific factors with AUC improvement.

RESULTS

We included 33 studies, 78.79% using genetic risk scores to combine genetic data. We found no significant trend in AUC improvement according to the number of SNPs (p for trend = 0.774), and no correlation between the number of SNPs and AUC improvement (p = 0.695). Pooled AUC improvement was 0.040 (95% CI: 0.035, 0.045), and the number of cases in the study and the AUC of the starting model were inversely associated with AUC improvement obtained when adding SNPs to a prediction model. In addition, models constructed in Asian individuals achieved better AUC improvement with the incorporation of SNPs compared with those developed among individuals of European ancestry.

CONCLUSIONS

Though not conclusive, our results provide insights on factors influencing discriminatory accuracy of SNP-enhanced models. Genetic variants might be useful to inform stratified CRC screening in the future, but further research is needed.

Circulating tumor cells in colorectal cancer in the era of precision medicine

Colorectal cancer (CRC) is one of the main causes of cancer-related morbidity and mortality across the globe. Although serum biomarkers such as carcinoembryonic antigen (CEA) and carbohydrate antigen 19–9 (CA-199) have been prevalently used as biomarkers in various cancers, they are neither very sensitive nor highly specific. Repeated tissue biopsies at different times of the disease can be uncomfortable for cancer patients. Additionally, the existence of tumor heterogeneity and the results of local biopsy provide limited information about the overall tumor biology. Against this backdrop, it is necessary to look for reliable and noninvasive biomarkers of CRC. Circulating tumor cells (CTCs), which depart from a primary tumor, enter the bloodstream, and imitate metastasis, have a great potential for precision medicine in patients with CRC. Various efficient CTC isolation platforms have been developed to capture and identify CTCs. The count of CTCs, as well as their biological characteristics and genomic heterogeneity, can be used for the early diagnosis, prognosis, and prediction of treatment response in CRC. This study reviewed the existing CTC isolation techniques and their applications in the clinical diagnosis and treatment of CRC. The study also presented their limitations and provided future research directions.

Characteristics of colorectal cancers among Alaska Native people before and after implementing programs to promote screening

BACKGROUND

Alaska Native (AN) people have the highest rates of colorectal cancer (CRC) globally. Increasing CRC screening has been effective in reducing CRC-related morbidity and mortality in other populations.

OBJECTIVE

To examine recent descriptive epidemiology and longer-term CRC trends among AN people. To determine any changes in the descriptive epidemiology of CRC among AN people concurrent with increases in screening prevalence.

METHODS

We estimated age-specific CRC incidence and mortality rates 2000-2017. To examine longer-term trends in incidence and mortality 1990-2017, we conducted Joinpoint regression analyses of three-year rolling average incidence and mortality rates. We calculated descriptive statistics for two time-periods: 2000-2008, and 2009-2017. Finally, we examined five-year survival probability.

RESULTS

CRC incidence increased over time (1990-2017) among AN people aged less than 50 years, while there were modest declines in AN people older than 50 years old since 2000. Overall, AN CRC mortality rates declined between 1990 and 2004, but have been increasing steadily since that time. Comparing 2000-2008 with 2009-2017 we observed no difference in CRC incidence and mortality, age at diagnosis, tumor size, tumor location, or stage distribution. Survival analyses indicated no change in hazard of death between 2004-2008 and 2009-2017 (HR 1.02, 95 % CI: 0.74, 1.38, P = 0.93).

CONCLUSIONS

Colorectal cancer prevention and control efforts across the Alaska Tribal Health System have not yet resulted in reduced mortality rates, or induced earlier stage migration.

POLICY SUMMARY STATEMENT

Intensified efforts will be necessary to reduce the burden of CRC among this high-risk population. Continued and increased focus on primary and secondary prevention efforts is warranted.

