The NHS Bowel Cancer Screening Program: current perspectives on strategies for improvement

Faecal immunochemical tests can improve colonoscopy triage in patients with iron deficiency: A systematic review and meta-analysis

BACKGROUND

Use of the faecal immunochemical test (FIT) to triage patients with iron deficiency (ID) for colonoscopy due to suspected colorectal cancer (CRC) may improve distribution of colonoscopic resources. We reviewed the diagnostic performance of FIT for detecting advanced colorectal neoplasia, including CRC and advanced pre-cancerous neoplasia (APCN), in patients with ID, with or without anaemia.

METHODS

We performed a systematic review of three databases for studies comprising of patients with ID, with or without anaemia, completing a quantitative FIT within six months prior to colonoscopy, where test performance was compared against the reference standard colonoscopy. Random effects meta-analyses determined the diagnostic performance of FIT for advanced colorectal neoplasia.

RESULTS

Nine studies were included on a total of n=1761 patients with ID, reporting FIT positivity thresholds between 4-150 µg haemoglobin/g faeces. Only one study included a non-anaemic ID (NAID) cohort. FIT detected CRC and APCN in ID patients with 90.7 % and 49.3 % sensitivity, and 81.0 % and 82.4 % specificity, respectively. FIT was 88.0 % sensitive and 83.4 % specific for CRC in patients with ID anaemia at a FIT positivity threshold of 10 µg haemoglobin/g faeces.

CONCLUSIONS

FIT shows high sensitivity for advanced colorectal neoplasia and may be used to triage those with ID anaemia where colonoscopic resources are limited, enabling those at higher risk of CRC to be prioritised for colonoscopy. There is a need for further research investigating the diagnostic performance of FIT in NAID patients.

Colorectal cancer risk stratification using a polygenic risk score in symptomatic primary care patients-a UK Biobank retrospective cohort study

Colorectal cancer (CRC) is a leading cause of cancer mortality worldwide. Accurate cancer risk assessment approaches could increase rates of early CRC diagnosis, improve health outcomes for patients and reduce pressure on diagnostic services. The faecal immunochemical test (FIT) for blood in stool is widely used in primary care to identify symptomatic patients with likely CRC. However, there is a 6-16% noncompliance rate with FIT in clinic and ~90% of patients over the symptomatic 10 µg/g test threshold do not have CRC. A polygenic risk score (PRS) quantifies an individual's genetic risk of a condition based on many common variants. Existing PRS for CRC have so far been used to stratify asymptomatic populations. We conducted a retrospective cohort study of 50,387 UK Biobank participants with a CRC symptom in their primary care record at age 40+. A PRS based on 201 variants, 5 genetic principal components and 22 other risk factors and markers for CRC were assessed for association with CRC diagnosis within 2 years of first symptom presentation using logistic regression. Associated variables were included in an integrated risk model and trained in 80% of the cohort to predict CRC diagnosis within 2 years. An integrated risk model combining PRS, age, sex, and patient-reported symptoms was predictive of CRC development in a testing cohort (receiver operating characteristic area under the curve, ROCAUC: 0.76, 95% confidence interval: 0.71-0.81). This model has the potential to improve early diagnosis of CRC, particularly in cases of patient noncompliance with FIT.

Risk assessment in pT1 colorectal cancer

Colorectal cancer (CRC) is a common malignancy worldwide and tumour stage is closely related to clinical outcome. A small but significant proportion of submucosal-invasive (ie, pT1) CRC are associated with regional lymph node metastases (LNM) and a worse prognosis. The likelihood of LNM in pT1 CRC needs to be balanced against the operative risk and costs of surgical resection when determining the best patient management. A wide range of histopathological and clinical factors may affect LNM risk in this setting. This script provides a comprehensive overview of the tumour and patient-associated features that have been linked to LNM risk in pT1 CRC. Some of the features are well established within the literature and are included in published guidelines, while others are novel and emerging in nature. Odds ratios for LNM that are associated with key predictive features are provided where appropriate, and published models developed as an aid to the calculation of LNM risk are discussed.

The gut microbiota in adults with cystic fibrosis compared to colorectal cancer

BACKGROUND

Gut dysbiosis is implicated in colorectal cancer (CRC) pathogenesis. Cystic fibrosis (CF) is associated with both gut dysbiosis and increased CRC risk. We therefore compared the faecal microbiota from individuals with CF to CRC and screening samples. We also assessed changes in CRC-associated taxa before and after triple CF transmembrane conductance regulator (CFTR) modulator therapy.

METHODS

Bacterial DNA amplification comprising V4 16S rRNA analysis was conducted on 84 baseline and 53 matched follow-up stool samples from adults with CF. These data were compared to an existing cohort of 430 CRC and 491 control gFOBT samples from the NHS Bowel Cancer Screening Programme. Data were also compared to 26 previously identified CRC-associated taxa from a published meta-analysis.

RESULTS

Faecal CF samples had a lower alpha diversity and clustered distinctly from both CRC and control samples, with no clear clinical variables explaining the variation. Compared to controls, CF samples had an increased relative abundance in 6 of the 20 enriched CRC-associated taxa and depletion of 2 of the 6 taxa which have been reported as reduced in CRC. Commencing triple modulator therapy had subtle influence on the relative abundance of CRC-associated microbiota (n = 23 paired CF samples).

CONCLUSIONS

CF stool samples were clearly dysbiotic, clustering distinctly from both CRC and control samples. Several bacterial shifts in CF samples resembled those observed in CRC. Studies assessing the impact of dietary or other interventions and the longer-term use of CFTR modulators on reducing this potentially pro-oncogenic milieu are needed.

Evaluating the potential impact of lifestyle-based behavior change interventions delivered at the time of colorectal cancer screening

PURPOSE

To analyze interventions implemented at the time of colorectal cancer (CRC) screening, or among individuals who have previously undergone investigation for CRC, focused on reducing CRC risk through promotion of lifestyle behavior change. Additionally, this review evaluated to what extent such interventions apply behavior change techniques (BCTs) to achieve their objectives.

METHODS

Five databases were systematically searched to identify randomized control trials seeking to reduce CRC risk through behavior change. Outcomes were changes in health-related lifestyle behaviors associated with CRC risk, including changes in dietary habits, body mass index, smoking behaviors, alcohol consumption, and physical activity. Standardized mean differences (SMDs) with 95% confidence intervals (CIs) were pooled using random effects models. BCT's were coded from a published taxonomy of 93 techniques.

