Decision-making in fecal occult blood test compliance: A quali-quantitative study investigating motivational processes

A 5-Hydroxymethylcytosine-Based Noninvasive Model for Early Detection of Colorectal Carcinomas and Advanced Adenomas: The METHOD-2 Study

PURPOSE

Detection of colorectal carcinomas at a time when there are more treatment options is associated with better outcomes. This prospective case-control study assessed the 5-hydroxymethylcytosine (5hmC) biomarkers in circulating cell-free DNA (cfDNA) for early detection of colorectal carcinoma and advanced adenomas (AA).

EXPERIMENTAL DESIGN

Plasma cfDNA samples from 2,576 study participants from the multicenter METHOD-2 study (NCT03676075) were collected, comprising patients with newly diagnosed colorectal carcinoma (n = 1,074), AA (n = 356), other solid tumors (n = 80), and non-colorectal carcinoma/AA controls (n = 1,066), followed by genome-wide 5hmC profiling using the 5hmC-Seal technique and the next-generation sequencing. A weighted diagnostic model for colorectal carcinoma (stage I-III) and AA was developed using the elastic net regularization in a discovery set and validated in independent samples.

RESULTS

Distribution of 5hmC in cfDNA reflected gene regulatory relevance and tissue of origin. Besides being confirmed in internal validation, a 96-gene model achieved an area under the curve (AUC) of 90.7% for distinguishing stage I-III colorectal carcinoma from controls in 321 samples from multiple centers for external validation, regardless of primary location or mutation status. This model also showed cancer-type specificity as well as high capacity for distinguishing AA from controls with an AUC of 78.6%. Functionally, differential 5hmC features associated with colorectal carcinoma and AA demonstrated relevance to colorectal carcinoma biology, including pathways such as calcium and MAPK signaling.

CONCLUSIONS

Genome-wide mapping of 5hmC in cfDNA shows promise as a highly sensitive and specific noninvasive blood test to be integrated into screening programs for improving early detection of colorectal carcinoma and high-risk AA.

Facing the Emotional Barriers to Colorectal Cancer Screening. The Roles of Reappraisal and Situation Selection

BACKGROUND

Disgust, embarrassment, and fear can hinder the attendance of colorectal cancer (CRC) screening. However, individuals can respond to these emotions differently. The present study tested whether reappraising a negative stimulus versus avoiding a negative stimulus is associated with age; whether these two emotion regulation strategies (reappraisal and situation selection) moderate the effects of disgust, embarrassment and fear on CRC screening intention; and the efficacy of a message based on participants' preferred emotion regulation strategy.

METHODS

We recruited 483 Italian participants (aged 40-84 years) through snowball sampling. Participants were randomly assigned to one of four conditions differing for a message promoting CRC screening with an affective lever, a cognitive lever, both levers or none. Key variables included emotion regulation strategies, emotional barriers and intention to get screened.

RESULTS

The preference for reappraisal over situation selection increased with age. Reappraisal neutralized the effect of disgust on CRC screening intention. The combined message with both affective and cognitive levers increased CRC screening intention (b = 0.27, β = 0.11, SE = 0.13 p = .049), whereas reading the message based only on the affective (b = 0.16, β = 0.06, SE = 0.14 p = .258) or the cognitive (b = 0.22, β = 0.09, SE = 0.14 p = .107) lever was not effective.

CONCLUSIONS

Communication campaigns should support the activation of a reappraisal strategy of emotion control, and messages promoting CRC screening should highlight both the instrumental (i.e., early detection) and affective (i.e., peace of mind) benefits of attendance.

Machine learning identifies cell-free DNA 5-hydroxymethylation biomarkers that detect occult colorectal cancer in PLCO Screening Trial subjects

Background

Colorectal cancer (CRC) is a leading cause of cancer-related mortality, and CRC detection through screening improves survival rates. A promising avenue to improve patient screening compliance is the development of minimally-invasive liquid biopsy assays that target CRC biomarkers on circulating cell-free DNA (cfDNA) in peripheral plasma. In this report, we identify cfDNA biomarker candidate genes bearing the epigenetic mark 5-hydroxymethylcytosine (5hmC) that diagnose occult CRC up to 36 months prior to clinical diagnosis using the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial samples.

Methods

Archived PLCO Trial plasma samples containing cfDNA were obtained from the National Cancer Institute (NCI) biorepositories. Study subjects included those who were diagnosed with CRC within 36 months of blood collection (i.e., case, n = 201) and those who were not diagnosed with any cancer during an average of 16.3 years of follow-up (i.e., controls, n = 402). Following the extraction of 3 - 8 ng cfDNA from less than 300 microliters plasma, we employed the sensitive 5hmC-Seal chemical labeling approach, followed by next-generation sequencing (NGS). We then conducted association studies and machine-learning modeling to analyze the genome-wide 5hmC profiles within training and validation groups that were randomly selected at a 2:1 ratio.