Identification of ZNF26 as a Prognostic Biomarker in Colorectal Cancer by an Integrated Bioinformatic Analysis

The dysregulation of transcriptional factors (TFs) leads to malignant growth and the development of colorectal cancer (CRC). Herein, we sought to identify the transcription factors relevant to the prognosis of colorectal cancer patients. We found 526 differentially expressed TFs using the TCGA database of colorectal cancer patients (n = 544) for the differential analysis of TFs (n = 1,665) with 210 upregulated genes as well as 316 downregulated genes. Subsequently, GO analysis and KEGG pathway analysis were performed for these differential genes for investigating their pathways and function. At the same time, we established a genetic risk scoring model for predicting the overall survival (OS) by using the mRNA expression levels of these differentially regulated TFs, and defined the CRC into low and high-risk categories which showed significant survival differences. The genetic risk scoring model included four high-risk genes (HSF4, HEYL, SIX2, and ZNF26) and two low-risk genes (ETS2 and SALL1), and validated the OS in two GEO databases (p = 0.0023 for the GSE17536, p = 0.0193 for the GSE29623). To analyze the genetic and epigenetic changes of these six risk-related TFs, a unified bioinformatics analysis was conducted. Among them, ZNF26 is progressive in CRC and its high expression is linked with a poor diagnosis as well. Knockdown of ZNF26 inhibits the proliferative capacity of CRC cells. Moreover, the positive association between ZNF26 and cyclins (CDK2, CCNE2, CDK6, CHEK1) was also identified. Therefore, as a novel biomarker, ZNF26 may be a promising candidate in the diagnosis and prognostic evaluation of colorectal cancer.

Health literacy and cancer screening behaviors among community-dwelling female adults in Taiwan

This study was designed to explore the association among health literacy and cancer screening behaviors in Taiwanese females. A total of 353 community-dwelling females were recruited in this cross-sectional study from February to October 2015. Demographic, socioeconomic and personal behavior variables including physical activity, community activity, smoking, alcohol consumption, and betel nut chewing were recorded. Health literacy was evaluated using the Mandarin version of the European Health Literacy Survey Questionnaire. Data on screening behaviors for cervical, breast and colorectal cancers were confirmed by the Taiwanese National eHealth Database. Most respondents with inadequate or problematic general health literacy had no or irregular screening behaviors for cervical, breast and colorectal cancers. In multivariable regression analysis, women with inadequate health literacy were at a greater risk (Odds ratio = 5.71; 95% CI: 1.40-23.26) of having no previous Pap smear screening or >3 years screening interval regardless of education level. However, this association was not detected for breast or colorectal cancer. Women with inadequate health literacy were more likely to have irregular cervical cancer screening, however no associations among health literacy and breast or colorectal cancer were detected. The impact of health literacy on cancer screening behavior warrants further attention and research.

Intention for Screening Colonoscopy among Previous Non-Participants: Results of a Representative Cross-Sectional Study in Germany

Early detection of colorectal cancer has the potential to reduce mortality at population level. Colonoscopy is the preferred modality for colon cancer screening and prevention, but attendance rates are low. To exploit colonoscopy's preventive potential, it is necessary to identify the factors influencing uptake, especially among previous non-participants. This analysis of cross-sectional data involved 936 non-participants in screening colonoscopy aged 55 years or older in Germany. Differences between non-participants with and without future participation intentions were investigated in terms of socio-demographic factors, health status, attitudes and beliefs, and medical counselling. Logistic regression models were fitted to estimate associations between intention to participate and selected factors. Intention to participate was lower among women than among men. For both genders, intention to participate was positively associated with younger age. For women, higher socioeconomic status and counselling were positively associated with intention to participate. Men showed a positive association with favouring joint decision-making. The results draw attention to starting points for improving acceptance of and participation in screening colonoscopy. This includes good medical counselling and successful physician-patient communication, for which the information and communication skills of both medical professions and the general public should be strengthened. Gender differences should be considered.

Symptom Perceptions and Help-Seeking Behaviours of Omani Patients Diagnosed with Late-Stage Colorectal Cancer: A Qualitative Study

OBJECTIVE

Colorectal cancer (CRC) is the fourth leading cause of mortality in Oman, with most patients diagnosed at advanced stages. Early diagnosis of CRC improves prognosis and survival rate. The aim of this study was to explore the symptom perceptions and help-seeking behaviours (HSBs) of Omani patients diagnosed with late-stage CRC.

METHODS

Semi-structured individual interviews were conducted with 16 patients.

RESULTS

Four main themes emerged, including normalisation and ignorance (patients felt healthy, perceived symptoms as not being serious and related to dietary habits, concealed them or prioritised work and family commitments), self-empowerment and self-management (patients were stubborn, employed 'wait and see' approach, used symptomatic or herbal treatments), disclosure and seeking help (patients disclosed symptoms to family members or friends, sought medical help only when symptoms worsened, visited faith healers or travelled abroad for treatment) and healthcare professionals (patients attributed treatment or diagnosis delays to lack of continuity of care, loss of trust in doctors or delays in referral).

