Evaluation of an immunological test for occult bleeding from colorectal neoplasia.

A study to determine the reliability of a recently described test, the faecal human haemoglobin test (FHH), specific for human blood, in the detection of colorectal neoplasia, is reported. All of nineteen patients with proven cancers studied were shown to have detectable blood in the stools. Three of five patients with polyps in this series also had detectable blood in the stools by this test. Although three of nineteen control subjects had positive tests, two of these were subsequently found to have bleeding sites, and the third was normal on follow up some weeks later. The findings are discussed in relation to the Hemoccult II (H-O) test results obtained in these subjects, and the implications for the possible future role for this test in screening for colorectal neoplasia.