Search results for "Colorectal Neoplasms."
showing 10 items of 431 documents
Comparison between a guaiac and three immunochemical faecal occult blood tests in screening for colorectal cancer
2012
Abstract Background The aim of this study was to compare the performance of the guaiac-based faecal occult blood test (G-FOBT), with that of three immunochemical faecal occult blood tests (I-FOBT) which allow automatic interpretation. Patients and methods Under the French organised screening programme, 85,149 average-risk individuals aged 50–74 participating in the third screening round, performed both the G-FOBT (Hemoccult-II test) and one of the I-FOBTs: FOB-Gold, Magstream and OC-Sensor. Results Given the chosen threshold, the positivity ratio between the different I-FOBTs and the G-FOBT was 2.4 for FOB-Gold, 2.0 for Magstream and 2.2 for OC-Sensor (P = 0.17). The three I-FOBTs were supe…
Immunochemical faecal occult blood tests are superior to guaiac-based tests for the detection of colorectal neoplasms
2008
The aim of this study was to compare the performance of a guaiac-based faecal occult blood test (G-FOBT) with that of an immunochemical faecal occult blood test (I-FOBT). A total of 17,215 average risk individuals aged 50 to 74 enrolled in a population-based organised screening programme and performed a 3-day G-FOBT and a 2-day I-FOBT simultaneously. Among participants, 3.1% were found positive for the G-FOBT and 6.9% for the I-FOBT (p<10(-4)). Among the 1205 participants who tested positive and underwent a colonoscopy, the number of detected cancers and advanced adenomas was respectively 2.6 times higher and 3.5 times higher with the I-FOBT than with the G-FOBT. The positive predictive val…
Synthetic indicator of the impact of colorectal cancer screening programmes on incidence rates
2020
ObjectiveThe impact of a screening programme on colorectal cancer (CRC) incidence in its target population depends on several variables, including coverage with invitations, participation rate, positivity rate of the screening test, compliance with an invitation to second-level assessment and endoscopists’ sensitivity. We propose a synthetic indicator that may account for all the variables influencing the potential impact of a screening programme on CRC incidence.DesignWe defined the ‘rate of advanced adenoma on the target population’ (AA-TAP) as the rate of patients who received a diagnosis of advanced adenoma within a screening programme, divided by the programme target population. We com…
Three-dimensional analysis of tumour vascular corrosion casts using stereoimaging and micro-computed tomography
2009
Objective: In order to perform effective translational research for cancer therapy, we need to employ preclinical models which reflect the clinical situation. The purpose of this study was to quantitatively compare the vascular architecture of human colorectal cancer and experimental tumour models to determine the suitability of animal models for vascular studies and antivascular therapy.Methods: In this study we investigated the three-dimensional properties of colonic tumour vasculature in both human clinical tissues (normal mucosa control [n = 20], carcinoma [n = 20] and adenoma In = 61) and murine colorectal xenografts (LS147T [n = 6] and SW1222 [n = 6]). Scanning Electron Microscope Ste…
The learning curve, accuracy, and interobserver agreement of endoscope-based confocal laser endomicroscopy for the differentiation of colorectal lesi…
2012
Background: The endoscope-based confocal laser endomicroscopy (eCLE) system allows in vivo imaging of colorectal epithelium. Little is known about the learning curve for accurate interpretation of confocal images acquired with eCLE. Objective: To determine the learning curve of eCLE, its diagnostic accuracy, and the intra- and interobserver agreement for the differentiation of colorectal lesions. Design: Post hoc assessment of selected eCLE images. Setting: Academic centers. Patients: This study involved colonoscopic images from 47 patients. Main Outcome Measurements: Learning curve of eCLE, accuracy, and intraobserver and interobserver agreement. Methods: Three endoscopists received a shor…
Colonoscopy and reduction of colorectal cancer risk by molecular tumor subtypes: a population-based case-control study
2020
AbstractObjectiveIn previous studies, the protective effect of colonoscopy was generally stronger for distal than for proximal colorectal cancer (CRC). This study aimed to investigate whether the association of colonoscopy and CRC risk varies according to major molecular pathological features and pathways of CRC.DesignPopulation-based case-control study from Germany, including 2132 patients with a first diagnosis of CRC and information on major molecular tumor markers, and 2486 control participants without CRC. Detailed participant characteristics were collected by standardized questionnaires and information on previous colonoscopy was derived from medical records. Polytomous logistic regre…
Rural–urban differences in the long-term risk of colorectal cancer after adenoma removal: A population-based study
2013
Abstract Background We investigated the impact of municipality of residence on colonoscopic surveillance and colorectal cancer risk after adenoma resection in a French well-defined administrative area. Methods This registry-based study included all patients residing in Cote d’Or (n = 5769) first diagnosed with colorectal adenomas between January 1, 1990, and December 31, 1999. Information about colonoscopic surveillance and colorectal cancer incidence was collected until December 31, 2003. Results A rural place of residence reduced the probability of colonoscopic surveillance in men [HR = 0.89 (95%CI: 0.79–0.99), p = 0.041] and in patients without family history of colorectal cancer [HR = 0…
3D microvascular architecture of pre-cancerous lesions and invasive carcinomas of the colon.
2001
Despite the significance of tumour neoangiogenesis and the extensive knowledge on the molecular basis of blood vessel formation currently no quantitative data exist on the 3D microvascular architecture in human primary tumours and their precursor lesions. This prompted us to examine the 3D vascular network of normal colon mucosa, adenomas and invasive carcinomas by means of quantitative microvascular corrosion casting. Fresh hemicolectomy specimens from 20 patients undergoing cancer or polyposis coli surgery were used for corrosion casting, factor VIII and VEGF immunostaining. In addition, immunostaining was done on colorectal tissue from 33 patients with metastatic and non-metastatic carci…
Faecal immunochemical tests: A valuable tool for colorectal cancer screening
2012
Colorectal cancer is a major health problem in industrialized ountries and fulfils the conditions required to justifymass screenng of the general population. Population-based controlled studies erformed in Europe have shown that guaiac faecal occult blood esting (G-FOBT) followed by colonoscopy to detect the cause of leeding can reduce colorectal cancer mortality [1]. Nearly all pubished studies evaluated the Hemoccult II (Beckman Coulter Inc., ea, USA) faecal occult blood test. Screening for colorectal caner using FOBT has, therefore, been included in the European Code gainst Cancer and has been endorsed by the European Commision [2]. Despite its high specificity, Hemoccult has been critic…
Comparison of the yield from two faecal immunochemical tests at identical cutoff concentrations – a randomized trial in Latvia
2016
OBJECTIVE We have compared the performance of two faecal immunochemical tests (FIT) in an average-risk population. MATERIALS AND METHODS Altogether, 10 000 individuals aged 50-74 were selected randomly from the population of Latvia in 2011 and assigned randomly either to OC-Sensor or to FOB Gold single-time testing. Positivity of the test, frequency of colonic lesions, number needed to screen (NNscreen) and scope for the detection of an advanced neoplasm (cancer and advanced adenoma) were compared between the tests using the same cutoff concentrations in µg/g faeces. Confidence intervals (CIs) at 95% were calculated. RESULTS Positivity with the cutoff set at 10 µg/g faeces was 12.8% (95% CI…