Tobacco smoke contains over 60 chemicals known to cause cancer. Certain chemicals in tobacco smoke damage an important gene called p53. The p53 gene is found in the nucleus of every cell in the human body and its main role is to prevent cancer cells evolving. Cigarette smoke is the main cause of p53 mutations in lung cancer.
Approximately one fifth of all cancer deaths in Australia are due to smoking.
Lung cancer is the most common form of cancer caused by smoking. More than 80% of cases of lung cancer are due to smoking.
Smoking also causes cancer of the tongue, mouth, throat, nose, nasal sinus, voice box, oesophagus pancreas, stomach, liver, kidney, bladder, ureter, bowel, cervix, ovary, and bone marrow (myeloid leukemia).
After you quit, your risk of cancer will be lower than the risk for those who continue to smoke. For some types of cancer your risk returns to that of someone who has never smoked.