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Faecal immunochemical tests: A valuable tool for colorectal cancer screening
Digestive and Liver Disease 44 (2012) 629–630
Contents lists available at SciVerse ScienceDirect
Digestive and Liver Disease journal homepage: www.elsevier.com/locate/dld
Editorial
Faecal immunochemical tests: A valuable tool for colorectal cancer screening Côme Lepage a,b,c,∗ , Samia Hamza a,b,c a
Burgundy Digestive Cancer Registry, INSERM U866, 21079 Dijon Cedex, France University of Burgundy, France c University Hospital of Dijon, France b
Colorectal cancer is a major health problem in industrialized countries and fulfils the conditions required to justify mass screening of the general population. Population-based controlled studies performed in Europe have shown that guaiac faecal occult blood testing (G-FOBT) followed by colonoscopy to detect the cause of bleeding can reduce colorectal cancer mortality [1]. Nearly all published studies evaluated the Hemoccult II (Beckman Coulter Inc., Bea, USA) faecal occult blood test. Screening for colorectal cancer using FOBT has, therefore, been included in the European Code against Cancer and has been endorsed by the European Commission [2]. Despite its high specificity, Hemoccult has been criticized for its fairly low sensitivity and because it reacts with non-human haeme in food. For these reasons, attention has been given to alternative screening strategies, in particular, immunochemical faecal occult blood testing (I-FOBT). Accurate interpretation of G-FOBTs is not easy and requires well established laboratories. The development of quantitative I-FOBTs and of automated systems for the interpretation of the screening test has increased interest in I-FOBTs, as they minimise human error in test processing and allow excellent quality control. One limit of I-FOBTs was that globin (the measured component of haemoglobin in these tests) was not stable in the buffer and was prone to denaturation. Manufacturers have now modified the buffer to increase globin stability. None of the quantitative I-FOBT appeared to be clearly better than the others [3]. Moreover improved standardisation is necessary so that the tests can be compared directly. To date, there are no internationally agreed standards. In the current issue of Digestive and Liver Disease, two separate studies provide comparisons of the performance of Hemoccult II with that of three different available I-FOBTs. The results are of interest in that they concern subjects attending subsequent screening rounds, while most studies have reported data concerning the prevalent round. Faivre at al. [4] have added to our understanding of colorectal cancer screening using I-FOBT. The study provides a direct comparison of the performance of Hemoccult II given with one of the two studied immunochemical quantitative tests OC-Sensor (Eiken,
∗ Corresponding author at: BP 87900, 21079 Dijon, France. Tel.: +33 3 80 29 37 50; fax: +33 3 80 29 37 22. E-mail address: [email protected] (C. Lepage).
Tokyo, Japan) and FOB-Gold (Sentinel, for Beckman Coulter Inc., Milan, Italy), used with one or two-day sampling at different cutoff values in a large population-based cohort. It is therefore a major study since it allows the indirect comparison of two I-FOBTs with the reference test (Hemoccult), and also provides results at varying level of test positivity. The authors concluded that 2-day sampling, with at least one positive test, at a cut-off value situated between 150 and 200 ng/mL for OC-Sensor and the corresponding values of 176 and 234 ng/mL for FOB-Gold would be an acceptable strategy in France. However, they also state that one-day testing using a lower cut-off than the one previously described can be an alternative. Two-day sampling improves sensitivity but increases costs. Guitet et al. [5] in the same issue, provided further evidence using a qualitative marketed I-FOBT Magstream (Fujirebio Inc., Tokyo, Japan) using either one- or two-day sampling. The crude results of the Magstream 1000 automat analyzer were then derived through an equation provided by the manufacturer in order to be able to vary the level of test positivity. The authors stated that using the crude result, this test worked, in the target population, as a quantitative test. As in the previous study, identical performances in terms of detection rate were found. This study nicely highlights that using one test there is a compromise between the mean intensity of bleeding and the extent of bleeding fluctuation. This study is of major interest because it underlines the fact that identical performances can be obtained with one or two faecal samples provided a different cut-off value is chosen (for instance 39 mg/mL with one sample and 63 mg/mL with two samples and at least one positive test). As discussed by the authors, parameters other than test performance and participation must also be taken into account: the ease of sample collection and test interpretation, the performance of automated analysers, the stability of test samples over time in particular depending on the ambient temperature, and costeffectiveness analyses. Currently, one sampling strategy with the OC-Sensor test is used with success in Italy (100 ng/mL) [6]. It is also proposed in the Netherlands with a threshold of 50–75 ng/mL. In this regards several medical-economic studies have been performed over the last two years [7], and they all concluded that immunological tests were an effective alternative to the Hemoccult test. They also argued in favour of taking a single sample.
