Knowledge and attitudes of primary healthcare patients regarding population-based screening for colorectal cancer

Biochemical assessment of the neurotoxicity of gold nanoparticles functionalized with colorectal cancer-targeting peptides in a rat model

The application of gold nanoparticle-peptide conjugates as theranostic agents for colorectal cancer shows much promise. This study aimed at determining the neurotoxic impact of 14 nm gold nanoparticles (AuNPs) functionalized with colorectal cancer-targeting peptides (namely p.C, p.L or p.14) in a rat model. Brain tissue samples, obtained from Wistar rats that received a single injection of citrate-capped AuNPs, polyethylene glycol-coated (PEG) AuNPs, p.C-PEG-AuNPs, p.L-PEG-AuNPs or p.14-PEG-AuNPs, and sacrificed after 2- and 12-weeks, respectively, were analysed. Inflammation marker (tumour necrosis factor-α, interleukin-6, interleukin-1β), oxidative stress (superoxide dismutase, catalase, glutathione peroxidase) and apoptotic biomarker (cytochrome c, caspase-3) levels were measured. Gold nanoparticle-treated groups sacrificed after 2-weeks did not exhibit any significant inflammatory, oxidative stress or apoptotic effects in brain tissue compared to the untreated control group. In brain tissue from rats that were exposed to citrate-capped AuNPs for 12-weeks, tumour necrosis factor-α and interleukin-6 levels were significantly increased compared to the untreated control. Exposure to PEG-AuNP, p.C-PEG-AuNP, p.L-PEG-AuNP and p.14-PEG-AuNP did not elicit significant toxic effects compared to the control after 12-weeks, as evidenced by the absence of inflammatory, oxidative stress and apoptotic effects in brain tissue. We thus report on the safety of PEG-coated AuNP-peptide conjugates for potential application in the diagnosis of colorectal cancer; however, exposure to citrate-capped AuNPs could induce delayed neuro-inflammation, and as such, warrants further investigation.

A Multilevel Approach to Understand the Context and Potential Solutions for Low Colorectal Cancer (CRC) Screening Rates in Rural Appalachia Clinics

PURPOSE

To explore system/staff- and patient-level opportunities to improve colorectal cancer (CRC) screening within an 11-clinic Federally Qualified Health Center (FQHC) in rural Appalachia with CRC screening rates around 22%-30%.

METHODS

Using a convergent parallel mixed-methods design, staff (n = 26) and patients (n = 60, age 50-75, 67% female, 83% <college, 47% Medicare, 23% Medicaid) were interviewed about CRC-related screening practices. Staff and patient interviews were guided by the Consolidated Framework for Implementation Research and Health Belief Model, respectively, and analyzed using a hybrid inductive-deductive approach.

RESULTS

Among staff, inner setting factors that could promote CRC screening included high workplace satisfaction, experiences tracking other cancer screenings, and a highly active Performance Improvement Committee. Inner setting hindering factors included electronic medical record inefficiencies and requiring patients to physically return fecal tests to the clinic. Outer setting CRC screening promoting factors included increased Medicaid access, support from outside organizations, and reporting requirements to external regulators, while hindering factors included poor social determinants of health, inadequate colonoscopy access, and lack of patient compliance. Among patients, perceived screening benefits were rated relatively higher than barriers. Top barriers included cost, no symptoms, fear, and transportation. Patients reported high likelihood of getting a stool-based test and colonoscopy if recommended, yet self-efficacy to prevent CRC was considerably lower.

CONCLUSIONS

Contextualized perceptions of barriers and practical opportunities to improve CRC screening rates were identified among staff and patients. To optimize multilevel CRC screening interventions in rural Appalachia clinics, future quality improvement, research, and policy efforts are needed to address identified challenges.

Opportunistic detection of Fusobacterium nucleatum as a marker for the early gut microbial dysbiosis

Background

The essential roles of gut microbiome have been emphasized in modulating human health and disease. Fusobacterium nucleatum (F. nucleatum), an obligate Gram-negative microorganism residing in oral cavity, gastrointestinal tract and elsewhere, has been recently considered as a potential oncobacterium associated with human cancers. However, the consequence of its enrichment was not extensively explored in terms of microbial homeostasis and stability at the early stage of disease development.

