Figure 4: Proliferating endothelial cells. A section of a liver metastasis with pushing growth pattern was stained to identify proliferating endothelial cells using Ki67 and CD31. Ki67 was visualised by DAB, and CD31 by Permanent Red. Proliferating endothelial cells (black arrows) and non-proliferative endothelial cell (green arrow). A proliferative cancer cell is indicated with a purple arrow. Bar: 50  𝜇 m.