Results

Despite the technical challenges associated with the PLCO samples (e.g., limited plasma volumes, low cfDNA amounts, and long archival times), robust genome-wide 5hmC profiles were successfully obtained from these samples. Association analyses using the Cox proportional hazards models suggested several epigenetic pathways relevant to CRC development distinguishing cases from controls. A weighted Cox model, comprised of 32-associated gene bodies, showed predictive detection value for CRC as early as 24-36 months prior to overt tumor presentation, and a trend for increased predictive power was observed for blood samples collected closer to CRC diagnosis. Notably, the 5hmC-based predictive model showed comparable performance regardless of sex and self-reported race/ethnicity, and significantly outperformed risk factors such as age and obesity according to BMI (body mass index). Additionally, further improvement of predictive performance was achieved by combining the 5hmC-based model and risk factors for CRC.

Conclusions

An assay of 5hmC epigenetic signals on cfDNA revealed candidate biomarkers with the potential to predict CRC occurrence despite the absence of clinical symptoms or the availability of effective predictors. Developing a minimally-invasive clinical assay that detects 5hmC-modified biomarkers holds promise for improving early CRC detection and ultimately patient survival through higher compliance screening and earlier intervention. Future investigation to expand this strategy to prospectively collected samples is warranted.

Exploring non-participation in colorectal cancer screening: A systematic review of qualitative studies

INTRODUCTION

Worldwide, colorectal cancer is a major public health issue. Despite the existence of screening programmes in many countries, global uptake remains low. This meta-ethnography aimed to analyse qualitative literature to explore attitudes towards colorectal cancer screening and reasons for non-participation in eligible people that do not participate when invited.

METHODS

Systematic searches were conducted in five databases in May 2021. Critical appraisal of included studies was performed using the CASP checklist for qualitative studies.

FINDINGS

Thirteen studies were included. Three main themes and eight sub-themes were developed across studies: (1) Differences in motivation, with non-participants expressing a lack of knowledge and varying levels of intention to participate but not feeling screening was personally necessary; (2) Active aversion to screening expressed by fear, discomfort, disgust or not wanting to know; and (3) Contextual barriers of the healthcare system such as practical constraints or poor relationships with healthcare professionals.

CONCLUSION

Findings suggest multiple pathways to non-participation including ambivalence, aversion to the process and consequences of screening or lack of support. Persuasive messages and prompts to action to target ambivalence, reassurance regarding the screening procedures to target negative reactions, and increased support from healthcare professionals may be beneficial in increasing screening uptake.

How do women comply with cancer screenings? A study in four regions of France

BACKGROUND

This article looks at the behaviour of women facing different cancer screening options available to them from the age of 50 onward. The study was conducted in 2019 in four departments of the French territory with the objective of identifying the factors that influence acceptance of a population-based screening proposal.

METHODS

A questionnaire was sent to women who had received three invitations to organised screenings (OS) for both breast and colorectal cancer. The categories of participants in both OS were designed from data from the regional cancer screening coordination centres in each department. Participation in opportunistic cervical cancer screening was evaluated as self-reported data.

RESULTS

4,634 questionnaires were returned out of the 17,194 sent, giving a global return rate of 27%. The highest rate of return (73.5%) was obtained from women who had participated at least once in both breast and colorectal cancer OS. An intermediate rate was obtained from women participating in breast cancer OS only (18.7%). Poor levels of return came from women who had participated in colorectal cancer OS only (3.6%) and from non-participants (4.1%). Our results suggest that women with lower educational levels tend to be the most regular attendants at OS (50.3%), compared to highly educated women (39.7%). 11.8% of women were overdue in their opportunistic cervical cancer screening. This percentage rose to 35.4% in the category of non-participants. In addition, women's comments provide a better understanding of the reasons for irregular attendance and non-participation.

CONCLUSION

Overall, similar behaviours towards screening were observed in the four departments. Our analysis suggests that participation in one cancer OS increases the likelihood of participating in others. This adhesion could be an interesting lever for raising women's awareness of other cancer screenings.

The role of disgust as an emotional barrier to colorectal cancer screening participation: a systematic review and meta-analysis

OBJECTIVE

Worldwide colorectal cancer (CRC) screening rates are suboptimal. This systematic review and meta-analysis examine the role of disgust in CRC screening avoidance.

DESIGN

A systematic literature search was conducted. In all, 46 studies were included in the review. Among these, 16 studies were compared with a meta-analytical approach in order to 1) estimate the effect size of state disgust on screening intention and attendance; 2) examine whether methodological characteristics moderate the effect of state disgust on screening behaviour; 3) estimate the effect sizes of trait disgust and type of exam kit on state disgust.

RESULTS

In the reviewed studies, state disgust was often associated with CRC screening and especially with CRC screening avoidance. The meta-analysis confirmed low-to-moderate negative effects of state disgust on screening intention and attendance. Population sampling strategy was the only significant moderator of the effect of state disgust on screening attendance, i.e. studies that used convenience (versus random/representative) samples found a significantly lower effect size. Trait disgust and type of exam kit exerted a large and a moderate-to-large positive effect, respectively, on state disgust.

CONCLUSIONS

Disgust can boost CRC screening avoidance. Further studies and interventions must be designed to help patients in overcoming this emotional barrier.

