Screening for colorectal cancer with immunochemical faecal occult blood tests

Emerging Designs of Electronic Devices in Biomedicine

A long-standing goal of nanoelectronics is the development of integrated systems to be used in medicine as sensor, therapeutic, or theranostic devices. In this review, we examine the phenomena of transport and the interaction between electro-active charges and the material at the nanoscale. We then demonstrate how these mechanisms can be exploited to design and fabricate devices for applications in biomedicine and bioengineering. Specifically, we present and discuss electrochemical devices based on the interaction between ions and conductive polymers, such as organic electrochemical transistors (OFETs), electrolyte gated field-effect transistors (FETs), fin field-effect transistor (FinFETs), tunnelling field-effect transistors (TFETs), electrochemical lab-on-chips (LOCs). For these systems, we comment on their use in medicine.

A stitch in time saves nine: Perceptions about colorectal cancer screening after a non-cancer colonoscopy result. Qualitative study

OBJECTIVES

To explore perceptions of colorectal cancer (CRC) screening among participants who have experienced a 'false alarm' for CRC, and to explore perceptions about the relevance of screening for themselves or others.

METHODS

Semi-structured interviews with screening participants who had participated in the Danish CRC screening program and experienced a 'false alarm' for colorectal cancer. A thematic analysis was performed, based on an interpretive tradition of ethnography.

RESULTS

Perceptions about CRC screening after a non-cancer colonoscopy result were characterized by trust in the colonoscopy result showing no CRC, and satisfaction with the screening offer despite the risk for 'false alarm'. The patient-involving behavior of the healthcare professionals during the examination was for most participants a cornerstone for trusting the validity of the colonoscopy result showing no CRC. Strong notions about perceived obligation to participate in screening were common.

CONCLUSIONS

Prominent themes were trust in the result, satisfaction with the procedure, and moral obligations to participate both for themselves and for others.

PRACTICE IMPLICATIONS

Information to future invitees after a 'false alarm' experience could build on peoples' trust in the validity of a previous non-cancer result and should underscore the importance of subsequent screening even after a 'false alarm' for cancer.

Faecal Occult Blood Point-of-Care Tests

Background

Early detection of colorectal cancer decreases the risk of mortality. Faecal occult blood tests (FOBT) are recognised as a useful tool for colorectal cancer screening. These non-invasive, rapid, and easy-to-carry assays are very often used as a point-of-care test and for self-testing. On the market, there are various types of FOB tests available, including chemical and immunochromatographic tests, which are based on different detection methods and differ in their sensitivity and specificity.

Conclusions

Clinicians should be aware of the causes of false-negative and false-positive test results, which can vary depending on the test. Additionally, stool sampling bias may be a source of error and must be considered by the clinician. The current FOBT methods are subject to various interfering factors; items such as proper preparation of the patient prior to testing or the clinician’s knowledge of testing limitations are key in correct interpreting results. Novel technologies such as FOBT DNA tests, micro RNA tests, and biochips equipped with bacteria can indicate bleeding from the gastrointestinal tract and improve diagnostics process.

Outcomes following polypectomy for malignant colorectal polyps are similar to those following surgery in the general population

OBJECTIVE

Population-based studies on colorectal malignant polyps (MPs) are scarce. The aim of this study was to describe time trends in the incidence of colorectal MPs before and after the introduction of a colorectal mass-screening programmein 2003 and to assess outcomes (survival and recurrence) after endoscopic or surgical resection in patients with MPs.

DESIGN

We included 411 patients with MPs diagnosed between 1982 and 2011 in a well-defined population. Age-standardised incidence rates were calculated. Univariate and multivariate 5-year recurrence and net survival analyses were performed according to gross morphology.

RESULTS

Age-standardised incidence of MPs in patients aged 50-74 years doubled from 5.4 in 1982-2002 to 10.9 per 100 000 in 2003-2011. Pedunculated MPs were more frequently resected endoscopically (38.2%) than were sessile MPs (19.1%; p<0.001). For patients with pedunculated MPs and a pathological margin ≥1 mm, the 5 -year cumulative recurrence rate did not differ significantly between surgical and endoscopic resection (8.2% and 2.4%, respectively). For patients with sessile MPs, it was 3.0% after first-line or second-line surgical resection, 8.6% after endoscopic resection and 17.9% after transanal resection (p=0.016). The recurrence rate decreased dramatically for patients with sessile MPs from 11.3% (1982-2002) to 1.2% (2003-2009) (p=0.010) and remained stable for pedunculated MPs at 4.6% and 6.7%, respectively. Five-year net survival was 81.0% when pathological margins were <1 mm and 95.6% when ≥1 mm (p=0.024).