RESULTS

Ten RCT's met the inclusion criteria. Greater increase in fruit/vegetable consumption in the intervention group were observed with respect to the control (SMD 0.13, 95% CI 0.08 to 0.18; p < 0.001). Across fiber, alcohol, fat, red meat, and multivitamin consumption, and smoking behaviors, similar positive outcomes were observed (SMD 0.09-0.57 for all, p < 0.01). However, among physical activity and body mass index, no difference between the intervention groups compared with controls were observed. A median of 7.5 BCTs were applied across included interventions.

CONCLUSION

While magnitude of the observed effect sizes varied, they correspond to potentially important changes in lifestyle behaviors when considered on a population scale. Future interventions should identify avenues to maximize long-term engagement to promote sustained lifestyle behavior change.

Knowledge and Attitude of Inflammatory Bowel Disease Patients Toward Colorectal Cancer Risk, Its Management, and the Role of Healthcare Providers: A Cross-Sectional Study in the UK

Background

Inflammatory bowel disease (IBD) increases the risk for colorectal cancer (CRC). Limited literature exists on patients' knowledge of CRC risk and management. Attitude toward doctor-recommended management and the role of healthcare providers (HCPs) in CRC risk awareness remain unexplored. This study aimed to fill the gap in knowledge about CRC risk awareness and management in IBD patients in the UK.

Methods

This cross-sectional internet-based study was conducted in April-July 2019. Adult (>18 years) IBD patients with a confirmed diagnosis for 2 years and adequate command of English language were invited from non-Natinal Health Services sources. A self-designed and piloted questionnaire with open- and closed-ended questions was used. Closed-ended data were analyzed using descriptive statistics and open-ended responses were analyzed using content analysis.

Results

Ninety-two participants (52.5% Crohn's disease and 67.5% females) responded. Around 88% knew that IBD increased CRC risk. Only 20.7% were aware of colonoscopy as the best screening tool; 88% were unaware of screening initiation time. Almost 90% would agree to a doctor's recommendation of colonoscopy. For dysplasia with 10% risk of CRC, 46.7% would not agree with colectomy. Some 48% reported to have never had a discussion about the risk of CRC in IBD with their HCPs, while 58% were not informed of the role of screening and surveillance in managing CRC risk.

Conclusions

IBD patients were poorly aware of CRC risk management and had mixed willingness to comply with a doctor's recommendation. HCP's role in cancer knowledge dissemination was suboptimal and patients desired more information.

Colorectal cancer incidence trends by tumour location among adults of screening-age in England: a population-based study

AIM

Proximal and distal colorectal cancers (CRCs) exhibit different clinical, molecular and biological patterns. The aim of this study was to determine temporal trends in the age-standardized incidence rates (ASIRs) of proximal and distal CRC following the introduction of the English Bowel Cancer Screening Programme (BCSP) in 2006.

METHOD

The National Cancer Registration and Analysis Service database was used to identify incident cases of CRC among adults of screening age (60-74 years) between 2001 and 2017. ASIRs were calculated using the European Standard Population 2013 and incidence trends analysed by anatomical subsite (proximal, caecum to descending colon; distal, sigmoid to rectum), sex and Index of Multiple Deprivation (IMD) quintile using Joinpoint regression software.

RESULTS

Between 2001 and 2017, 541 515 incident cases of CRC were diagnosed [236 167 proximal (43.6%) and 305 348 distal (56.4%)]. A marginal reduction in the proximal ASIR was noted from 2008 [annual percentage change (APC) -1.4% (95% CI -2.0% to -0.9%)] compared with a greater reduction in distal ASIR from 2011 to 2014 [APC -6.6% (95% CI -11.5% to -1.5%)] which plateaued thereafter [APC -0.5% (95% CI -3.2% to 2.2%)]. Incidence rates decreased more rapidly in men than women. Adults in IMD quintiles 4-5 experienced the greatest reduction in distal tumours [APC -3.5% (95% CI -4.3% to -2.7%)].

CONCLUSION

Following the introduction of the English BCSP, the incidence of CRC has subsequently reduced among adults of screening age, with this trend being most pronounced in distal tumours and in men. There is also evidence of a reduction in the deprivation gap for distal tumour incidence. Strategies to improve the detection of proximal tumours are warranted.

Acceptability of alternative technologies compared with faecal immunochemical test and/or colonoscopy in colorectal cancer screening: A systematic review

OBJECTIVE

Colorectal cancer (CRC) is the third most common cancer and the second largest cause of cancer-related death worldwide. Current CRC screening in various countries involves stool-based faecal immunochemical testing (FIT) and/or colonoscopy, yet public uptake remains sub-optimal. This review assessed the literature regarding acceptability of alternative CRC screening modalities compared to standard care in average-risk adults.

METHOD

Systematic searches of MEDLINE, EMBASE, CINAHL, Cochrane and Web of Science were conducted up to February 3rd, 2022. The alternative interventions examined were computed tomography colonography, flexible sigmoidoscopy, colon capsule endoscopy and blood-based biomarkers. Outcomes for acceptability were uptake, discomfort associated with bowel preparation, discomfort associated with screening procedure, screening preferences and willingness to repeat screening method. A narrative data synthesis was conducted.

RESULTS

Twenty-one studies met the inclusion criteria. Differences between intervention and comparison modalities in uptake did not reach statistical significance in most of the included studies. The findings do suggest FIT as being more acceptable as a screening modality than flexible sigmoidoscopy. There were no consistent significant differences in bowel preparation discomfort, screening procedure discomfort, screening preference and willingness to repeat screening between the standard care and alternative modalities.

CONCLUSION

Current evidence comparing standard colonoscopy and stool-based CRC screening with novel modalities does not demonstrate any clear difference in acceptability. Due to the small number of studies available and included in each screening comparison and lack of observed differences, further research is needed to explore factors influencing acceptability of alternative CRC modalities that might result in improvement in population uptake within different contexts.

Effectiveness of behavioural economics-based interventions to improve colorectal cancer screening participation: A rapid systematic review of randomised controlled trials

•

We searched PubMed, PsycInfo and EconLit for RCTs that evaluated BE interventions in CRC screening.

•

We identified 1027 papers for title and abstract review. 30 studies were eligible for the review.

•

The most frequently tested BE intervention was incentives, followed by default principle and salience.

•

Default-based interventions were most likely to be effective. Incentives had mixed evidence.

