Cancer is a leading cause of death worldwide: it accounted for 7.4 million deaths
(around 13% of all deaths) in 2004.
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.
Tobacco use is the single most important risk factor for cancer.
Cancer arises from a change in one single cell. The change may be started by external
agents and inherited genetic factors.
More than 30% of cancer deaths can be prevented.
Deaths from cancer worldwide are projected to continue rising,
with an estimated 12 million deaths in 2030.
Cancer is a generic term for a large group of diseases that can affect any part of the body. Other terms used are malignant tumours and neoplasms. One defining feature of cancer is the rapid creation of abnormal cells that grow beyond their usual boundaries, and which can then invade adjoining parts of the body and spread to other organs. This process is referred to as metastasis. Metastases are the major cause of death from cancer.