Oral cancer

Oral cancer is part of a group of cancers called head and neck cancers. Oral cancer can develop in any part of the oral cavity or oropharynx. Most oral cancers begin in the tongue and in the floor of the mouth. Almost all oral cancers begin in the flat cells (squamous cells) that cover the surfaces of the mouth, tongue, and lips. These cancers are called squamous cell carcinomas.

When oral cancer spreads (metastasizes), it usually travels through the lymphatic system. Cancer cells that enter the lymphatic system are carried along by lymph, a clear, watery fluid. The cancer cells often appear first in nearby lymph nodes in the neck.

Cancer cells can also spread to other parts of the neck, the lungs, and other parts of the body. When this happens, the new tumor has the same kind of abnormal cells as the primary tumor. For example, if oral cancer spreads to the lungs, the cancer cells in the lungs are actually oral cancer cells. The disease is metastatic oral cancer, not lung cancer. It is treated as oral cancer, not lung cancer. Doctors sometimes call the new tumor "distant" or metastatic disease.

Oral cancer: Who's at risk?

Doctors cannot always explain why one person develops oral cancer and another does not. However, we do know that this disease is not contagious. You cannot "catch" oral cancer from another person.

Research has shown that people with certain risk factors are more likely than others to develop oral cancer. A risk factor is anything that increases your chance of developing a disease.

The following are risk factors for oral cancer:

• Tobacco: Tobacco use accounts for most oral cancers. Smoking cigarettes, cigars, or pipes; using chewing tobacco; and dipping snuff are all linked to oral cancer. The use of other tobacco products (such as bidis and kreteks) may also increase the risk of oral cancer. Heavy smokers who use tobacco for a long time are most at risk. The risk is even higher for tobacco users who drink alcohol heavily. In fact, three out of four oral cancers occur in people who use alcohol, tobacco, or both alcohol and tobacco.
• Alcohol: People who drink alcohol are more likely to develop oral cancer than people who don't drink. The risk increases with the amount of alcohol that a person consumes. The risk increases even more if the person both drinks alcohol and uses tobacco.
• Sun: Cancer of the lip can be caused by exposure to the sun. Using a lotion or lip balm that has a sunscreen can reduce the risk. Wearing a hat with a brim can also block the sun's harmful rays. The risk of cancer of the lip increases if the person also smokes.
• A personal history of head and neck cancer: People who have had head and neck cancer are at increased risk of developing another primary head and neck cancer. Smoking increases this risk.

Quitting tobacco reduces the risk of oral cancer. Also, quitting reduces the chance that a person with oral cancer will get a second cancer in the head and neck region. People who stop smoking can also reduce their risk of cancer of the lung, larynx, mouth, pancreas, bladder, and esophagus. There are many resources to help smokers quit: The Cancer Information Service at 1-800-4-CANCER can talk with callers about ways to quit smoking and about groups that offer help to smokers who want to quit. Groups offer counseling in person or by telephone. Also, your doctor or dentist can help you find a local smoking cessation program. Your doctor can tell you about medicine (bupropion) or about nicotine replacement therapy, which comes as a patch, gum, lozenges, nasal spray, or inhaler. The "National Cancer Institute Information Resources" section has information about the Federal Government's smoking cessation Web site, http://www.smokefree.gov. For additional information, please read Smoking and Quitting Smoking.

Some studies suggest that not eating enough fruits and vegetables may increase the chance of getting oral cancer. Scientists also are studying whether infections with certain viruses (such as the human papillomavirus) are linked to oral cancer.

If you think you may be at risk, you should discuss this concern with your doctor or dentist. You may want to ask about an appropriate schedule for checkups. Your health care team will probably tell you that not using tobacco and limiting your use of alcohol are the most important things you can do to prevent oral cancers. Also, if you spend a lot of time in the sun, using a lip balm that contains sunscreen and wearing a hat with a brim will help protect your lips.