Targeting Chemoprevention of Colorectal Cancer to Those Who Are Likely to Respond

In the past four decades, chemoprevention of colorectal cancer (CRC) has been the subject of many epidemiologic and intervention trials of naturally occurring or pharmacologic agents. Recently, the positioning of cyclooxygenase 2 inhibitors as a viable option in this context was a major breakthrough; however, it was hampered by adverse cardiovascular events. This review questions whether chemopreventive measures for CRC are ready to be used in mass or individual applications, standing alone or in combination with other CRC-preventive measures. It also discusses steps that may be undertaken to explore this field further

Colon Capsule Endoscopy compared to Conventional Colonoscopy under routine screening conditions

Colonoscopy (CSPY) for colorectal cancer screening has several limitations. Colon Capsule Endoscopy (PillCam Colon, CCE) was compared to CSPY under routine screening conditions

Improving Colorectal Cancer Screening in Primary Care Practice: Innovative Strategies and Future Directions

Colorectal cancer (CRC) screening has been supported by strong research evidence and recommended in clinical practice guidelines for more than a decade. Yet screening rates in the United States remain low, especially relative to other preventable diseases such as breast and cervical cancer. To understand the reasons, the National Cancer Institute and Agency for Healthcare Research and Quality sponsored a review of CRC screening implementation in primary care and a program of research funded by these organizations. The evidence base for improving CRC screening supports the value of a New Model of Primary Care Delivery: 1. a team approach, in which responsibility for screening tasks is shared among other members of the practice, would help address physicians’ lack of time for preventive care; 2. information systems can identify eligible patients and remind them when screening is due; 3. involving patients in decisions about their own care may enhance screening participation; 4. monitoring practice performance, supported by information systems, can help target patients at increased risk because of family history or social disadvantage; 5. reimbursement for services outside the traditional provider—patient encounter, such as telephone and e-mail contacts, may foster enhanced screening delivery; 6. training opportunities in communication, cultural competence, and use of information technologies would improve provider competence in core elements of screening programs. Improvement in CRC screening rates largely depends on the efforts of primary care practices to implement effective systems and procedures for screening delivery. Active engagement and support of practices are essential for the enormous potential of CRC screening to be realized

Gender differences in colorectal cancer: implications for age at initiation of screening

There is some variation regarding age at initiation of screening for colorectal cancer (CRC) between countries, but the same age of initiation is generally recommended for women and men within countries, despite important gender differences in the epidemiology of CRC. We have explored whether, and to what extent, these differences would be relevant regarding age at initiation of CRC screening. Using population-based cancer registry data from the US and national mortality statistics from different countries, we looked at cumulative 10-year incidence and mortality of CRC reached among men at ages 50, 55, and 60, and found that women mainly reached equivalent levels when 4 to 8 years older. The gender differences were remarkably constant across populations and over time. These patterns suggest that gender differentiation of age at initiation may be worthwhile to utilise CRC-screening resources more efficiently

European guidelines for quality assurance in colorectal cancer screening and diagnosis: overview and introduction to the full supplement publication

Population-based screening for early detection and treatment of colorectal cancer (CRC) and precursor lesions, using evidence-based methods, can be effective in populations with a significant burden of the disease provided the services are of high quality. Multidisciplinary, evidence-based guidelines for quality assurance in CRC screening and diagnosis have been developed by experts in a project co-financed by the European Union. The 450-page guidelines were published in book format by the European Commission in 2010. They include 10 chapters and over 250 recommendations, individually graded according to the strength of the recommendation and the supporting evidence. Adoption of the recommendations can improve and maintain the quality and effectiveness of an entire screening process, including identification and invitation of the target population, diagnosis and management of the disease and appropriate surveillance in people with detected lesions. To make the principles, recommendations and standards in the guidelines known to a wider professional and scientific community and to facilitate their use in the scientific literature, the original content is presented in journal format in an open-access Supplement of Endoscopy. The editors have prepared the present overview to inform readers of the comprehensive scope and content of the guidelines.Fil: Arrossi, Silvina. Centro de Estudios de Estado y Sociedad; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: von Karsa, Lawrence. International Agency for Research on Cancer; FranciaFil: Patrick, J.. NHS Cancer Screening Programmes Sheffield; Reino Unido. University of Oxford; Reino UnidoFil: Segnan, N.. International Agency for Research on Cancer; Francia. AO Città della Salute e della Scienza di Torino; ItaliaFil: Atkin, W.. Imperial College London; Reino UnidoFil: Halloran, S.. University of Surrey; Reino UnidoFil: Saito, H.. National Cancer Centre; JapónFil: Sauvaget, C.. International Agency for Research on Cancer; FranciaFil: Scharpantgen, A.. Ministry of Health; LuxemburgoFil: Schmiegel, W.. Ruhr-Universität Bochum; AlemaniaFil: Senore, C.. AO Città della Salute e della Scienza di Torino; ItaliaFil: Siddiqi, M.. Cancer Foundation of India; IndiaFil: Sighoko, D.. University of Chicago; Estados Unidos. Formerly International Agency for Research on Cancer; FranciaFil: Smith, R.. American Cancer Society; Estados UnidosFil: Smith S.. University Hospitals Coventry & Warwickshire NHS Trust; Reino UnidoFil: Suchanek, S.. Charles University; República ChecaFil: Suonio, E.. International Agency for Research on Cancer; FranciaFil: Tong, W.. Chinese Academy of Sciences; República de ChinaFil: Törnberg, S.. Stockholm Gotland Regional Cancer Centre. Department of Cancer Screening; SueciaFil: Van Cutsem, E.. Katholikie Universiteit Leuven; BélgicaFil: Vignatelli, L.. Agenzia Sanitaria e Sociale Regionale; ItaliaFil: Villain, P.. University of Oxford; Reino UnidoFil: Voti, L.. Formerly International Agency for Research on Cancer; Francia. University of Miami; Estados UnidosFil: Watanabe, H.. Niigata University; JapónFil: Watson, J.. University of Oxford; Reino UnidoFil: Winawer, S.. Memorial Sloan–Kettering Cancer Center; Estados UnidosFil: Young, G.. Flinders University. Gastrointestinal Services; AustraliaFil: Zaksas, V.. State Patient Fund; LituaniaFil: Zappa, M.. Cancer Prevention and Research Institute; ItaliaFil: Valori, R.. NHS Endoscopy; Reino Unid

