[Clinical and prognostic significance of tumor markers cytokeratin 19 fragment, carcinoembryonic antigen, and neuron-specific enolase in lung cancer].

OBJECTIVE: To evaluate the clinical and prognostic significance of the tumor markers cytokeratin 19 fragment, carcinoembryonic antigen and neuron-specific enolase in lung cancer patients. MATERIALS AND METHODS: Serum levels of cytokeratin 19 fragment, carcinoembryonic antigen and neuron-specific enolase were measured using electrochemical luminescence immunoassay in 46 lung cancer patients. Serum levels of cytokeratin 19 fragment, carcinoembryonic antigen, and neuron-specific enolase higher than 3.6 ng/ml, 5.0 ng/ml and 13.0 ng/ml, respectively, were considered as elevated. RESULTS: Cytokeratin 19 fragment, carcinoembryonic antigen, and neuron-specific enolase were elevated in 19.6%, 43.5%, and 63% of patients, respectively. Elevated levels of neuron-specific enolase were detected more frequently in smokers than in ex-smokers (p=0.003). Likewise preoperative levels of carcinoembryonic antigen (p=0.023) and neuron-specific enolase (p=0.007) were statistically higher in smokers than in ex-smokers. A significant correlation was detected between the level of cytokeratin 19 fragments and smoking cumulative exposure (r=0.542, p=0.037). The number of patients with elevated levels of cytokeratin 19 fragment and neuron-specific enolase was higher in more advanced disease than in early lung cancer (p=0.036 and p=0.036, respectively). Preoperative levels of cytokeratin 19 fragment (p=0.017 and p=0.016, respectively) and neuron-specific enolase (p=0.03 and p=0.006, respectively) were significantly associated with more advanced disease and tumor size, as well as tumor histology in non-small cell lung cancer (p=0.03 and p=0.016, respectively). Preoperative levels of cytokeratin 19 fragments were higher in squamous cell carcinoma than in adenocarcinoma (p=0.026). Elevated preoperative serum levels of cytokeratin 19 fragment predict a poor prognosis for lung cancer patients (p=0.007). CONCLUSION: Alteration of serum tumor markers cytokeratin 19 fragment, carcinoembryonic antigen and neuron-specific enolase is associated with particular tumor histology, smoking habit, more advanced disease and poor prognosis.