CONCLUSION

Outcomes following polypectomy in patients with a pathological margin ≥1 mm are similar to those following surgery in the general population. Endoscopic resection needs to be completed by surgery if pathological margins are less than 1 mm.

Faecal occult blood screening for colorectal cancer in Serbia: a pilot study

Colorectal cancer (CRC) is becoming a major public health problem in the Republic of Serbia. Organized mass screening has been shown to decrease CRC mortality and even its incidence. The aim of this study was to assess the acceptability of a faecal immunochemical test for haemoglobin proposed by primary care physicians. From August to November 2013, a pilot study for CRC screening was organized in individuals aged 50 to 74 years. The study included 50 primary healthcare centres from all 25 administrative regions of Serbia. A qualitative immunochromatographic faecal immunochemical test for human haemoglobin detection was used. Overall, 50 894 individuals were invited. The participation rate was 67.8 and 3.4% of the tests were positive. Among individuals with a positive test, 69.7% agreed to undergo colonoscopy. The positive predictive value was 27.1% for adenoma and 14.6% for carcinoma. This was the first CRC screening project encompassing approximately one-third of primary healthcare facilities in all regions across the country. It showed a good response of the target population and satisfactory cooperation of the healthcare professionals involved.

Waiting for diagnostic colonoscopy: a qualitative exploration of screening participants' experiences in a FIT-based colorectal cancer screening program

BACKGROUND

Participants in population-based screening for colorectal cancer (CRC) may experience increased anxiety immediately after a positive screening test, but research in this area is limited. The objective of this study was to explore how screening participants experience a positive test result and cope with the pre-diagnostic waiting period in a CRC screening program.

MATERIALS AND METHODS

Screening participants with a positive fecal immunochemical test (FIT) result were identified in the Danish national CRC program before they attended diagnostic colonoscopy. Sixteen screening participants were selected for an interview in their own homes, using a semi-structured interview guide. Transcribed data were analyzed thematically.

RESULTS

The most prominent themes were symptom appraisal and communication strategies. Most participants attributed the positive FIT result showing blood in the stool to pre-existing non-malignant conditions but a few were very worried about the FIT result and the outcome of the colonoscopy. Communication strategies included discussions with family or friends about the positive FIT result and the upcoming colonoscopy, or containing information until the colonoscopy had provided the definitive diagnostic result. There was no apparent need for communication with health care professionals during the pre-diagnostic waiting period.

CONCLUSION

The pre-diagnostic waiting period between positive FIT result and colonoscopy in a population-based screening program may cause worry for some participants, potentially to require support, but most people consider it unconcerning. Screening providers should communicate to all screening participants in written form that negative emotional responses may occur after a positive screening result. This is particularly important in screening programs using self-sample kits without the presence of a health care professional to reassure the few participants who may experience significant anxiety.

Additional mailing phase for FIT after a medical offer phase: The best way to improve compliance with colorectal cancer screening in France

BACKGROUND

Compliance with colorectal cancer screening is critical to its effectiveness. The organisation of the mass screening programme in France has recently been modified with no evaluation of the consequences.

AIMS

To evaluate the impact of the way the screening test is delivered on compliance.

PATIENTS AND METHODS

During the first six months of the screening campaign (Ille-Vilaine, Brittany), general practitioners were asked to propose a faecal immunochemical test (FIT), OC-Sensor, to individuals at average risk for colorectal cancer (n=152,097). A subset of non-participants in the medical phase (n=13,071) was randomly chosen to receive a reminder that included the screening test or a simple postal reminder without the screening test.

RESULTS

Compliance was 31% if the screening test was proposed during a medical consultation. In non-participants during the medical phase, it was 45% in those receiving both a reminder and the screening test and 28% amongst those receiving a simple reminder. An estimated overall participation rate of 54% can be expected if non-participants in the medical phase are sent a reminder together with the screening test.

