Comparison of a guaiac based and an immunochemical faecal occult blood test in screening for colorectal cancer in a general average risk population

Guittet, I.; Bouvier, V.; Mariotte, N.; Vallee, J. P.; Arsène, D.; Boufreux, S.; Tichet, J.; Launoy, G.
February 2007
Gut;Feb2007, Vol. 56 Issue 2, p210
Academic Journal
Background: The guaiac faecal occult blood test (G-FOBT) is recommended as a screening test for colorectal cancer but its low sensitivity has prevented its use throughout the world. Methods: We compared the performances of the reference G-FOBT (non-rehydrated Hemoccult II test) and the immunochemical faecal occult blood test (I-FOBT) using different positivity cut-off values in an average risk population sample of 10 673 patients who completed the two tests. Patients with at least one test positive were asked to undergo colonoscopy. Results: Using the usual cut-off point of 20 ng/ml haemoglobin, the gain in sensitivity associated with the use of I-FOBT (50% increase for cancer and 256% increase for high risk adenoma) was balanced by a decrease in specificity. The number of extra false positive results associated with the detection of one extra advanced neoplasia (cancer or high risk adenoma) was 2.17 (95% confidence interval 1 .65-2.85). With a threshold of 50 ng/ml, 1-FOBI detected more than twice as many advanced neoplasias as the G-FOBT (ratio of sensitivity = 2.33) without any loss in specificity (ratio of false positive rate = 0.99). With a threshold of 75 ng/ml, associated with a similar positivity rate to G-FOBT (2.4%), the use of I-FOBT allowed a gain in sensitivity of 90% and a decrease in the false positive rate of 33% for advanced neoplasia. Conclusions: Evidence in favour of the substitution of G-FOBT by l-FOBT is increasing, the gain being more important for high risk adenomas than for cancers. The automated reading technology allows choice of the positivity rate associated with an ideal balance between sensitivity and specificity.


Related Articles

  • Comparison of a guaiac and an immunochemical faecal occult blood test for the detection of colonic lesions according to lesion type and location. Guittet, L.; Bouvier, V.; Mariotte, N.; Vallee, J. P.; Levillain, R.; Tichet, J.; Launoy, G. // British Journal of Cancer;4/21/2009, Vol. 100 Issue 8, p1230 

    We investigated variations in sensitivity of an immunochemical (I-FOBT) and a guaiac (G-FOBT) faecal occult blood test according to type and location of lesions in an average-risk 50- to 74-year-old population. Screening for colorectal cancer by both non-rehydrated Haemoccult II G-FOBT and...

  • Using CT colonography as a triage technique after a positive faecal occult blood test in colorectal cancer screening. Liedenbaum, M. H.; van Rijn, A. F.; de Vries, A. H.; Dekker, H. M.; Thomeer, M.; van Marrewijk, C. J.; Hol, L.; Dijkgraaf, M. G. W.; Fockens, P.; Bossuyt, P. M. M.; Dekker, E.; Stoker, J. // Gut;Sep2009, Vol. 58 Issue 9, p1242 

    Objective: The purpose of this study was to evaluate the effectiveness of CT colonography (CTC) as a triage technique in faecal occult blood test (FOBT)-positive screening participants. Methods: Consecutive guaiac (G-FOBT) and immunochemical (I-FOBT) FOBT-positive patients scheduled for...

  • Prospective evaluation of methylated SEPT9 in plasma for detection of asymptomatic colorectal cancer. Church, Timothy Robert; Wandell, Michael; Lofton-Day, Catherine; Mongin, Steven J.; Burger, Matthias; Payne, Shannon R.; Castaños-Vélez, Esmeralda; Blumenstein, Brent A.; Rösch, Thomas; Osborn, Neal; Snover, Dale; Day, Robert W.; Ransohoff, David F. // Gut;Feb2014, Vol. 63 Issue 2, p317 

    Background As screening methods for colorectal cancer (CRC) are limited by uptake and adherence, further options are sought. A blood test might increase both, but none has yet been tested in a screening setting. Objective We prospectively assessed the accuracy of circulating methylated SEPT9 DNA...

  • Population-based screening for colorectal cancer with faecal occult blood test-do we really have enough evidence? Ekelund, Göran; Manjer, Jonas; Zackrisson, Sophia // International Journal of Colorectal Disease;Nov2010, Vol. 25 Issue 11, p1269 

    Introduction: Population-based randomised controlled trials (RCT) have shown that invitation to biennial screening with faecal occult blood testing (FOBT) during 10 or more years reduced colorectal cancer-specific mortality. These results have stimulated plans to introduce mass screening in...

  • Screening and Diagnosis.  // Current Medical Literature: Colorectal Cancer;2011, Vol. 4 Issue 4, p120 

    Reviews of the articles "High detection rate of adenomas in familial colorectal cancer," by H. Morreau and colleagues, "The reduction in colorectal cancer mortality after colonoscopy varies by site of the cancer," by H. Singh and colleagues, and "Level of fellowship training increase adenoma...

  • Narrow band imaging for colonoscopic surveillance in hereditary non-polyposis colorectal cancer. East, J. E.; Suzuki, N.; Stavrinidis, M.; Guenther, I.; Thomas, H. J. W.; Saunders, B. P. // Gut;Jan2008, Vol. 57 Issue 1, p65 

    Background: Colonoscopic surveillance for hereditary non-polyposis colorectal cancer (HNPCC) reduces death rates, but early interval cancers still occur, probably due to missed small, aggressive adenomas. Narrow band imaging (NBI), a novel endoscopic technology, highlights superficial mucosal...

  • Colorectal Neoplasms and Barrett's Esophagus. Tripp, Michael R.; Sampliner, Richard E.; Kogan, Frederick J.; Morgan, Timothy R. // American Journal of Gastroenterology;Nov1986, Vol. 81 Issue 11, p1063 

    Prospective colonoscopic study of 36 patients with Barrett's esophagus found colorectal adenomas in 33% of patients. Of patients aged less than 60, four of 17 (24%) had adenomas, while patients aged 60 or more had adenomas in eight of 19 (42%) cases. All adenomas were ≤10 mm diameter. No...

  • Indigocarmine added to the water exchange method enhances adenoma detection - a RCT. Leung, Joseph; Mann, Surinder; Siao-Salera, Rodelei; Ngo, Catherine; McCreery, Randy; Canete, Wilhemina; Leung, Felix // Journal of Interventional Gastroenterology;7/ 1/2012, Vol. 2 Issue 3, p106 

    Purpose: Chromoendoscopy with dye spray and the water method both increase adenoma detection. Hypothesis: Adding indigocarmine to the water method will enhance further the effectiveness of the latter in adenoma detection. Methods: Screening colonoscopy was performed with the water method...

  • Sporadic Duodenal Adenoma and the Association With Colorectal Neoplasia: A Case-Control Study. Ramsoekh, Dewkoemar; Van Leerdam, Monique E.; Dekker, Evelien; Ouwendijk, Rob T.; Van Dekken, Herman; Kuipers, Ernst J. // American Journal of Gastroenterology;Jun2008, Vol. 103 Issue 6, p1505 

    OBJECTIVES: Sporadic duodenal adenomas are an uncommon finding. It is not clear whether patients with sporadic duodenal adenoma have a greater risk for colorectal neoplasia and should undergo colonoscopy. The aims of the present study were to estimate the prevalence of colorectal neoplasia in...


Read the Article


Sign out of this library

Other Topics