Faecal haemoglobin concentration is related to severity of colorectal neoplasia
- Jayne Digby1,
- Callum G Fraser2,
- Francis A Carey3,
- Paula J McDonald1,
- Judith A Strachan1,
- Robert H Diament4,
- Margaret Balsitis5,
- Robert J C Steele6
- 1Scottish Bowel Screening Centre, Kings Cross Hospital, Dundee, UK
- 2Centre for Research into Cancer Prevention and Screening, Ninewells Hospital and Medical School, Dundee, UK
- 3Department of Pathology, Ninewells Hospital and Medical School, Dundee, UK
- 4Department of Surgery, Crosshouse Hospital, Kilmarnock, Ayrshire, UK
- 5Department of Pathology, Crosshouse Hospital, Kilmarnock, Ayrshire, UK
- 6University Department of Surgery and Molecular Oncology, Ninewells Hospital and Medical School, Dundee, UK
- Correspondence to Jayne Digby, Scottish Bowel Screening Research Unit, Kings Cross Hospital, Clepington Road, Dundee DD3 8EA, UK;
- Received 7 January 2013
- Revised 17 January 2013
- Accepted 23 January 2013
- Published Online First 15 February 2013
Aims Guaiac faecal occult blood tests are being replaced by faecal immunochemical tests (FIT). We investigated whether faecal haemoglobin concentration (f-Hb) was related to stage in progression of colorectal neoplasia, studying cancer and adenoma characteristics in an evaluation of quantitative FIT as a first-line screening test.
Methods We invited 66 225 individuals aged 50–74 years to provide one sample of faeces. f-Hb was measured on samples from 38 720 responders. Colonoscopy findings and pathology data were collected on the 943 with f-Hb≥400 ng Hb/ml (80 µg Hb/g faeces).
Results Of the 814 participants with outcome data (median age: 63 years, range 50–75, 56.4% male), 39 had cancer, 190 high-risk adenoma (HRA, defined as ≥3 or any ≥10 mm) and 119 low-risk adenoma (LRA). 74.4% of those with cancer had f-Hb>1000 ng Hb/ml compared with 58.4% with HRA, and 44.1% with no pathology. Median f-Hb concentration was higher in those with cancer than those with no (p<0.002) or non-neoplastic (p<0.002) pathology, and those with LRA (p=0.0001). Polyp cancers had lower concentrations than more advanced stage cancers (p<0.04). Higher f-Hb was also found in those with HRA than with LRA (p<0.006), large (>10 mm) compared with small adenoma (p<0.0001), and also an adenoma displaying high-grade dysplasia compared with low-grade dysplasia (p<0.009).
Conclusions f-Hb is related to severity of colorectal neoplastic disease. This has ramifications for the selection of the appropriate cut-off concentration adopted for bowel screening programmes.