Population screening for colorectal cancer by flexible sigmoidoscopy or CT colonography: Study protocol for a multicenter randomized trial

BACKGROUND: Colorectal cancer (CRC) is the second most prevalent type of cancer in Europe. A single flexible sigmoidoscopy (FS) screening at around the age of 60 years prevents about one-third of CRC cases. However, FS screens only the distal colon, and thus mortality from proximal CRC is unaffected. Computed tomography colonography (CTC) is a highly accurate examination that allows assessment of the entire colon. However, the benefit of CTC testing as a CRC screening test is uncertain. We designed a randomized trial to compare participation rate, detection rates, and costs between CTC (with computer-aided detection) and FS as primary tests for population-based screening. METHODS/DESIGN: An invitation letter to participate in a randomized screening trial comparing CTC versus FS will be mailed to a sample of 20,000 people aged 58 or 60 years, living in the Piedmont region and the Verona district of Italy. Individuals with a history of CRC, adenomas, inflammatory bowel disease, or recent colonoscopy, or with two first-degree relatives with CRC will be excluded from the study by their general practitioners. Individuals responding positively to the invitation letter will be then randomized to the intervention group (CTC) or control group (FS), and scheduled for the screening procedure. The primary outcome parameter of this part of the trial is the difference in advanced neoplasia detection between the two screening tests. Secondary outcomes are cost-effectiveness analysis, referral rates for colonoscopy induced by CTC versus FS, and the expected and perceived burden of the procedures. To compare participation rates for CTC versus FS, 2,000 additional eligible subjects will be randomly assigned to receive an invitation for screening with CTC or FS. In the CTC arm, non-responders will be offered fecal occult blood test (FOBT) as alternative screening test, while in the FS arm, non-responders will receive an invitation letter to undergo screening with either FOBT or CTC. Data on reasons for participation and non-participation will also be collected. DISCUSSION: This study will provide reliable information concerning benefits and risks of the adoption of CTC as a mass screening intervention in comparison with FS. The trial will also evaluate the role of computer-aided detection in a screening setting. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT0173960

MECPerf: An Application-Level Tool for Estimating the Network Performance in Edge Computing Environments

Edge computing is an emerging architecture in 5G networks where computing power is provided at the edge of the fixed network, to be as close as possible to the end users. Computation offloading, better communication latency, and reduction of traffic in the core network are just some of the possible benefits. However, the Quality of Experience (QoE) depends significantly on the network performance of the user device towards the edge server vs. cloud server, which is not known a priori and may generally change very fast, especially in heterogeneous, dense, and mobile deployments. Building on the emergence of standard interfaces for the installation and operation of thirdparty edge applications in a mobile network, such as the MultiAccess Edge Computing (MEC) under standardization at the European Telecommunications Standards Institute (ETSI), we propose MECPerf, a tool for user-driven network performance measurements. Bandwidth and latency on different network segments are measured and stored in a central repository, from where they can be analyzed, e.g., by application and service providers without access to the underlying network management services, for run-time resource optimization

Hospital factors and patient characteristics in the treatment of colorectal cancer: a population based study

BACKGROUND: The present study focuses on the analysis of social, clinical and hospital characteristics that can lead to disparities in the management and outcome of care. To that end, indicators of the quality of initial treatment delivered to newly-diagnosed colorectal cancer patients in a North-Western Region of Italy, were investigated using administrative data. METHODS: The cohort includes all incident colorectal cancer patients (N = 24,187) selected by a validated algorithm from the Piedmont Hospital Discharge Record system over an 8-year period (2000–2007). Three indicators of quality of care in this population-based cohort were evaluated: the proportion of preoperative radiotherapy (RT) and of abdominoperineal (AP) resection in rectal cancer patients, and the proportion of postoperative in-hospital mortality in colorectal cancer patients. RESULTS: Among rectal cancers, older patients were less likely to have preoperative RT, and more likely to receive an AP resection compared to younger patients. The probability of undergoing preoperative RT and AP resection was reduced in females compared to males (odds ratio (OR) 0.77, 95% confidence interval (CI) 0.64-0.93 and OR 0.78, 95%CI 0.69-0.89, respectively). However, there was a trend of increasing RT over time (p for trend <0.01). The probability of undergoing AP resection was increased in less-educated patients and in hospitals with a low caseload. A higher risk of postoperative in-hospital mortality was found among colorectal cancer patients who were older, male, (female versus male OR 0.71, 95%CI 0.60-0.84), unmarried (OR 1.32, 95%CI 1.09-1.59) or with unknown marital status. CONCLUSIONS: The study provides evidence of the importance of social, clinical and hospital characteristics on the equity and quality of care in a Southern European country with an open-access public health care system

Impact of colorectal cancer screening on cancer-specific mortality in Europe: A systematic review

Background: Populations differ with respect to their cancer risk and screening preferences, which may influence the performance of colorectal cancer (CRC) screening programs. This review aims to

