Comparison between a guaiac and three immunochemical faecal occult blood tests in screening for colorectal cancer

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 superior to the G-FOBT for colorectal cancer (CRC) detection. The ratios for detection rates were 1.6 (FOB-Gold), 1.7 (Magstream) and 2.1 (OC-Sensor) ( P  = 0.74). For non-invasive CRC they were, respectively, 2.5, 3.0 and 4.0 ( P  = 0.83) and for advanced adenomas 3.6, 3.1 and 4.0 ( P  = 0.39). Conclusions This study provides further evidence that I-FOBT is superior to G-FOBT. None of the three I-FOBTs studied appeared to be significantly better than the others.