•

BE remains a promising field of interest in relation to influencing CRC screening behaviours.

Using a dark logic model to explore adverse effects in audit and feedback: a qualitative study of gaming in colonoscopy

BACKGROUND

Audit and feedback (A&F) interventions improve patient care but may result in unintended consequences. To evaluate plausible harms and maximise benefits, theorisation using logic models can be useful. We aimed to explore the adverse effects of colonoscopy A&F using a feedback intervention theory (FIT) dark logic model before the National Endoscopy Database Automated Performance Reports to Improve Quality Outcomes Trial study.

METHODS

We undertook a qualitative study exploring A&F practices in colonoscopy. Interviews were undertaken with endoscopists from six English National Health Service endoscopy centres, purposively sampled for professional background and experience. A thematic framework analysis was performed, mapping paradoxical effects and harms using FIT and the theory of planned behaviour.

RESULTS

Data saturation was achieved on the 19th participant, with participants from nursing, surgical and medical backgrounds and a median of 7 years' experience.When performance was below aspirational targets participants were falsely reassured by social comparisons. Participants described confidence as a requirement for colonoscopy. Negative feedback without a plan to improve risked reducing confidence and impeding performance (cognitive interference). Unmet targets increased anxiety and prompted participants to question messages' motives and consider gaming.Participants described inaccurate documentation of subjective measures, including patient comfort, to achieve targets perceived as important. Participants described causing harm from persevering to complete procedures despite patient discomfort and removing insignificant polyps to improve detection rates without benefiting the patient.

CONCLUSION

Our dark logic model highlighted that A&F interventions may create both desired and adverse effects. Without a priori theorisation evaluations may disregard potential harms. In colonoscopy, improved patient experience measures may reduce harm. To address cognitive interference the motivation of feedback to support improvement should always be clear, with plans targeting specific behaviours and offering face-to-face support for confidence.

TRIAL REGISTRATION NUMBER

ISRCTN11126923.

Ability of known colorectal cancer susceptibility SNPs to predict colorectal cancer risk: A cohort study within the UK Biobank

Colorectal cancer risk stratification is crucial to improve screening and risk-reducing recommendations, and consequently do better than a one-size-fits-all screening regimen. Current screening guidelines in the UK, USA and Australia focus solely on family history and age for risk prediction, even though the vast majority of the population do not have any family history. We investigated adding a polygenic risk score based on 45 single-nucleotide polymorphisms to a family history model (combined model) to quantify how it improves the stratification and discriminatory performance of 10-year risk and full lifetime risk using a prospective population-based cohort within the UK Biobank. For both 10-year and full lifetime risk, the combined model had a wider risk distribution compared with family history alone, resulting in improved risk stratification of nearly 2-fold between the top and bottom risk quintiles of the full lifetime risk model. Importantly, the combined model can identify people (n = 72,019) who do not have family history of colorectal cancer but have a predicted risk that is equivalent to having at least one affected first-degree relative (n = 44,950). We also confirmed previous findings by showing that the combined full lifetime risk model significantly improves discriminatory accuracy compared with a simple family history model 0.673 (95% CI 0.664–0.682) versus 0.666 (95% CI 0.657–0.675), p = 0.0065. Therefore, a combined polygenic risk score and first-degree family history model could be used to improve risk stratified population screening programs.

Cervical screening attendance and cervical cancer risk among women who have sex with women

OBJECTIVES

To describe cervical cancer screening participation among women who have sex exclusively with women (WSEW) and women who have sex with women and men (WSWM) compared with women who have sex exclusively with men (WSEM), and women who have never had sex and compare this with bowel (colorectal) and breast screening participation. To explore whether there is evidence of differential stage 3 cervical intraepithelial neoplasia (CIN3) or cervical cancer risk.

METHODS

We describe cervical, bowel and breast cancer screening uptake in age groups eligible for the national screening programmes, prevalent CIN3 and cervical cancer at baseline, and incident CIN3 and cervical cancer at five years follow-up, among 218,674 women in UK Biobank, a cohort of healthy volunteers from the UK.

RESULTS

Compared with WSEM, in adjusted analysis [odds ratio (95% confidence interval)], WSEW 0.10 (0.08-0.13), WSWM 0.73 (0.58-0.91), and women who have never had sex 0.02 (0.01-0.02) were less likely to report ever having attended cervical screening. There were no differences when considering bowel cancer screening uptake (p = 0.61). For breast cancer screening, attendance was lower among WSWM 0.79 (0.68 to 0.91) and women who have never had sex 0.47 (0.29-0.58), compared with WSEM. There were incident and prevalent cases of both CIN3 and cervical cancer among WSEW and WSWM. Compared with WSEM with a single male partner, among WSEW there was a twofold increase in CIN3 1.91 (1.01 to 3.59); among WSWM with only one male partner, this was 2.25 (1.19 to 4.24).

CONCLUSIONS

These findings highlight the importance of improving uptake of cervical screening among all women who have sex with women and breast screening among WSWM and women who have never had sex.

Low Referral Rates for Genetic Assessment of Patients With Multiple Adenomas in United Kingdom Bowel Cancer Screening Programs

BACKGROUND

Approximately 1 in 20 cases of colorectal cancer are caused by monogenic syndromes. Published guidelines recommend that patients with 10 or more adenomas be referred for genetic testing, based on evidence that colorectal cancer risk is associated with adenoma multiplicity.

OBJECTIVE

The aim of this study was to determine adherence to guidelines on referral for genetic screening in patients with 10 or more adenomas.

DESIGN

A cross-sectional study was performed of prospectively collected data from the UK Bowel Cancer Screening Programme between May 2007 and June 2018. Only histologically confirmed adenomas were included. Clinicopathological data were recorded from patient records, and referrals to clinical genetics services were ascertained.

SETTING

Data were obtained from 3 centers in London, United Kingdom.

PATIENTS

A total of 17,450 subjects underwent colonoscopy following an abnormal fecal occult blood test.

MAIN OUTCOME MEASURES

We quantified patients with 10 or more adenomas and the proportion referred for genetic screening.

RESULTS

The adenoma detection rate was 50.6% among 17,450 patients who underwent colonoscopy (8831 had 1 or more adenomas). Three hundred forty-seven patients (2.0%) had 10 or more adenomas. Patients with 10 or more adenomas were more likely to be male than those with fewer than 10 adenomas (76.9% vs 53.4%; p < 0.0001). A family history was collected in 37.8% of the multiple adenoma population. Of 347 patients with 10 or more adenomas, 28 (8.1%) were referred for genetic assessment.

