Fecal Occult Blood Testing

Protocol paper for an implementation science approach to promoting colorectal cancer screening in Federally Qualified Health Center clinics: A stepped-wedge, multilevel intervention trial

Background

Colorectal cancer is the third leading cause of cancer-related deaths in the United States. Despite the Healthy People 2030 goal of 70.5%, colorectal cancer (CRC) screening rates in Federally Qualified Health Centers (FQHCs) are suboptimal at about 40%. The Colorectal Cancer Awareness, Research, Education and Screening-Rural Expansion, Access, and Capacity for Health (CARES-REACH) study seeks to address this disparity and accelerate the adoption and utilization of effective, evidence-based CRC screening practices. This paper describes the CARES-REACH study design and implementation methods.

Methods

Informed by a community-based participatory research (CBPR) framework and enriched by implementation science approaches, CARES-REACH features a stepped wedge design with extension for maintenance to support an implementation strategy focused on multiple levels: organizational, provider, and patient levels that entail processes to boost initial and repeat screening among average risk and age-eligible adults. This multilevel study entails the implementation of a core set of evidence-based interventions (EBIs) that include low literacy patient education (English, Spanish, and Haitian Creole language); provider education, system-wide electronic medical record (EMR) tools including provider prompts and patient reminders, FIT (fecal immunochemical test) kit distribution, plus an organization-wide cancer control champion who motivates providers, coaches and navigates patients, and monitors system-wide CRC screening activities.

Trial registration

NCT04464668.

'Simple and easy:' providers' and latinos' perceptions of the fecal immunochemical test (FIT) for colorectal cancer screening

Objective: Colorectal cancer (CRC) screening efforts have effectively reduced CRC morbidity and mortality, yet screening remains relatively low among Latinos. The study's purpose was to document the awareness/knowledge of Fecal Immunochemical Test (FIT) among Latinos, gain better understanding of patient and health care provider perceptions about FIT, and explore the feasibility of adoption/uptake.Design/Methods: The study was guided by qualitative, ethnography design and methods. Eight focus groups (FG) with patients who self-identified as Hispanic/Latino between 50-75 years of age and key informant interviews with providers (N = 10) were conducted followed by a brief demographic questionnaire.Results: Awareness levels varied based on prior screening experiences among patients and providers. Both patients and providers believed the FIT is simple and easy to use; although, a minority of patients expressed doubts about the efficacy of the FIT when compared to colonoscopy.Conclusions: Despite the increasing acceptance of the FIT among the health care community, a significant lag time still exists among our study's populations. Study findings speak to novelty of the FIT test among underserved populations and the health disparity gap between health innovations/discoveries. Increased awareness and education efforts about the efficacy coupled with information about its accessibility, ease, and user instructions may increase the adoption of FIT.

A culturally and linguistically salient pilot intervention to promote colorectal cancer screening among Latinos receiving care in a Federally Qualified Health Center

Despite established benefits, colorectal cancer (CRC) screening is underutilized among Latinos/Hispanics. We conducted a pilot 2-arm randomized controlled trial evaluating efficacy of two intervention conditions on CRC screening uptake among Latinos receiving care in community clinics. Participants (N = 76) were aged 50-75, most were foreign-born, preferred to receive their health information in Spanish, and not up-to-date with CRC screening. Participants were randomized to either a culturally linguistically targeted Spanish-language fotonovela booklet and DVD intervention plus fecal immunochemical test [FIT] (the LCARES, Latinos Colorectal Cancer Awareness, Research, Education and Screening intervention group); or a non-targeted intervention that included a standard Spanish-language booklet plus FIT (comparison group). Measures assessed socio-demographic variables, health literacy, CRC screening behavior, awareness and beliefs. Overall, FIT uptake was 87%, exceeding the National Colorectal Cancer Roundtable's goal of 80% by 2018. The LCARES intervention group had higher FIT uptake than did the comparison group (90% versus 83%), albeit not statistically significant (P = 0.379). The LCARES intervention group was associated with greater increases in CRC awareness (P = 0.046) and susceptibility (P = 0.013). In contrast, cancer worry increased more in the comparison group (P = 0.045). Providing educational materials and a FIT kit to Spanish-language preferring Latinos receiving care in community clinics is a promising strategy to bolster CRC screening uptake to meet national targets.

Reduction of faecal immunochemical test false-positive results using a signature based on faecal bacterial markers

BACKGROUND

Colorectal cancer is the second commonest cause of cancer mortality. Some countries are implementing colorectal cancer screening to detect lesions at an early stage using non-invasive tools like the faecal immunochemical test. Despite affordability, this test shows a low sensitivity for precancerous lesions and a low positive predictive value for colorectal cancer, resulting in a high false-positive rate.

