For persons who have liver cancer that cannot be removed by surgery, nonsurgical treatments are used to help relieve symptoms and prolong survival time. A relatively new therapeutic approach, called chemoembolization, is an effective option for some individuals, but not for all. Now, researchers from Spain have identified several characteristics that may help determine ahead of time which patients are not likely to respond to chemoembolization and may therefore require a different form of therapy.
Primary cancer of the liver is characterized by cancer cells that begin to grow in the liver, the largest organ in the human body. These cancer cells can then grow in size and can also spread to the veins or arteries of the liver and/or to other parts of the body (called advanced or metastatic disease). The most common type of primary liver cancer is called hepatocellular carcinoma. Hepatocellular carcinoma often develops in persons whose livers are damaged by other serious conditions, such as hepatitis and/or cirrhosis.
The treatment of hepatocellular carcinoma depends on many factors including the size and stage of the cancer (extent of disease at diagnosis) and the overall health of the patient. When possible, the cancer is completely surgically removed from the liver (called surgical resection), offering a chance for cure. However, when the cancer is too advanced or large to be removed by surgery or the patient is too ill to undergo surgery, effective nonsurgical treatments are needed to control the cancer and prolong survival time. Several options, including a technique called chemoembolization, may be used for this purpose.
One approach to chemoembolization involves injecting 2 types of drugs through a catheter into the main artery that supplies the liver (called the hepatic artery). The 2 types of drugs used are 1) those that cause the hepatic artery to become blocked and 2) chemotherapy drugs (often including cisplatin) that fight the cancer cells. This method of delivery blocks the blood supply to the cancer cells in the liver and still allows the chemotherapy drugs to travel to and attack these cancer cells. This approach is possible because cancer cells in the liver receive much of their blood supply from the hepatic artery, while healthy liver cells also receive blood from what is called the portal vein and can therefore survive blockage of the artery. While chemoembolization can help relieve symptoms and prolong survival in some patients, it does not work for everyone. Recently, Spanish researchers developed a list of selection criteria to help predict which patients would likely and would not likely benefit from chemoembolization.
Researchers evaluated the outcomes and survival times of 143 persons who were treated via chemoembolization for inoperable hepatocellular carcinoma. They discovered that patients who had certain characteristics, or risk factors, were less likely to respond well to chemoembolization. These risk factors included a high serum level of a substance called alfa-fetoprotein, blockage of the portal vein by cancer, the presence of severe cirrhosis, and the presence of cancer in more than 50% of the liver. Using these risk factors, the researchers divided patients into 3 groups based on how many risk factors they had. Two-year survival rates were 60% in those with the fewest risk factors, 30% in those with an intermediate number of risk factors, and 0% in those with the most risk factors. In this last group, less than half the patients survived 1 year.
From these findings, the researchers concluded that chemoembolization appears not to be effective in persons who have a high serum level of alfa-fetoprotein, blockage of the portal vein, the presence of severe cirrhosis, and/or the presence of cancer in more than 50% of the liver. Persons who have inoperable hepatocellular carcinoma with any of these risk factors may wish to talk with their doctor about the risks and benefits of participating in a clinical trial in which other promising new treatment strategies are being studied.
(Cancer, Vol 88, No 12, pp 50-57, 2000)