Faecal haemoglobin and faecal calprotectin as indicators of bowel disease in patients presenting to primary care with bowel symptoms.

Mowat C, Digby J, Strachan JA, Wilson R, Carey FA, Fraser CG and Steele RJC.

GP’s were encouraged to request samples for FIT and Calprotectin from symptomatic patients as they are referred to secondary care. Sample results were analysed and blinded to clinicians.

Results: 1043 patients returned samples. FHb was detectable in 57.6% (median 0.4µg/g, 95% CI 0.4 to 0.8; range 0-200). FC at 50µg/g or above was present in 60.0%. 755 patients (54.6% women, median age 64 years (range 16-90, IQR 52-73)) returned samples and completed colonic investigations. 103 patients had significant bowel disease; negative predictive values of FHb for colorectal cancer, higher-risk adenoma and IBD were 100%, 97.8% and 98.4%, respectively. Using cut-offs of detectable FHb and/or 200µg/g FC detected two further cases of IBD, one higher-risk adenoma and no additional cancers.

Read abstract

Low faecal haemoglobin concentration potentially rules out significant colorectal disease

McDonald J, Digby J, Innes C, Strachan JA, Carey FA, Steele RJC and Fraser G.

Faecal Hb concentrations were measured on single samples from 280 patients referred for lower gastrointestinal tract endoscopy from primary care in NHS Tayside who completed a faecal immunochemical test (FIT) for Hb and underwent subsequent endoscopy.

Results: Using a cut-off faecal Hb concentration of 50 ng Hb/ml buffer, negative predictive values of 100.0%, 94.4%, 93.4% and 93.9% were found for cancer, HRA, LRA and IBD. Patients with reasons for referral other than rectal bleeding and family history did not have high faecal Hb concentrations.

Read abstract

A quantitative immunochemical fecal occult blood test for colorectal neoplasia.

Levi Z, Rozen P, Hazazi R, Vilkin A, Waked A, Maoz E, Birkenfeld S, Leshno M and Niv Y. 2007. Ann Intern Med; 146:244-55 .

1000 consecutive ambulatory patients--some asymptomatic but at increased risk for colorectal neoplasia and some symptomatic--who were undergoing elective colonoscopy and volunteered to prepare immunochemical FOBTs. The hemoglobin content of 3 bowel movements was measured, and the highest value was compared with colonoscopy findings.

Results: Colonoscopy identified clinically significant neoplasia in 91 patients (cancer in 17 patients and advanced adenomas in 74 patients). Using 3 immunochemical FOBTs and a hemoglobin threshold of 75 ng/mL of buffer, sensitivity and specificity were 94.1% (95% CI, 82.9% to 100.0%) and 87.5% (CI, 85.4% to 89.6%), respectively, for cancer and 67% (CI, 57.4% to 76.7%) and 91.4% (CI, 89.6% to 93.2%), respectively, for any clinically significant neoplasia.

Read abstract

Diagnostic accuracy of the faecal immunochemical test for colorectal cancer in symptomatic patients: comparison with NICE and SIGN referral criteria.

Cubiella J, Salve M, Díaz-Ondina M, Vega P, Alves MT, Iglesias F, Sánchez E, Macía P, Blanco I, Bujanda L, Fernández-Seara. Colorectal Dis 2014;16:O273-82.

A multicentre, prospective, blind study of diagnostic tests was carried out in two Spanish health areas. In 787 symptomatic patients referred for diagnostic colonoscopy, we determined whether patients met NICE and SIGN referral criteria. All patients performed one FIT determination (OC Sensor).

Results: We detected CRC in 97 (12.3%) patients; 241 (30.6%) had an FIT ≥ 100 ng/ml and 300 (38.1%) and 473 (60.1%) met NICE and SIGN referral criteria. The FIT had a higher sensitivity for CRC detection than NICE criteria (87.6%, 61.9%; P < 0.001) and SIGN criteria (82.5%; P = 0.4). The specificity of FIT was also higher than NICE and SIGN criteria (77.4%, 65.2%, 42.7%; P < 0.001). The odds ratios of FIT, NICE and SIGN criteria for the diagnosis of CRC were 24.24 (95% CI 12.91-45.53), 3.04 (95% CI 1.96-4.71) and 3.51 (95% CI 2.03-6.06). The NNS to detect a CRC in individuals with an FIT ≥ 100 ng/ml was 2.83 (95% CI 2.4-3.41) and in individuals who met NICE and SIGN criteria it was 5 (95% CI 3.98-6.37) and 5.95 (95% CI 4.85-7.35).