AIM

To develop a new, non-invasive colorectal cancer screening tool based on bacterial faecal biomarkers, which in combination with the faecal immunochemical test, could allow a reduction in the false-positive rate. This tool is called risk assessment of intestinal disease for colorectal cancer (RAID-CRC).

METHODS

We performed both the faecal immunochemical test and the bacterial markers analysis (RAID-CRC test) in stool samples from individuals with normal colonoscopy (167), non-advanced adenomas (88), advanced adenomas (30) and colorectal cancer (48). All the participants showed colorectal cancer-associated symptoms.

RESULTS

Performance of the faecal immunochemical test for advanced neoplasia (ie advanced adenoma and colorectal cancer) was determined by using the cut-off value established in Catalonia (20 µg haemoglobin/g of faeces) for a population-based screening approach. Sensitivity and specificity values of 83% and 80%, respectively, and positive and negative predictive values of 56% and 94%, respectively, were obtained. When both the immunological and the biological analysis were combined, the corresponding values were 80% and 90% for sensitivity and specificity, respectively, and 70% and 94% for positive and negative predictive values, respectively, resulting in a 50% reduction of the false-positive rate.

CONCLUSIONS

RAID-CRC test allows a substantial reduction in the faecal immunochemical test false-positive results (50%) in a symptomatic population. Further validation is indicated in a colorectal cancer-screening scenario.

Combined Diagnostic Efficacy of Neutrophil-to-Lymphocyte Ratio (NLR), Platelet-to-Lymphocyte Ratio (PLR), and Mean Platelet Volume (MPV) as Biomarkers of Systemic Inflammation in the Diagnosis of Colorectal Cancer

Background

Systemic inflammation in colorectal cancer (CRC) may be reflected by neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and mean platelet volume (MPV). This study was designed to investigate the efficiency of preoperative NLR, PLR, and MVP as a tool for the assessment of tumor characteristics in newly diagnosed patients with CRC.

Patients and Methods

For 300 patients and 300 healthy volunteers, complete blood counts with automated differential counts were performed. The NLR was calculated by dividing the absolute neutrophil count by the absolute lymphocyte count; PLR was calculated by dividing the absolute platelet count by the absolute lymphocyte count. The diagnostic performance of NLR, PLR, and MVP was estimated by ROC curve.

Results

ROC curve analysis showed high diagnostic efficacy of NLR and PLR in CRC patients with cut-off values of 2.15 (AUC = 0.790, 95% CI 0.736-0.884, Se = 74.1%, and Sp = 73%) and 123 (AUC = 0.846, 95% CI 0.801-0.891, Se = 73.5%, and Sp = 80%) compared to healthy controls, respectively. The diagnostic efficacy of three combined markers was superior compared with individual markers (AUC = 0.904, 95% CI 0.812-0.989, Se = 96%, and Sp = 70%).

Conclusion

NRL, PLR, and MPV may be useful markers in diagnostic and early recognition of different stages of CRC; additionally combined all together have stronger diagnostic efficacy.

Mechanisms Linking Colorectal Cancer to the Consumption of (Processed) Red Meat: A Review

Colorectal cancer (CRC) is the third most commonly diagnosed cancer in the world. The vast majority of CRC cases have been linked to environmental causes rather than to heritable genetic changes. Over the last decades, epidemiological evidence linking the consumption of red and, more convincingly, of processed red meat to CRC has accumulated. In parallel, hypotheses on carcinogenic mechanisms underlying an association between CRC and the intake of red and processed red meat have been proposed and investigated in biological studies. The hypotheses that have received most attention until now include (1) the presence of polycyclic aromatic hydrocarbons and heterocyclic aromatic amines, two groups of compounds recognized as carcinogenic, (2) the enhancing effect of (nitrosyl)heme on the formation of carcinogenic N-nitroso compounds and lipid peroxidation. However, none of these hypotheses completely explains the link between red and processed red meat intake and the CRC risk. Consequently, scientists have proposed additional mechanisms or refined their hypotheses. This review first briefly summarizes the development of CRC followed by an in-depth overview and critical discussion of the different potential carcinogenic mechanisms underlying the increased CRC risk associated with the consumption of red and processed red meat.

miRNA profiling of circulating EpCAM(+) extracellular vesicles: promising biomarkers of colorectal cancer

