Liver Cancer: Introduction
What is cancer?
Cancer starts when cells in the body change (mutate) and grow out of control. Your body is made up of tiny building blocks called cells. Normal cells grow when your body needs them and die when your body doesn’t need them any longer.
Cancer is made up of abnormal cells that grow even though your body doesn’t need them. In most cancers, the abnormal cells grow to form a lump or mass called a tumor. If cancer cells are in the body long enough, they can grow into (invade) nearby areas. They can even spread to other parts of the body (metastasize).
What is liver cancer?
Liver cancer is cancer that starts in your liver. It’s also called primary liver cancer. Primary liver cancer is not the same as cancer that started somewhere else in the body and then spread (metastasized) to the liver. Cancer that starts in another organ, such as the colon, breast, or lung, and then spreads to the liver is called secondary liver cancer. Secondary liver cancer is far more common in the U.S. than primary liver cancer. Cancer that has spread to the liver from somewhere else is treated like the original cancer. For instance, lung cancer that has spread to the liver is treated like lung cancer.
Understanding the liver
The liver is a large, pyramid-shaped organ that lies behind your ribs on the right side of your body. It’s under the right lung. It’s divided into right and left lobes.
The liver helps break down and store nutrients. These include sugars, starch, fats, and proteins. It also makes proteins, such as albumin. This helps the body balance fluids. The liver makes clotting factors, which help blood thicken or clot when a person is bleeding. Bile made in the liver is important for digesting food and for other bodily functions.
One of the liver’s most important jobs is to filter out and destroy toxins in the blood. When the liver isn’t working well, chemicals can build up inside the body and cause damage.
What types of cancer start in the liver?
The main types of primary liver cancer include:
Hepatocellular carcinoma. This is the most common liver cancer. About 4 out of every 5 primary liver cancers are this type. It starts in the main liver cells called hepatocytes.
Intrahepatic cholangiocarcinoma. About 10% to 20% of all liver cancers are cholangiocarcinomas. These cancers start in the bile ducts. These are small tubes that carry bile out of the liver and into the gallbladder and intestines during digestion. This type of cancer can also start in the bile ducts outside the liver.
Hepatoblastoma. This is a very rare liver cancer. It’s most often found in young children.
Angiosarcoma. This is another rare form of liver cancer. It starts in blood vessels inside the liver.
Several types of noncancer (benign) tumors can also form in the liver. These include hemangiomas, hepatic adenomas, and focal nodular hyperplasia. These tumors don’t spread to other parts of the body. But they can still cause problems if they grow large enough.
Talk with your healthcare provider
If you have questions about liver cancer, talk with your healthcare provider. Your healthcare provider can help you understand more about this cancer.
Liver Cancer: Risk Factors
What is a risk factor?
A risk factor is anything that may increase your chance of having a disease. Risk factors for a certain type of cancer might include smoking, diet, family history, or many other things. The exact cause of someone’s cancer may not be known. But risk factors can make it more likely for a person to have cancer.
Things you should know about risk factors for cancer:
Risk factors can increase a person’s risk, but they don’t always cause the disease.
Some people with risk factors never get cancer. Other people with cancer have few or no known risk factors.
Some risk factors are very well known. But there’s ongoing research about risk factors for many types of cancer.
Some risk factors, such as family history, may not be in your control. But others may be things you can change. Knowing about risk factors can help you make choices that might lower your risk. For example, if an unhealthy diet is a risk factor, you may choose to eat healthy foods. If excess weight is a risk factor, you may decide to lose weight.
Who is at risk for liver cancer?
Anyone can get liver cancer. But there are some factors that can increase your risk for it. These include:
Chronic viral hepatitis. Worldwide, chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infections are the biggest risk factors for liver cancer. These viruses can cause inflammation that can lead to scarring or cirrhosis.
Alcohol abuse. People who drink a lot of alcohol are at increased risk for cirrhosis. This raises their risk for liver cancer.
Obesity. People who are very overweight are at higher risk for liver cancer.
Cirrhosis. People who have scarring of their liver, whether it’s from hepatitis, alcohol use, or some other cause, have a higher risk for liver cancer.
Diabetes. People with type 2 diabetes have a higher risk for liver cancer. This might be because they tend to be overweight or obese.
Exposure to certain chemicals. Chemicals that have been linked to liver cancer include arsenic in drinking water, vinyl chloride, thorium dioxide (Thorotrast), and anabolic steroids. They also include aflatoxins. Aflatoxins are made by a mold that can grow on stored grains and nuts.
Smoking. People who smoke have a higher risk for liver cancer.
What are your risk factors?
Talk with your healthcare provider about your risk factors for liver cancer. Ask what you can do about them. Some risk factors might not be under your control. But there are some things you can do that might help lower your risk:
Don’t do activities that increase your risk for HBV and HCV infection. Don’t use intravenous drugs, don’t have many sex partners, and don’t handle human blood or fluids without protection. All of these increase your risk of getting these viruses. Also ask your healthcare provider if you should get the hepatitis B vaccine. If you’re at risk for HBV or HCV infection, ask your healthcare provider about getting tested. For people who are infected, medicines can often keep the infections in check or even cure them. This may lower your risk for liver cancer.
Limit the amount of alcohol you drink.
Get to and stay at a healthy weight.
Don’t smoke. If you smoke, get help to quit.
If you have a high risk for liver cancer because of cirrhosis or other reasons, your healthcare provider may test you regularly for liver cancer. Blood tests and ultrasounds can be used to look for early signs of liver cancer. If you think you might be at high risk, talk with your healthcare provider.