The content of this website is intended for healthcare professionals only

Faecal blood testing best to spot cancer and cost-effective

Annual immunochemical testing of faeces reduces colorectal cancer risk

Louise Prime

Thursday, 25 November 2010

Annual screening using faecal immunological testing not only reduces the risk of colorectal cancer and related deaths, it also cuts health care costs compared with other screening strategies or no screening at all, research has shown. The economic evaluation is published in PLoS Medicine this week.

The authors say that testing for blood in faeces has high sensitivity and high specificity for colorectal cancer and could also be more acceptable to patients than other methods of screening for the disease.

Although clinical guidelines recommend colorectal cancer screening in people of 50 years old onwards if they are deemed ‘average risk’ for the disease, in the UK and some other countries there is no population-based screening for colorectal cancer; and in others there is often no choice of screening method.

These researchers conducted a full economic evaluation of different methods of colorectal cancer screening: guaiac-based faecal occult blood test (FOBT) or faecal immunochemical test (FIT) annually, faecal DNA every 3 years, flexible sigmoidoscopy or computed tomographic colonography every 5 years and colonoscopy every 10 years.

They used computer modelling of two hypothetical groups of average-risk patients – aged 50-64 and aged 65-75, with no family history of colorectal cancer. Their evaluation took account of all medical and non-medical costs of each method.

They found that compared with other screening methods and with no screening at all, annual faecal immunochemical testing was the least costly strategy. It was also the most effective – it dramatically reduced the number of deaths from colorectal cancer in this patient group, from 1393 per 100,000 to 457.

The authors say: “Although it may seem counter-intuitive that screening with FIT could be even more effective than colonoscopy, this is due to the more frequent screening interval with FIT. In base case analyses, and consistent with current guidelines, screening with FIT was done annually compared to every 10 years with colonoscopy.

“Therefore, even though the test performance of a single FIT test was inferior to colonoscopy, there were more opportunities to identify previously missed pathology with FIT compared to colonoscopy.”

They conclude: “Our results are robust suggesting that screening for CRC with FIT should be considered the modality of choice for average risk patients between the ages of 50 and 75 in North America.

“Health policy decision makers should consider prioritising funding for colorectal cancer screening using faecal immunochemical testing.”

Registered in England and Wales. Reg No. 2530185. c/o Wilmington plc, 5th Floor, 10 Whitechapel High Street, London E1 8QS. Reg No. 30158470