CONCLUSION

Patients attributed delays in CRC diagnosis to several factors based on their perceptions of symptoms. Most HSBs driven by sociocultural and emotional causes. Increased awareness of CRC symptoms and modifying HSBs can encourage early diagnosis. Prompting patients to disclose CRC-related symptoms may aid referral decisions.

Estimating the preferences and willingness-to-pay for colorectal cancer screening: an opportunity to incorporate the perspective of population at risk into policy development in Thailand

AIMS

Colorectal cancer (CRC) is one of the public health burdens that can be lowered by early detection. This study aims to examine the preferences and willingness-to-pay of a population at risk for CRC screening in Thailand. Understanding the preferences for these individuals at risk would help Thailand, as an example of LMICs, to design effective population-based CRC screening programs.

MATERIALS AND METHODS

A discrete choice experiment (DCE) was conducted among screening-naïve adults aged 50-75 years, who were at risk of CRC, in the out-patient department of a tertiary care hospital in Thailand. A DCE questionnaire was developed from six CRC screening attributes. Each questionnaire was composed of six choice sets and each contained two alternatives described by the different levels of attributes and an opt-out alternative. Participants were asked to choose one alternative from each choice set. A multinomial logit model was developed to determine the relative preference of each attribute. The willingness-to-pays for all attributes and screening modalities and the estimated preferred choices of the annual fecal immunochemical test (FIT), 10-yearly colonoscopy, 5-yearly double-contrast barium enema (DCBE), 5-yearly computed tomographic colonography (CTC), 5-yearly flexible sigmoidoscopy (FS), and no screening was calculated and compared.

RESULTS

Four hundred participants were included. All attributes, except pain and less bowel preparation, were statistically associated with the participants' preference (p < .05). They preferred screenings with a high-risk reduction of CRC-related mortality, no complication, 5-year interval, and lower cost. The estimated preferred choices of FIT, colonoscopy, DCBE, CTC, and FS were 38.2%, 11.4%, 14.6%, 9.2%, and 11.4%, respectively. The willingness-to-pays for each screening modality was US$251, US$189, US$183, US$154, and US$142 (8,107, 6,105, 5,911, 4,974, and 4,587 THB) per episode, respectively.

CONCLUSIONS

The risk reduction of CRC-related mortality, complication, screening interval, and cost influenced the CRC screening preferences of Thai adults. FIT was the most preferred. Policymakers can develop a successful CRC screening campaign using these findings, incorporating the perspective of the population at risk in policy formulation to accomplish their goals.

The Direct and Indirect Costs of Colorectal Cancer in Vietnam: An Economic Analysis from a Social Perspective

The incidence and mortality of colorectal cancer (CRC) has increased rapidly in Vietnam, but the economic burden of this disease has never been estimated. We estimate the direct and indirect cost of CRC patients in Vietnam in 2018 using a prevalence-based approach and human capital method. The total economic cost of CRC was VND 3041.88 billion (~$132.9 million), representing 0.055% of the 2018 gross domestic product. Notably, indirect costs comprised 83.58 % of the total cost, 82.61% of which is future income loss, because CRC occurs during productive years. The economic burden of CRC in Vietnam is substantial. The medical cost for CRC diagnosis and treatment is higher for younger patients and for those in advanced stages. Strategies to decrease the economic burden of CRC at the patient and national level, such as screening programs, should be developed and implemented in Vietnam.

Trends in incidence, mortality rates, and survival of colorectal cancer in Western Australia from 1990 to 2014: a retrospective whole-population longitudinal study

PURPOSE

This study aimed to investigate the trends in colorectal cancer (CRC) incidence and mortality rates among the Western Australian (WA) population. This study further compared the trends with the timing of the implementation and rollout of the National Bowel Cancer Screening Program (NBCSP) and examined the survival predictors in CRC cases.

METHODS

This study was a whole-population, retrospective longitudinal study and included all individuals with a confirmed histological diagnosis of primary invasive CRC diagnosed in WA from 1990 to 2014 (n = 25,932). The temporal trends were assessed by Joinpoint regression models and Kaplan-Meier survival curves were used to asses 5-year survival. Predictors of survival were examined using multivariable Cox proportional hazard regression models, adjusting for age of diagnosis.

