CA 19-9 and CA 125 levels in the sera of normal blood donors in relation to smoking history.

CA 19-9 and CA 125 serum levels were evaluated among smoking and nonsmoking healthy blood donors. Smoking did not elevate mean levels of either CA 19-9 or CA 125 in the sera of 496 of these blood donors from Philadelphia, PA. Mean CA 19-9 levels were slightly higher among females than among males. Among smokers there was a trend toward slightly increasing CA 19-9 serum levels with increased age, which was significant among the male donors. Trends toward slightly decreased mean serum levels of CA 125 among smokers were of borderline significance. Serum CA 19-9 and CA 125 levels in none of these donor subpopulations was elevated compared to levels reported by others for gastrointestinal or ovarian carcinoma patients, respectively. Therefore, smoking status should not interfere with use of either the CA 19-9 or CA 125 assays for diagnostic or monitoring applications.