Oral Cancer Health Article

Definition

Oral cancer refers to malignancies in the oral cavity (mouth) and the oropharynx. The oral cavity includes the lips, buccal mucosa (lining of the lips and cheeks), the hard palate, floor of the mouth, teeth, front two-thirds of the tongue, and gingiva (gums). The oropharynx includes the tonsils, soft palate, back third of the tongue, and the back of the throat.

Description

In the United States, oral cancer is diagnosed in approximately 30,000 patients each year and is responsible for about 8,000 deaths. Oral cancer is the sixth most frequently occurring cancer, and the most common sites of oral cavity cancers are the floor of the mouth and the tongue. In the oropharynx the most common sites of cancerous tumors are the tonsils and base of the tongue.

The economic and social impact of this disease is great. Oral cancer may result in serious long-term disabilities such as loss of speech, hearing, salivary, and chewing functions, as well as pain and disfigurement resulting from head and neck surgery.

Causes and symptoms

Nearly three-quarters of all oral cancers are related to tobacco use—either cigarette, pipe, or cigar smoking, or the use of smokeless tobacco products such as snuff. Tobacco-specific nitrosamines are the carcinogens (cancer-causing substances) implicated in the development of oral cancers. Chronic alcohol consumption is linked to oral cancers, and the use of alcohol and tobacco together poses a greater risk than using either one alone.

Exposure to asbestos or radiation increases the risk of developing oral cancers, and exposure to sunlight is a risk factor for cancer of the lips. A high-fat diet that is also low in fruits, vegetables, and other sources of vitamins A and C has been linked to development of oral cancers.

Age, gender, and race affect the risk of developing oral cancers. Oral cancer usually occurs among older adults because they have longer exposure to lifestyle and environmental risk factors. Oral cancer occurs 2.5 times more often in males than females, and blacks are affected more often than whites. The higher rate of oral cancer among black men is attributed to lifestyle, such as nutritional status, tobacco, and alcohol use, rather than genetic differences. Recent research on tobacco and alcohol use, however, has demonstrated comparable rates of oral cancer among blacks and whites.

The signs and symptoms of oral cancer depend upon the site of the tumor. Certain types of lesions in the oral cavity have the potential to become cancerous. Leukoplakias (white lesions) and erythroplakia (red lesions) that do not resolve within two weeks should be evaluated by a healthcare professional. Other possible signs or symptoms include:

• sore throat, hoarseness, or sensation that something is caught in the throat
• lump or thickening in the oral cavity
• difficulty chewing, eating, or swallowing
• difficulty moving the tongue or jaw
• numbness, weakness, or altered sensation in the mouth or tongue
• swelling of the jaw, mouth, or tongue
• changes in hearing, smell, or taste
• changes in the fit or feel of dentures or dental appliances
• abnormal odor or discharge from nose, ears, or mouth
• lesions, sores, or thickened patches that do not readily heal or resolve

Diagnosis

An examination to screen for oral cancer may be made by a physician, dentist, or dental hygienist. Though regular self-examination—with attention to inspection for lumps, thickenings, whitish patches, or sores—may detect some oral cancers, it is not a substitute for a thorough professional examination. An oral examination, performed by a physician or dentist using a mirror and lights, identifies abnormalities in the oral cavity. The physician will also palpate the throat, neck, and head for lumps or thickenings. X rays of the mouth, performed by a radiological technologist, may be used to examine suspicious areas.

When an abnormal area is detected in the oral cavity, the definitive diagnostic technique is biopsy— removal of all or part of the suspicious area for examination under the microscope by a pathologist. Biopsy is usually performed by an oral surgeon or an ear, nose, and throat specialist, also known as an otolaryngologist. Since squamous cells line the oral cavity, nearly all oral cancers are squamous cell carcinomas.