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

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.