Factors affecting patient adherence to publicly funded colorectal cancer screening programmes: a systematic review

OBJECTIVES

Colorectal cancer (CRC) is the third most common cancer. Many countries in Europe have already implemented systematic screening programmes as per the recommendations by the European Union. The impact of screening is highly dependent on participation rates. The aim of the study was to identify barriers, facilitators and modifiers to participation in systematised, stool sample-based, publicly financed CRC screening programmes.

STUDY DESIGN

Systematic review.

METHODS

A systematic search in PubMed, Embase, MEDLINE, CINAHL, Cochrane CENTRAL, Google Scholar and PsycINFO was undertaken. We included both qualitative and quantitative studies reporting on barriers and facilitators (excluding sociodemographic variables) to participation in stool sample-based CRC screening. Barriers and facilitators to participation were summarised and analysed.

RESULTS

The inclusion criteria were met in 21 studies. Reported barriers and facilitators were categorised into the following seven themes (examples): psychology (fear of cancer), religion (believing cancer is the will of God), logistics (not knowing how to conduct the test), health-related factors (mental health), knowledge and awareness (lack of knowledge about the test), role of the general practitioner (being supported in taking the test by the general practitioner), and environmental factors (knowing someone who has participated in a screening programme). Six studies reported that non-participation was not due to a negative attitude towards screening for CRC.

CONCLUSION

Many barriers to screening were found. It is important to work with peoples' fear of screening. Moreover, this review suggests that it might be possible to increase participation rates, if the population-wide awareness and knowledge of potential health benefits of CRC screening are increased and proper logistical support is provided.

Understanding barriers and facilitators to participation in colorectal cancer screening: A French qualitative study

Based on the theory of social representations, this study aims to identify the main determinants to participation in colorectal cancer screening. Six focus groups (N = 29 participants belonging to the general population) were conducted, followed by a theoretical thematic analysis. Screening obstacles are a lack of test's accessibility, a low preoccupation for prevention and the negative image of colorectal cancer. Conversely, screening facilitators are the ease of the new test, being encouraged to get screened and appointment reminder. This study advances understanding of adherence to screening by addressing the beliefs and knowledge surrounding it.

Gel-Based Proteomics of Clinical Samples Identifies Potential Serological Biomarkers for Early Detection of Colorectal Cancer

The burden of colorectal cancer (CRC) is considerable-approximately 1.8 million people are diagnosed each year with CRC and of these about half will succumb to the disease. In the case of CRC, there is strong evidence that an early diagnosis leads to a better prognosis, with metastatic CRC having a 5-year survival that is only slightly greater than 10% compared with up to 90% for stage I CRC. Clearly, biomarkers for the early detection of CRC would have a major clinical impact. We implemented a coherent gel-based proteomics biomarker discovery platform for the identification of clinically useful biomarkers for the early detection of CRC. Potential protein biomarkers were identified by a 2D gel-based analysis of a cohort composed of 128 CRC and site-matched normal tissue biopsies. Potential biomarkers were prioritized and assays to quantitatively measure plasma expression of the candidate biomarkers were developed. Those biomarkers that fulfilled the preset criteria for technical validity were validated in a case-control set of plasma samples, including 70 patients with CRC, adenomas, or non-cancer diseases and healthy individuals in each group. We identified 63 consistently upregulated polypeptides (factor of four-fold or more) in our proteomics analysis. We selected 10 out of these 63 upregulated polypeptides, and established assays to measure the concentration of each one of the ten biomarkers in plasma samples. Biomarker levels were analyzed in plasma samples from healthy individuals, individuals with adenomas, CRC patients, and patients with non-cancer diseases and we identified one protein, tropomyosin 3 (Tpm3) that could discriminate CRC at a significant level (p = 0.0146). Our results suggest that at least one of the identified proteins, Tpm3, could be used as a biomarker in the early detection of CRC, and further studies should provide unequivocal evidence for the real-life clinical validity and usefulness of Tpm3.

[Representations of colorectal cancer screening: the GPs point of view]

OBJECTIVES

Various studies have shown that general practitioners (GPs) have a strong influence on adherence to organized screening for colorectal cancer. Faced with very low screening rates (29.8%), this study aims to apprehend the context of screening, the representations of GPs and the context of the arrival of new screening test in how to consider medical practice.

METHODS

On the basis of a qualitative methodology, semi-structured interviews were conducted with 17 general practitioners in 2014-2015. A thematic content analysis was then performed.

RESULTS

The doctors interviewed said that they discussed colorectal cancer screening quickly at the end of the consultation, along with other screening tests (mammography), due to lack of time and management of several reasons for consultation. GPs had very little information about the new test, so they had no specific expectations for the new test. The analysis revealed an inconsistency between the role that GPs feel they should play with patients in prevention and screening and the reality of their practice that leaves them little time to devote to it.

CONCLUSIONS

A lack of information regarding the arrival of the new test and the difficulties associated with the organization of care has an impact on the representations of screening management. Setting up a consultation dedicated to prevention could be a prospect of improvement.