Introduction: primary prevention
Colorectal cancer is the second most common non-skin cancer occurring in men and women in Australia, and the second most common cause of cancer death. Although mortality from the disease has been decreasing over recent decades, the incidence is still rising slowly.
Many observational studies have provided evidence of dietary associations with colorectal cancer risk. A limited number of randomised controlled trials (RCTs) also support diet and lifestyle advice to reduce colorectal cancer risk. Colorectal cancer is the second most preventable cancer after lung cancer. Table 2.1 shows the proportion of incident colorectal cancer cases diagnosed in 2010 in Australia attributable to lifestyle and environmental factors (all both males and females).
Table 2.1 Proportion of incident colorectal cancer cases diagnosed in Australia attributable to lifestyle and environmental factors[edit source]
|Lifestyle/environmental factor||Proportion (%)|
|Overweight and obesity||9.0|
|Insufficient physical activity||4.8|
|Diet – insufficient fibre||17.6|
|Diet – red and processed meat||17.6|
|Population attributable fraction combined||49.8|
Proportions (%) presented are for the entire Australian population (0–-85+ years), all persons (male/female); Abridged table, adapted from Whiteman et al 2015 with permission from the publisher (in progress)
In the adult white population in the USA, it has been estimated that 60% and 59% of colorectal cancer incidence for women and men, respectively, could be prevented by lifestyle factors. However, although these lifestyle and environmental risk factors are well described, there are no data yet available to indicate that interventions to avoid or modify favourably the factors has been less convincing except for some diet studies.
Prevention of colorectal cancer includes:
- primary prevention through chemoprevention, dietary and lifestyle modifications
- early detection and removal of precursor lesions such as the adenomatous polyp.
This chapter focuses on primary prevention, and summarises advances in the knowledge and application of interventions to prevent colorectal cancer, thereby reducing the incidence of the disease.
Chapter subsections[edit source]
- Australian Institute of Health and Welfare. Cancer in Australia: an overview 2014. [Version updated 16 April 2015] Cancer series No 90. Cat. no. CAN 88. Canberra: AIHW;.
- Whiteman DC, Webb PM, Green AC, Neale RE, Fritschi L, Bain CJ, et al. Cancers in Australia in 2010 attributable to modifiable factors: introduction and overview. Aust N Z J Public Health 2015 Oct;39(5):403-7 Available from: http://www.ncbi.nlm.nih.gov/pubmed/26437722.
- Song M, Giovannucci E. Preventable Incidence and Mortality of Carcinoma Associated With Lifestyle Factors Among White Adults in the United States. JAMA Oncol 2016 Sep 1;2(9):1154-61 Available from: http://www.ncbi.nlm.nih.gov/pubmed/27196525.