Source: National Cancer Institute Research, www.cancer.gov
Cancerprevention 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:
See the following PDQ summaries for information about screening, diagnosis, and treatment of oral cancer:
Oral cancer may form in any of three main areas:
Most oral cancers start in squamous cells (thin, flat cells) that line the lips, oral cavity, and oropharynx. Cancer that forms in squamous cells is called squamous cell carcinoma. Squamous cell carcinoma can form from lesions on the mucous membranes (the lining of the mouth and throat). These lesions include leukoplakia (an abnormal white patch of cells) and erythroplakia (an abnormal red patch of cells).
In Western countries, such as the United States, the most common areas for oral cancer are the tongue and the floor of the mouth.
Men are more than twice as likely as women to have oral cancer and die from it.
Avoiding cancerrisk factors may help prevent certain cancers. Risk factors include smoking, being overweight, and not getting enough exercise. Increasing protective factors such as quitting smoking, eating a healthy diet, and exercising may also help prevent some cancers. Talk to your doctor or other health care professional about how you might lower your risk of cancer.
Using tobacco is the leading cause of oral cancer.
All forms of tobacco, including cigarettes, pipes, cigars, and chewing (smokeless) tobacco, can cause oral cancer. For cigarette smokers, the risk of oral cancer increases with the number of cigarettes smoked per day. Tobacco use is most likely to cause oral cancer in the floor of the mouth, but also causes cancer in other parts of mouth and throat.
The risk of oral cancer is greater in people who use both tobacco and alcohol than it is in people who use only tobacco or only alcohol.
Tobacco users who have had oral cancer may develop second cancers in the oral cavity or nearby areas. These areas include the nose, throat, vocal cords, esophagus, and trachea (windpipe). This is because the oral cavity and nearby areas have been exposed to the harmful substances in tobacco, and new cancers may form over time.
Using alcohol is a major risk factor for oral cancer.
The risk of oral cancer increases with the number of alcoholic drinks consumed per day. The risk of oral cancer is about twice as high in people who have 3 to 4 alcoholic drinks per day compared to those who don't drink alcohol.
The risk of oral cancer is higher in people who use both alcohol and tobacco than it is in people who use only alcohol or only tobacco.
Being infected with a certain type of HPV virus, especially HPV type 16, increases the risk of oral cancer. HPV infection is spread mainly through sexual contact. People who have many oral sex partners have a higher risk of HPV infection. The number of cases of oral cancer caused by HPV infection is small but increasing.
There does not appear to be a higher rate of oral HPV infection in sexual partners of people with HPV-related oropharyngeal cancer.
Being exposed to sunlight may increase the risk of lip cancer. Lip cancer occurs most often on the lower lip.
Studies have shown that when people stop smoking cigarettes, their risk of oral cancer decreases by one-half (50%) within 5 years. Within 10 years of quitting, their risk of oral cancer is the same as for a person who never smoked cigarettes.
Certain risk factors, such as drinking alcohol, HPV infection, and sun exposure, increase the risk of oral cancer. It may seem that by avoiding these risk factors, the chance of having oral cancer would decrease, but that has not been proven.
Cancer preventionclinical trials are used to study ways to lower the risk of certain types of cancer. Some cancer prevention trials are done with healthy people who have not had cancer but who have an increased risk for cancer. Other prevention trials are done 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.
Chemoprevention is the use of drugs, vitamins, or other agents to prevent or delay the growth of cancer. One study found no decrease in the risk of oral cancer in male smokers who took vitamin E and beta carotene supplements (pills).
Other studies of chemoprevention are being done in patients at high risk of oral cancer. This includes patients with lesions on the mucous membranes, which may become cancer, and patients with a history of oral cancer.
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 list of cancer clinical trials for lip and oral cavity cancer prevention trials and oropharyngeal cancer prevention trials that are now accepting patients.