Endothelial Microparticles and Vascular Endothelial Growth Factor in Patients With Head and Neck Cancer Undergoing Radiotherapy or Radiochemotherapy.

BACKGROUND: Endothelial microparticles (EMPs) released from activated or apoptotic endothelial cells may play a role in coagulation and thrombus formation. However, there is insufficient evidence regarding the impact of EMPs on angiogenesis in patients with cancer. MATERIALS AND METHODS: Sixteen patients with head and neck cancer (HNC) undergoing radiotherapy/radiochemotherapy (RT/RCT) and 10 healthy controls were studied. Serum EMPs were counted by flow cytometry, and vascular endothelial growth factor (VEGF) was measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: The mean EMP level was significantly higher in patients with HNC before RT/RCT (1,601±1,479 EMP/µl) compared to the control group (782±698 EMP/µl). The number of EMPs was not notably increased after RT/RCT (1,629±769 EMP/µl). There was no significant correlation between the plasma EMP number and concentration of VEGF before (r=0.131; p=0.625), 1 day after (r=-0.042, p=0.874), nor 3 months after RT/RCT (r=0.454, p=0.076). CONCLUSION: Released EMPs may not influence promotion of neovascularization in patients with HNC.