LIMITATIONS

All 3 screening centers were in a single city. No genetic outcome data were available to permit analysis of actual rates of inherited cancer syndromes in this population.

CONCLUSIONS

In this study, almost 1 in 50 patients had 10 or more adenomas. Despite guidelines advising genetic testing in this group, referral rates are low. A referral pathway and management strategies should be established to address this patient population. See Video Abstract at http://links.lww.com/DCR/B630.

TASAS BAJAS DE DERIVACIN PARA LA EVALUACIN GENTICA DE PACIENTES CON ADENOMAS MLTIPLES EN LOS PROGRAMAS DE DETECCIN DEL CNCER DE INTESTINO DEL REINO UNIDO

ANTECEDENTES:Aproximadamente uno de cada veinte casos de cáncer colorrectal son causados por síndromes monogénicos. Las pautas publicadas recomiendan que los pacientes con diez o más adenomas sean derivados para pruebas genéticas, basándose en la evidencia de que el riesgo de cáncer colorrectal está asociado con la multiplicidad de adenomas.OBJETIVO:El objetivo de este estudio fue determinar la adherencia a las guías de derivación para cribado genético en pacientes con diez o más adenomas.DISEÑO:Se realizó un estudio transversal de datos recolectados prospectivamente del Programa de Detección de Cáncer de Intestino del Reino Unido entre mayo de 2007 y junio de 2018. Solo se incluyeron los adenomas confirmados histológicamente. Los datos clínico-patológicos se registraron a partir de los registros de los pacientes y se determinaron las derivaciones a los servicios de genética clínica.AJUSTE ENTORNO CLINICO:Los datos se obtuvieron de tres centros en Londres, Reino Unido.PACIENTES:Un total de 17.450 17450 sujetos pacientes se sometieron a una colonoscopia después de una prueba de sangre oculta en heces anormal positiva.PRINCIPALES MEDIDAS DE RESULTADO VOLARACION:cuantificamos los pacientes con diez o más adenomas y la proporción remitida para cribado genético.RESULTADOS:La tasa de detección de adenomas fue del 50,6% entre 17.450 17450 pacientes que se sometieron a colonoscopia (8.831 8831 tenían uno o más adenomas). 347 pacientes (2,0%) tenían 10 o más adenomas. Los pacientes con 10 o más adenomas tenían más probabilidades de ser hombres que aquellos con menos de 10 adenomas (76,9% frente versus a 53,4%; p <0,0001). Se recogieron antecedentes familiares en el 37,8% de la población de adenomas múltiples. De 347 pacientes con 10 o más adenomas, 28 (8,1%) fueron remitidos para evaluación genética.LIMITACIONES:Los tres centros de detección se encontraban en una sola ciudad. No se disponía de datos de resultados genéticos que permitieran el análisis de las tasas reales de síndromes de cáncer hereditario en esta población.CONCLUSIONES:En este estudio, casi uno de cada cincuenta pacientes tenía diez o más adenomas. A pesar de las pautas que recomiendan las pruebas genéticas en este grupo, las tasas de derivación son bajas. Se debe establecer una vía de derivación y estrategias de manejo para abordar esta población de pacientes. Consulte Video Resumen en http://links.lww.com/DCR/B630.

Management of early rectal cancer; current surgical options and future direction

Rectal cancer is the second commonest cause of cancer death within the United Kingdom. Utilization of national screening programmes have resulted in a greater proportion of patients presenting with early-stage disease. The technique of transanal endoscopic microsurgery was first described in 1984 following which further options for local excision have emerged with transanal endoscopic operation and, more recently, transanal minimally invasive surgery. Owing to the risks of local recurrence, the current role of minimally invasive techniques for local excision in the management of rectal cancer is limited to the treatment of pre-invasive disease and low risk early-stage rectal cancer (T1N0M0 disease). The roles of chemotherapy and radiotherapy for the management of early rectal cancer are yet to be fully established. However, results of high-quality research such as the GRECCAR II, TESAR and STAR-TREC randomised control trials may highlight a wider role for local excision surgery in the future, when used in combination with oncological therapies. The aim of our review is to provide an overview in the current management of early rectal cancer, the surgical options available for local excision and the future multimodal direction of early rectal cancer treatment.

Physical activity advice in the UK bowel cancer screening setting: qualitative healthcare professional perspectives

Providing physical activity advice in the bowel cancer screening setting could help to reduce the risk of cancer and cardiometabolic disease in older adults. This study investigated the views of healthcare professionals (HCPs) regarding the provision of physical activity advice as part of the UK Bowel Cancer Screening Programme. A purposive sample of HCPs (aged 22-63 years, with 1-26 years of experience) from four bowel cancer screening disciplines (four endoscopists, four colorectal surgeons, four staff nurses and four specialist screening practitioners) were recruited from a large National Health Service gastroenterology unit. Data collection used individual interviews and focus groups, with topics being guided by an a priori topic guide. All interviews and focus groups were audio-recorded and transcribed verbatim. Three key themes, which contextualize the views and perceptions of HCPs recruited to the study, emerged from the framework analysis: (i) appraisal of the concept; (ii) perceived barriers to implementation; (iii) steps to implementation. While the general concept was viewed positively, there were differences of opinion and a range of perceived barriers were revealed. Ideas for effective implementation were also presented, taking into consideration the need for time efficiencies and importance of optimizing effectiveness. This qualitative study provided important insights into the perceptions of HCPs regarding the provision of physical activity advice in the bowel cancer screening setting, and yielded novel ideas for effective implementation.

Recognising Colorectal Cancer in Primary Care

Colorectal cancer (CRC) is the third most common cancer worldwide. Primary care professionals can play an important role in both prevention and early detection of CRC. Most CRCs are attributed to modifiable lifestyle factors, which can be addressed within primary care, and promotion of population-based screening programmes can aid early cancer detection in asymptomatic patients. Primary care professionals have a vital role in clinically assessing patients presenting with symptoms that may indicate cancer, as most patients with CRC first present with symptoms. These assessments are often challenging—many of the symptoms of CRC are non-specific and commonly occur in patients presenting with non-malignant disease. The range of options for investigating symptomatic patients in primary care is rapidly growing. Simple tests, such as faecal immunochemical testing (FIT), are now being used to guide decisions around referral for more invasive tests, such as colonoscopy, while direct access to specialist investigations is also becoming more common. Clinical decision support tools (CDSTs) which calculate cancer risk based on symptomatology, patient characteristics and test results can provide an additional resource to guide decisions on further investigation. This article explores the challenges of CRC prevention and detection from the primary care perspective, discusses current evidence-based approaches for CRC detection used in primary care (with examples from UK guidelines), and highlights emerging research which may likely alter practice in the future.

