A blood vessel protruding from the breast can be divided into physiological causes and pathological causes, physiological causes such as thinner subcutaneous tissue, pathological causes such as vena cava obstruction, hemangioma, mastitis and so on. 1. Physiological reasons; may be due to the relatively small amount of subcutaneous fat tissue, skin is more delicate, thin skin, the location of the blood vessels is more superficial and other conditions, so that a blood vessel protrudes from the breast, see more obvious. 2. Pathological causes: such as vena cava obstruction, due to the restriction of venous return, the chest wall veins will be compensatory expansion, resulting in a raised blood vessel on the breast; such as breast hemangioma can be seen around the female breast with earthworm-like blood vessels raised, and hemangioma site has a rounded mass bulge. If mastitis, due to accelerated blood circulation, blood vessels can also appear around the lesion. Therefore, a blood vessel protruding from the breast should be timely medical treatment, clear diagnosis, under the guidance of the doctor to take targeted treatment.