The development of molecular epidemiology to elucidate cancer risk and prognosis: a historical perspective.

Molecular epidemiology in cancer research grew from the field of chemical carcinogenesis and the use biomarkers for environmental exposures, with incorporation of principles from early pharmacogenetics. Over the years, molecular epidemiology has become extremely complex, with studies evaluating associations between cancer risk and prognosis and numerous markers of susceptibility, exposure and early effects, as well as epidemiologic factors. In this article, we review the field of molecular epidemiology from a historical perspective, commenting on current status of the field and future directions.