Canadian Colorectal Cancer Screening Guidelines: Do They Need an Update Given Changing Incidence and Global Practice Patterns?

Colorectal cancer (CRC) is the third most commonly diagnosed cancer and second leading cause of cancer death in Canada. Organized screening programs targeting Canadians aged 50 to 74 at average risk of developing the disease have contributed to decreased rates of CRC, improved patient outcomes and reduced healthcare costs. However, data shows that recent incidence reductions are unique to the screening-age population, while rates in people under-50 are on the rise. Similar incidence patterns in the United States prompted the American Cancer Society and U.S. Preventive Services Task Force to recommend screening begin at age 45 rather than 50. We conducted a review of screening practices in Canada, framing them in the context of similar global health systems as well as the evidence supporting the recent U.S. recommendations. Epidemiologic changes in Canada suggest earlier screening initiation in average-risk individuals may be reasonable, but the balance of costs to benefits remains unclear.

Microbiome Analysis of More Than 2,000 NHS Bowel Cancer Screening Programme Samples Shows the Potential to Improve Screening Accuracy

PURPOSE

There is potential for fecal microbiome profiling to improve colorectal cancer screening. This has been demonstrated by research studies, but it has not been quantified at scale using samples collected and processed routinely by a national screening program.

EXPERIMENTAL DESIGN

Between 2016 and 2019, the largest of the NHS Bowel Cancer Screening Programme hubs prospectively collected processed guaiac fecal occult blood test (gFOBT) samples with subsequent colonoscopy outcomes: blood-negative [n = 491 (22%)]; colorectal cancer [n = 430 (19%)]; adenoma [n = 665 (30%)]; colonoscopy-normal [n = 300 (13%)]; nonneoplastic [n = 366 (16%)]. Samples were transported and stored at room temperature. DNA underwent 16S rRNA gene V4 amplicon sequencing. Taxonomic profiling was performed to provide features for classification via random forests (RF).

RESULTS

Samples provided 16S amplicon-based microbial profiles, which confirmed previously described colorectal cancer-microbiome associations. Microbiome-based RF models showed potential as a first-tier screen, distinguishing colorectal cancer or neoplasm (colorectal cancer or adenoma) from blood-negative with AUC 0.86 (0.82-0.89) and AUC 0.78 (0.74-0.82), respectively. Microbiome-based models also showed potential as a second-tier screen, distinguishing from among gFOBT blood-positive samples, colorectal cancer or neoplasm from colonoscopy-normal with AUC 0.79 (0.74-0.83) and AUC 0.73 (0.68-0.77), respectively. Models remained robust when restricted to 15 taxa, and performed similarly during external validation with metagenomic datasets.

CONCLUSIONS

Microbiome features can be assessed using gFOBT samples collected and processed routinely by a national colorectal cancer screening program to improve accuracy as a first- or second-tier screen. The models required as few as 15 taxa, raising the potential of an inexpensive qPCR test. This could reduce the number of colonoscopies in countries that use fecal occult blood test screening.

Aspects of colorectal cancer screening, methods, age and gender

Colorectal cancer (CRC) is, besides breast, prostate, lung and skin cancers, the most common cancer worldwide and is suitable for screening. The incidence of CRC varies considerably in different parts of the world: in well-developed countries, the incidence is between 30 and 70 per 100 000 inhabitants, whereas in less-developed countries such as sub-Saharan Africa, it is 10-20/100 000 inhabitants. Women have a lower incidence of CRC, which is usually one-third of total incidence. Several studies have shown that it is possible to decrease mortality from CRC with about 20%, which is evidenced through the data from countries with screening programmes. Though the method of choice to identify blood samples in faecal matter is under debate, the most feasible way is to perform colonoscopy. Other methods include more advanced faecal analyses, testing for mutations from CRC, sigmoidoscopy, CT colonoscopy or optical colonoscopy. Colonoscopy is in most countries not available in sufficient amount and has to be carried out with great accuracy; otherwise, lesions will be missed to identify, thus leading to complications. Gender is an issue in CRC screening, as women have about 20% fewer colorectal adenomas and CRCs, but they also have more right-sided lesions, which are more difficult to detect with tests for faecal blood since they create less blood in faeces. Thus, other strategies may have to be developed for women in order for screening to have the same effect. It is essential to introduce colorectal cancer screening in all countries together with other clinical pieces of advice such as information on smoking, obesity and exercise in order to reduce one of the most dangerous cancers.

Overcoming the barriers to dissemination and implementation of quality measures for gastrointestinal endoscopy: European Society of Gastrointestinal Endoscopy (ESGE) and United European Gastroenterology (UEG) position statement

The European Society of Gastrointestinal Endoscopy (ESGE) has developed performance measures and established a framework for quality assessment for gastrointestinal endoscopy in Europe. Most national societies actively undertake initiatives to implement and explicitly endorse these quality indicators. Given this, the ESGE proposes that, at a national level, strong leadership should exist to disseminate and implement quality parameters. Thus, understanding the potential barriers that may vary locally is of paramount importance. The ESGE suggests that each national society should prioritise quality and standards of care in gastrointestinal endoscopy in their activities and should survey/understand which measures area local priority to their members and make measuring quality intrinsic to daily endoscopy practice.

Overcoming the barriers to dissemination and implementation of quality measures for gastrointestinal endoscopy: European Society of Gastrointestinal Endoscopy (ESGE) and United European Gastroenterology (UEG) position statement

The European Society of Gastrointestinal Endoscopy (ESGE) has developed performance measures and established a framework for quality assessment for gastrointestinal endoscopy in Europe. Most national societies actively undertake initiatives to implement and explicitly endorse these quality indicators. Given this, ESGE proposes that, at a national level, strong leadership should exist to disseminate and implement quality parameters. Thus, understanding the potential barriers that may vary locally is of paramount importance. ESGE suggests that each national society should prioritize quality and standards of care in gastrointestinal endoscopy in their activities and should survey/understand which measures are a local priority to their members and make measuring quality intrinsic to daily endoscopy practice.

