Biochemical epidemiology: uses in the study of human carcinogenesis.

The use of biochemical markers may improve the potentialities of etiologic epidemiology. Exposure markers or markers of biologically effective dose allow better exposure assessment, therefore decreasing misclassification in epidemiological studies. Markers of individual susceptibility (such as metabolic polymorphism) permit the identification of subgroups of subjects at higher risk of cancer. In general, the integration of biochemical methods and an epidemiological design is helpful in the study of the sources of interindividual variability in response to carcinogenic stimuli. We review several investigations making use of biochemical measurements in the field of cigarette-induced bladder cancer.