Cancer cells secrete small membranous extracellular vesicles (EVs) into their microenvironment and circulation. These contain biomolecules, including proteins and microRNAs (miRNAs). Both circulating EVs and miRNAs have received much attention as biomarker candidates for non-invasive diagnostics. Here we describe a sensitive analytical method for isolation and subsequent miRNA profiling of epithelial-derived EVs from blood samples of patients with colorectal cancer (CRC). The epithelial-derived EVs were isolated by immunoaffinity-capture using the epithelial cell adhesion molecule (EpCAM) as marker. This approach mitigates some of the specificity issues observed in earlier studies of circulating miRNAs, in particular the negative influence of miRNAs released by erythrocytes, platelets and non-epithelial cells. By applying this method to 2 small-scale patient cohorts, we showed that blood plasma isolated from CRC patients prior to surgery contained elevated levels of 13 EpCAM⁺-EV miRNAs compared with healthy individuals. Upon surgical tumour removal, the plasma levels of 8 of these were reduced (miR-16-5p, miR-23a-3p, miR-23b-3p, miR-27a-3p, miR-27b-3p, miR-30b-5p, miR-30c-5p and miR-222-3p). These findings indicate that the miRNAs are of tumour origin and may have potential as non-invasive biomarkers for detection of CRC. This work describes a non-invasive blood-based method for sensitive detection of cancer with potential for clinical use in relation to diagnosis and screening. We used the method to study CRC; however, it is not restricted to this disease. It may in principle be used to study any cancer that release epithelial-derived EVs into circulation.

Patients' perceptions of colorectal cancer screening tests and preparatory education in federally qualified health centers

This study explored federally qualified health center (FQHC) patients' perceptions about colorectal cancer screening (CRCS) tests, including immunochemical fecal occult blood tests (iFOBT), as well as preferences for receiving in-clinic education about CRCS. Eight mixed gender focus groups were conducted with 53 patients. Findings centered on three thematic factors: (1) motivators and impediments to CRCS, (2) test-specific preferences and receptivity to iFOBTs, and (3) preferences for entertaining and engaging plain language materials. Results informed the development of educational priming materials to increase CRCS using iFOBT in FQHCs.

Public stated preferences and predicted uptake for genome-based colorectal cancer screening

Background

Emerging developments in nanomedicine allow the development of genome-based technologies for non-invasive and individualised screening for diseases such as colorectal cancer. The main objective of this study was to measure user preferences for colorectal cancer screening using a nanopill.

Methods

A discrete choice experiment was used to estimate the preferences for five competing diagnostic techniques including the nanopill and iFOBT. Alternative screening scenarios were described using five attributes namely: preparation involved, sensitivity, specificity, complication rate and testing frequency. Fourteen random and two fixed choice tasks, each consisting of three alternatives, were offered to 2225 individuals. Data were analysed using the McFadden conditional logit model.

Results

Thirteen hundred and fifty-six respondents completed the questionnaire. The most important attributes (and preferred levels) were the screening technique (nanopill), sensitivity (100%) and preparation (no preparation). Stated screening uptake for the nanopill was 79%, compared to 76% for iFOBT. In the case of screening with the nanopill, the percentage of people preferring not to be screened would be reduced from 19.2% (iFOBT) to 16.7%.

Conclusions

Although the expected benefits of nanotechnology based colorectal cancer screening are improved screening uptake, assuming more accurate test results and less preparation involved, the relative preference of the nanopill is only slightly higher than the iFOBT. Estimating user preferences during the development of diagnostic technologies could be used to identify relative performance, including perceived benefits and harms compared to competitors allowing for significant changes to be made throughout the process of development.

Detection of serological biomarkers by proximity extension assay for detection of colorectal neoplasias in symptomatic individuals

Background

Although the potential of biomarkers to aid in early detection of colorectal cancer (CRC) is recognized and numerous biomarker candidates have been reported in the literature, to date only few molecular markers have been approved for daily clinical use.

Methods

In order to improve the translation of biomarkers from the bench to clinical practice we initiated a biomarker study focusing on a novel technique, the proximity extension assay, with multiplexing capability and the possible additive effect obtained from biomarker panels. We performed a screening of 74 different biomarkers in plasma derived from a case–control sample set consisting of symptomatic individuals representing CRC patients, patients with adenoma, patients with non-neoplastic large bowel diseases and healthy individuals.

