Local impact of the English arm of the UK Bowel Cancer Screening Pilot study

Abstract

Background: The English arm of the UK Bowel Cancer Screening Pilot study recently concluded its third round. The primary aim was to assess the impact of faecal occult blood test (FOBT) screening on the detection of symptomatic (non-screen-detected) cancers within the target age group (50-69 years). The secondary aim was to assess differences between screened and non-screened cohorts in Dukes' classification at diagnosis.

Methods: This population-based study utilized retrospective analysis of existing validated colorectal cancer (CRC) data over 5 years (April 2000 to March 2005), encompassing rounds one and two of screening.

Results: There was a 23 per cent (P = 0.011) reduction in the diagnosis of over the 5 years. Presentations with symptomatic cancer reduced by 49 per cent (P = 0.049), with a proportionate (2.6-fold) rise in the detection of screened (asymptomatic) malignancy. Cancers were diagnosed at an earlier stage in the screened population, with significantly more Dukes' A tumours than in the non-screen-detected cohort (P < 0.001) and an estimated odds ratio of 0.27 (95 per cent confidence interval 0.08 to 0.91) (P = 0.035) for Dukes' 'D' cancers.

Conclusion: FOBT screening resulted in a significant reduction in the number of symptomatic cancers detected within the target age group. Tumours detected by screening were diagnosed at an earlier pathological stage.