Treatment of Liver Cancer
Liver cancer affects nearly 22,000 people in the United States. Until recently, the U. S. Food and Drug Administration (FDA) had not approved any medications specifically for liver cancer. To treat it, doctors mostly had been prescribing chemotherapy intended for other types of cancer. But in late 2007, the drug sorafenib (Nexavar) was approved by the FDA for people with hepatocellular carcinoma—the most common form of liver cancer—when it cannot be treated with surgery. Sorafenib, which was previously approved only for people with kidney cancer, offers renewed hope for people living with this type of liver cancer.
When cancer appears in the liver, it is usually the result of a tumor that has originated in another site, such as the breast. It is less common for liver cancer to be a primary tumor—that is, a tumor that begins in the liver. There are three types of primary liver cancer:
• Hepatocellular carcinoma is the most common type of liver cancer, accounting for about 90 percent of liver cancers. Some hepatocellular carcinomas spread tentacle-like growths throughout the liver. Others start as one tumor that may spread to other parts of the liver. Still others start as small swellings or masses in several parts of the liver.
• Cholangiocarcinoma, also known as bile duct cancer, develops from cells in the bile duct of the liver. The bile duct is a tube that connects the liver to the small intestine. About nine percent of liver cancers are cholangiocarcinomas.
• Angiosarcoma is the rarest form of liver cancer, accounting for only about one percent of liver cancers. Angiosarcoma develops from the blood vessels of the liver.
Close to two thirds of all people with hepatocellular carcinoma have underlying severe liver damage, called cirrhosis. Cirrhosis is most often associated with infection with hepatitis B or C, excessive use of alcohol, and obesity, among other causes.
Cirrhosis can affect many areas of the body. It can block blood flow through the liver, causing swelling of the legs, a buildup of fluid in the abdomen, and, occasionally, bleeding from the upper gastrointestinal tract. In the past, these side effects made treating liver cancer challenging, because the chemotherapy used to treat liver cancer can make them worse.
Risk Factors for Liver Cancer
The following factors can increase a person’s risk of developing liver cancer:
• Viral hepatitis: This virus—most commonly hepatitis B and C—infects the liver. People infected with the hepatitis B or C virus have an increased risk of developing liver cancer.
• Cirrhosis: A condition in which the liver becomes damaged and scar tissue forms. In the United States, excessive use of alcohol is the leading cause of cirrhosis. Other causes include viral hepatitis, obesity, hemochromatosis (a buildup of iron in the liver), and other rare types of liver disease.
• Age: Liver cancer occurs most often in people aged 60 or older. n Gender: Men are more likely to develop liver cancer than women.
• Environmental factors: Exposure to certain chemicals can lead to liver cancer.
Symptoms of Liver Cancer
Many people with liver cancer do not experience any symptoms. Symptoms that may occur include:
• Pain, particularly at the upper right portion of the abdomen or near the right shoulder blade
• Weight loss
• A hard lump under the right ribs
• Weakness or fatigue
Many people with liver cancer also experience symptoms of cirrhosis, including:
• A swollen abdomen
• Confusion
• Bleeding
Liver cancer is usually treated by a team of experts, such as a hepatologist (an expert in the treatment of liver disease), a surgeon (to perform surgical procedures), a medical oncologist (to coordinate all aspects of cancer care), and a radiologist (to locate the tumors in the liver and determine whether they have spread to other organs). Working together, the members of the team set up a treatment plan based on a number of factors, including:
• whether the tumor is in one area of the liver or has spread throughout the liver;
• whether the cancer has spread beyond the liver;
• how much damage the tumor has done to the liver;
• what, if any, underlying liver damage the patient has in addition to the cancer.
Liver cancer can be treated with two types of surgery. The first type is called a hepatectomy—surgical removal of the part of the liver that has been affected by cancer. This procedure can only be performed in people who do not have severe liver damage and whose cancer has not spread widely throughout the liver. The area of the liver not affected by cancer must be functioning well, which can be determined by lab tests. Generally, this type of surgery works best in patients whose tumors are small.
The other surgical option for some people with liver cancer is a liver transplant. Transplants are generally done only in people who have small tumors that cannot be removed completely because of their location or because they have penetrated the major blood vessels in the liver. Liver transplantation also requires that a suitable donor with a healthy liver can be found. It is very important to be examined by a liver cancer expert to determine whether hepatectomy or a liver transplant is an option, as only a small percentage of people with liver cancer are candidates for a surgical procedure.
For liver cancer that cannot be removed surgically, doctors are now using an internal form of radiation called TheraSphere. This treatment consists of tiny radioactive beads inserted into the liver using a catheter—a long, flexible plastic tube. The catheter is placed into a major blood vessel in the leg and moved up through the blood vessel to the hepatic artery, one of two main blood vessels that feeds the liver. Then the TheraSphere beads are infused through the catheter directly into the tumor’s blood supply. Patients remain awake during this procedure, which is usually performed in a hospital’s radiology suite.
Chemotherapy is often used to treat liver cancer. Some patients may be candidates for a procedure called chemoembolization, in which chemotherapy is injected directly into the tumor, and a special material is injected into certain blood vessels to block blood flow to the tumor. (The idea is to kill the tumor in two ways: by delivering a high concentration of chemotherapy directly to the tumor while cutting off the tumor’s blood supply.) However, most patients are given systemic treatments, such as standard chemotherapy (in which one drug or a combination of drugs is given through the bloodstream to the whole body) or one of the newer targeted treatments, described below.
chemoembolization A procedure used to deliver chemotherapy directly to the liver. Chemotherapy is injected directly into the tumor, and a special material is injected into certain blood vessels to block blood flow to the tumor. The idea is to kill the tumor in two ways: by giving a high concentration of chemotherapy directly into the tumor while cutting off the blood supply to the tumor. The procedure generally takes about two hours.
cirrhosis Damage to the liver, resulting in scar tissue. Cirrhosis may be caused by infection with hepatitis B or C, excessive use of alcohol, obesity, or other factors.
epidermal growth factor receptor (EGFR) A protein located on the surface of some cancer cells. When a substance called epidermal growth factor attaches to EGFR, the receptor sends a signal into the cell telling it to divide, promoting the growth of the cancer.
hepatectomy Surgical removal of the part of the liver that has been affected by cancer.
hepatocellular carcinoma The most common type of liver cancer.
liver transplant Partial or complete surgical replacement of a diseased or cancerous liver with a healthy liver from a suitable donor.
targeted treatments Unlike chemotherapy, targeted treatments attack specific molecules and cell mechanisms thought to be important for cancer cell survival and growth. This specific targeting helps to spare healthy tissues and causes less severe side effects.
vascular endothelial growth factor (VEGF) A substance that stimulates the growth of new blood vessels that feed tumors.
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