Chemoembolization

Transcatheter chemoembolization is a technique used in the treatment of some patients with primary liver tumors such as hepatocellular carcinoma, or other types of cancer that have spread to the liver, including colorectal, renal cell, and neuroendocrine tumors. The procedure is a way of delivering cancer treatment directly to a tumor through minimally invasive means.

Although the procedure is not a cure for liver cancer, studies have shown that 70 percent or more of patients experience improvement and, depending on the type of cancer, may live longer. Chemoembolization also may relieve pain and other symptoms, make patients more comfortable and improve the quality of their lives. Another advantage is that the procedure may be repeated multiple times.

How Chemoembolization Works

The liver is unique because it has two blood supplies. The portal vein provides 75% of the liver's blood supply and the hepatic artery supplies the remaining 25%. Tumors that grow in the liver typically receive their blood supply predominantly from the hepatic artery. Drugs or embolic material injected into the hepatic artery kill or greatly inhibit the tumor, while sparing most of the healthy liver tissue that is fed via 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, higher local concentrations of chemotherapeutic drugs can be achieved compared to the doses used for standard systemic chemotherapy. 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 with the tumor for a longer period of time.

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.

Benefits:

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.