Biochemical epidemiology of cervical neoplasia: measuring cigarette smoke constituents in the cervix.

In preparation for an epidemiological investigation of cigarette smoking and cervical neoplasia, we studied methods of measuring cervical exposure to tobacco smoke. The measurement of cotinine in cervical flushes by radioimmunoassay proved to be highly accurate in distinguishing smokers from nonsmokers, achieving 100% sensitivity and 97% specificity. In most subjects, quantitative levels of cervical cotinine and nicotine mirrored recent smoking intensity. Some of the apparent exceptions may have resulted from metabolic/secretory traits of the subjects. If so, the biochemical measurement of smoke constituents in the cervix might prove more valuable for epidemiological studies of cervical neoplasia than data on current smoking behavior collected by interview.