Bowel cancer – incidence and mortality

• Bowel cancer is one of the most common cancers in both males and females. As the greatest risk factor is older age, the number of people in the ACT with bowel cancer is likely to increase as the proportion of older people in our population grows.
• Bowel cancer can develop insidiously over many years, which can often result in late diagnosis and poor long-term survival; however, when detected early, 90% of cases can be treated successfully. The National Bowel Cancer Screening Program (NBCSP) was introduced in 2006 to target the screening of Australians aged 50 to 74 years, and recent evidence suggests this is already reducing colorectal cancer deaths.¹
• A number of risk factors can increase a person’s chance of developing bowel cancer. Many of these are modifiable, and include physical inactivity, high alcohol consumption, smoking and excess body fat.¹
• In 2019 there were 199 new cases of bowel cancer diagnosed in ACT residents (56.8% in males and 43.2% in females). The age-standardised incidence rate for the ACT in 2019 was 46.4 cases per 100,000 people (55.9 for males and 37.5 for females) compared to 51.9 cases per 100,000 people for Australia in 2019 (58.9 for males and 45.7 for females)*.^2,3
• Overall, the bowel cancer incidence rate in the ACT has declined from 61.3 per 100,000 population in 1994 to 53.3 per 100,000 people in 2019.2
• In 2018, 54 people (51.9% males and 48.1% females) who lived in the ACT at the time of their bowel cancer diagnosis died from bowel cancer. In 2018, the age-standardised mortality rate for the ACT was 13.2 deaths per 100,000 people (15.4 for males and 11.5 for females) compared to 17.3 deaths per 100,000 people for Australia (20.5 for males and 14.4 for females)*.^2,3
• Five-year relative survival for bowel cancer has improved over time, from 56.1% in the period 1988–1997 to 71.2% for the period 2008–2017, due to enhanced treatment and, possibly, earlier diagnosis. While there were no significant differences in survival between males and females, those aged under 65 had significantly better survival than those aged 65 and older (75.4% and 69.1%, respectively). It is hoped that population screening for bowel cancer will contribute to further improvements in the years to come.^2-9

*The national 2019 cancer incidence data reported by the Australian Institute of Health and Welfare are estimates based on previous years’ trends. By contrast, all ACT-specific incidence data reported here utilise actual ACT data.

References

1. Australian Institute of Health and Welfare (AIHW). National Bowel Cancer Screening Program: monitoring report 2018. Canberra: AIHW; 2018 [cited 2022 Apr 6]. Available from: https://www.aihw.gov.au/reports/cancer-screening/national-bowel-cancer-screening-program-2018/contents/summary.

2. ACT Cancer Registry. Canberra: ACT Cancer Registry; 2022 (unpublished data).

3. Australian Institute of Health and Welfare (AIHW). Cancer in Australia 2021. Canberra: AIHW; 2021 [cited 2022 Apr 6]. Available from: https://www.aihw.gov.au/reports/cancer/cancer-in-australia-2021/data.

4. Ananda S, Wong H, Faragher I, et al. Survival impact of the Australian National Bowel Cancer Screening Programme. Intern Med J 2016; 46(2):166-171.

5. Australian Bureau of Statistics (ABS). Life Tables, States, Territories and Australia, 2015-2017. Canberra: ABS; 2019 [cited 2022 Apr 6]. Available from: https://www.abs.gov.au/AUSSTATS/abs@.nsf/Lookup/3302.0.55.001Main+Features12015-2017?OpenDocument=.

6. ABS. Life Tables, States, Territories and Australia, 2014-2016. Canberra: ABS; 2018 [cited 2022 Apr 6]. Available from: https://www.abs.gov.au/AUSSTATS/abs@.nsf/Lookup/3302.0.55.001Main+Features12014-2016?OpenDocument=.

7. ABS. Life Tables, States, Territories and Australia, 2013-2015. Canberra: ABS; 2017 [cited 2022 Apr 6]. Available from: https://www.abs.gov.au/AUSSTATS/abs@.nsf/Lookup/3302.0.55.001Main+Features12013-2015?OpenDocument=.

8. ABS. Life Tables, States, Territories and Australia, 2012-2014. Canberra: ABS; 2016 [cited 2022 Apr 6]. Available from: https://www.abs.gov.au/AUSSTATS/abs@.nsf/Lookup/3302.0.55.001Main+Features12012-2014?OpenDocument=.

9. ABS. Life Tables, States, Territories and Australia, 2011-2013. Canberra: ABS; 2015 [cited 2022 Apr 6]. Available from: https://www.abs.gov.au/AUSSTATS/abs@.nsf/Lookup/3302.0.55.001Main+Features12011-2013?OpenDocument=.

The authors wish to thank the Registries of Births, Deaths and Marriages, the Coroners and the National Coronial Information System for enabling the cause of death unit record file data to be used for this publication.