Cancer, Oral Cavity and Oropharynx

Risk: The greatest risk factor for cancer in the oral cavity is tobacco use, including smokeless tobacco. Smokers and those who drink a lot of alcohol are 6 times more likely to develop oral cavity or oropharyngeal cancer than nonusers ("Detailed Guide"). Other risk factors are poor oral hygiene with bacterial irritation, poor nutrition, immunosuppressed states and human immunodeficiency virus (HIV) and acquired immune deficiency syndrome (AIDS). Individuals who work or recreate outdoors have a 30% increased risk for lip cancer ("Detailed Guide").

Risk factors for oropharyngeal cancer include tobacco use in any form, alcohol consumption, exposure to occupational health hazards (including man-made vitreous or wool fibers such as fiberglass and blown-in insulation, mustard gas, vinyl chloride polymers, isopropyl alcohol, hexavalent chromium, tannin extract, azo dyes, and aryl hydrocarbon hydroxylase), viral infections such as human papilloma virus, and genetic predisposition.

Men are nearly twice as likely to be affected as women by oral cavity and oropharyngeal cancer ("Detailed Guide").

Incidence and Prevalence: Oral cavity and oropharyngeal cancers are more common in blacks than in whites, and are generally found in individuals over the age of 35 ("Detailed Guide"). In the US in 2005 there will be 29,370 predicted new cases of oral cavity and oropharyngeal cancer, with 7,230 deaths; however, new diagnoses and mortality rates for oral cavity and oropharyngeal cancer have been falling over the last 20 years, possibly in part due to reduced tobacco use in the US ("Detailed Guide").

History: Cancer of the oral cavity and oropharynx is often painless in its early stage. Individuals may complain of irritation in the throat and usually only report pain when the cancer develops into a crater-like (ulcerated) lesion. Individuals may also report a lump in the neck that represents spread (metastasis) of the cancer from the oropharynx. Individuals may also report a change in their voice, or persistent bad breath.

Cancer of the base of the tongue is usually quite advanced when diagnosed, because in the early stages it cannot be seen and creates few, if any symptoms. In some cases, the cancer will spread quickly into the lymphatic system, and the individual may report only a lump in the neck. Later in the course of the disease, an ulcerated lesion that is several centimeters in diameter may be found. The individual usually complains of increasing pain, a sense of fullness, changes in the voice, and speech and swallowing difficulty. The pain can be severe and constant and may radiate to the neck and ears. There may be a history of cancer on the lips, inside the cheeks, on the roof of the mouth, or in the upper throat area.

Physical exam: Early stage oral cavity and oropharyngeal cancer may appear as small, apparently harmless areas of hardness or ulceration. Areas of tissue hardness (also referred to as areas of induration) or areas of ulceration usually represent tissue that is being infiltrated by a tumor. As the disease progresses, destruction of the inner lining in the back of the mouth or throat (erosion), redness or inflammation (erythema) of mucus membranes in the oropharynx, induration in normally soft throat tissues, oropharyngeal sores that do not heal (chronicity), hardening or enlargement of the nodes (lymphadenopathy), or white patches on the oropharyngeal mucosa (leukoplakia) are commonly observed. Eroded areas may appear ulcerated with irregular borders or raised edges. The individual may have enlarged, nontender lymph nodes in the neck.

In tongue cancer a grayish lesion (ulcer) in the bottom of a furrow (fissure) or on the surface of the oral tongue may be evident. Patchy areas (lesions) that can be white (leukoplakic) or pink to red (erythroplakia) may or may not be associated with the ulcer. Later in the course of the disease, the ulcer may be hard in consistency, with heaped-up (everted) edges. The floor of the ulcer may be grainy (granular) and hardened (indurated) and may bleed easily. There are often other areas of dying tissue (necrosis) on the tongue. Infiltration (metastasis) of the cancer into the lymphatic system is common in later stages, and many individuals will have enlarged nodes that are detectable by touch (palpable).

Tests: Individual cells may be scraped from the lesion and observed microscopically to determine if they are cancerous (exfoliate cytology). If exfoliate cytology indicates that the cells are cancerous or if the lesion looks suspiciously like cancer, a small piece of tissue may be taken from the lesion (incisional biopsy) and examined microscopically to determine malignancy. The lymph nodes may be biopsied if it is still unclear whether the primary oropharyngeal lesion is cancerous. In this case, the entire lymph node can be removed (excisional biopsy) and tested. Alternatively, a fine needle aspiration biopsy is an accurate technique for identifying oropharyngeal lesions that have spread to the lymph nodes. After an oropharyngeal tumor is identified as cancer, CT or MRI can determine the extent of tumor growth.