CD34 and neoplasm: While the CD34 (endothelial neo-angiogenesis marker) expression increased with tumor progression (PCC +1.8-fold, p= 0.0003; advanced PCC +3.3-fold, p = 0.004), Vegfa was elevated only in advanced PCCs (+2.4-fold, p = 0.0121) and Angpt2 only in early-stage PCCs (+5.2-fold, p = 0.0003).