Objective: The aim of this study was to investigate the clinical and prognostic significance of lymphangiogenesis in non-small cell lung carcinoma (NSCLC).
Methods: The expression of lymphatic vessel endothelium markers podoplanin, VEGFR-3 and vascular endothelium marker CD31 was detected in paraffin sections from 68 cases of NSCLC and 8 cases of pulmonary inflammatory myofibroblastic tumor (PIMT) by immunohistochemistry (SP). Microvessel density (MVD) and lymphatic vessel density (LVD) were counted. Specificity of lymphatic vessel endothelium markers was compared between VEGFR-3 and podoplanin. Lymphangiogenesis, quantified by evaluating LVD, was correlated with various clinical pathological parameters and prognostic relevance.
Results: No significant association was found between the number of podoplanin positive vessels and the number of CD31 positive or VEGFR-3 positive vessels (r = -0.171, P = 0.124; r = 0.003, P = 0.979), but the counts of VEGFR-3 positive vessels were associated with CD31 positive vessel counts (r = 0.331, P = 0.002). LVD in PIMT group was significantly lower than that in NSCLC group (P = 0.004). Compared with that without the lymph node metastasis group, LVD in the positive group increased significantly (P = 0.033); LVD in pathological stage III and IV was higher than that in pathological stage I and II (P = 0.001). There was no difference of LVD in different cell differentiation, age and sex groups. The 5-year survival rate for high LVD was significantly lower than that of low LVD. Multivariate analysis showed that LVD was a significant and independent prognostic factor.
Conclusions: Lymphangiogenesis may be a significant prognostic factor for NSCLC.