What is Chemoembolization?
Chemoembolization is a palliative treatment for tumors found in the liver. This can be a tumor that started in the liver (primary liver cancer or hepatoma) or a liver tumor that has metastasized (spread) from another area of the body. Chemoembolization can be used alone or in addition to chemotherapy, radiation therapy or radiofrequency ablation.
Chemoembolization delivers chemotherapy directly to the liver tumor through the artery that supplies blood to the tumor. The artery is then blocked ("embolized") to cut of blood flow to the tumor. This procedure accomplishes a few things:
- Deprives the tumor of oxygen and nutrients once the blood supply is blocked.
- Because the chemotherapy is injected directly at the tumor, the dose is higher than what can be given safely through a vein (IV).
- Because the artery is blocked, no blood washes through the tumor. As a result, the chemotherapy stays in the tumor for a much longer time – as long as a month.
- There are fewer or milder side effects compared with chemotherapy given in a vein because the medications are trapped in the liver and not circulating through out the body.
How does chemoembolization work?
The liver is unique in having two blood supplies – an artery (hepatic artery) and a large vein (the portal vein). The normal liver gets about 75% of its blood from the portal vein. When a tumor grows in the liver, it receives almost all of its blood supply from the hepatic artery. Therefore, chemotherapy drugs injected into the hepatic artery at the liver reach the tumor very directly, sparing most of the healthy liver tissue. Then, when the artery is blocked with embolization, nearly all of the blood supply is taken away from the tumor, while the liver continues to be supplied by blood from the portal vein.
Is chemoembolization an appropriate treatment for me?
Chemoembolization only treats tumors in the liver and will have no effect on other cancer in your body. For this reason, chemoembolization may be used in conjunction with other treatments that can reach cancer cells in other areas of the body. Tumors that may be treated by chemoembolization include:
- Hepatoma (primary liver cancer).
- Metastasis (spread) to the liver from solid tumors (i.e. lung, breast, colon cancers, sarcoma, melanoma).
You may need to have liver function tests and a CT scan or MRI to determine if your tumor is a candidate for this procedure. In some cases, there may be blockage of the portal vein or bile ducts or cirrhosis of the liver, which may prevent the use of chemoembolization.
How is the procedure done?
Chemoembolization is done in the interventional radiology department by an interventional radiologist. An interventional radiologist is a physician with advanced training in minimally invasive treatments that use radiology imaging to guide them. You may also encounter nurses, radiology technicians and nurse practitioners in this department.
You will be told to not eat or drink after midnight the night before the procedure. Patients typically stay in the hospital anywhere from 1-4 nights after the procedure. When you arrive in the interventional radiology (IR) department, you will have an IV placed and will be given medications, including IV fluids, antibiotics and sedative medication.
Once in the procedure room, the doctors will place a small catheter (IV) into an artery (femoral artery) in your groin and perform an arteriogram, which is done by infusing dye through the catheter, into the hepatic artery and then taking x-rays to map the arteries feeding blood to your liver. The dye can make you feel flushed or warm, but the feeling will pass in a few minutes. Once the arteries are identified, the catheter is directed into the branch of the artery that supplies blood to the tumor, and the chemoembolization mixture is injected. Further x-rays may be done to confirm that the tumor has been treated. The catheter is then removed, pressure is applied to the site and a gauze dressing put over the site where the catheter went in. The entire procedure takes 1½-2 hours.
Once the procedure is complete, you will be taken to a hospital room where you will be monitored closely. You will need to lie flat in bed for 6-8 hours. You will be given IV fluids and anti-nausea or pain medications if needed. Most patients are discharged from the hospital the next day and are able to resume normal activities within a week.
What are the side effects of chemoembolization?
Following the procedure, you may experience fever, pain and/or nausea. These symptoms may last a few hours to up to a week, and are easily treated by medications. You may experience fatigue (feeling tired) or loss of appetite for 2 weeks or more. You may also notice slight hair loss. More serious complications occur in less than 3% of chemoembolization procedures. These can include infection, development of an abscess in the liver and bleeding.
How will chemoembolization help me?
Chemoembolization is a treatment, but not a cure. About 70% of patients will have their liver tumors stop growing and/or shrink, which may improve quality of life and survival.
Resources and further reading
RadiologyInfo.org. Chemoembolization. April 2016. Found at: http://www.radiologyinfo.org/en/info.cfm?pg=chemoembol#overview
Society of Interventional Radiology. Minimally Invasive Treatments Help Cancer Patients Extend Life and Improve Quality. 2016. Found at: http://www.sirweb.org/patients/liver-cancer/