Comparison of Hemoccult, Magstream and OC-Sensor Faecal Occult Blood Tests in Colorectal Cancer Screening

University Hospital, Caen19,797 enrolled

Overview

Colorectal cancer screening by faecal occult blood test (FOBT) is a high public health priority. The interest of guaiac tests (G-FOBT) is limited by their poor sensitivity, while the superiority of I-FOBT in comparison with G-FOBT is now established. Nevertheless automated quantitative I-FOBTs have not been compared, and the optimal number of samples and threshold is not yet fixed. The aim of this study is to compare the performances of the 2 more well-known I-FOBTs with automated analyzers (magstream by Fujirebio, and OC Sensor by Eiken) for different positivity thresholds and numbers of samples in general average risk population. Patients will performed a two samples Magstream, a two samples OC Sensor and Hemoccult II. In case of a positive test, a colonoscopy will be performed. Sensitivity and specificity for detection of cancer and advanced neoplasias will be compared between tests using ratio of sensitivities (RSN) and ratio of false positives (RFP) according to number of samples and positivity threshold.

Study Type

INTERVENTIONAL

Allocation

Purpose

SCREENING

Masking

DOUBLE

Enrollment

19,797

Conditions

Colorectal Cancer

Interventions

Eligibility

Sex: ALLMin age: 50 YearsMax age: 74 Years

Medical Language ↔ Plain English

Inclusion Criteria: * 50 to 74 years * Informed consent signed Exclusion Criteria: * Recent digestive symptoms * Complete colonoscopy less than 5 years ago * Personal history of colorectal cancer or colorectal adenoma or colonic disease requiring regular colonoscopy surveillance * Familial history of colorectal cancer in a first degree next of kin before 65 years, or two cases in first degree next of kin. * Severe extra-intestinal disease * Screening ill-timed (ex. depression)

Outcomes

Primary Outcomes

Ratio of sensitivities (RSN) for detection of advanced neoplasias

Advanced neoplasias included invasive cancers and high-risk adenomas (larger than 1 cm or with high grade dysplasia). RSN is the ratio of the true positives of two tests. True positives for one test are patients positive for the test, with targeted lesion (here advanced neoplasias). RSN will be calculed between immunochemical tests, and for each immunochemical test in reference to gaiac test.

Time frame: Up to 6 months after faecal occult blood test (FOBT) (At the time of colonoscopy)

Secondary Outcomes

Ratio of False Positives (RFP) for detection of invasive cancers

RFP is related to specificity. False positives of one test are patients with a positive test but without targeted lesions (here invasive cancers). RFP will be calculed between immunochemical tests, and for each immunochemical test in reference to gaiac test.