Results

After statistical evaluation we found 12 significant indicators of CRC and the receiver operating characteristic (ROC) curve of Carcinoembryonic antigen (CEA), Transferrin Receptor-1 (TFRC), Macrophage migration inhibitory factor (MIF), Osteopontin (OPN/SPP1) and cancer antigen 242 (CA242) showed additive effect. This biomarker panel identified CRC patients with a sensitivity of 56% at 90% specificity and thus the performance is sufficiently high to further investigate this combination of five proteins as serological biomarkers for detection of CRC. Furthermore, when applying the indicators to identify early-stage CRC a combination of CEA, TFRC and CA242 resulted in a ROC curve with an area under the curve of 0.861.

Conclusions

Five plasma protein biomarkers were found to be potential CRC discriminators and three of these were additionally found to be discriminators of early-stage CRC. These explorative data in symptomatic individuals demonstrates the feasibility of the multiplex proximity extension assay for screening of potential serological protein biomarkers and warrants independent analyses in a larger sample cohort, including asymptomatic individuals, to further validate the performances of our CRC biomarker panel.

Computer-aided colorectal tumor classification in NBI endoscopy using local features

An early detection of colorectal cancer through colorectal endoscopy is important and widely used in hospitals as a standard medical procedure. During colonoscopy, the lesions of colorectal tumors on the colon surface are visually inspected by a Narrow Band Imaging (NBI) zoom-videoendoscope. By using the visual appearance of colorectal tumors in endoscopic images, histological diagnosis is presumed based on classification schemes for NBI magnification findings. In this paper, we report on the performance of a recognition system for classifying NBI images of colorectal tumors into three types (A, B, and C3) based on the NBI magnification findings. To deal with the problem of computer-aided classification of NBI images, we explore a local feature-based recognition method, bag-of-visual-words (BoW), and provide extensive experiments on a variety of technical aspects. The proposed prototype system, used in the experiments, consists of a bag-of-visual-words representation of local features followed by Support Vector Machine (SVM) classifiers. A number of local features are extracted by using sampling schemes such as Difference-of-Gaussians and grid sampling. In addition, in this paper we propose a new combination of local features and sampling schemes. Extensive experiments with varying the parameters for each component are carried out, for the performance of the system is usually affected by those parameters, e.g. the sampling strategy for the local features, the representation of the local feature histograms, the kernel types of the SVM classifiers, the number of classes to be considered, etc. The recognition results are compared in terms of recognition rates, precision/recall, and F-measure for different numbers of visual words. The proposed system achieves a recognition rate of 96% for 10-fold cross validation on a real dataset of 908 NBI images collected during actual colonoscopy, and 93% for a separate test dataset.

Screening for colorectal cancer: possible improvements by risk assessment evaluation?

Emerging results indicate that screening improves survival of patients with colorectal cancer. Therefore, screening programs are already implemented or are being considered for implementation in Asia, Europe and North America. At present, a great variety of screening methods are available including colono- and sigmoidoscopy, CT- and MR-colonography, capsule endoscopy, DNA and occult blood in feces, and so on. The pros and cons of the various tests, including economic issues, are debated. Although a plethora of evaluated and validated tests even with high specificities and reasonable sensitivities are available, an international consensus on screening procedures is still not established. The rather limited compliance in present screening procedures is a significant drawback. Furthermore, some of the procedures are costly and, therefore, selection methods for these procedures are needed. Current research into improvements of screening for colorectal cancer includes blood-based biological markers, such as proteins, DNA and RNA in combination with various demographically and clinically parameters into a "risk assessment evaluation" (RAE) test. It is assumed that such a test may lead to higher acceptance among the screening populations, and thereby improve the compliances. Furthermore, the involvement of the media, including social media, may add even more individuals to the screening programs. Implementation of validated RAE and progressively improved screening methods may reform the cost/benefit of screening procedures for colorectal cancer. Therefore, results of present research, validating RAE tests, are awaited with interest.

Does participation to screening unintentionally influence lifestyle behaviour and thus lifestyle-related morbidity?

Cancer is a leading cause of death worldwide and the burden could be reduced by evidence-based strategies for the primary prevention of cancer, the early detection of malignancies and more adequate treatment of cancer patients. Previous research has shown that lifestyle factors are associated with common cancers and that several cancer screening programmes are cost-effective in reducing cancer-specific mortality. But, some recent studies reported that participants of screening programs might unintentionally change their lifestyle. Cancer screening might be a teachable moment or, on the other hand, have a false health certificate effect. Despite that the evidence is scarce, cancer screening might have opportunities for lifestyle improvements, although a possible health certificate effect still remains. Integrated approaches to combine primary and secondary prevention have the potential to optimise the efforts to improve cancer prevention and survival. More research is warranted to investigate evidence-based approaches.