Colorectal cancer: The facts

Colorectal cancer is the most common cancer affecting both men and women in Australia.1,2

  • 16 000 people were diagnosed in 2012,
  • 13% of all cancers.

Colorectal cancer is the second leading cause of cancer deaths in Australia:

  • Almost 4000 deaths in 2010 alone. 2

Between 1991 and 2010 the mortality rate from colorectal cancer fell by around 40%, the decline is attributed to earlier detection and improvements in treatments and surgical techniques.2

The natural history of colorectal cancer is well defined

Most cancers develop from adenomatous polyps occurring in the wall of the colon.3,4 These adenomas are common in ageing populations and most (19 out of 20) will not become malignant.5 However, prognostic indicators, such as a diameter greater than 10 mm, indicate those which have a greater likelihood of progressing.5 These advanced adenomas are slow growing and if treated while still on the wall of the colon a 90% survival rate is achieved.3

Early detection is critical

Most people with early stage colorectal cancer have no obvious symptoms.5 The survival rate depends on the stage of disease at diagnosis.(Table 1) Without screening only around 15% of colorectal cancer cases are detected at the earliest stage.5

Table 1: Five-year survival rates for colorectal cancer5
Cancer stage
Clinical characteristics
Five-year survival rate
Stage A
Locally contained cancer
88%
Stage B
Locally advanced cancer. No lymph node involvement
70%
Stage c
Locally advanced cancer with lymph node involvement
43%
Stage D
Metastatic disease
7%

For more information

References
  1. Australian Institute of Health and Welfare. The Australian Bowel Cancer Screening Pilot and Beyond: Final Evaluation Report. 2005. http://www.health.gov.au/internet/screening/publishing.nsf/Content/2DDFA95B20302107CA2574EB007F7408/$File/final-eval.pdf (accessed 29 January 2013).
  2. Australian Institute of Health and Welfare. Cancer in Australia an overview 2012. 2012. http://www.aihw.gov.au/publication-detail/?id=60129542359 (accessed  4 March 2013).
  3. The Cancer Council Australia and Australian Cancer Network 2005. Clinical Practice Guidelines for the Prevention, Early Detection and Management of Colorectal Cancer. 2005. http://www.nhmrc.gov.au/_files_nhmrc/publications/attachments/cp106_0.pdf (accessed 13 February 2013).
  4. Tierney RP, Ballantyne GH, Modlin IM. The adenoma to carcinoma sequence. Surg Gynecol Obstet 1990;171:81-94. [PubMed]
  5. Cancer Council Australia. National Cancer Prevention Policy Bowel (colorectal) cancer. 2012. http://wiki.cancer.org.au/prevention/Bowel_cancer (accessed 7 February 2013).