Biomarkers of carcinogenesis of the upper and lower airway epithelium and the role of chemoprevention

Lung as well as head and neck cancer represent an important public health p roblem worldwide, with lung cancer being the leading cause of cancer death in western countries. Although early stage disease is often curable with su rgery or radiotherapy, the majority of patients present with advanced disea se in which despite advances in combined modality therapy the outcomes have not dramatically improved. Furthermore, patients cured of their initial ea rly stage lung or head and neck carcinoma are at high risk for development of second primary tumors, which pose the main threat to their survival. An alternative approach in reducing the incidence and thus mortality of these cancers is chemoprevention, the use of agents to reverse, halt or delay car cinogenesis. The carcinogenesis process in lung and head and neck cancer re sults from a dysregulation of cellular proliferation, differentiation and c ell death resulting from field-wide exposure of the upper and lower airway track to tobacco smoking. This review article presents main data regarding the actual understanding of lung and head and neck carcinogenesis, as well as results of major chemoprevention trials in this field.