Cost-effectiveness analysis of two strategies for mass screening for colorectal cancer in France.

The implementation of colorectal cancer mass screening is a high public health priority in France, as in most other industrialised countries. Despite evidences that screening using guaiac fecal occult blood test may reduce colorectal cancer mortality, no European country has organised widespread mass screening with this test. The low sensitivity of this test constitutes its main limitation. Immunological tests, which provide higher sensitivity than the guaiac test, may constitute a satisfactory alternative. This study was carried out to compare the costs and the effectiveness of 20 years of biennial colorectal cancer (CRC) screening with an automated reading immunological test (Magstream) with those obtained with a guaiac stool test (Haemoccult). The model used to estimate the costs and effectiveness of successive biennial CRC screening campaigns was a transitional probabilistic model. The parameters used in this model concerning costs and CRC epidemiological data were calculated from results obtained in the screening program run in Calvados or from published results of foreign studies because of the lack of French studies. The use of Magstream for 20 years of biennial screening costs 59 euros more than Haemoccult per target individual, and should lead to a mean increase in individual life expectancy of 0.0198 years (i.e. about one week), which corresponds to an incremental cost-effectiveness ratio of 2980 euros per years of life saved. Our results suggest that using an immunological test could increase the effectiveness of CRC screening at a reasonable cost for society. Copyright 2003 John Wiley & Sons, Ltd.