- Risk Factors
- Lowering Risk
Cancer prevention is action taken to lower the chance of getting cancer. By preventing cancer, the number of new cases of cancer in a group or population is lowered. Hopefully, this will lower the number of deaths caused by cancer.
To prevent new cancers from starting, scientists look at risk factors and protective factors. Anything that increases your chance of developing cancer is called a cancer risk factor; anything that decreases your chance of developing cancer is called a cancer protective factor.
Some risk factors for cancer can be avoided, but many cannot. For example, both smoking and inheriting certain genes are risk factors for some types of cancer, but only smoking can be avoided. Regular exercise and a healthy diet may be protective factors for some types of cancer. Avoiding risk factors and increasing protective factors may lower your risk, but it does not mean that you will not get cancer.
Different ways to prevent cancer are being studied, including:
- Changing lifestyle or eating habits.
- Avoiding things known to cause cancer.
- Taking medicines to treat a precancerous condition or to keep cancer from starting.
The liver is one of the largest organs in the body. It has four lobes and fills the upper right side of the abdomen inside the rib cage. The liver has many important functions, including:
- Filtering harmful substances from the blood so they can be passed from the body in stools and urine.
- Making bile to help digest fats from food.
- Storing glycogen (sugar), which the body uses for energy.
Liver cancer is the fourth most common cancer in the world, but is uncommon in the United States. In the United States, men, especially Chinese American men, have an increased risk of developing liver cancer. People are usually older than 40 years when they develop this cancer.
Finding and treating liver cancer early may prevent death from liver cancer. There is no routine effective screening test for liver cancer. See the PDQ summary on Liver (Hepatocellular) Cancer Screening for more information.
Anything that increases the chance of getting a disease is called a risk factor. Having a risk factor does not mean that you will get cancer; not having risk factors doesn't meant that you will not get cancer. Most people with a certain risk factor for cancer do not usually get the disease. Talk to your doctor or other health care professional about cancer prevention methods that might help you.The following risk factors may increase the risk of liver cancer:Hepatitis B and C
Having chronic hepatitis B or chronic hepatitis C increases the risk of developing liver cancer. The risk is even greater for people with both hepatitis B and C. Also, the longer the hepatitis infection lasts (especially hepatitis C), the greater the risk.Cirrhosis
The risk of developing liver cancer is increased for people who have cirrhosis, a disease in which healthy liver tissue is replaced by scar tissue. The scar tissue blocks the flow of blood through the liver and keeps it from working as it should. Chronic alcoholism and chronic hepatitis C are the most common causes of cirrhosis.Aflatoxin
The risk of developing liver cancer may be increased by eating foods that contain aflatoxin (poison from a fungus that can grow on foods, such as grains and nuts, that have not been stored properly).
Preventing hepatitis B infection (by being vaccinated for hepatitis B) has been shown to lower the risk of liver cancer in children. It is not yet known if it lowers the risk in adults.Cancer prevention clinical trials are used to study ways to prevent cancer.
Cancer prevention clinical trials are used to study ways to lower the risk of developing certain types of cancer. Some cancer prevention trials are conducted with healthy people who have not had cancer but who have an increased risk for cancer. Other prevention trials are conducted with people who have had cancer and are trying to prevent another cancer of the same type or to lower their chance of developing a new type of cancer. Other trials are done with healthy volunteers who are not known to have any risk factors for cancer.
The purpose of some cancer prevention clinical trials is to find out whether actions people take can prevent cancer. These may include eating fruits and vegetables, exercising, quitting smoking, or taking certain medicines, vitamins, minerals, or food supplements.New ways to prevent liver cancer are being studied in clinical trials.
Clinical trials are taking place in many parts of the country. Information about clinical trials can be found in the Clinical Trials section of the NCI Web site. Check NCI's PDQ Cancer Clinical Trials Registry for liver cancer prevention trials that are now accepting patients.