Liver blood vessel tumour. Coloured magnetic resonance imaging (MRI) scan of an axial (horizontal) section through the abdomen of a 50 year old man showing a tumour (yellow). The front of the body is at top. The tumour is a haemangioma, an abnormal benign (non-cancerous) growth of blood vessels, also called an arteriovenous malformation. It is situated in the liver towards the back of the body on the left hand side. Most haemangioma growths do not produce symptoms, although a few may become painful, or rupture and cause severe bleeding. In these cases surgery would be required.