Fact Sheet: Chemoembolization
A technique called transcatheter chemoembolization is used for some patients with liver cancer or other types of cancer that have spread to the liver. The procedure is a way of delivering cancer treatment directly to a tumor through minimally-invasive means.
Explaining The Procedure
An angiogram, a real-time X-ray that highlights where blood flows, is performed to help the interventional radiologist look in the liver at the tumor without the need for an open incision. The interventional radiologist uses the x-ray images on the TV monitors to insert the catheter (which is like a piece of spaghetti) through a small nick in the skin at the groin and guide it through the artery that feeds the tumor. A combination of chemotherapy drugs and tiny particles, as small as grains of sand, are then injected directly into the tumor. At the end of the procedure, the catheter is removed and pressure is applied to the entry point to prevent bleeding and a band-aid is applied. Patients remain in bed for six to eight hours and leave the hospital within two days.
Chemoembolization can be performed repeatedly on a patient. Typically, patients wait ten to twelve months between treatments. This procedure can also be used in conjunction with other cancer therapies.
Chemoembolization may not be appropriate for patients who have blockages of the veins that supply blood to the liver, cirrhosis of the liver or blockage of the bile ducts.
How Chemoembolization Works
The liver is unique because it has two blood supplies. The portal vein provides 75% of the livers blood supply and the hepatic artery supplies the remaining 25%. Tumors that grow in the liver typically receive their blood supply from the hepatic artery making chemoembolization possible. The drugs can be injected into the artery feeding the tumor while sparing most of the healthy liver tissue that feeds from the portal vein.
The treatment works in three ways to attack the cancer. First, because the chemotherapy is delivered directly to the tumor and doesn't spread throughout the body, stronger doses of cancer-killing drugs can be administered compared to the doses used for standard systemic chemotherapy which is injected through a vein in the arm. Secondly, the tiny particles embolize, or block, the artery and decrease the flow of blood to the tumor causing it to shrink. Finally, by blocking the artery, the particles help contain the chemotherapy keeping it in direct contact of the tumor for a longer period of time—in some cases as long as a month.
This technique also may reduce some of the side effects of standard chemotherapy because the drugs are trapped in the liver instead of circulating throughout the body.
What You Can Expect After Treatment
After the procedure, you will receive prescriptions for oral antibiotics, pain, and nausea. Once home, you may experience fevers for up to a week. For the first two weeks, fatigue and loss of appetite are common. These are all signs of a normal recovery. However, if your fever suddenly becomes higher or your pain changes in intensity or character, contact your physician.
Although a majority of patients can resume their normal activities within a week, most are back to their usual state of health in about one month. Throughout this time it's important to let your physician know how your recovery is progressing.
Eventually, you will get a follow-up CT or MRI scan, as well as blood tests, to determine the size of the treated tumor and how well the chemoembolization worked. CT and MRI scans will continue every three months thereafter to determine how much the tumor ultimately shrunk.
Benefits vs. Risks
- Chemoembolization can stop liver tumors from growing or cause them to shrink in 2/3 of cases treated. This benefit, on average, lasts 10-14 months.
- Chemoembolization can be used in conjunction with other cancer treatments including tumor ablation, radiation and chemotherapy.
- Most patients don't die from the spread of cancer if it is confined to the liver, but rather from liver failure caused by the tumors growth. Chemoembolization can help prevent the growth of a tumor, preserving liver function and a relatively normal quality of life.
- Two randomized controlled trials published in 2002 showed improved survival in patients with hepatoma (primary liver cancer) after chemoembolization compared to supportive care alone.
- Embolus (tiny particles) can lodge in the wrong place and deprive normal tissue of its blood supply.
- Even if antibiotics are given, there is always a risk of infection after embolization.
- There is a risk of an allergic reaction to the dye used in the angiography x-ray.
- There is a risk of kidney damage in patients with diabetes or other pre-existing kidney disease due to the angiography.
- Nausea, hair loss, decreases in white blood cells and platelets, and anemia may occur due to the chemotherapy drug.
- After 1 in 20 procedures, serious complications occur and typically include liver infection or damage to the liver. Liver failure is usually the cause of the 1 in 100 deaths related to this procedure.
Information provided by the Society of Interventional Radiology, www.SIRweb.org © 2005