Causes of cancer
Most cancers develop because of changes (mutations) in genes. A normal cell may become a cancer cell after a series of gene changes occur. Tobacco use, certain viruses, or other factors in a person’s lifestyle or environment can cause such changes in certain types of cells.
Some gene changes that increase the risk of cancer are passed from parent to child. These changes are present at birth in all cells of the body.
It is uncommon for cancer to run in a family. However, certain types of cancer do occur more often in some families than in the rest of the population. For example, melanoma and cancers of the breast, ovary, prostate, and colon sometimes run in families. Several cases of the same cancer type in a family may be linked to inherited gene changes, which may increase the chance of developing cancers. (MedicineNet)
Cancer is a complex group of diseases with many possible causes. Learn more about the known causes of cancer, including genetic factors; lifestyle factors such as tobacco use, diet, and physical activity; certain types of infections; and environmental exposures to different types of chemicals and radiation. (American Cancer Society)
Genetics and Cancer
Some types of cancer run in certain families, but most cancers are not clearly linked to the genes we inherit from our parents. In this section you can learn more about the complex links between genes and cancer, as well as genetic testing and how it is used.
Tobacco and Cancer
In this section you can get information on cigarette, cigar, and smokeless tobacco use, and learn how it affects different groups of people.
Diet and Physical Activity
Get the facts on how diet, physical activity, excess body weight, and alcohol use may affect your risk of cancer.
Sun and UV Exposure
In this section you can learn more about the link between too much sun exposure and cancer.
Radiation Exposure and Cancer Risk
Learn about the different types of radiation exposure and how it might affect cancer risk.
Learn about some of the environmental causes of cancer that may lurk in our homes, at work, in pollution, and even in some medical tests and treatments. You can also learn how some types of infections are linked to cancer.
A large number of cancers are preventable and all cancers caused by cigarette smoking and heavy use of alcohol could be prevented. Close to one third of cancer cases that occur in developed countries like the US are related to being overweight, obese, inactive (sedentary) or having poor nutrition. These are all potentially preventable! Learn about the causes of cancer.