Result

Our analysis on longitudinal metagenomic data generated by the Integrative Human Microbiome Project (iHMP) showed that F. nucleatum was frequently found in inflammatory bowel diseases (IBD) subjects with reduced microbial diversity. Using non-parametric logarithmic linear discriminant analysis (LDA) effect size (LEfSe) algorithm, 12 IBD- and 14 non-IBD-specific bacterial species were identified in the fecal metagenome and the IBD-specific ones were over-represented in the F. nucleatum-experienced subjects during long-term surveillance. In addition, F. nucleatum experience severely abrogated intra-personal stability of microbiome in IBD patients and induced highly variable gut microbiome between subjects. From the longitudinal comparison between microbial distributions prior and posterior to F. nucleatum detection, 41 species could be proposed as indicative “classifiers” for dysbiotic gut state. By multiple logistic regression models established on these classifiers, the high probability of experiencing F. nucleatum was significantly correlated with decreased alpha-diversity and increased number of biomarker species for IBD and colorectal cancer (CRC). Finally, microbial clustering confirmed that biomarker species for IBD and non-IBD conditions as well as CRC signature markers were well distinguishable and could be utilized for explaining gut symbiosis and dysbiosis.

Conclusion

F. nucleatum opportunistically appeared under early dysbiotic condition in gut, and discriminative classifier species associated with F. nucleatum were successfully applied to predict microbial alterations in both IBD and non-IBD conditions. Our prediction model and microbial classifier biomarkers for estimating gut dysbiosis should provide a novel aspect of microbial homeostasis/dynamics and useful information on non-invasive biomarker screening.

Circulating Cell-Free DNA and Colorectal Cancer: A Systematic Review

There is a strong demand for the identification of new biomarkers in colorectal cancer (CRC) diagnosis. Among all liquid biopsy analysts, cell-free circulating DNA (cfDNA) is probably the most promising tool with respect to the identification of minimal residual diseases, assessment of treatment response and prognosis, and identification of resistance mechanisms. Circulating cell-free tumor DNA (ctDNA) maintains the same genomic signatures that are present in the matching tumor tissue allowing for the quantitative and qualitative evaluation of mutation burdens in body fluids. Thus, ctDNA-based research represents a non-invasive method for cancer detection. Among the numerous possible applications, the diagnostic, predictive, and/or prognostic utility of ctDNA in CRC has attracted intense research during the last few years. In the present review, we will describe the different aspects related to cfDNA research and evidence from studies supporting its potential use in CRC diagnoses and the improvement of therapy efficacy. We believe that ctDNA-based research should be considered as key towards the introduction of personalized medicine and patient benefits.

The Fear-Avoidance Components Scale (FACS): Responsiveness to Functional Restoration Treatment in a Chronic Musculoskeletal Pain Disorder (CMPD) Population

OBJECTIVES

To assess the clinical validity and factor structure of the Fear-Avoidance Components Scale (FACS), a new fear-avoidance measure.

MATERIALS AND METHODS

In this study, 426 chronic musculoskeletal pain disorder patients were admitted to a Functional Restoration Program (FRP). They were categorized into 5 FACS severity levels, from subclinical to extreme, at admission, and again at discharge. Associations with objective lifting performance and other patient-reported psychosocial measures were determined at admission and discharge, and objective work outcomes for this predominantly disabled cohort, were assessed 1 year later.

RESULTS

Those patients in the severe and extreme FACS severity groups at admission were more likely to "drop out" of treatment than those in the lower severity groups (P=0.05). At both admission and discharge, the FACS severity groups were highly and inversely correlated with objective lifting performance and patient-reported fear-avoidance-related psychosocial variables, including kinesiophobia, pain intensity, depressive symptoms, perceived disability, perceived injustice, and insomnia (Ps<0.001). All variables showed improvement at FRP discharge. Patients in the extreme FACS severity group at discharge were less likely to return to, or retain, work 1 year later (P≤0.02). A factor analysis identified a 2-factor solution.

DISCUSSION

Strong associations were found among FACS scores and other patient-reported psychosocial and objective lifting performance variables at both admission and discharge. High discharge-FACS scores were associated with worse work outcomes 1 year after discharge. The FACS seems to be a valid and clinically useful measure for predicting attendance, physical performance, distress, and relevant work outcomes in FRP treatment of chronic musculoskeletal pain disorder patients.