Tumour M2-PK as a stool marker for colorectal cancer: comparative analysis in a large sample of unselected older adults vs colorectal cancer patients

Stool testing based on tumour-derived markers might offer a promising approach for non-invasive colorectal cancer (CRC) screening. The aim of this study was to estimate the potential of a new test for faecal tumour M2-PK to discriminate patients with CRC from a large sample of unselected older adults. Faecal tumour M2-PK concentrations were determined in 65 CRC patients and in a population-based sample of 917 older adults (median age: 65 and 62 years, respectively). Sensitivity and specificity of the test were calculated at different cutoff values, and receiver-operating characteristic curves (ROC) were constructed to visualise the discriminatory power of the test. The median (interquartile range) faecal tumour M2-PK concentration was 8.6 U ml−1 (2.8–18.0) among CRC patients and <2 U ml−1 (<2–3.2; P<0.0001) in the population sample. At a cutoff value of 4 U ml−1, sensitivity (95% confidence interval) was 85% (65–96%) for colon cancer and 56% (41–74%) for rectum cancer. Specificity (95% confidence interval) was estimated to be 79% (76–81%). Given the comparatively high sensitivity of the tumour M2-PK stool test (especially for colon cancer) and its simple analysis, the potential use of the test for early detection of CRC merits further investigation. Possibilities to enhance specificity of the test should be explored

Number and Size Distribution of Colorectal Adenomas under the Multistage Clonal Expansion Model of Cancer

Colorectal cancer (CRC) is believed to arise from mutant stem cells in colonic crypts that undergo a well-characterized progression involving benign adenoma, the precursor to invasive carcinoma. Although a number of (epi)genetic events have been identified as drivers of this process, little is known about the dynamics involved in the stage-wise progression from the first appearance of an adenoma to its ultimate conversion to malignant cancer. By the time adenomas become endoscopically detectable (i.e., are in the range of 1–2 mm in diameter), adenomas are already comprised of hundreds of thousands of cells and may have been in existence for several years if not decades. Thus, a large fraction of adenomas may actually remain undetected during endoscopic screening and, at least in principle, could give rise to cancer before they are detected. It is therefore of importance to establish what fraction of adenomas is detectable, both as a function of when the colon is screened for neoplasia and as a function of the achievable detection limit. To this end, we have derived mathematical expressions for the detectable adenoma number and size distributions based on a recently developed stochastic model of CRC. Our results and illustrations using these expressions suggest (1) that screening efficacy is critically dependent on the detection threshold and implicit knowledge of the relevant stem cell fraction in adenomas, (2) that a large fraction of non-extinct adenomas remains likely undetected assuming plausible detection thresholds and cell division rates, and (3), under a realistic description of adenoma initiation, growth and progression to CRC, the empirical prevalence of adenomas is likely inflated with lesions that are not on the pathway to cancer

Colorectal cancer screening awareness among physicians in Greece

BACKGROUND: Data comparison between SEER and EUROCARE database provided evidence that colorectal cancer survival in USA is higher than in European countries. Since adjustment for stage at diagnosis markedly reduces the survival differences, a screening bias was hypothesized. Considering the important role of primary care in screening activities, the purpose of the study was to investigate the colorectal cancer screening awareness among Hellenic physicians. METHODS: 211 primary care physicians were surveyed by mean of a self-reported prescription-habits questionnaire. Both physicians' colorectal cancer screening behaviors and colorectal cancer screening recommendations during usual check-up visits were analyzed. RESULTS: Only 50% of physicians were found to recommend screening for colorectal cancer during usual check-up visits, and only 25% prescribed cost-effective procedures. The percentage of physicians recommending stool occult blood test and sigmoidoscopy was 24% and 4% respectively. Only 48% and 23% of physicians recognized a cancer screening value for stool occult blood test and sigmoidoscopy. Colorectal screening recommendations were statistically lower among physicians aged 30 or less (p = 0.012). No differences were found when gender, level and type of specialization were analyzed, even though specialists in general practice showed a trend for better prescription (p = 0.054). CONCLUSION: Contemporary recommendations for colorectal cancer screening are not followed by implementation in primary care setting. Education on presymptomatic control and screening practice monitoring are required if primary care is to make a major impact on colorectal cancer mortality