Colonoscopies really should be done in people who have abnormal faecal occult blood testing, in those people where there’s a strong family history of colon cancer, particularly in young members of the family, or in people where there is a known abnormality, such as polyps in the colon, which need to be followed up on a regular basis. or a familial polyp condition.

Professor Michael Boyer is Medical Oncologist at Chris O’Brien Lifehouse