Causes of cancer

We do not know all of the risks and causes of cancer. However, there are a number of chemical, physical and biological agents that have been shown to trigger the mistakes in the cell blueprint that cause cancer. These are called carcinogens and include tobacco, ultraviolet radiation and asbestos.

A number of cancers share risk factors:

  • Around 1 in 8 cancer cases, and 1 in 5 cancer deaths, are due to smoking [1];
  • Lung cancer is the most common cancer caused by smoking, and accounts for nearly 10 per cent of all new cancer cases in Tasmania, and almost 20 per cent of all cancer deaths in Tasmania. [2]
  • About 3 per cent of cancers are related to alcohol consumption [3];
  • Many cancers occur as a direct result of dietary influences, from infectious agents or exposure to radiation (especially skin cancers from ultraviolet radiation);
  • Some cancers result from inherited ‘faulty’ genes;
  • Some cancers are the result of occupational exposure to carcinogens (cancer causing agents) such as asbestos, diesel engine exhaust and benzene;
  • Cancer is NOT caused by injury or stress.
    [1] Pandeya N. et al. 2015. Cancers in Australia in 2010 attributable to tobacco smoke Aust NZ J Public Health; 39:464-70
    [2] Cancer in Tasmania: Incidence and Mortality 2013. Menzies Institute for Medical Research Tasmania, Hobart, March 2016.
    [3] Whiteman, al, 2015. Cancers in Australia in 2010 attributable to modifiable factors: summary and conclusions, Aust NZ J Public Health; 39:477-84

It is important to note that not all cancers are associated to the risk factors mentioned above. Cancer can sometimes develop without any specific causes.


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