Use of a GP-endorsed non-participant reminder letter to promote uptake of bowel scope screening: A randomised controlled trial in a hard-to-reach population

Previous research suggests that sending non-participants a reminder letter, 1 year after their initial invitation, can improve coverage for bowel scope screening (BSS), also known as flexible sigmoidoscopy screening. We hypothesised that adding a general practitioner's (GPs) endorsement to the reminder letter could improve coverage even further. We conducted a randomised controlled trial in North West London, UK. Participants were screening-eligible men and women who had not responded to their initial BSS invitation at least 12 months prior to the trial period. Eligible adults were randomised in a 1:1 ratio to receive either a GP-endorsed reminder letter, or a standard reminder letter from June to August 2019. Logistic regression models were used to test the effect of the GP endorsement on attendance at BSS, adjusting for sex, clinical commissioning group, and local area socioeconomic deprivation. In total, 1200 participants were enrolled into the study and randomised to either the control (n = 600) or the intervention (n = 600) group. Those who received the GP-endorsed reminder letter were only slightly more likely to attend BSS than those who received the standard reminder letter (4% vs. 3%); this difference was not statistically significant (Adjusted OR = 1.30; 95% CI: 0.69, 2.43). Adding a GP-endorsement to the annual reminder letter did not have an effect on attendance at BSS. One possible explanation for this is that the endorsement used was not personalised enough. Future research should examine stronger GP-endorsements or other methods to promote uptake.

The future of cancer screening after COVID-19 may be at home

LAY SUMMARY

During the coronavirus disease 2019 (COVID-19) pandemic, cancer screening decreased precipitously; home screening for colorectal cancer diminished less than that for colonoscopy and breast and cervical cancer screening. The authors have highlighted approaches for home cancer screening in addition to telemedicine.

Cost-effectiveness analysis of alternative colon cancer screening strategies in the context of the French national screening program

BACKGROUND

A nationwide colorectal cancer (CRC) screening program was set up in France from 2009 for average-risk, asymptomatic people aged 50-74 years based on an immunochemical fecal occult blood test [faecal immunochemical test (FIT)] every 2 years, followed by colonoscopy if positive. The European standard recommends a participation rate of 45% for the program to be cost-effective, yet the latest published rate in France was 34%. The objective of this study was to compare the cost effectiveness of screening alternatives taking real-world participation rates into account.

METHODS

Eight screening strategies were compared, based either on a screening test (Guaiac or FIT testing, blood-based, stool DNA, computed tomography colonography, colon capsules, and sigmoidoscopy) followed by full colonoscopy if positive or direct colonoscopy. A microsimulation model was used to estimate the cost effectiveness associated with each strategy.

RESULTS

Compared with no screening, FIT was associated with a 14.0 quality-adjusted life year (QALY) increase of €50,520 per 1000 individuals, giving an incremental cost-effectiveness ratio (ICER) of €3600/QALY. Only stool DNA and blood-based testing were associated with a QALY increase compared with FIT, with stool DNA weakly dominated by blood-based testing, and the latter associated with an ICER of €154,600/QALY compared with FIT. All other strategies were dominated by FIT.

CONCLUSION

FIT every 2 years appears to be the most cost-effective CRC screening strategy when taking into account a real-world participation rate of 34%.

“Your Finger or Mine?”—Patient Preferences in the Collection of Fecal Occult Blood Testing in the Emergency Department

Introduction

There are a number of presenting Emergency Department complaints that may necessitate the testing of stool for the presence of blood. A provider-performed digital rectal examination is frequently performed solely for the collection of stool for a fecal occult blood testing (FOBT). With increased emphasis on patient autonomy and shared decision-making, it is appropriate to consider patient preferences with regard to who performs the invasive collection of stool. Our objective was to determine patient preference in regard to provider versus self-collection of stool sample for use in FOBT and identify patient demographics associated with those more likely to self-collect. Finally, we examined specimen adequacy and patient satisfaction by open-ended comment.

Materials and Methods

We conducted a 1-year, prospective, non-randomized, observational trial with a convenience sample of 100 patients. After enrollment, study participants were offered the choice of self-collection versus provider collection. Stool collection proceeded according to participant preference. Simple descriptive statistics were used to analyze the primary outcome. The secondary proportional univariate outcomes were evaluated with chi-square testing (alpha level—0.05). We used a multivariable logistic regression model to evaluate the association of independent variables with the likelihood to perform self-collection.

Results

A total of 100 patients were enrolled over 1 year, with 51% choosing to collect their own sample. Younger age was the only statistically significant predictor for self-collection (p &lt; 0.001); furthermore, for every year of increasing age, patients were 3% less likely to choose self-collection. All self-collected samples were adequate for testing. In univariate analyses, patients younger than 35 were more likely to perform self-collection (66%) compared with those over 35 (36%). Those over 64 self-collected only 24% of the time. Neither sex nor race were associated with collection method preference.

Conclusions

When offered the choice between self-directed or provider-performed stool sample collection, more than half of participants chose to obtain their own sample; furthermore, age was the only statistically significant predictor of preference for collection method. All patients who self-collected were able to provide an adequate sample. Our evidence suggests the offer of FOBT self-collection is a feasible method to enhance patient autonomy and improve therapeutic alliances.

Long-term colorectal cancer incidence after adenoma removal and the effects of surveillance on incidence: a multicentre, retrospective, cohort study

OBJECTIVE

Postpolypectomy colonoscopy surveillance aims to prevent colorectal cancer (CRC). The 2002 UK surveillance guidelines define low-risk, intermediate-risk and high-risk groups, recommending different strategies for each. Evidence supporting the guidelines is limited. We examined CRC incidence and effects of surveillance on incidence among each risk group.

DESIGN

Retrospective study of 33 011 patients who underwent colonoscopy with adenoma removal at 17 UK hospitals, mostly (87%) from 2000 to 2010. Patients were followed up through 2016. Cox regression with time-varying covariates was used to estimate effects of surveillance on CRC incidence adjusted for patient, procedural and polyp characteristics. Standardised incidence ratios (SIRs) compared incidence with that in the general population.