RESULTS

The overall CRC incidence showed an upward trend between 1990 and 2010 (annual percent change (APC) = 1.1%); then, there was a downward trend from 2010 to 2014 (APC = - 5.0%). In younger people (< 50 years), the incidence rate increased steadily (APC = 0.9%) over the study period. The overall CRC mortality trend increased from 1990 to 1999 (APC = 1.6%), decreasing after that (APC = - 2.1%). Younger people had better CRC-related 5-year survival than older people (HR = 0.81, 95%CI 0.75-0.87, p = < 0.001).

CONCLUSION

This study found that CRC incidence and mortality rates decreased among older people over the last 10 years in Western Australia. However, incidence continues to rise for younger people. Hence, more widespread adoption of the screening program, and potential preventive and early diagnostic strategies should become key priorities for the CRC control in WA.

Pilot study of the effect of gastrointestinal diets on fecal occult blood testing in cats

OBJECTIVES

The aim of this study was to assess the methodology of guaiac-based fecal occult blood (FOB) testing in healthy cats, and to examine the effect of feeding selected gastrointestinal diets (canned and dry) on FOB results.

METHODS

Stool obtained from three cats was mixed with incremental quantities of EDTA whole blood. FOB tests were performed in triplicate and interpreted at 5 mins, and at 24, 48 and 72 h post-test set-up. Ten cats were fed their normal diets, a dry hydrolyzed protein diet, a dry gastrointestinal diet and then transitioned back to their normal diet over a 7-week period. A subsequent study was repeated with similar hydrolyzed protein and gastrointestinal canned diets. Two fecal samples were tested per cat each week using human point-of-care guaiac tests.

RESULTS

Ten microliters of whole feline blood could be reliably detected in feline stool at all time points evaluated. There was no evidence of an association between the dry hydrolyzed and dry gastrointestinal diets and a positive FOB test result (P = 0.33). Cats fed a canned gastrointestinal diet had a significantly higher probability of producing a positive FOB result than when on their normal diet (P <0.01). Feeding the canned hydrolyzed diet was not associated with an increased probability of a positive FOB test vs the normal diet (P = 0.94).

CONCLUSIONS AND RELEVANCE

Small amounts of blood in feline stool can be reliably and repeatedly detected as early as 5 mins post-FOB test set-up, making this a user-friendly bench-top screening test in a veterinary setting. Cats fed a single dry hydrolyzed, dry gastroenteric or canned hydrolyzed diet in this study had a low chance of false-positive FOB test results, while those fed the canned gastrointestinal diet had a significantly greater likelihood of producing false-positive results.

Colorectal Cancer Screening Decisions in the Opportunistic Setting

Colorectal cancer incidence and mortality have decreased in the United States in recent decades, largely through opportunistic screening. Although certain organizations have improved internal screening rates by implementing programmatic screening, most of the United States undergoes opportunistic screening. Much effort and resources have been expended comparing screening tests to determine the most effective; however, deeper analysis of the US population has revealed subsets of ethnicities may be grossly underscreened. The most effective screening test remains the test that is completed and adhered to, and a better question may concern the best method of discussing screening.

The association between health literacy and colorectal cancer screening uptake in a publicly funded screening program in Denmark: Cross-sectional study

There are multiple reasons for not participating in colorectal cancer screening, but the role of health literacy in screening uptake is not well understood. The aims of this study were to determine the association between health literacy and colorectal cancer screening uptake and to explore whether socioeconomic and -demographic characteristics and worry and attitude variables modify this association. In a cross-sectional study, 10,030 53-74-year-old randomly selected citizens resident in Central Denmark Region received a questionnaire assessing health literacy using the European Health Literacy Survey Short Scale 16-item. Data on colorectal cancer screening uptake were obtained from the Danish Colorectal Cancer Screening database, and socioeconomic and -demographic data were linked from Statistics Denmark. The response rate was 71% (n = 7142). Odds ratio (OR) for uptake was 1.06 (95% confidence interval (CI): 0.96, 1.19) for problematic health literacy and 1.00 (95% CI: 0.87, 1.16) for inadequate health literacy, when using adequate health literacy as the reference value. The association was not modified by socioeconomic or -demographic characteristics, worry or attitude. No association was found between health literacy and colorectal cancer screening uptake. Future research needs to clarify which dimensions of health literacy may predict screening uptake and how it is best measured.

Efficacy and cost-effectiveness of fecal immunochemical test versus colonoscopy in colorectal cancer screening: a systematic review and meta-analysis

BACKGROUND AND AIMS

The fecal immunochemical test (FIT) and colonoscopy are the most commonly used strategies for colorectal cancer (CRC) screening worldwide. We aimed to compare their efficacy and cost-effectiveness in CRC screening in an average-risk population.