Immune Condition of Colorectal Cancer Patients Featured by Serum Chemokines and Gene Expressions of CD4+ Cells in Blood

BACKGROUND

Colorectal cancer (CRC), the most common malignancy worldwide, causes inflammation. We explored the inflammatory pathophysiology of CRC by assessing the peripheral blood parameters.

METHODS

The differences in gene expression profiles of whole blood cells and cell subpopulations between CRC patients and healthy controls were analyzed using DNA microarray. Serum cytokine/chemokine concentrations in CRC patients and healthy controls were measured via multiplex detection immunoassays. In addition, we explored correlations between the expression levels of certain genes of peripheral CD4+ cells and serum chemokine concentrations.

RESULTS

The gene expression profiles of peripheral CD4+ cells of CRC patients differed from those of healthy controls, but this was not true of CD8+ cells, CD14+ cells, CD15+ cells, or CD19+ cells. Serum IL-8 and eotaxin-1 levels were significantly elevated in CRC patients, and the levels substantially correlated with the expression levels of certain genes of CD4+ cells. Interestingly, the relationships between gene expression levels in peripheral CD4+ cells and serum IL-8 and eotaxin-1 levels resembled those of monocytes/macrophages, not T cells.

CONCLUSIONS

Serum IL-8 and eotaxin-1 concentrations increased and were associated with changes in the gene expression of peripheral CD4+ cells in CRC patients.

Diagnostic Value of Methylated Septin9 for Colorectal Cancer Screening: A Meta-Analysis

Background

Septin9 is a member of GTP-binding protein family, and is used as a predictive diagnostic index. However, it has not been widely adopted due to inconsistent results reported in the literature. The present study was performed to determine the diagnostic accuracy of methylated Septin9 (mSEPT9) for colorectal cancer (CRC) and to evaluate its utility in CRC screening.

Material/Methods

After reviewing relevant studies, accuracy measures (pooled sensitivity and specificity, positive/negative likelihood ratio [PLR/NLR], and diagnostic odds ratio [DOR]) were calculated for mSEPT9 in the diagnosis of CRC. Overall test performance was summarized using summary receiver operating characteristic curve analysis. Potential between-study heterogeneity was explored by use of a meta-regression model. We divided included studies into Epi proColon test and non-Epi proColon test subgroups. We compared the effects of mSEPT9 and fecal occult blood test (FOBT) for CRC screening.

Results

A total of 9870 subjects in 14 studies were recruited. Pooled sensitivity and specificity, PLR, NLR, DOR, and corresponding 95% confidence intervals (CI) of mSEPT9 for CRC diagnosis were 0.66 (95% CI: 0.64–0.69), 0.91 (95% CI: 0.90–0.91), 5.59 (95% CI: 4.03–7.74), 0.37 (95% CI: 0.29–0.48), and 16.79 (95% CI: 10.54–26.76), respectively. The area under the summary ROC curve (AUC) was 0.8563. The AUCs in the Epi proColon test and non-Epi proColon test for CRC diagnosis were 0.8709 and 0.7968, respectively. In head-to-head comparison, AUC of mSEPT9 and FOBT for CRC diagnosis were 0.7857 and 0.6571, respectively.

Conclusions

The present study demonstrates that mSEPT9 can be a good diagnostic biomarker complementary to FOBT as a screening tool for CRC.

Highly sensitive, non-invasive detection of colorectal cancer mutations using single molecule, third generation sequencing