Narrow-band Imaging for Detection of Neoplasia at Colonoscopy: a Meta-analysis of Data From Individual Patients in Randomized Controlled Trials

Background & Aims Adenoma detection rate (ADR) is an important quality assurance measure for colonoscopy. Some studies suggest that narrow band imaging (NBI) may be more effective at detection of adenomas than white-light endoscopy (WLE) when bowel preparation is optimal. We conducted a meta-analysis of data from individual patients in randomized controlled trials that compared the efficacy of NBI to WLE in detection of adenomas. Methods We searched MEDLINE, EMBASE, and Cochrane library databases, through April 2017, for randomized controlled trials that assessed detection of colon polyps by high-definition WLE vs NBI and from which data on individual patients was available. The primary outcome measure was ADR adjusted for bowel preparation quality. Multilevel regression models were used with patients nested within trials, and trial included as a random effect. Results We collected data from 11 trials, comprising 4491 patients and 6636 polyps detected. Adenomas were detected in 952/2251 (42.3%) participants examined by WLE vs 1011/2239 (45.2%) participants examined by NBI (unadjusted odds ratio [OR] for detection of adenoma by WLE vs NBI, 1.14; 95% CI, 1.01–1.29; P=.04). NBI outperformed WLE only when bowel preparation was best: adequate preparation OR, 1.07 (95% CI, 0.92–1.24; P=.38) vs best preparation OR, 1.30 (95% CI, 1.04–1.62; P=.02). Second-generation bright NBI had a better ADR than WLE (second-generation NBI OR, 1.28; 95% CI, 1.05–1.56; P=.02), whereas first-generation NBI did not. NBI detected more non-adenomatous polyps than WLE (OR, 1.24; 95% CI, 1.06–1.44; P=.008) and flat polyps than WLE (OR, 1.24; 95% CI, 1.02–1.51; P=.03). Conclusions In a meta-analysis of data from individual patients in randomized controlled trials, we found NBI to have a higher ADR than WLE, and that this effect is greater when bowel preparation is optimal

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

All-cause mortality versus cancer-specific mortality as outcome in cancer screening trials: A review and modeling study

Background: All-cause mortality has been suggested as an end-point in cancer screening trials in order to avoid biases in attributing the cause of death. The aim of this study was to investigate which sample size and follow-up is needed to find a significant reduction in all-cause mortality. Methods: A literature review was conducted to identify previous studies that modeled the effect of screening on all-cause mortality. Microsimulation modeling was used to simulate breast cancer, lung cancer, and colorectal cancer screening trials. Model outputs were: cancer-specific deaths, all-cause deaths, and life-years gained per year of follow-up. Results: There were large differences between the evaluated cancers. For lung cancer, when 40 000 high-risk people are randomized to each arm, a significant reduction in all-cause mortality could be expected between 11 and 13 years of follow-up. For breast cancer, a significant reduction could be found between 16 and 26 years of follow-up for a sample size of over 300 000 women in each arm. For colorectal cancer, 600 000 persons in each arm were required to be followed for 15-20 years. Our systematic literature review identified seven papers, which showed highly similar results to our estimates. Conclusion: Cancer screening trials are able to demonstrate a significant reduction in all-cause mortality due to screening, but require very large sample sizes. Depending on the cancer, 40 000-600 000 participants per arm are needed to demonstrate a significant reduction. The reduction in all-cause mortality can only be detected between specific years of follow-up, more limited than the timeframe to detect a reduction in cancer-specific mortality

Recommendations for a step-wise comparative approach to the evaluation of new screening tests for colorectal cancer

BACKGROUND: New screening tests for colorectal cancer continue to emerge, but the evidence needed to justify their adoption in screening programs remains uncertain.METHODS: A review of the literature and a consensus approach by experts was undertaken to provide practical guidance on how to compare new screening tests with proven screening tests.RESULTS: Findings and recommendations from the review included the following: Adoption of a new screening test requires evidence of effectiveness relative to a proven comparator test. Clinical accuracy supported by programmatic population evaluation in the screening context on an intention-to-screen basis, including acceptability, is essential. Cancer-specific mortality is not essential as an endpoint provided that the mortality benefit of the comparator has been demonstrated and that the biologic basis of detection is similar. Effectiveness of the guaiac-based fecal occult blood test provides the minimum standard to be achieved by a new test. A 4-phase evaluation is recommended. An initial retrospective evaluation in cancer cases and controls (Phase 1) is followed by a prospective evaluation of performance across the continuum of neoplastic lesions (Phase 2). Phase 3 follows the demonstration of adequate accuracy in these 2 prescreening phases and addresses programmatic outcomes at 1 screening round on an intention-to-screen basis. Phase 4 involves more comprehensive evaluation of ongoing screening over multiple rounds. Key information is provided from the following parameters: the test positivity rate in a screening population, the true-positive and false-positive rates, and the number needed to colonoscope to detect a target lesion.CONCLUSIONS: New screening tests can be evaluated efficiently by this stepwise comparative approach. Cancer 2016;122:826-39. © 2016 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society.</p