Liver blood vessel tumour. Magnetic resonance imaging (MRI) scan showing a haemangioma (white, top left) in the liver of a 50 year old man. A haemangioma is an abnormal benign (non-cancerous) growth of blood vessels, also called an arteriovenous malformation. The kidneys are also shown in dark grey, either side of the spinal cord (centre). 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.