Cancer is a leading cause of death worldwide. According to the World Health Organization, from a total of 58 million deaths worldwide in 2005, cancer accounts for 7,6 million (or 13%) of all deaths. The main types of cancer leading to overall cancer mortality are:
- lung (1,3 million deaths/year);
- Stomach (almost 1 million deaths/year);
- Liver (662 000 deaths/year);
- Colon (655 000 deaths/year) and
- Breast (502 000 deaths/year).