Colorectal cancer (CRC) represents one of the most prevalent and lethal malignant neoplasms and every individual of age 50 and above should undergo regular CRC screening. Currently, the most effective preventive screening procedure to detect adenomatous polyps, the precursors to CRC, is colonoscopy. Since every colorectal cancer starts as a polyp, detecting all polyps and removing them is crucial. By exactly doing that, colonoscopy reduces CRC incidence by 80%, however it is an invasive procedure that might have unpleasant and, in rare occasions, dangerous side effects. Despite numerous efforts over the past two decades, a non-invasive screening method for the general population with detection rates for adenomas and CRC similar to that of colonoscopy has not yet been established. Recent advances in next generation sequencing technologies have yet to be successfully applied to this problem, because the detection of rare mutations has been hindered by the systematic biases due to sequencing context and the base calling quality of NGS. We present the first study that applies the high read accuracy and depth of single molecule, real time, circular consensus sequencing (SMRT-CCS) to the detection of mutations in stool DNA in order to provide a non-invasive, sensitive and accurate test for CRC. In stool DNA isolated from patients diagnosed with adenocarcinoma, we are able to detect mutations at frequencies below 0.5% with no false positives. This approach establishes a foundation for a non-invasive, highly sensitive assay to screen the population for CRC and the early stage adenomas that lead to CRC.

Diagnostic value of interleukin-8 in colorectal cancer: a case-control study and meta-analysis

AIM

To assess the diagnostic value of serum interleukin-8 (IL-8) in the detection of colorectal cancer (CRC).

METHODS

An original study was conducted to explore the potential value of IL-8 in CRC diagnosis. Receiver operating characteristic (ROC) analysis was performed and the area under the curve (AUC) value was calculated. PUBMED and EMBASE were searched (to October, 2013), supplemented with manual screening for relevant publications. Meta-analysis methods were applied to pool sensitivity, specificity, positive and negative likelihood ratios, and diagnostic odds ratios and to construct a summary receiver-operating characteristic (sROC) curve. Heterogeneity across studies was checked by the I(2) test and Deek's funnel plot method was applied to test publication bias.

RESULTS

In our original study, serum IL-8 yielded an AUC of 0.742 [95%CI: 0.635-0.849]. The sensitivity and specificity were 85.42% and 54.05%, respectively, at a cut-off value of 5.39. In this meta-analysis, we included five studies with 668 CRC patients and 374 controls and one study in our own center with 48 CRC patients and 37 controls. The pooled sensitivity and specificity of IL-8 were 0.69 (95%CI: 0.42-0.87) and 0.85 (95%CI: 0.68-0.94) for CRC detection. Besides, the area under the sROC curve was 0.86 (95%CI: 0.82-0.88). Subgroup analysis suggested that there was no heterogeneity in the Asian subgroup but some in the European subgroup. In addition, no publication bias was found according to the Deek's funnel plot asymmetry test.

CONCLUSION

Serum IL-8 is a promising biomarker for CRC detection and may become a clinically useful tool to identify high-risk patients.

Immune mediators as potential diagnostic tools for colorectal cancer: from experimental rationale to early clinical evidence

At the tumor site, solid tumors recruit native and adaptive infiltrating cell subtypes with a unique pattern, varying according to the organ of origin and the stage of the disease, which contributes to the complexity of the cancer microenvironment. The recruitment and activation of immune cells depend on a plethora of soluble immune mediators, including cytokines and chemokines that have a critical role in the process of cancer onset and progression. In colorectal cancer, measurement of soluble immune mediators in the serum seems to reflect the specific inflammatory reaction at the tumor site, and thus they might serve in clinical practice to improve available colorectal cancer detection and screening strategies. Clinical translation of data from experimental models could lead to the earlier detection of colorectal cancer resulting in a decreased burden of metastatic disease. These models and the most promising candidates for immune-based serum screening tests in colorectal cancer are discussed here.

Molecular Diagnostic Applications in Colorectal Cancer

Colorectal cancer, a clinically diverse disease, is a leading cause of cancer-related death worldwide. Application of novel molecular diagnostic tests, which are summarized in this article, may lead to an improved survival of colorectal cancer patients.  Distinction of these applications is based on the different molecular principles found in colorectal cancer (CRC). Strategies for molecular analysis of single genes (as KRAS or TP53) as well as microarray based techniques are discussed. Moreover, in addition to the fecal occult blood testing (FOBT) and colonoscopy some novel assays offer approaches for early detection of colorectal cancer like the multitarget stool DNA test or the blood-based Septin 9 DNA methylation test. Liquid biopsy analysis may also exhibit great diagnostic potential in CRC for monitoring developing resistance to treatment. These new diagnostic tools and the definition of molecular biomarkers in CRC will improve early detection and targeted therapy of colorectal cancer.

