Survival outcome of patients with screening versus symptomatically detected colorectal cancers

The national Bowel Cancer Screening Programme has been rolled out nationwide following pilot screening in two health authorities in the UK. The aim of this study was to define overall 5-year survival of screen detected cancers and to compare the overall survival outcome of screened vs symptomatic patients over a 10-year period.

All patients with colorectal cancer treated at one trust in patients of screening age (50-69 years) during the pilot screening programme (2000-2008) were analysed. Patients were defined as screen detected or symptomatically detected. Disease pathology and recurrence data were obtained from the hospital's computerized results reporting system and mortality was cross-matched with data from the West Midlands Cancer Intelligence Network.

In all, 633 patients aged 50-69 were identified in the study period; 155 patients had a screen detected cancer and 478 did not. A log-rank test completed on survival outcomes indicated that survival was significantly worse in the symptomatic group. This difference persisted if only patients treated with curative intent were considered.

Survival outcome was significantly better in the screened vs the symptomatic population in all groups and also in those treated for curative intent. There was a trend towards better survival for screen detected cancer when compared stage for stage.