Oral Cancer: A Patient Guide from the National Cancer Institute

Oral cancer refers to cancer that develops in any part of the mouth (oral cavity) or the oropharynx — the back of the throat, including the soft palate, the side and back walls of the throat, the tonsils, and the back third of the tongue.

The most common type of oral cancer is squamous cell carcinoma, which starts in the thin, flat cells lining the inside of the mouth and throat. Less common types include salivary gland cancers, lymphomas, and melanomas.

According to the National Cancer Institute (NCI), oral and oropharyngeal cancers together are the 8th most common cancer in U.S. men and a growing concern in women as well — driven in large part by the rising incidence of HPV-related oropharyngeal cancers.

• About 54,000 new cases of oral and oropharyngeal cancer are diagnosed in the U.S. each year.
• More than 11,000 Americans die from these cancers annually.
• The disease is about twice as common in men as in women.
• The average age at diagnosis is 63, but cases in younger adults — especially HPV-related oropharyngeal cancers — are rising.

Most people who develop oral cancer have one or more known risk factors. However, oral cancer can also develop in people with none of these risk factors.

Tobacco use

Tobacco use of any kind — including cigarettes, cigars, pipes, smokeless tobacco (chewing tobacco, snuff, dip), and exposure to secondhand smoke — substantially raises the risk of oral cancer. About 75% of people diagnosed with oral cavity cancer are tobacco users.

Heavy alcohol use

Heavy alcohol use is independently associated with oral cancer, and the combination of tobacco and heavy alcohol use multiplies risk far more than either factor alone.

HPV infection

Human papillomavirus (HPV) infection — particularly HPV type 16 — is strongly associated with oropharyngeal cancers, especially those at the base of the tongue and tonsils. HPV-related oropharyngeal cancers have been increasing in the U.S. for decades, especially among middle-aged men. HPV-related oropharyngeal cancer generally has better treatment outcomes than tobacco-related disease.

Sun exposure

Prolonged sun exposure raises the risk of cancers of the lip, particularly the lower lip. Lip cancer is most common in outdoor workers and people with fair skin.

Diet

A diet low in fruits and vegetables has been associated with a higher risk of oral cancer.

Age and sex

Most oral cancers occur in people over 40. The disease is about twice as common in men as in women.

Many of the signs and symptoms of oral cancer are similar to those of other, less serious problems. However, when these symptoms last for more than 2 weeks, they should be evaluated by a dentist or physician.

• A sore in the mouth or on the lip that does not heal
• A lump or thickening in the cheek
• A white or red patch on the gums, tongue, tonsil, or lining of the mouth
• A persistent sore throat or feeling that something is caught in the throat
• Difficulty chewing or swallowing
• Difficulty moving the jaw or tongue
• Numbness of the tongue or other area of the mouth
• Swelling of the jaw that causes dentures to fit poorly or become uncomfortable
• Loosening of the teeth or pain around the teeth or jaw
• Voice changes
• A lump or mass in the neck
• Weight loss
• Persistent bad breath

A routine dental visit typically includes a brief oral cancer screening. The dentist examines the lips, cheeks, gums, tongue, floor of the mouth, and back of the throat — and feels for unusual lumps in the neck and under the jaw. The exam takes only a few minutes and is painless.

There is no formally recommended national screening program for oral cancer in average-risk adults. However, the American Dental Association supports annual oral cancer screening as part of a regular dental exam — and screening is one of the most effective tools we have for early detection.

If a suspicious area is found, the next step is usually a biopsy — a small sample of tissue is removed and examined under a microscope. If cancer is confirmed, imaging tests (CT, MRI, PET) are used to determine whether and where the cancer has spread.

Treatment depends on the location, size, stage, and type of cancer, as well as the patient's overall health.

Surgery

Surgical removal of the tumor and surrounding tissue is the most common first-line treatment for oral cavity cancers. Reconstructive surgery may follow to restore form and function.

Radiation therapy

High-energy radiation is often used after surgery to destroy remaining cancer cells, or as a primary treatment for tumors that are difficult to remove surgically. Intensity-modulated radiation therapy (IMRT) allows precise targeting to minimize damage to surrounding healthy tissue.

Chemotherapy

Drug therapy is often used in combination with radiation for more advanced cancers.

Targeted therapy and immunotherapy

Newer treatments such as cetuximab (a targeted therapy) and pembrolizumab and nivolumab (immunotherapy drugs) are now approved for certain advanced or recurrent oral and oropharyngeal cancers.

When oral cancer is detected and treated at its earliest stages (Stage I), the 5-year relative survival rate exceeds 80%. Once the disease has spread to nearby lymph nodes or distant sites, survival rates drop sharply. This is why early detection matters so much.

The single most effective way to prevent oral cancer is to avoid tobacco in all forms. Limiting alcohol consumption, using sunscreen lip balm outdoors, eating a diet rich in fruits and vegetables, and receiving the HPV vaccine (recommended through age 26, and shared decision-making through age 45) all substantially lower risk.

Oral cancer is more common than many people realize, but it is also one of the most preventable and detectable cancers when caught early. A 5-minute oral cancer screening at a regular dental visit can save a life.

This article is adapted from public-domain content published by the U.S. National Cancer Institute (NCI) and the National Institute of Dental and Craniofacial Research (NIDCR).