Screening for cancer of the aerodigestive tract.
In the United States, cancer of the oral cavity is the only region of the aerodigestive tract that lends itself to routine screening of the asymptomatic population older than 50 years. Although the incidence and mortality rate for oral cancer is nearly double that of cancer of the cervix (30,300 versus 13,500 and 7950 versus 4400, respectively), conducting a pelvic examination and Pap smear appears more acceptable than looking in the mouth. The inspection of the oral cavity should be part of every physical examination in the dentist's or the physician's office, particularly in patients older than 50 years who are heavy users of tobacco and alcohol. Ninety percent of all squamous cell cancers arise from the floor of the mouth, the ventrolateral aspect of the tongue, and the soft palate complex. The detection rate is increased from approximately 1 per 1000 in asymptomatic individuals older than 50 years to 1 per 200 in high-risk smokers and drinkers and to 1 in 7 for individuals once treated for oral cancer. Screening detects earlier stage cancers, for which treatment results in higher survival rates. While no randomized screening trials with a mortality end-point have been conducted (or are likely), there is evidence that population-based case-fatality rates are lower in races treated with earlier stages of oral cancer. This evidence is of little solace when the majority of patients are diagnosed with advanced disease when symptoms appear, rather than through screening at an earlier stage when asymptomatic. In one study, 94% of patients with oral cancer were seen by a doctor within the previous year. The average oral cancer patient had 10.7 physician encounters within 3 years of the diagnosis. In the United States, the early detection of cancers of the larynx and esophagus should be based upon early symptoms rather than on screening. A routine oral screening examination should be a part of every physical examination by a doctor or a dentist. It will detect earlier cancers and save lives.