1590-8658/$36.00 © 2012 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.dld.2012.05.015
630
C. Lepage, S. Hamza / Digestive and Liver Disease 44 (2012) 629–630
Several key points of the I-FOBT test must be taken into account. Whatever the conditions, immunoassay tests are superior to Hemoccult [8–11]. These studies nicely highlight the fact that they are better accepted. These tests will allow the doubling of the cancer detection rate and will increase the adenoma detection rate by 3–4 times. The French Health Minister announced that these tests will be used for the National campaign for colorectal cancer screening from 2013. Thanks to these performance data, we can surmise that the shift to immunological faecal occult blood tests will lead to a substantial reduction in mortality from colorectal cancer and perhaps even reduce its incidence. Conflict of interest None declared. References [1] Hewitson P, Glasziou P, Irwig L, et al. E.W. screening for colorectal cancer using the faecal occult blood test, Hemoccult. Cochrane Database of Systematic Reviews 2007. [2] Council recommendation of 2 December 2003 on cancer screening. Official Journal of the European Union 2003;I327:34–8.
[3] Faivre J, Dancourt V, Denis B, et al. Comparison between a guaiac and three immunochemical faecal occult blood tests in screening for colorectal cancer. European Journal of Cancer 2012 [Epub ahead of print]. [4] Faivre J, Dancourt V, Manfredi S, et al. Positivity rates and performances of immunochemical faecal occult blood tests at different cut-off levels within a colorectal cancer screening programme. Digestive and Liver Disease 2012;44:700–4. [5] Guittet L, Bouvier V, Guillaume E, et al. Colorectal cancer screening: why immunochemical faecal occult blood test performs as well with either one or two samples. Digestive and Liver Disease 2012;44:694–9. [6] Zappa M, Dardanoni G, Giorgi Rossi P, et al. The diffusion of screening programmes in Italy. Epidemiologia e Prevenzione 2009;35:3–7. [7] Wilschut JA, Hol L, Dekker E, et al. Cost-effectiveness analysis of a quantitative immunochemical test for colorectal cancer screening. Gastroenterology 2011;141, 1648–55 e1. [8] van Rossum LG, van Rijn AF, Laheij RJ, et al. Random comparison of guaiac and immunochemical fecal occult blood tests for colorectal cancer in a screening population. Gastroenterology 2008;135:82–90. [9] van Rossum LG, van Rijn AF, Laheij RJ, et al. Cutoff value determines the performance of a semi-quantitative immunochemical faecal occult blood test in a colorectal cancer screening programme. British Journal of Cancer 2009;101:1274–81. [10] Hol L, van Leerdam ME, van Ballegooijen M, et al. Screening for colorectal cancer: randomised trial comparing guaiac-based and immunochemical faecal occult blood testing and flexible sigmoidoscopy. Gut 2010;59:62–8. [11] Hol L, Wilschut JA, van Ballegooijen M, et al. Screening for colorectal cancer: random comparison of guaiac and immunochemical faecal occult blood testing at different cut-off levels. British Journal of Cancer 2009;100:1103–10.
Contents lists available at SciVerse ScienceDirect
Digestive and Liver Disease journal homepage: www.elsevier.com/locate/dld
Editorial
Faecal immunochemical tests: A valuable tool for colorectal cancer screening Côme Lepage a,b,c,∗ , Samia Hamza a,b,c a
Burgundy Digestive Cancer Registry, INSERM U866, 21079 Dijon Cedex, France University of Burgundy, France c University Hospital of Dijon, France b
Colorectal cancer is a major health problem in industrialized countries and fulfils the conditions required to justify mass screening of the general population. Population-based controlled studies performed in Europe have shown that guaiac faecal occult blood testing (G-FOBT) followed by colonoscopy to detect the cause of bleeding can reduce colorectal cancer mortality [1]. Nearly all published studies evaluated the Hemoccult II (Beckman Coulter Inc., Bea, USA) faecal occult blood test. Screening for colorectal cancer using FOBT has, therefore, been included in the European Code against Cancer and has been endorsed by the European Commission [2]. Despite its high specificity, Hemoccult has been criticized for its fairly low sensitivity and because it reacts with non-human haeme in food. For these reasons, attention has been given to alternative screening strategies, in particular, immunochemical faecal occult blood testing (I-FOBT). Accurate interpretation of G-FOBTs is not easy and requires well established laboratories. The development of quantitative I-FOBTs and of automated systems for the interpretation of the screening test has increased interest in I-FOBTs, as they minimise human error in test processing and allow excellent quality control. One limit of I-FOBTs was that globin (the measured component of haemoglobin in these tests) was not stable in the buffer and was prone to denaturation. Manufacturers have now modified the buffer to increase globin stability. None of the quantitative I-FOBT appeared to be clearly better than the others [3]. Moreover improved standardisation is necessary so that the tests can be compared directly. To date, there are no internationally agreed standards. In the current issue of Digestive and Liver Disease, two separate studies provide comparisons of the performance of Hemoccult II with that of three different available I-FOBTs. The results are of interest in that they concern subjects attending subsequent screening rounds, while most studies have reported data concerning the prevalent round. Faivre at al. [4] have added to our understanding of colorectal cancer screening using I-FOBT. The study provides a direct comparison of the performance of Hemoccult II given with one of the two studied immunochemical quantitative tests OC-Sensor (Eiken,
∗ Corresponding author at: BP 87900, 21079 Dijon, France. Tel.: +33 3 80 29 37 50; fax: +33 3 80 29 37 22. E-mail address: [email protected] (C. Lepage).
