Overview

Function of the liver

The liver is the largest internal organ in the body, and its functions are vital to the digestion of food. No one can survive without a liver. Functions of the liver include:

• Collecting and filtering blood from the intestines
• Processing and storing needed nutrients absorbed from the intestines
• Chemically metabolizing (changing) some nutrients into energy or to repair and build tissue
• Producing some of the body’s blood clotting factors
• Removing toxic wastes from the body
• Helping maintain the proper sugar level in the body

Risk Factors and Prevention

A risk factor is anything that increases a person’s chance of developing cancer. Some risk factors can be controlled, such as smoking, and some cannot be controlled, such as age and family history. Although risk factors can influence the development of cancer, most do not directly cause cancer. Some people with several risk factors never develop cancer, while others with no known risk factors do. However, knowing your risk factors and communicating them to your doctor may help you make more informed lifestyle and health-care choices.

The following factors can raise a person’s risk of developing HCC. The main risks in the United States are chronic liver infection with the hepatitis B or hepatitis C virus or cirrhosis of the liver. HCC usually develops several decades after such an infection starts.

Viral hepatitis. Viral hepatitis is the largest risk factor for this type of cancer. Hepatitis viruses are viruses that infect the liver. Two common types are hepatitis B and hepatitis C. People who are carriers of the hepatitis B virus face up to a 100-fold increased risk of developing adult primary liver cancer.

Viral hepatitis can be transmitted through exposure to another person's blood or bodily fluids through injury, by sharing needles during drug use, or by sexual contact. In the case of hepatitis B, an unborn baby or infant can become infected from an infected mother, although this can be avoided by vaccinating the baby. If you develop acute hepatitis B or C and then “clear the virus,” you have no increased risk of liver cancer. Only people who don’t clear the virus (those who become “carriers”) are at an increased risk. Your doctor will be able to perform blood tests that tell if you have cleared the virus.

Cirrhosis. Cirrhosis develops when liver cells are damaged and are replaced by scar tissue. Most cirrhosis in the United States is caused by alcohol abuse. Other causes are viral hepatitis (types B and C, as mentioned above), too much iron in the liver from a disease called hemochromatosis, and some other rare types of chronic liver disease.

Age. In the United States, adult primary liver cancer occurs most often in people over age 60.

Gender. Men are more likely than women to develop this type of cancer.

Symptoms

People with HCC may experience no symptoms, particularly when the tumor is detected early as part of a screening program. When symptoms do occur, they include:

• Pain, especially at the top right of the abdominal area or near the right shoulder blade, or in the back
• Unexplained weight loss
• A hard lump under the ribs on the right side of the body, indicating either the tumor itself or that the liver has increased in size
• Weakness or fatigue

Diagnosis

Physical examination. If a person has symptoms of HCC, the doctor will feel the abdomen to check the liver, spleen, and other nearby organs for lumps, swelling, or other changes. The doctor will also look for an abnormal buildup of fluid in the abdomen and for signs of jaundice (yellowing of the skin and whites of the eyes).
Blood tests. At the same time as the physical examination, the doctor will most likely do a blood test to look for a substance called alpha-fetoprotein (AFP). In the United States, AFP is found in elevated levels in the blood of about 50% to 70% of people who have adult primary liver cancer. The doctor will also test the patient’s blood to see if he or she has hepatitis B or C. Other blood tests can show how well the liver is working.
In addition, other tests are commonly needed to diagnose HCC and to determine the location of the tumor in the liver and if it has spread to other parts of the body. After the physical examination and blood tests, the doctor may recommend one or more of the following tests:
Ultrasound. An ultrasound uses sound waves to create a picture of the internal organs. The sound waves bounce off the liver, other organs, and tumors. Each creates a different appearance on a computer monitor.
Computed tomography (CT or CAT) scan. A CT scan creates a three-dimensional picture of the inside of the body with an x-ray machine. A computer then combines these images into a detailed, cross-sectional view that shows any abnormalities or tumors. Sometimes, a contrast medium (special dye) is injected into a patient’s vein to provide better detail.
Magnetic resonance imaging (MRI). An MRI uses magnetic fields, not x-rays, to produce detailed images of the body. A contrast medium may be injected into a patient’s vein to create a clearer picture.
Angiogram. An angiogram is an x-ray picture of the blood vessels. A dye is injected into the bloodstream, so the blood vessels of the liver show up on an x-ray.
Laparoscopy. A laparoscopy uses a thin, lighted tube to look at the liver and other internal organs. The tube is inserted through a small incision in the abdomen. The procedure is usually done under sedation and local anesthetic to numb the area; it doesn’t usually require a general anesthetic.