RESULTS

After exclusions, 28 972 patients were available for analysis; 14 401 (50%) were classed as low-risk, 11 852 (41%) as intermediate-risk and 2719 (9%) as high-risk. Median follow-up was 9.3 years. In the low-risk, intermediate-risk and high-risk groups, CRC incidence per 100 000 person-years was 140 (95% CI 122 to 162), 221 (195 to 251) and 366 (295 to 453), respectively. CRC incidence was 40%-50% lower with a single surveillance visit than with none: hazard ratios (HRs) were 0.56 (95% CI 0.39 to 0.80), 0.59 (0.43 to 0.81) and 0.49 (0.29 to 0.82) in the low-risk, intermediate-risk and high-risk groups, respectively. Compared with the general population, CRC incidence without surveillance was similar among low-risk (SIR 0.86, 95% CI 0.73 to 1.02) and intermediate-risk (1.16, 0.97 to 1.37) patients, but higher among high-risk patients (1.91, 1.39 to 2.56).

CONCLUSION

Postpolypectomy surveillance reduces CRC risk. However, even without surveillance, CRC risk in some low-risk and intermediate-risk patients is no higher than in the general population. These patients could be managed by screening rather than surveillance.

A Fragile Balance: The Important Role of the Intestinal Microbiota in the Prevention and Management of Colorectal Cancer

BACKGROUND

Colorectal cancer is the second leading cause of cancer-related death worldwide. In recent years, researchers have focussed on the role of the intestinal microbiota in both the prevention and the treatment of colorectal cancer.

SUMMARY

The evidence in the literature supports that there is a fragile balance between different species of bacteria in the human gut. A disturbance of this balance towards increased levels of the bacteria Fusobacterium nucleatum and Bacteroides fragilis is associated with an increased risk of colorectal cancer. The mechanisms involved include the release of toxins which activate inflammation and the regulation of specific miRNAs (with an increase in the expression of oncogenic miRNAs and a decrease in the expression of tumour suppressor miRNAs), thereby increasing cell proliferation and leading to tumorigenesis. On the other hand, Lactobacillus and Bifidobacterium have a protective effect against the development of colorectal cancer through mechanisms that involve an increase in the levels of anticarcinogenic metabolites such as butyrate and a decrease in the activity of proinflammatory pathways. Even though preliminary studies support that the use of probiotics in the prevention and management of colorectal cancer is promising, more research is needed in this field. Key Message: The association between the intestinal microbiota, diet and colorectal cancer remains an active area of research with expected future applications in the use of probiotics for the prevention and management of this significant disease.

Non-Invasive Colorectal Cancer Screening: An Overview

Background

Colorectal cancer (CRC) follows a protracted stepwise progression, from benign adenomas to malignant adenocarcinomas. If detected early, 90% of deaths are preventable. However, CRC is asymptomatic in its early-stage and arises sporadically within the population. Therefore, CRC screening is a public health priority.

Summary

Faecal immunochemical test (FIT) is gradually replacing guaiac faecal occult blood test and is now the most commonly used screening tool for CRC screening program globally. However, FIT is still limited by the haemoglobin degradation and the intermittent bleeding patterns, so that one in four CRC cases are still diagnosed in a late stage, leading to poor prognosis. A multi-target stool DNA test (Cologuard, a combination of NDRG4 and BMP3 DNA methylation, KRAS mutations, and haemoglobin) and a plasma SEPT9 DNA methylation test (Epi proColon) are non-invasive tools also approved by the US FDA, but those screening approaches are not cost-effective, and the detection accuracies remain unsatisfactory. In addition to the approved tests, faecal-/blood-based microRNA and CRC-related gut microbiome screening markers are under development, with work ongoing to find the best combination of molecular biomarkers which maximise the screening sensitivity and specificity.

Key Message

Maximising the detection accuracy with a cost-effective approach for non-invasive CRC screening is urgently needed to further reduce the incidence of CRC and associated mortality rates.

Refinement and validation of the IDIOM score for predicting the risk of gastrointestinal cancer in iron deficiency anaemia

OBJECTIVE

To refine and validate a model for predicting the risk of gastrointestinal (GI) cancer in iron deficiency anaemia (IDA) and to develop an app to facilitate use in clinical practice.

DESIGN

Three elements: (1) analysis of a dataset of 2390 cases of IDA to validate the predictive value of age, sex, blood haemoglobin concentration (Hb), mean cell volume (MCV) and iron studies on the probability of underlying GI cancer; (2) a pilot study of the benefit of adding faecal immunochemical testing (FIT) into the model; and (3) development of an app based on the model.

RESULTS

Age, sex and Hb were all strong, independent predictors of the risk of GI cancer, with ORs (95% CI) of 1.05 per year (1.03 to 1.07, p<0.00001), 2.86 for men (2.03 to 4.06, p<0.00001) and 1.03 for each g/L reduction in Hb (1.01 to 1.04, p<0.0001) respectively. An association with MCV was also revealed, with an OR of 1.03 for each fl reduction (1.01 to 1.05, p<0.02). The model was confirmed to be robust by an internal validation exercise. In the pilot study of high-risk cases, FIT was also predictive of GI cancer (OR 6.6, 95% CI 1.6 to 51.8), but the sensitivity was low at 23.5% (95% CI 6.8% to 49.9%). An app based on the model was developed.

CONCLUSION

This predictive model may help rationalise the use of investigational resources in IDA, by fast-tracking high-risk cases and, with appropriate safeguards, avoiding invasive investigation altogether in those at ultra-low predicted risk.

Screening for atrial fibrillation: a call for evidence

Atrial fibrillation (AF) is the most common cardiac arrhythmia and prevalence is predicted to double over the next 30 years due to changing demographics and the rise in prevalence of risk factors such as hypertension and diabetes. Atrial fibrillation is associated with a five-fold increased stroke risk, but anticoagulation in eligible patients can reduce this risk by around 65%. Many people with AF currently go undetected and therefore untreated, either because they are asymptomatic or because they have paroxysmal AF. Screening has been suggested as one approach to increase AF detection rates and reduce the incidence of ischaemic stroke by earlier initiation of anticoagulation therapy. However, international taskforces currently recommend against screening, citing the cost implications and uncertainty over the benefits of a systematic screening programme compared to usual care. A number of large randomized controlled trials have commenced to determine the cost-effectiveness and clinical benefit of screening using a range of devices and across different populations. The recent AppleWatch study demonstrates how advances in technology are providing the public with self-screening devices that are increasingly affordable and accessible. Health care professionals should be aware of the implications of these emerging data for diagnostic pathways and treatment. This review provides an overview of the gaps in the current evidence and a summary of the arguments for and against screening.