METHODS

PubMed, Embase, and National Health Services Economic Evaluation Database were searched. Risk ratio (RR) was used to evaluate the differences in detection rates of colorectal neoplasia between FIT and colonoscopy groups. A random-effects model was used to pool RRs. Incremental cost-effectiveness ratios (ICERs) were calculated to evaluate the cost-effectiveness of FIT versus colonoscopy.

RESULTS

Six randomized controlled trials and 17 cost-effectiveness studies were included. The participation rate in the FIT group was higher than that in the colonoscopy group (41.6% vs 21.9%). In the intention-to-treat analysis, FIT had a detection rate of CRC comparable with colonoscopy (RR, .73; 95% confidence interval, .37-1.42) and lower detection rates of any adenoma and advanced adenoma than 1-time colonoscopy. Most included cost-effectiveness studies showed that annual (13/15) or biennial (5/6) FIT was cost-saving (ICER < $0) or very cost-effective ($0 < ICER ≤ $25000/quality-adjusted life-year) compared with colonoscopy every 10 years.

CONCLUSIONS

FIT may be similar to 1-time colonoscopy in the detection rate of CRC, although it has lower detection rates of any adenoma and advanced adenoma than 1-time colonoscopy. Furthermore, annual or biennial FIT appears to be very cost-effective or cost-saving compared with colonoscopy every 10 years. These findings indicate, at least partly, that FIT is noninferior to colonoscopy in CRC screening in an average-risk population. Our findings should be treated with caution and need to be further confirmed.

Plasma Histone H4 and H4K20 Trimethylation Levels Differ Between Colon Cancer and Precancerous Polyps

BACKGROUND/AIM

No blood-based biomarkers are available to differentiate between colonic tumors and precancerous polyps. Previously we demonstrated levels of trimethylated H4K20 (H4K20me3) to be lower in blood plasma from patients with colon cancer than those from cancer-free individuals. Herein, we added individuals with precancerous polyps for the first time in order to analyze and investigate the usefulness of plasma H4K20me3 and histone H4 to discriminate colon tumors from precancerous polyps.

MATERIALS AND METHODS

The study included a cohort of 185 individuals undergoing colonoscopy. H4K20me3 and histone H4, measured by an enzyme-linked immunosorbent assay-like assay in plasma, were analyzed according to colonoscopy findings.

RESULTS

Levels of H4K20me3 were lower in patients with colon cancer than in individuals with normal colonoscopy and those with precancerous polyps (p=0.02 and p=0.01, respectively). In contrast, highest quantities of histone H4 were measured in those with colon cancer compared to other groups (all p<0.01).

CONCLUSION

Beside H4K20me3, plasma histone H4 is a useful marker to discriminate colonic tumors from precancerous polyps and other conditions.

Consensus statement of the Italian society of colorectal surgery (SICCR): management and treatment of hemorrhoidal disease

Hemorrhoidal disease (HD) is the most common proctological disease in the Western countries. However, its real prevalence is underestimated due to the frequent self-medication.The aim of this consensus statement is to provide evidence-based data to allow an individualized and appropriate management and treatment of HD. The strategy used to search for evidence was based on application of electronic sources such as MEDLINE, PubMed, Cochrane Review Library, CINAHL, and EMBASE.These guidelines are inclusive and not prescriptive.The recommendations were defined and graded based on the current levels of evidence and in accordance with the criteria adopted by American College of Chest Physicians. The recommendations were graded A, B, and C.

Serum S100A6, S100A8, S100A9 and S100A11 proteins in colorectal neoplasia: results of a single centre prospective study