Can an alert in primary care electronic medical records increase participation in a population-based screening programme for colorectal cancer? COLO-ALERT, a randomised clinical trial

BACKGROUND

Colorectal cancer is an important public health problem in Spain. Over the last decade, several regions have carried out screening programmes, but population participation rates remain below recommended European goals. Reminders on electronic medical records have been identified as a low-cost and high-reach strategy to increase participation. Further knowledge is needed about their effect in a population-based screening programme. The main aim of this study is to evaluate the effectiveness of an electronic reminder to promote the participation in a population-based colorectal cancer screening programme. Secondary aims are to learn population's reasons for refusing to take part in the screening programme and to find out the health professionals' opinion about the official programme implementation and on the new computerised tool.

METHODS/DESIGN

This is a parallel randomised trial with a cross-sectional second stage.

PARTICIPANTS

all the invited subjects to participate in the public colorectal cancer screening programme that includes men and women aged between 50-69, allocated to the eleven primary care centres of the study and all their health professionals. The randomisation unit will be the primary care physician. The intervention will consist of activating an electronic reminder, in the patient's electronic medical record, in order to promote colorectal cancer screening, during a synchronous medical appointment, throughout the year that the intervention takes place. A comparison of the screening rates will then take place, using the faecal occult blood test of the patients from the control and the intervention groups. We will also take a questionnaire to know the opinions of the health professionals. The main outcome is the screening status at the end of the study. Data will be analysed with an intention-to-treat approach.

DISCUSSION

We expect that the introduction of specific reminders in electronic medical records, as a tool to facilitate and encourage direct referral by physicians and nurse practitioners to perform colorectal cancer screening will mean an increase in participation of the target population. The introduction of this new software tool will have good acceptance and increase compliance with recommendations from health professionals.

TRIAL REGISTRATION

Clinical Trials.gov identifier NCT01877018.

Assessing awareness of colorectal cancer symptoms and screening in a peripheral colorectal surgical unit: a survey based study

BACKGROUND

The National Screening Program for colorectal cancer is scheduled to commence in the near future. Previous studies on the topic of colorectal cancer and screening have highlighted paucity in public awareness of epidemiology, symptoms and signs of colorectal cancer. The aim of this study was to assess understanding of colorectal cancer and screening in a representative sample of the local catchment population of Mayo General Hospital.

METHODS

A prospective cohort study was instituted utilising an anonymous survey, which was distributed at consecutive general surgical out-patient clinics over a one month period prior to initiation of the screening program. Data collected included demographics, presenting complaint type and duration, and general knowledge of colorectal cancer facts. Attitudes towards screening were also evaluated.

RESULTS

Eighty-eight of the one hundred and thirty six patients sampled were female (65%). Thirty-six per cent of the sample was within the screening target age-group (55-74), with mean age 53 years (+/-18). Most respondents recognised bleeding per rectum as a possible symptom of colorectal cancer. A significant proportion, however, incorrectly selected less sinister symptoms as concerning, while only fifty per cent correctly cited weight loss. Family history was acknowledged as a risk factor by fifty-seven per cent with age and gender cited less often (29%, 4%), while forty-seven per cent incorrectly cited stress as a risk. Screening was defined as testing of symptomatic patients or those with a positive family history by eighty-one per cent of respondents, with only nineteen per cent associating screening with an asymptomatic cohort. Strikingly, twenty-five per cent of patients would decline screening.

CONCLUSIONS

There remains poverty of awareness regarding colorectal cancer. More public health initiatives are required to help improve understanding of the disease process, and to improve public compliance with the screening initiative.

[Attitudes of primary health care users to a colorectal cancer screening program]

OBJECTIVE

To describe the cultural, social and gender features that determine attitudes to colorectal cancer screening in a target group of patients aged 50 to 69 years old in the primary health care setting.

METHODS

We performed a qualitative ethnographic study from a gender perspective. Participants consisted of men and women aged 50 to 69 years old in the Balearic Islands and Barcelona. Group discussion and a field diary were used.

