Abstract:Objective To study the expressions and clinical significance of cytokeratin 19 fragment 21-1(CYFRA21-1) and soluble vascular endothelial growth factor receptor-1 (sVEGFR-1) in pleural effusion of the patients with non-small cell lung cancer (NSCLC). Methods Eighty NSCLC patients with pleural effusion admitted to hospital from January 2017 to January 2018 were selected, in whom the pleural effusion was obtained with aseptic pleural puncture, and the supernatant was separated from venous blood samples.The expression levels of CYFRA21-1 and sVEGFR-1 in pleural effusion and serum were detected respectively by ELISA.Pearson correlation was used to analyze the relationship between CYFRA21-1 and sVEGFR-1. Results In pleural effusion of NSCLC patients, the level of CYFRA21-1 was significantly higher than that in serum of NSCLC patients, and the level of sVEGFR-1 was lower than that in serum of NSCLC patients (P＜0.01).The levels of CYFRA21-1 in pleural effusion of stage Ⅲ-Ⅳ NSCLC, squamous- cell lung carcinoma and dead patients were significantly higher than those in stage Ⅰ-Ⅱ NSCLC, adenocarcinoma and survival patients (all P<0.01).Pearson correlation analysis showed that CYFRA21-1 was negatively correlated with sVEGFR-1(r=-0.390, P<0.01). Conclusion In NSCLC patients, high expression of CYFRA21-1 and low expression of VEGFR-1 in pleural effusion are correlated with pathological stage and tumor type, and there is a negative correlation between CYFRA21-1 and VEGFR-1.