Embolization is a procedure that injects substances to try to block or reduce the blood flow to cancer cells in the liver.
The liver is unusual in that it has 2 blood supplies. Most normal liver cells are fed by branches of the portal vein, whereas cancer cells in the liver are usually fed by branches of the hepatic artery. Blocking the branch of the hepatic artery feeding the tumor helps kill off the cancer cells, but it leaves most of the healthy liver cells unharmed because they get their blood supply from the portal vein.
Embolization is an option for some patients with tumors that cannot be removed by surgery. It can be used for tumors that are too large to be treated with ablation (usually larger than 5 cm across). It can also be used with ablation. Embolization does reduce some of the blood supply to the normal liver tissue, so it may not be a good option for some patients whose liver has been damaged by diseases such as hepatitis or cirrhosis.
People getting this type of treatment typically do not stay in the hospital.
It isn’t yet clear which type of embolization has a better long-term outcome.
Arterial embolization is also known as trans-arterial embolization (or TAE). In this procedure a catheter (a thin, flexible tube) is put into an artery through a small cut in the inner thigh and threaded up into the hepatic artery in the liver. A dye is usually injected into the bloodstream at this time to help the doctor monitor the path of the catheter via angiography, a special type of x-ray. Once the catheter is in place, small particles are injected into the artery to plug it up.
This approach, also known as trans-arterial chemoembolization (or TACE) combines embolization with chemotherapy. Most often, this is done either by using tiny beads that give off a chemotherapy drug for the embolization. TACE can also be done by giving chemotherapy through the catheter directly into the artery, then plugging up the artery.
This technique combines embolization with radiation therapy and is sometimes known as trans-arterial radioembolization.
In the United States, this is done by injecting small beads (called microspheres) that have a radioactive isotope (yttrium-90) stuck to them into the hepatic artery. Brand names for these beads include TheraSphere® and SIR-Spheres®. Once infused, the beads lodge in the blood vessels near the tumor, where they give small amounts of radiation to the tumor site for several days. The radiation travels a very short distance, so its effects are limited mainly to the tumor.
Side effects of embolization
Possible complications after embolization include abdominal pain, fever, nausea, infection in the liver, gallbladder inflammation, and blood clots in the main blood vessels of the liver. Because healthy liver tissue can be affected, there is a risk that liver function will get worse after embolization. This risk is higher if a large branch of the hepatic artery is embolized. Serious complications are not common, but they are possible.
Last Revised: 04/28/2016