The association of lymphatic vessel density and functional configuration with lymph node metastasis in bladder cancer

Objective To determine the intra-and peri-tumoral lymphatic vessel density(LVD) and its correlation with lymph node metastasis in bladder transitional cell carcinoma(BTCC).Methods In 36 samples of BTCC,the lymphatic vessels immunostained with monoclonal antibodies against vascular endothelial growth factor receptor 3(VEGFR-3) and LVD were evaluated in both intra-and peri-tumoral areas.Then the levels of expression of vascular endothelial growth factor C(VEGF-C) by RT-PCR and its correlation with LVD and lymph node metastasis were assessed in 36 samples of BTCC and 8 normal bladder tissues.Results VEGFR-3 was expressed in lymphatic vessel endothelial cytoplasm.As the expression level of VEGF-C became stronger,the intra-and peri-tumoral LVD increased significantly (13.45±2.04 vs(9.38±)1.96;20.25±1.89 vs 14.25±1.44,respectively;P0.05).Meanwhile lymphatic invasion of bladder carcinoma and lymph node metastasis increased significantly(P0.05).Conclusions It is suggested that in BTCC,VEGF-C/VEGFR-3 pathway can contribute to lymphangiogenesis,lymphatic invasion of tumor and lymph node metastasis.Therefore,blocking VEGF-C/VEGFR-3 pathway can inhibit lymphangiogenesis,which will be a new target for treatment of BTCC.