- To investigate levels of tumorigenic and angiogenic markers, including phosphorylated extracellular signal-regulated kinase (p-ERK), vascular endothelial growth factor (VEGF), serum vascular endothelial growth factor receptor-2 (sVEGFR-2), and basic fibroblast growth factor (bFGF), in plasma and tumor tissue samples at baseline and during and after treatment.