RESULTS

The key element was diagnosis at an early stage. Until recently, cancer was considered an incurable disease but is currently perceived as a serious health problem that can be cured if diagnosed promptly. The participants requested more information on cancer and felt they were at risk, mainly because of their age. Men tended to pay attention to symptoms while women tended to ignore them. Attitudes to colorectal cancer screening were generally positive, even to colonoscopy. Some barriers to screening were identified in women, such as a fear of having cancer.

CONCLUSIONS

The opportunity for early diagnosis is the key element in promoting participation in a colorectal cancer screening program. Perceptions-and hence willingness to participate in screening-differ between men and women. Factors to be taken into account in the design of population-based colorectal cancer programs are health concerns in men and fear of a cancer diagnosis in women.

Screening for colorectal cancer: how can we maximize uptake?

SUMMARY Screening for colorectal cancer is being introduced in a number of countries, yet uptake remains low. The rationalistic model of screening participation explains low uptake in terms of deficient knowledge and high cost. There is evidence to support this view and remedial actions produce anticipated effects up to a point. However, differential uptake among specific groups suggests that the individual decision to participate in screening is idiosyncratic, and understanding decisions requires interpretation in terms of message framing, reference points, the use of simplifying heuristics and affective or emotional reaction. As these aspects of decisions originate from fundamental personal characteristics, they may be difficult to combat. When decision determinants, such as fear and herding, are manipulated, consequences for uptake can be contradictory.

Awareness and attitudes of Greek medical students on colorectal cancer screening

AIM: To prospectively assess the knowledge and attitudes of medical students (MS), as tomorrow’s physicians, about colorectal cancer (CRC) and its screening modalities.

METHODS: Three hundred fourth year MS of the University of Athens were enrolled in this survey. Their selection was random, based on student identification card number. All participants completed an anonymous written questionnaire over a 4 month period. The questionnaire was divided into 4 sections and included queries about CRC-related symptoms, screening with colonoscopy and MS awareness and attitudes in this field. Following collection and analysis of the data, the results are presented as percentages of answers for each separate question.

RESULTS: Two hundred and sixty-five students answered the questionnaire over a 4 mo period. Interestingly, only 69% of the study population considered CRC to be a high-risk condition for public health. However, the vast majority of participants identified CRC-related symptoms and acknowledged its screening to be of great value in reducing CRC incidence and mortality. A very small proportion (38%) had received information material regarding CRC screening (either during their medical training or as a part of information provided to the general public) and only 60% of the participants declared willingness to receive further information. Regarding colonoscopy, 85% would prefer an alternative to colonoscopy methods for CRC screening. Moreover, 53% considered it to be a painful method and 68% would appreciate more information about the examination.

CONCLUSION: MS in Greece need to be better informed about CRC screening and screening colonoscopy.

A novel multiplex-protein array for serum diagnostics of colon cancer: a case-control study

BACKGROUND

More than 1.2 million new cases of colorectal cancer are reported each year worldwide. Despite actual screening programs, about 50% of the patients are diagnosed at advanced tumor stages presenting poor prognosis. Innovative screening tools could aid the detection at early stages and allow curative treatment interventions.

METHODS

A nine target multiplex serum protein biochip was generated and evaluated using a training- and validation-set of 317 highly standardized, liquid nitrogen preserved serum samples comprising controls, adenomas, and colon cancers.

RESULTS

Serum levels of CEA, IL-8, VEGF, S100A11, MCSF, C3adesArg, CD26, and CRP showed significant differences between cases and controls. The largest areas under the receiver operating characteristics curve were observed for CEA, IL-8, and CRP. At threshold levels yielding 90% specificity, sensitivities for CEA, IL-8 and CRP were 26%, 22%, and 17%, respectively. The most promising marker combinations were CEA + IL-8 reaching 37% sensitivity at 83% specificity and CEA + CRP with 35% sensitivity at 81% specificity. In an independent validation set CEA + IL-8 reached 47% sensitivity at 86% specificity while CEA + CRP obtained 39% sensitivity at 86% specificity. Early carcinomas were detected with 33% sensitivity for CEA + IL-8 and 28% for CEA + CRP.

CONCLUSIONS

Apart from CEA, IL-8, and CRP, the screening value of additional blood markers and the potential advantage of combining serum biochip testing with fecal occult blood testing needs to be studied. Multiplex biochip array technology utilizing serum samples offers an innovative approach to colorectal cancer screening.