Bowel cancer screening significantly reduces risk of bowel cancer death

In a study of people diagnosed with bowel cancer in 2006-2008, those invited to participate in the National Bowel Cancer Screening Program (NBCSP) were less likely to have died of bowel cancer before 2012, according to a report released today by the Australian Institute of Health and Welfare (AIHW). This finding is consistent with the evidence from the major bowel cancer screening trials of the 1990s.

The report, Analysis of bowel cancer outcomes for the National Bowel Cancer Screening Program, used data from 22,051 people diagnosed with bowel cancer, of which 4,327 had been invited to participate in the NBCSP when they turned 50, 55 or 65 during 2006-2008, and 17,724 were people of similar age who had not been invited to participate in the program in 2006-2008. It found that of the two groups, those not invited in 2006-2008 were 15% more likely to have died from bowel cancer by 31 December 2011.

'The reduced risk of death for those invited to participate in the bowel screening program was generally because their bowel cancers were detected at a less advanced stage, which is associated with better treatment options and outcomes,' said AIHW spokesperson Justin Harvey.

For the NBCSP invitees specifically, the mortality risk reduction was greatest for those whose bowel cancer was diagnosed by participation in the screening program, compared with bowel cancers later diagnosed in those who chose not to participate.

'The risk of death from bowel cancer was over 2.3 times higher in people who chose not to participate but later had a bowel cancer diagnosed by other means,' Mr Harvey said.

'The greatest contributing factor to the reduced risk of death from bowel cancer was the finding that, on average, screen-detected bowel cancers were at a less advanced stage at diagnosis.'

The screening test shows a high degree of accuracy. Among the NBCSP invitees who participated in screening, 83% of those diagnosed with bowel cancer within two years of their screen had received a positive result from the screening test (and a follow up with their GP was recommended), while 93% of those who did not go on to be diagnosed with bowel cancer had received a negative result from their screen (not requiring any further follow up).

The AIHW is a major national agency set up by the Australian Government to provide reliable, regular and relevant information and statistics on Australia's health and welfare.

Canberra, 2 December 2014

Further information: Mr Justin Harvey, AIHW, tel. 0450 677 562.