S100 proteins are involved in biological events related to colorectal carcinogenesis. Aim of this prospective study was to assess serum concentration of S100A6, A8, A9 and A11 proteins in patients with colorectal neoplasia. Eighty-four subjects were enrolled: 20 controls (average risk population with normal findings on colonoscopy; 7 men, 13 women, age 23-74, mean 55 ± 14), 20 patients with non-advanced colorectal adenoma (non-AA, 10 men, 10 women, age 41-82, mean 62 ± 11), 22 with advanced colorectal adenoma (AA, 15 men, 7 women, age 49-80, mean 64 ± 8) and 22 with colorectal cancer (CRC, 12 men, 10 women, age 49-86, mean 69 ± 10). Peripheral venous blood was obtained. Serum S100 proteins were investigated by enzyme immunoassay technique. Serum S100A6 was significantly lower in CRC (mean 8530 ± 4743 ng/L), p = .035 compared to controls (mean 11308 ± 2968 ng/L). Serum S100A8 was significantly higher in AA (median 11955 ng/L, IQR 2681-34756 ng/L), p = .009 and in CRC (median 27532 ng/L, IQR 6794-35092 ng/L), p < .001 compared to controls (median 2513 ng/L, IQR 2111-4881 ng/L). Serum S100A9 concentrations did not differ between any tested group and controls, p > .05. Serum concentration of S100A11 was significantly lower in non-AA (mean 3.5 ± 2.4 μg/L), p = .004 and in CRC (mean 3.4 ± 2.4 μg/L), p = .002 compared to controls (mean 5.9 ± 2.5 μg/L). Sensitivity and specificity for S100A8 protein in patients with CRC were 94% and 73%; positive predictive value 68% and negative predictive value 95%. Patients with colorectal neoplasia have significantly lower serum S100A6 and S100A11 levels, significantly higher S100A8 and unaltered serum S100A9 levels.

Cost-effectiveness and budget impact analyses of colorectal cancer screenings in a low- and middle-income country: example from Thailand

Objectives: Colorectal cancer (CRC) screening programs have been reported to be cost-effective in many high-income countries. However, there was no such study in low- and middle-income countries. This study aimed to evaluate cost-effectiveness and budget impact of CRC screening modalities for average-risk persons in Thailand.Methods: A decision tree coupled with a Markov model was used to estimate lifetime costs and health benefits of fecal immunochemical test (FIT) and colonoscopy using a societal perspective. The input parameters were obtained from a CRC screening project at a Thai tertiary care hospital, Thai health care costs and databases, and systematic literature review. Results were reported as incremental cost-effectiveness ratios (ICERs) in 2017 US Dollars (USD) per quality-adjusted life year (QALY) gained. Sensitivity analyses were performed to assess the influence of parameter uncertainty. Finally, budget impact analysis was conducted.Results: At the Thai ceiling threshold of societal willingness-to-pay of 4,706 USD, the screening colonoscopy every 10 years and annual FIT, starting at age 50, was cost-effective, as compared to no screening resulting in 15.09 and 15.00 QALYs with the ICERs of 600.20 and 509.84 USD/QALY gained, respectively. Colonoscopy every 10 years and annual FIT could prevent 17.9% and 5.7% of early stage cancer and 27.8% and 9.2% of late stage cancer per 100,000 screening over lifetime when compared to no screening, respectively. The colonoscopy screening was cost-effective with the ICER of 646.53 USD/QALY gained when compared to FIT. The probabilities of being cost-effective for the colonoscopy and FIT were 75% and 25%, respectively. Budget impact analysis showed the colonoscopy screening required an 8-times higher budget than FIT.Conclusions: Colonoscopy offers the best value for money of CRC screenings in Thailand. Annual FIT is potentially feasible since it requires less resources. Our findings can be used as part of evidence for informing policy decision making.Key points for decision makersThere was a lack of cost-effective study of colorectal cancer screening programs in low- and middle-income countries.This study evaluated lifetime health outcomes and costs, and the cost-effectiveness of colorectal screening options for average-risk persons in Thailand.Colonoscopy screening every 10 years is cost-effective with high probability of being cost-effective as compared with annual fecal immunochemical test.Screening by annual fecal immunochemical test is more feasible in terms of human resource and budgetary burden.Colorectal screening programs provides an opportunity for early diagnosis and treatments to prevent advance colorectal stages and avoid higher consequent costs.This study contributes a new evidence-based knowledge for Thailand and can be used to support policy decision making process.

