Evidence of vascular cell proliferation in capillary and pre-capillary vessels in ccRCC. Triple immunofluorescence for endothelial (vWF/blue), mural (SMA/green) and proliferation markers (Ki67/red and red arrows) shows evidence of proliferation of pericytic/smoth muscle A, B, D, and endothelial cells C. Proliferating vascular cells were found throughout ccRCC-associated vascular structures, including capillary A, B, medium-sized D and larger, pre-capillary vessels (C, red dotted line shows the vessel diameter of approximately 100 μm).