Cytokeratin fragment 19 (CYFRA 21-1) in healthy smokers

Two hundred and ninety-three normal female non-smokers, 268 normal male non -smokers, and 224 normal male smokers were included in our comparative Stud y to determine possible effect of smoking on the serum levels of cytokerati n fragment 19 (CYFRA 21-1). Immunoradiometric assay (IRMA) was used, and th e results revealed that the mean +/- SD CYFRA 21-1 levels in the 293 normal female non-mokers, 268 normal male non-smokers, and 224 normal male smoker s were 1.28 +/- 0.82, 1.38 +/- 0.74, and 1.47 +/- 0.62 ng/ml, respectively. There is no significantly statistical difference in the CYFRA 21-1 level a mong the three groups. In conclusion, we suggest that smoking has no effect on the serum levels of CYFRA 21-1.