Long noncoding MAGI2-AS3 promotes colorectal cancer progression through regulating miR-3163/TMEM106B axis

Colorectal cancer (CRC), is mostly derived from normal colon epithelial cells, and has been reported to be one of most common gastrointestinal malignancies globally. An increasing number of researchers have claimed that long noncoding RNAs (lncRNAs) exert significant functions in tumor progression. Nevertheless, the function of MAGI2-AS3 remains uncertain in CRC. The expression of MAGI2-AS3, miR-3163, and transmembrane protein 106B (TMEM106B) messenger RNA was examined by quantitative real-time polymerase chain reaction. Cell apoptosis was measured by caspase-3 activity test. Cell proliferation was tested by cell-counting kit 8 and 5-ethynyl-2'-deoxyuridine assays. Cell migration was detected by transwell assay. Western blot analysis examined the protein expression of TMEM106B. The expression of Ki-67 was evaluated by immunohistochemistry assay. The binding capacity between miR-3163 and MAGI2-AS3 (or TMEM106B) was studied by radioimmunoprecipitation and luciferase reporter assays. The expression of MAGI2-AS3 and TMEM106B was conspicuously upregulated whereas miR-3163 presented lower expression in CRC cells. MAGI2-AS3 deficiency facilitated cell apoptosis but hampered cell proliferation and migration. MAGI2-AS3 combined with miR-3163 and negatively regulated miR-3163 expression. In addition, the administration of sh-MAGI2-AS3 or miR-3163 mimics suppressed CRC cell growth in vivo. Subsequently, miR-3163 targeted TMEM106B and the transfection of sh-MAGI2-AS3 or miR-3163 mimics downregulated TMEM106B expression. Rescue assays verified that TMEM106B overexpression recovered the effects of MAGI2-AS3 inhibition on cell apoptosis, proliferation, and migration in CRC. MAGI2-AS3 drives CRC progression through regulating miR-3163/TMEM106B axis. This supplies innovative insights on the investigation of molecular mechanism in CRC progression.

Expression of septin 2 and association with clinicopathological parameters in colorectal cancer

Septin 2 (SEPT2) is a tumor-related gene belonging to the SEPT family that affects the cellular processes of hepatoma carcinoma cells, glioblastoma cells and mesangial cells and is highly expressed in breast cancer, biliary tract cancer and acute myeloid leukemia. Colorectal cancer (CRC) is the third most common type of malignancy in humans. In the present study, Oncomine database was used to compare the expression pattern of SEPT2 mRNA between CRC and normal tissues. Additionally, protein expression in 90 pairs of CRC and paracancerous tissues was analyzed by western blotting and immunohistochemistry (IHC). The results showed that SEPT2 was highly expressed in CRC tissues at the mRNA and protein levels. SEPT2 expression quantified by IHC was associated with lymph node metastasis, the degree of differentiation and TNM staging. Increased SEPT2 wass associated with reduced overall survival (OS) according to Kaplan-Meier analysis. COX proportional hazard analysis indicated that SEPT2 was an independent factor that influenced the OS of patients with CRC. Therefore, SEPT2 was associated with the occurrence, progression and prognosis of CRC and thus, may be a marker and prognostic indicator of CRC.

Microbiome and colorectal cancer: Roles in carcinogenesis and clinical potential

The gastrointestinal tract harbors most of the microbiota associated with humans. In recent years, there has been a surge of interest in assessing the relationships between the gut microbiota and several gut alterations, including colorectal cancer. Changes in the gut microbiota in patients suffering colorectal cancer suggest a possible role of host-microbe interactions in the origin and development of this malignancy and, at the same time, open the door for novel ways of preventing, diagnosing, or treating this disease. In this review we survey current knowledge on the healthy microbiome of the gut and how it is altered in colorectal cancer and other related disease conditions. In describing past studies we will critically assess technical limitations of different approaches and point to existing challenges in microbiome research. We will have a special focus on host-microbiome interaction mechanisms that may be important to explain how dysbiosis can lead to chronic inflammation and drive processes that influence carcinogenesis and tumor progression in colon cancer. Finally, we will discuss the potential of recent developments of novel microbiota-based therapeutics and diagnostic tools for colorectal cancer.

Tumor-derived exosomes: Potential biomarkers and therapeutic target in the treatment of colorectal cancer

Colorectal cancer (CRC) is the third most common cause of cancer-related death in men and women in many countries. Early detection of CRC helps to prevent the advanced stages of the disease, and may thereby improve the survival of these patients. A noninvasive test with high specificity and sensitivity is required for this. Exosomes are lipid bilayer membrane nanovesicles that are released into most body fluids and especially in the microenvironment of cancer. They carry various proteins, lipids, and nucleic materials such as DNA, RNA, messenger RNA (mRNA), and microRNA (miRNA), and may also alter the function of target cells. In this review, we aimed to describe the biogenesis, composition, function, and the role of tumor-derived exosomes in cancer progression. Moreover, their applications in tumor diagnosis and treatment are described, with a particular focus on CRC.