Hot topics in bowel cancer screening

Bowel cancer screening was high on the agenda at DDF 2015, as the director of the NHS cancer screening programme, Professor Julietta Patnick CBE, discussed the ‘current position in England and the potential for the future’. She provided an overview of the epidemiology of colorectal cancer, explaining that 15,708 deaths and 40,695 new cases were recorded in 2010. 

Population screening in the UK commenced in July 2006 with the guaiac faecal occult blood test (FOBT), and has been proven to be effective in reducing colorectal cancer mortality through early detection. Prof Patnick highlighted a trial conducted in Minnesota, US, which randomly assigned 46,551 men and women aged 50 to 80 years to one of three arms: colorectal cancer screening with guaiac-based, rehydrated FOBT every year (15,570), every two years (15,587), or control (15,394). This trial demonstrated that annual FOBT screening decreased mortality from colorectal cancer by 33% after 18 years of follow-up and that biennial testing resulted in a 21% mortality reduction. 

A trial undertaken in Nottingham, UK, showed a reduction in mortality of 15%, while another study undertaken in Funen, Denmark, showed a reduction in mortality of around 15%-18%. Prof Patnick commented that, because the Minnesota trial involved rehydration of the guaiac, a large number of colonoscopies were performed, which ultimately led to a reduction in incidence after 18 years. The fact that the UK and Denmark studies did not show the same levels of reduction in incidence, was probably due to the fact that the guaiac was not rehydrated in these studies and fewer colonoscopies were performed, she theorised.