Risk Factors for Oral Cavity and Oropharyngeal Cancers

A risk factor is anything that increases a person’s chance of getting a disease such as cancer. Different cancers have different risk factors. Some risk factors, like smoking, can be changed. Others, like a person’s age or family history, can’t be changed.

But risk factors don't tell us everything. Having a risk factor, or even many, does not mean that a person will get the disease. And many people who get the disease have few or no known risk factors.

Oral cavity and oropharyngeal cancers are often grouped with other cancers in the head and neck area. These cancers often have many of the same risk factors listed below.

Tobacco and alcohol use

Tobacco use is one of the strongest risk factors for head and neck cancers, including oral cavity and oropharyngeal cancer. The risk for these cancers is much higher in people who smoke than in people who don't. Most people with these cancers have a history of smoking or other tobacco exposure, like chewing tobacco. The more you smoke, the greater your risk. Smoke from cigarettes, pipes, and cigars all increase your risk of getting these cancers. Some studies have also found that long-term exposure to secondhand smoke might increase the risk of these cancers, but more research is needed to confirm this. Pipe smoking is linked to a very high risk for cancer in the part of the lips that touch the pipe stem.

Oral tobacco products (snuff, dip, spit, chew, or dissolvable tobacco) are linked with cancers of the cheek, gums, and inner surface of the lips. Using oral tobacco products for a long time is linked to a very high risk. These products also cause gum disease, destruction of the bone sockets around teeth, and tooth loss.

When diagnosed with oral cavity or oropharyngeal cancer, it's important for people who smoke or use oral tobacco, to quit smoking and quit all oral tobacco products. People who continue to smoke while getting cancer treatment can have trouble with wound healing, more side effects from radiation therapy or chemotherapy, a higher risk of infection, and worse outcomes. Also, continuing to smoke and use oral tobacco products after cancer treatment, greatly increases the risk of developing a second cancer in the mouth, throat, larynx (voice box), lung and other organs.

If you are thinking about quitting tobacco and need help, call the American Cancer Society at 1-800-227-2345. A tobacco cessation and counseling program can help increase your chances of quitting for good. See How to Quit Smoking or Smokeless Tobacco for more information.

Drinking alcohol increases the risk of developing oral cavity and oropharyngeal cancers. Heavy drinkers have a higher risk than light drinkers.

Smoking and drinking alcohol together multiplies the risk of these cancers. The risk of these cancers in people who drink and smoke heavily is about 30 times higher than the risk in people who don’t smoke or drink.

Betel quid and gutka

In Southeast Asia, South Asia, and certain other areas of the world, many people chew betel quid, which is made up of areca nut (betel nut), spices, lime, and other ingredients. Many people in these areas also chew gutka, a mixture of betel quid and tobacco. People who chew betel quid or gutka have an increased risk of cancer of the mouth.

Human papillomavirus (HPV) infection

Human papillomavirus (HPV) is a group of more than 150 types of viruses. They're called papillomaviruses because some of them cause a type of growth commonly called a papilloma or wart.

Infection with certain types of HPV can cause some forms of cancer, including cancers of the penis, cervix, vulva, vagina, anus, mouth, and throat. HPV type 16 (HPV16) is the type most often linked to cancer of the oropharynx, especially those in the tonsil and base of tongue. HPV DNA (a sign of HPV infection) is found in about 2 out of 3 oropharyngeal cancers and in a much smaller portion of oral cavity cancers.

The number of oropharyngeal cancers linked to HPV has risen greatly over the past few decades. These cancers are becoming more common in younger people who have a history of multiple sex partners (including oral sex) and no history of alcohol abuse or tobacco use. Oropharyngeal cancers linked to HPV infection tend to have better outcomes (prognoses) than tumors not caused by HPV because chemotherapy and radiation treatments work better for these cancers. This improvement in outcome however is not seen in people with HPV-related oropharyngeal cancers who also smoke.  

See HPV (human papillomavirus) to learn more about HPV and vaccines to prevent HPV infection.

Sex

Oral cavity and oropharyngeal cancers are twice as common in men than in women. This might be because men have been more likely to use tobacco and alcohol in the past. HPV-related oropharyngeal cancers are also seen more often in men.

Excess body weight

Having too much body weight appears to increase the risk of cancers of the oropharynx and larynx.  Eating more plant-based foods, such as nonstarchy vegetables and whole fruit, might help people lose weight as well as reduce their risk of oropharyngeal and laryngeal cancer from poor nutrition.

Age

Cancers of the oral cavity and oropharynx usually take many years to develop, so they're not common in young people. Most patients with these cancers are older than 55 when the cancers are first found. HPV-linked cancers tend to be diagnosed in people younger than 50.

Ultraviolet (UV) light

Sunlight is the main source of UV light for most people. Cancers of the lip are more common in people who have outdoor jobs where they are exposed to sunlight for long periods of time.

Poor nutrition

Several studies have found that a diet low in fruits and vegetables is linked with an increased risk of cancers of the oral cavity and oropharynx.

Genetic syndromes

People with syndromes caused by inherited defects (mutations) in certain genes have a very high risk of mouth and middle throat cancer.

• Fanconi anemia: People with this syndrome often have blood problems at an early age, which may lead to leukemia or myelodysplastic syndrome. They also have a very high risk of cancers of the mouth and throat.
• Dyskeratosis congenita: This is a genetic syndrome that can cause aplastic anemia, skin rashes, and abnormal fingernails and toenails. People with this syndrome also have a very high risk of developing head and neck cancers, especially of the mouth and throat, at a young age.

Unproven or controversial risk factors

Mouthwash

Some studies have suggested that mouthwash with a high alcohol content might be linked to a higher risk of oral and oropharyngeal cancers. But recent research has questioned these results. Studying this possible link is complicated by the fact that people who smoke and frequent drinkers (who already have an increased risk of these cancers) are more likely to use mouthwash than people who neither smoke nor drink.

Irritation from dentures

It's been suggested that long-term irritation of the lining of the mouth caused by poorly fitting dentures is a risk factor for oral cancer. But many studies have found no increased risk in denture wearers overall.

Poorly fitting dentures can tend to trap agents that have been proven to cause oral cancer, such as alcohol and tobacco particles, so denture wearers should have them checked by a dentist regularly to ensure a good fit. All denture wearers should remove their dentures at night and clean and rinse them thoroughly every day.

Oral health

Studies have suggested the overall health of the mouth, teeth, and gums may impact oral cavity and oropharyngeal cancer risk because of changes in the normal bacteria in the mouth. Poor oral hygiene, which can lead to tooth loss, may also be linked to these cancers. Overall survival may also be affected. More research is needed, but regular dental visits, as well as brushing and flossing, may lessen these risks and have many other health benefits, too.