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Chemoprevention of head and neck cancer.

Cancer of the aerodigestive tract is associated with great morbidity and mortality in the United States and worldwide. Despite substantial improvements in the delivery of cytotoxic drugs and ionizing radiation therapies, which have resulted in better treatment outcomes, mortality from head and neck malignancies has changed minimally over the last fifty years. Furthermore, the long-term untoward consequences of treatment are significant. Based on this, prevention emerges as a very attractive strategy. Primary prevention through the avoidance of major risk factors, (eg, smoking and ethanol consumption) would result in substantial gains. Unfortunately, behavioral modification (eg, smoking cessation) is not easy to achieve and/or sustain, and even when attained, the carcinogenic risk does not seem to return to that of an individual who never smoked. Chemoprevention is a modality in which compounds are administered singly or in combination to individuals at increased carcinogenic risk in order to halt, prevent, or delay the onset of invasive cancer. This article will review the current status of chemoprevention of the upper aerodigestive tract (UADT), including its biologic basis, clinical models to test for chemopreventive efficacy, and some of the promising strategies that have completed clinical testing or are currently under investigation. Future prospects in the field will also be discussed.