CONCLUSION

In France, a compliance rate above the minimum uptake rate of 45% recommended by European Union experts can be achieved if the FIT is mailed to non-participants after the medical free-offer phase.

The Effect of Educational Intervention on the Patient's Willingness to Carry out the Immunochemical Faecal Occult Blood Test for Colorectal Cancer

Background

There is now compelling evidence that screening for colorectal cancer may result in significantly reduced mortality. Screening tests for colorectal cancer are not systematically performed in Bulgaria.

Aim

This article explores the effect of an educational intervention on the willingness of patients to participate in the screening for colorectal cancer with the immunochemical faecal occult blood test in the home setting.

Materials and methods

A before-after design study of the effects of educational intervention comprising distribution of a brochure and one-to-one discussion with a GP. A self-administered, original questionnaire was administered before and after the intervention to 600 randomly selected patients in 40 general practices (15 patients per practice) in Plovdiv district.

Results

The intervention led to an increase with >20% of the patient’s knowledge of the importance of the test and on how to carry out the test. Statistical analysis indicated that there was an increase in knowledge after the educational intervention about the usefulness of the test (24.8% in males, 18.3% in females) and its performance (22.7% in males, 25.4% in females).

Conclusion

The educational intervention has significantly influenced the patient’s awareness about the test’s usefulness and its self-administration. It improved the awareness by providing an easy access to information, thus fostering the active involvement of the patients. A strength of the intervention was the patient-centered approach in providing additional information through one-to-one discussions, and it ensured a higher quality of the preventive screening in the general practice.

Protocol Outlines for Parts 1 and 2 of the Prospective Endoscopy III Study for the Early Detection of Colorectal Cancer: Validation of a Concept Based on Blood Biomarkers

BACKGROUND

Programs for population screening of colorectal cancer (CRC) have been implemented in several countries with fecal immunochemical testing (FIT) as the preferred platform. However, the major obstacle for a feces-based testing method is the limited compliance that reduces the clinical sensitivity for detection of participants with non-symptomatic CRC. Therefore, research approaches have been initiated to develop screening concepts based on biomarkers in blood. Preliminary results show that protein, genetic, epigenetic, and metabolomic components may be valuable in blood-based screening concepts, particularly when combinations of the various components appear to lead to significant improvements.

OBJECTIVES

The protocol described in this paper focuses on the validation of concepts based on biomarkers in blood in a major population screened by FIT.

METHODS

In Part 1, participants will be identified and included through the Danish CRC Screening Program comprising initial FIT and subsequent colonoscopy to those with a positive result. Blood samples will be collected from 8000 FIT-positive participants, who are offered subsequent colonoscopy. Findings and interventions at colonoscopy together with personal data including co-morbidity will be recorded. Blood samples and data will also be collected from 6000 arbitrarily chosen participants with negative FIT. In Part 2, blood samples and data will be collected from 30,000 FIT-negative participants three times within 4 years. The blood samples will be analyzed using various in-house and commercially available manual and automated analysis platforms.

RESULTS

We anticipate Part 1 to terminate late August 2016 and Part 2 to terminate late September 2022. The results from Parts 1 and 2 will be presented within 12 to 18 months from termination.

CONCLUSIONS

The purpose of this study is to improve the efficacy of identifying participants with neoplastic bowel lesions, to identify false negative participants, to identify participants at risk of interval neoplastic lesions, to improve the compliance in screening sessions, and to establish guidelines for out-patient follow-up of at-risk participants based on combinations of blood-based biomarkers.

Familial colorectal cancer screening: When and what to do?

Colorectal cancer (CRC) is the third leading cause of death worldwide and represents a clinical challenge. Family members of patients affected by CRC have an increased risk of CRC development. In these individuals, screening is strongly recommended and should be started earlier than in the population with average risk, in order to detect neoplastic precursors, such as adenoma, advanced adenoma, and nonpolypoid adenomatous lesions of the colon. Fecal occult blood test (FOBT) is a non invasive, widespread screening method that can reduce CRC-related mortality. Sigmoidoscopy, alone or in addition to FOBT, represents another screening strategy that reduces CRC mortality. Colonoscopy is the best choice for screening high-risk populations, as it allows simultaneous detection and removal of preneoplastic lesions. The choice of test depends on local health policy and varies among countries.