Embolisation is a way of blocking blood vessels. A doctor injects local anaesthetic around a blood vessel (artery) in the groin or wrist to numb it. They then use x-rays to guide a long plastic tube into the artery, until it reaches the artery that carries blood to the liver. The doctor injects a substance into this artery to block the blood flow. This reduces the supply of oxygen and food to the cancer, which can shrink it or stop it growing.
For primary liver cancer (HCC), embolisation is usually given with chemotherapy. This is called chemoembolisation. You need to be reasonably well to have this treatment. And the part of your liver that is not affected needs to have a good blood supply.
Less commonly, embolisation is given with radiation. This is called radioembolisation or SIRT (selective internal radiation therapy).