Abstract: Objective:To investigate the relationship of nm23and VEGF expression with hilar lymph node micrometastasis and the prognosis of stage Ⅰnon-small cell lung cancer (NSCLC). Methods:Immunohisto -chemistry was used to detect nm 23and VEGF protein expression in primary cancer tissue and cytokeratins in
86hilar lymph nodes from 40patients with stage ⅠNSCLC. Kaplan-meier method and Log rank test were used to analyze the 5-year survival. Results: The rate of positive hilar lymph node micrometastasis was 12.5% or stage ⅠNSCLC. Lymph node micrometastasis was not statistically correlated with gender, age, histologic type, differentiation, primary tumor size or VEGF protein expression ( P>0.05). But it was reversely associated with nm23protein expression in primary cancer tissue of NSCLC ( P<0.05). The 5-year overall survival of pa -tients with well-differentiated NSCLC, positive nm 23 expression and negative lymph node micrometastasis was better than those with moderately and poorly differentiated NSCLC, negative nm23expression and posi-tive lymph node micrometastasis ( P<0.05). Lymph node micrometastasis and nm 23protein expression were identified as two independent prognostic factors for stage ⅠNSCLC by univariate Cox regression analysis. Conclusion:nm23protein expression in primary cancer tissue of stage ⅠNSCLC is closely associated with hilar lymph node micrometastasis. nm 23protein and hilar lymph node micrometastasis are two independent prognostic factors for stageⅠNSCLC. Patients with nm23protein deletion and positive lymph node microme-tastasis have a poor prognosis.