Faecal immunochemical tests for occult blood testing should not be used outside of bowel screening: an audit of a large general practice
Ui Ho Byun 1 5 , Neil Anderson 2 , Arlo Upton 3 , Paul Frankish 41 Department of Surgery, University of Auckland, 85 Park Road, Grafton, Auckland, New Zealand.
2 Coast to Coast Healthcare, 220 Rodney St, Wellsford, Auckland, New Zealand.
3 Southern Community Laboratories, 472 George Street, Dunedin, New Zealand.
4 Waitemata District Health Board, 124 Shakespeare Road, Takapuna, Auckland, New Zealand.
5 Corresponding author. Email: ubyu572@aucklanduni.ac.nz
Journal of Primary Health Care 11(3) 259-264 https://doi.org/10.1071/HC18068
Published: 3 September 2019
Journal Compilation © Royal New Zealand College of General Practitioners 2019. This is an open access article licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
Abstract
INTRODUCTION: The faecal immunochemical test (FIT) detects small quantities of human haemoglobin in faeces. This test has increasingly become the screening tool of choice in bowel cancer screening programmes worldwide, including New Zealand’s upcoming national screening programme.
AIM: This study audited the appropriate use of faecal immunochemical tests (FIT) in general practice as current recommendations discourage the use of FIT outside the National Bowel Screening Programme.
METHODS: Data on all FIT requested by a multiclinic general practice serving 16 000 patients from May 2017 to May 2018 were extracted from clinical records. Patient characteristics, results of tests, clinical rationale for the test, number of referrals and results and the completeness of clinical evaluation were recorded.
RESULTS: In all, 184 patients received an FIT, with 13 (7.1%) positive and 145 (78.8%) negative tests, and 26 (14.1%) tests declined by the laboratory. Nine patients (69.2%) with a positive FIT, 12 patients (8.1%) with a negative FIT and one patient (3.8%) with a declined test were referred to gastroenterology services. Seven colorectal cancers were detected, all in patients with a positive FIT who were aged between 67 and 91 years. FIT was requested most for changes in bowel habit (53%) and blood in stool (15%); 10% of tests were ordered for reassurance and 9% did not record an indication for the test. Two general practitioners (of 17 in the practice) accounted for over half of all tests requested.
CONCLUSIONS: Because FIT is only a screening tool for colorectal cancer, direct referral is recommended for symptomatic patients. Although cancers were detected only in patients with positive FITs, these patients would have qualified for direct referral for definitive investigation, and a referral was made concurrently. Awaiting test results may also delay necessary referrals and a negative FIT may produce false reassurance.
KEYwords: Faecal occult blood test (iFOBT); gastrointestinal; family practice.
References
[1] Best Practice Advocacy Centre. Appropriate use of the faecal occult blood test for colorectal cancer. 2012. [Cited 2018 June 17]. Available from: https://bpac.org.nz/BT/2012/June/06_faecal_occult.aspx[2] Ministry of Health. About the National Bowel Screening Programme. 2018. [Cited 2018 June 17]. Available from: https://www.timetoscreen.nz/bowel-screening/about-the-national-bowel-screening-programme/
[3] Labtests. Consultation document: faecal occult blood testing in the Auckland and Northland regions. 2017. [Cited 2018 June 17]. Available from: https://www.labtests.co.nz/images/News/E_Updates/171127_Consultation_FOB_testing.pdf
[4] Lee JK, Liles EG, Bent S, et al. Accuracy of fecal immunochemical tests for colorectal cancer: systematic review and meta-analysis. Ann Intern Med 2014; 160 171–81.
| Accuracy of fecal immunochemical tests for colorectal cancer: systematic review and meta-analysis.Crossref | GoogleScholarGoogle Scholar | 24658694PubMed |
[5] Robertson DJ, Lee JK, Boland CR, et al. Recommendations on fecal immunochemical testing to screen for colorectal neoplasia: a consensus statement by the US Multi-Society Task Force on colorectal cancer. Gastroenterol 2017; 152 1217–1237.e3.
| Recommendations on fecal immunochemical testing to screen for colorectal neoplasia: a consensus statement by the US Multi-Society Task Force on colorectal cancer.Crossref | GoogleScholarGoogle Scholar |
[6] Guidance for Best Practice Management in the National Bowel Screening Programme. Consultation document. Wellington: Ministry of Health; 2018.
[7] National Ethics Advisory Committee. Ethical guidelines for observational studies: observational research, audits and related activities. Revised edition. Wellington: Ministry of Health; 2012.
[8] Hamilton W, Round A, Sharp D, Peters TJ. Clinical features of colorectal cancer before diagnosis: a population-based case-control study. Br J Cancer 2005; 93 399–405.
| Clinical features of colorectal cancer before diagnosis: a population-based case-control study.Crossref | GoogleScholarGoogle Scholar | 16106247PubMed |
[9] Ministry of Health. Referral criteria for direct access outpatient colonoscopy or computed tomography colonography. 2019. [Cited 2019 April 23]. Available from: https://www.health.govt.nz/publication/referral-criteria-direct-access-outpatient-colonoscopy-or-computed-tomography-colonography
[10] National Institute for Heath and Care Excellence (NICE). Suspected cancer: recognition and referral. 2015. [Cited 2018 June 17]. Available from: https://www.nice.org.uk/guidance/ng12
