The liver is the largest organ inside of the body. It is located on the right side of the abdomen behind the ribs. The liver has many important functions, including:
- Removing harmful substances from the blood.
- Making bile that helps in the digestion of fats from food.
- Storing glycogen (sugar) that the body can use for energy.
When cancer is identified in the liver, it is important to know whether the cancer started in the liver (primary liver cancer) or spread to the liver from another organ such as the colon or lung. The treatment information in this section focuses on primary liver cancer. If your cancer began in another organ, visit the treatment information for that organ. A list of cancer types is available here.
When cells grow abnormally, they can form a mass known as a tumor. Tumors may be benign (not cancer) or malignant (cancer). Benign liver tumors do not spread to other parts of the body, but they may require treatment if they cause symptoms, post a risk of bleeding or rupture, or appear suspicious for cancer.  When treatment is required, benign liver tumors can often be surgically removed. Some of the more common types of benign liver tumors are hemangioma, nodular hyperplasia, and adenoma.
In contrast to benign liver tumors, liver cancer has the capacity to spread to other parts of the body. There are several different types of liver cancer:
- Hepatocellular carcinoma is the most common type of primary liver cancer in adults. It begins in the liver cells known as hepatocytes.
- Cholangiocarcinoma is cancer that develops in the cells that line the bile ducts within the liver.
- Hepatoblastoma is a rare type of liver cancer that develops in children.
- Angiosarcoma and Hemangiosarcoma are rare cancers that start in the blood vessels of the liver.
Each year in the United States, there are more than 21,000 new diagnoses of primary liver cancer and more than 18,000 deaths from the disease. Liver cancer is the fifth leading cause of cancer death among U.S. men, and the ninth leading cause of cancer death among U.S. women. Worldwide, more than 700,000 new cases of liver cancer are diagnosed each year.
Because hepatocellular carcinoma accounts for 80-90% of all primary liver cancers, the liver cancer information that follows focuses on this type of cancer.
Liver cancer often causes no symptoms during its early stages. Symptoms that you may experience as the cancer grows include the following:
- Pain in the upper abdomen on the right side; the pain may extend to the back and shoulder
- Swollen abdomen (bloating)
- Weight loss
- Loss of appetite and feelings of fullness
- Weakness or feeling very tired
- Nausea and vomiting
- Yellow skin and eyes, and dark urine from jaundice
These symptoms can be caused by other conditions and do not necessarily mean that you have cancer, but it’s a good idea to discuss them with your doctor.
When liver cancer is suspected, imaging tests such as ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI) play an important role in confirming the diagnosis. Blood levels of a protein known alpha-fetoprotein (AFP) will also be assessed. Elevated levels of AFP in combination with a liver mass is a common indication of liver cancer. When a liver mass is present but AFP levels are normal, additional imaging procedures may be used to help confirm or exclude the diagnosis of liver cancer.
In contrast to many other types of cancer, biopsy (removal of a sample of tissue) is often not required to diagnosis liver cancer. For most patients (particularly those with cirrhosis), imaging and lab tests provide reliable information about the diagnosis. Furthermore, biopsy of liver cancer carries a small risk of spreading the cancer. Biopsy may be considered, however, in circumstances when there is doubt about the diagnosis.
For additional information, visit
 National Cancer Institute. Adult Primary Liver Cancer Treatment (PDQ®). Available at: http://www.cancer.gov/cancertopics/pdq/treatment/adult-primary-liver/Patient (Accessed December 2, 2008).
 Ibrahim S, Chen CL, Wang SH et al. Liver resection for benign liver tumors: indications and outcome. American Journal of Surgery. 2007;193:5-9.
 American Cancer Society. Global Cancer Facts & Figures 2007. Available at: http://www.cancer.org/docroot/STT/content/STT_1x_Global_Cancer_Facts_and_Figures_2007.asp (Accessed January 8, 2009).
 Lau W-Y, Lai ECH. Hepatocellular carcinoma: current management and recent advances. Hepatobiliary and Pancreatic Diseases International. 2008;7:237-257.
 Silva M, Hegab B, Hyde C, et al. Needle track seeding following biopsy of liver lesions in the diagnosis of hepatocellular cancer: a systematic review and meta-analysis. Gut. 2008;57:1592-1596.