Colorectal cancer mass-screening: Estimation of faecal occult blood test sensitivity, taking into account cancer mean sojourn time

Comparison of a guaiac and an immunochemical faecal occult blood test for the detection of colonic lesions according to lesion type and location

“…Our results are consistent with previous studies, suggesting that the sensitivity of Haemoccult G-FOBT is stable whatever the location (Launoy et al, 1997) and that the sensitivity of Magstream I-FOBT is higher for rectal þ distal colonic tumours than for proximal colonic tumours (Morikawa et al, 2005). A nonsignificant increase in the sensitivity of the OC-sensor I-FOBT was also observed for the detection of invasive cancers of the rectum versus the colon .…”

“…Moreover, the comparison (both globally and according to location) of sensitivity for the detection of invasive cancers and high-risk adenomas benefited from the paired comparison of the tests used in this study. Indeed, the sensitivity for the detection of invasive cancers for each test has been studied essentially using (with the exception of the Morikawa study) data from registries (detection or incidence methods (Day, 1985)) (Launoy et al, 1997;Morikawa et al, 2005;Castiglione et al, 2007). However, these methods cannot be used to detect high-risk adenomas because of their small probability of becoming symptomatic within 2 years, unless they evolve towards invasive cancer.…”

Estimation of screening test (Hemoccult®) sensitivity in colorectal cancer mass screening

“…It is significantly smaller in females than in males in the Nottingham study and does not increase with time. The Calvados results (Launoy et al, 1997) are qualitatively similar to those of Nottingham. It is difficult to understand these discrepancies but the random fluctuations of the number of cases are too large to permit a more satisfactory analysis.…”

“…The data of the present intervention led to results of the same order of magnitude but slightly smaller (43.4%). In contrast with this broad agreement on efficacy there is a wide range in the various sensitivity estimates of the test (GyrdHansen et al, 1997;Launoy et al, 1997;Moss et al, 1999) ranging from 22% to 90% (Moss et al, 1999). Even if we restrict the review to population-based study we obtain a large range of estimates (34% to 75%).…”

Sensitivity of latex agglutination faecal occult blood test in the Florence District population-based colorectal cancer screening programme

“…Randomised trials demonstrating FOBT screening effectiveness used a 3-day guaiac-based test (G-FOBT), a chemical test based on haemoglobin peroxidase-like activity whose accuracy is affected by dietary factors such as the presence of nonhuman haemoglobin and peroxidases in vegetables, or by certain drugs, particularly NSAIDs. Sensitivity of G-FOBT for CRC has been reported to be as low as 43-66%, based on a 2-year screening interval (Jensen et al, 1992;Launoy et al, 1997;Moss et al, 1999;Jouve et al, 2001); attempts to increase sensitivity either by rehydration (Church et al, 1997) or by increased reagent concentration (Petrelli et al, 1994;Allison et al, 1996) were associated with unacceptable loss in specificity. Several studies have suggested that immunochemical FOBT (I-FOBT) is more sensitive and specific than G-FOBT Saito et al, 2000;Zappa et al, 2001; Levi et al, 2006;Guittet et al, 2007), requiring no dietary restrictions, and might substantially improve screening cost effectiveness Saito et al, 2000).…”