Tokyo, Japan) and FOB-Gold (Sentinel, for Beckman Coulter Inc., Milan, Italy), used with one or two-day sampling at different cutoff values in a large population-based cohort. It is therefore a major study since it allows the indirect comparison of two I-FOBTs with the reference test (Hemoccult), and also provides results at varying level of test positivity. The authors concluded that 2-day sampling, with at least one positive test, at a cut-off value situated between 150 and 200 ng/mL for OC-Sensor and the corresponding values of 176 and 234 ng/mL for FOB-Gold would be an acceptable strategy in France. However, they also state that one-day testing using a lower cut-off than the one previously described can be an alternative. Two-day sampling improves sensitivity but increases costs. Guitet et al. [5] in the same issue, provided further evidence using a qualitative marketed I-FOBT Magstream (Fujirebio Inc., Tokyo, Japan) using either one- or two-day sampling. The crude results of the Magstream 1000 automat analyzer were then derived through an equation provided by the manufacturer in order to be able to vary the level of test positivity. The authors stated that using the crude result, this test worked, in the target population, as a quantitative test. As in the previous study, identical performances in terms of detection rate were found. This study nicely highlights that using one test there is a compromise between the mean intensity of bleeding and the extent of bleeding fluctuation. This study is of major interest because it underlines the fact that identical performances can be obtained with one or two faecal samples provided a different cut-off value is chosen (for instance 39 mg/mL with one sample and 63 mg/mL with two samples and at least one positive test). As discussed by the authors, parameters other than test performance and participation must also be taken into account: the ease of sample collection and test interpretation, the performance of automated analysers, the stability of test samples over time in particular depending on the ambient temperature, and costeffectiveness analyses. Currently, one sampling strategy with the OC-Sensor test is used with success in Italy (100 ng/mL) [6]. It is also proposed in the Netherlands with a threshold of 50–75 ng/mL. In this regards several medical-economic studies have been performed over the last two years [7], and they all concluded that immunological tests were an effective alternative to the Hemoccult test. They also argued in favour of taking a single sample.
1590-8658/$36.00 © 2012 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.dld.2012.05.015
630
C. Lepage, S. Hamza / Digestive and Liver Disease 44 (2012) 629–630
Several key points of the I-FOBT test must be taken into account. Whatever the conditions, immunoassay tests are superior to Hemoccult [8–11]. These studies nicely highlight the fact that they are better accepted. These tests will allow the doubling of the cancer detection rate and will increase the adenoma detection rate by 3–4 times. The French Health Minister announced that these tests will be used for the National campaign for colorectal cancer screening from 2013. Thanks to these performance data, we can surmise that the shift to immunological faecal occult blood tests will lead to a substantial reduction in mortality from colorectal cancer and perhaps even reduce its incidence. Conflict of interest None declared. References [1] Hewitson P, Glasziou P, Irwig L, et al. E.W. screening for colorectal cancer using the faecal occult blood test, Hemoccult. Cochrane Database of Systematic Reviews 2007. [2] Council recommendation of 2 December 2003 on cancer screening. Official Journal of the European Union 2003;I327:34–8.
[3] Faivre J, Dancourt V, Denis B, et al. Comparison between a guaiac and three immunochemical faecal occult blood tests in screening for colorectal cancer. European Journal of Cancer 2012 [Epub ahead of print]. [4] Faivre J, Dancourt V, Manfredi S, et al. Positivity rates and performances of immunochemical faecal occult blood tests at different cut-off levels within a colorectal cancer screening programme. Digestive and Liver Disease 2012;44:700–4. [5] Guittet L, Bouvier V, Guillaume E, et al. Colorectal cancer screening: why immunochemical faecal occult blood test performs as well with either one or two samples. Digestive and Liver Disease 2012;44:694–9. [6] Zappa M, Dardanoni G, Giorgi Rossi P, et al. The diffusion of screening programmes in Italy. Epidemiologia e Prevenzione 2009;35:3–7. [7] Wilschut JA, Hol L, Dekker E, et al. Cost-effectiveness analysis of a quantitative immunochemical test for colorectal cancer screening. Gastroenterology 2011;141, 1648–55 e1. [8] van Rossum LG, van Rijn AF, Laheij RJ, et al. Random comparison of guaiac and immunochemical fecal occult blood tests for colorectal cancer in a screening population. Gastroenterology 2008;135:82–90. [9] van Rossum LG, van Rijn AF, Laheij RJ, et al. Cutoff value determines the performance of a semi-quantitative immunochemical faecal occult blood test in a colorectal cancer screening programme. British Journal of Cancer 2009;101:1274–81. [10] Hol L, van Leerdam ME, van Ballegooijen M, et al. Screening for colorectal cancer: randomised trial comparing guaiac-based and immunochemical faecal occult blood testing and flexible sigmoidoscopy. Gut 2010;59:62–8. [11] Hol L, Wilschut JA, van Ballegooijen M, et al. Screening for colorectal cancer: random comparison of guaiac and immunochemical faecal occult blood testing at different cut-off levels. British Journal of Cancer 2009;100:1103–10.