- Cancer is a leading cause of death worldwide: it accounted for 7.6 million deaths (around 13% of all deaths) in 2008.
- Lung, stomach, liver, colon and breast cancer cause the most cancer deaths each year.
- The most frequent types of cancer differ between men and women.
- About 30% of cancer deaths are due to the five leading behavioral and dietary risks: high body mass index, low fruit and vegetable intake, physical inactivity, tobacco use, alcohol use. All these cancers are often preventable.
- Infectious agents are responsible for almost 22% of cancer deaths in the developing world and 6% in industrialized countries.
- Tobacco use is the single largest preventable cause of cancer in the world causing 22% of cancer deaths. About 70% of the lung cancer burden can be attributed to smoking alone.
- Cancer arises from a change in one single cell. The change may be started by external agents or inherited genetic factors.
- About 70% of all cancer deaths in 2008 occurred in low- and middle-income countries.
- Deaths from cancer worldwide are projected to continue to rise to over 11 million in 2030.
Modifying and avoiding risk factors
More than 30% of cancer could be prevented by modifying or avoiding key risk factors, including:
- tobacco use
- being overweight or obese
- low fruit and vegetable intake
- lack of physical activity
- alcohol use
- Human papillomavirus and Hepatitis B infection
- urban air pollution
- indoor smoke from household use of solid fuels.
- Increase avoidance of the risk factors listed above.
- Vaccinate against human papilloma virus (HPV) and hepatitis B virus (HBV).
- Control occupational hazards.
- Reduce exposure to sunlight.
Cancer mortality can be reduced if cases are detected and treated early. There are two components of early detection efforts:
- Early diagnosis
- The awareness of early signs and symptoms (such as cervical, breast and oral cancers) in order to facilitate diagnosis and treatment before the disease becomes advanced.
- Early diagnosis programmes are particularly relevant in low-resource settings where the majority of patients are diagnosed in very late stages.
- The systematic application of a screening test in an asymptomatic population. It aims to identify individuals with abnormalities suggestive of a specific cancer or pre-cancer and refer them promptly for diagnosis and treatment.
- Screening programmes are especially effective for frequent cancer types that have a screening test that is cost-effective, affordable, acceptable and accessible to the majority of the population at risk.