Faecal occult blood testing in areas of high incidence and mortality; the effect of screening the population aged 50 to 59

Abstract

In central Liverpool, the incidence of colorectal cancer (CRC) is 119% of the national average. Currently, screening is offered to those aged 60-70 through the National Bowel Cancer screening programme. A theoretical model showing the effect of the introduction of biennial screening in individuals aged 50-59 has been applied to the population of central Liverpool. The impact of screening using faecal occult blood testing (FOBT) in individuals aged 50-59 in central Liverpool (n = 47,440; males 23,312) was assessed by a model based on three levels of compliance. After modelling, the positive FOBT result for increased incidence of CRC, the positive predictive value for adenoma and cancer detection was calculated using age-specific positivity rates. The results indicate that between 120 and 162 new diagnoses of CRC per 100,000 population aged 50-59 could be detected by biennial screening, dependent on compliance rates. Screening individuals aged 50-59 can identify early cancers and significant adenomas, which may contribute to a reduction in the expected high mortality rate found in this geographical area.