Personalized Indicator Thrombocytosis Shows Connection to Staging and Indicates Shorter Survival in Colorectal Cancer Patients with or without Type 2 Diabetes

Background: Pre- and postoperative thrombocytosis was reported to have significant effect on patient survival. However, the definition of thrombocytosis throughout the literature is not unified. Methods: A retrospective longitudinal observational study has been conducted with the inclusion of 150 colorectal cancer (CRC) patients and 100 control subjects. A new measure of platelet changes at an individual level, named personalized indicator thrombocytosis (PIT) was defined, including 4 anemia adjusted variants. Results: In concordance with the literature, PIT values of control subjects showed a slow decrease in platelet counts, while PIT values of CRC patients were significantly higher (p < 0.0001). More advanced staging (p < 0.0001) and both local (p ≤ 0.0094) and distant (p ≤ 0.0440) metastasis are associated with higher PIT values. Higher PIT values suggested shorter survival times (p < 0.0001). Compared to conventional, a PIT-based definition resulted in approximately 3-times more patients with thrombocytosis. 28% and 77% of the deceased patients had conventional- and PIT-based thrombocytosis, respectively. Conclusions: Compared to conventional thrombocytosis, as an individual metric, PIT values may indicate the condition of patients more precisely. Possible future applications of PIT may include its usage in therapy decision and early cancer detection; therefore, further investigations are recommended.

The Role of Self-Determination in Changing Physical Activity Behavior in People Diagnosed With Bowel Polyps: A Pilot Randomized Controlled Trial

This nonblinded randomized controlled trial investigated the efficacy of a physical activity (PA) intervention underpinned by self-determination theory. Participants (N = 31, mean age 69 years [SD = 4.9]) diagnosed with bowel polyps were randomized to an active lifestyle program (ALP; n = 17) or standard care (n = 14). ALP received supervised exercise and counseling for 6 months. Both groups were followed up at 12 months. Outcomes were change in PA and behavioral regulation. Data were analyzed with intention to treat. At 6 months, differences were observed for behavioral regulation in favor of ALP (p < .05). PA differences were significant for leisure, walking, and vigorous in favor of ALP (p < .05). The self-determination theory can be an effective strategy for promoting PA behavior change in this population, but a larger trial is needed to further explore the utility of the self-determination theory in this context.

Circulating Extracellular Vesicle MicroRNA as Diagnostic Biomarkers in Early Colorectal Cancer-A Review

Colorectal cancer (CRC) is one of the most common malignancies in the developed world, with global deaths expected to double in the next decade. Disease stage at diagnosis is the single greatest prognostic indicator for long-term survival. Unfortunately, early stage CRC is often asymptomatic and diagnosis frequently occurs at an advanced stage, where long-term survival can be as low as 14%. Circulating microRNAs encapsulated in extracellular vesicles (EVs) have recently come to prominence as novel diagnostic markers for cancer. EV-miRNAs are dysregulated in the circulation of CRC patients compared to healthy controls, and several specific miRNA candidates have been posited as diagnostic markers, including miR-21, miR-23a, miR-1246, and miR-92a. This review outlines the current landscape of EV-miRNAs as potential diagnostic markers for CRC, with a specific focus on those able to detect early stage disease.

Increasing colorectal cancer incidence in individuals aged < 50 years-a population-based study

PURPOSE

Data on the incidence of colorectal cancer (CRC) is conflicting, and it is unknown if the incidence is constant, declining, or increasing. Proximal colon cancer is considered to be more common among older individuals, but recent data have shown that rectal cancer and distal colon cancer have been increasing in the younger population. The aim of this study was to determine the trends regarding CRC incidence and tumour location in Sweden.

METHODS

CRC statistics from the National Board of Health and Welfare 1995-2015 were used. CRC incidence rates by age group (< 50 years, 50-79 years, ≥ 80 years), sex, and tumour localisation (proximal colon, distal colon, or rectum) were calculated and analysed using Poisson regression.

RESULTS

The age-standardised incidence of CRC increased in Sweden during the study period. This increase was significant (P < 0.0001) for colon cancer during the study period for all age groups regardless of tumour localisation. The greatest increase (27-52% per decade) in the colon cancer incidence rate was seen among men and women < 50 years of age. The incidence rate for rectal cancer increased for men < 50 years (P < 0.0001), decreased for both men and women aged ≥ 80 years (P < 0.005), and did not change for the remaining groups.

CONCLUSIONS

The CRC incidence in Sweden, in particular colon cancer, is increasing regardless of tumour localisation for individuals < 50 years of age. This paper supports the implementation of population-based colorectal cancer screening. A diagnostic workup should be performed in symptomatic individuals < 50 years of age.

Meeting report from the joint IARC-NCI international cancer seminar series: a focus on colorectal cancer

Despite significant progress in our understanding of the etiology, biology and genetics of colorectal cancer, as well as important clinical advances, it remains the third most frequently diagnosed cancer worldwide and is the second leading cause of cancer death. Based on demographic projections, the global burden of colorectal cancer would be expected to rise by 72% from 1.8 million new cases in 2018 to over 3 million in 2040 with substantial increases anticipated in low- and middle-income countries. In this meeting report, we summarize the content of a joint workshop led by the National Cancer Institute and the International Agency for Research on Cancer, which was held to summarize the important achievements that have been made in our understanding of colorectal cancer etiology, genetics, early detection and treatment and to identify key research questions that remain to be addressed.

Improving diagnosis, prognosis and prediction by using biomarkers in CRC patients (Review)

Colorectal cancer (CRC) is among the most common cancers. In fact, it is placed in the third place among the most diagnosed cancer in men, after lung and prostate cancer, and in the second one for the most diagnosed cancer in women, following breast cancer. Moreover, its high mortality rates classifies it among the leading causes of cancer‑related death worldwide. Thus, in order to help clinicians to optimize their practice, it is crucial to introduce more effective tools that will improve not only early diagnosis, but also prediction of the most likely progression of the disease and response to chemotherapy. In that way, they will be able to decrease both morbidity and mortality of their patients. In accordance with that, colon cancer research has described numerous biomarkers for diagnostic, prognostic and predictive purposes that either alone or as part of a panel would help improve patient's clinical management. This review aims to describe the most accepted biomarkers among those proposed for use in CRC divided based on the clinical specimen that is examined (tissue, faeces or blood) along with their restrictions. Lastly, new insight in CRC monitoring will be discussed presenting promising emerging biomarkers (telomerase activity, telomere length and micronuclei frequency).