Abstract: Abstract Objective： To investigate the union expression of CEA、NSE and CYFRA21-1 in non-small cell lung cancer and to explore the relationship between the tumor markers and pathological staging of non-small cell lung cancer. Methods: 143 patients in non-small cell lung cancer with their postoperative pathological dates were collected .The expression results of CEA、NSE and CYFRA21-1 were measured before operation in all patients and then were used to study the correlation between them and postoperative pathological staging . Results: The levels of serum CEA and CYFRA21-1 in patients are different when T、N stages and group numbers of metastasis lymphnodes are not same (P＜0.05orP＜0.01).Levels in patients of N2 with multi- metastasis groups lymphnodes were significantly higher than those in patients of N1 and N2 with single-metastasis group lymphnode . The levels of serum NSE in patients of different T stages(T1 and T3) was significantly different (P＜0.05),but there 's same level in patients with the different pathological N stages(P＞0.05). Conclusion: Preoperative detection of the serum concentration of CEA and CYFRA21-1 has important clinical significance on the accurate judgment of tumor staging in patients with non-small cell lung cancer.

Key words: non-small lung cancer, pathological staging, carcinoembryonie antigen, cytokeratin 19 fragements, neu-ron-specific enolase