Read abstract

Random Comparison of Guaiac and Immunochemical Fecal Occult Blood Tests for Colorectal Cancer in a Screening Population.

van Rossum LG, van Rijn AF, Laheij RJ, van Oijen MG, Fockens P, van Krieken HH, Verbeek AL, Jansen JB and Dekker E. 2008. Gastroenterology 135(1):82-90.

Randomised, controlled trial; comparison of OC-Sensor FIT with a cut-off of 100 ng/ml versus gFOBT in an asymptomatic Dutch screening collective (n= 20,993, aged 50-75). Verification of positive test results by colonoscopy.

Results: Participation rate for FIT is 13% higher and detection rates for colorectal carcinoma and advanced neoplasms are significantly higher than with gFOBT.

Read abstract

Screening for Colorectal Cancer: Random Comparison of Guaiac and Immunochemical Faecal Occult Blood Testing at Different Cut-Off Levels.

Hol L, Wilschut JA, van Ballegooijen M, van Vuuren AJ, van der Valk H, Reijerink J, van der Togt ACM, Kuipers EJ, Habbema JDF, van Leerdam ME. 2009a. Br J Cancer 100(7):1103-10.

Randomised, controlled trial; comparison of OC-Sensor FIT with various different cut-off values (50 to 200 ng/ml) versus gFOBT in an asymptomatic Dutch screening collective (n= 10,001, aged 50-74); verification of positive test results by colonoscopy.

Results: Participation rate for FIT is 12% higher and detection rates for advanced neoplasms in all of the cut-off values tested significantly higher than with gFOBT.

Read article

Immunochemical Fecal Occult Blood Testing Is Equally Sensitive for Proximal and Distal Advanced Neoplasia

de Wijkerslooth TR, Stoop EM, Bossuyt PM, Meijer GA, van Ballegooijen M, van Roon AH, Stegeman I, Kraaijenhagen RA, Fockens P, van Leerdam ME and others. 2012. Am J Gastroenterol 107(10):1570-8.

Direct comparison between OC-Sensor FIT and colonoscopy in an asymptomatic Dutch screening collective (n= 1256, aged 50-75 years).  Calculation of the sensitivity, specificity, predictive scores for the detection of colorectal carcinoma as well as advanced neoplasms (carcinomas + advanced adenomas) at various different cut-off scores.

Results: With a single OC-Sensor FIT test with low cut-off score, nine out of ten participants with colorectal carcinoma and four out of ten with advanced neoplasms were detected. The sensitivity for the detection of proximal and distal advanced neoplasms is the same.

Read abstract

Colonoscopy Versus Fecal Immunochemical Testing in Colorectal-Cancer Screening.

Quintero E, Castells A, Bujanda L, Cubiella J, Salas D, Lanas A, Andreu M, Carballo F, Morillas JD, Hernandez C and others. 2012. N Engl J Med 366(8):697-706.

Randomised controlled trial (Spain), comparison between bi-annual FIT screening OC-Sensor (cut-off of 75 ng/ml) versus colonoscopy in an asymptomatic screening collective (n= 57,404, aged 50-69); verification of positive FIT by colonoscopy.

Results from the first round of screening: The participation rate in the FIT group is approximately 10% higher than in the colonoscopy group. In the FIT group 33 individuals with colorectal carcinoma were detected (231 with advanced adenoma); in the colonoscopy group 30 individuals with CRC (514 with advanced adenoma).

Read article

Superior Diagnostic Performance of Faecal Immunochemical Tests for Haemoglobin in a Head-to-Head Comparison with Guaiac Based Faecal Occult Blood Test among 2235 Participants of Screening Colonoscopy.

Brenner H, Tao S. 2013. Eur J Cancer 49(14):3049-54.

Direct comparison between gFOBT and quantitative FIT OC-Sensor, Hb ELISA, Hb/Hapto complex ELISA in 2,235 participants of colonoscopy screening.

For this comparison the positivity rates for the quantitative FIT were adjusted to those for the gFOBT and the test parameters calculated accordingly.

Results: OC-Sensor FIT showed significantly the highest sensitivity (73.3%) for detecting colorectal carcinoma by comparison with Hb ELISA (60%), Hb Hapto complex ELISA (53.3%) and gFOBT (33.3%).

Limitation of this trial: The harvesting, transportation and storage of the samples for the OC-Sensor FIT were not carried out using manufacturer-specific sample tubes with stabilising buffer solution.

Read abstract