Chronological change of serum carcinoembryonic antigen (CEA) concentrations and pulmonary function data after cessation of smoking in subjects with smoking-associated CEA abnormality.

We evaluated changes in serum carcinoembryonic antigen (CEA), peripheral neutrophil concentrations, and ratio of the forced expiratory volume in 1 s to the forced vital capacity (FEV1%) values after cessation of smoking in subjects with smoking-associated CEA abnormality (>5.0 ng/ml) (n=119). In all 25 subjects who gave up smoking (ex-smokers), CEA concentrations 1 year after the cessation decreased within the reference range and neutrophil concentrations were lower than those while smoking. However, both concentrations after 3 years were still higher than those who have never smoked (non-smokers) (n=86). Average CEA and neutrophil concentrations in 94 subjects who continued to smoke (smokers) were stable. There was no difference between chronological changes of FEV1% over 3 years in ex-smokers and in smokers. However, FEV1% values for 3 years in ex-smokers were lower than those in non-smokers. These findings suggest that the ex-smokers who gave up smoking 3 years ago are still affected by past smoking.