Role of biology and prevention in aerodigestive tract cancers.

Primary prevention aimed at smoking control and chemoprevention for high-risk persons or patients at risk for a second cancer provide strong potential for cancer prevention and control of aerodigestive cancers. The National Cancer Institute (NCI) has a major effort to build this area of research. The Third Upper Aerodigestive Tract Cancer Task Force Workshop, held in 1989 under the auspices of the National Cancer Institute's Organ System Program, reviewed the opportunities for chemoprevention research on aerodigestive epithelial cancers such as the regulation of growth and differentiation in normal and malignant cells. The chemoprevention program's drug development effort is evaluating several promising candidate agents for future clinical testing and the NCI clinical intervention program is supporting several trials of selected chemoprevention agents with demonstrated potential for inhibiting cancers of the lung, bronchus, oral cavity, and esophagus. Of special interest to this program is the assessment of beta-carotene, retinol and related synthetic retinoids, and several vitamin and mineral combinations under study in high-risk international populations. Chemoprevention in the medical setting is a major focus of NCI's Community Oncology Program (CCOP), a network designed not only to increase accrual of patients to trials but also to speed adoption of state-of-the-art therapies. Public health strategies are directed toward control of exposure to tobacco. The focal point for these activities is NCI's Smoking, Tobacco, and Cancer Program (STCP). STCP smoking cessation efforts are targeted at specific populations that are at greater risk for developing cancer including youth, minority and ethnic groups, women, smokeless tobacco users, and heavy smokers. Two of the world's largest controlled intervention trials conducted by the STCP are underway: the Community Intervention Trial for Smoking Cessation (COMMITT), which focuses on 6.5 million heavy smokers in 11 pairs of matched communities in North America, and the American Stop Smoking Intervention Study (ASSIST), a coalition model designed to reach millions of Americans through existing health promoting systems.