Lung cancer: Premalignant biology and medical prevention.

Lung cancer (both adenocarcinoma and squamous cell) progress through a series of pre-malignant histologic changes before the development of invasive disease. Each of these carcinogenic cascades is defined by genetic and epigenetic alterations in pulmonary epithelial cells. Additionally, alterations in the immune response, progenitor cell function, mutational burden, and microenvironmental mediated survival of mutated clones contribute to the risk of pre-malignant lesions progressing to cancer. Medical preventions studies have been completed and current and future trials are informed by the improved understanding of pre-malignancy. This will lead to precision chemoprevention trials based on lesional biology and histologic characteristics.