Slipping through the bowel cancer screening programme

Colorectal cancer is common and a leading cause of cancer death. Faecal occult blood screening has been shown to reduce mortality. The aim of this study was to identify patients in Gloucestershire with a new diagnosis of colorectal cancer who had previously been screened via the Bowel Cancer Screening Programme (BCSP).

Between 2006 and 2009, 1030 patients were diagnosed with colorectal cancer. Of these 237 (23%) had been invited to be screened via the BCSP. Their clinical notes were analysed.

Fifty-seven (24%) of the 237 patients had previously had a negative faecal occult blood result. Thirty-three (14%) had their cancer discovered as part of the BCSP. Seventy (30%) had already been diagnosed with colorectal cancer prior to invitation, 62 (26%) did not respond to the invitation, nine (4%) were registered outside Gloucestershire and had therefore not been invited, and three (3%) had died before the invitation. Of the 57 patients with a negative faecal occult blood test, 47 (83%) had colorectal cancer staged Dukes B or C, and 34 (60%) had a rectal or sigmoid cancer.

Patients will present with colorectal cancer despite having been invited to participate in the BCSP, with many having received a negative faecal occult blood test. This could be considered a high false negative rate.