Cancer Institute A national cancer institute
designated cancer center

What is Liver Cancer


Liver cancer is cancer that starts in the cells of the liver. Cancer that begins in the liver is called primary liver cancer. This cancer is uncommon in the United States. It is the most common cancer in some African and East Asian countries, though.

Liver cancer tends to develop in several parts of the liver at the same time. When the cancer does spread outside of the liver, it may move to the tissues close to the liver and to the diaphragm, the muscle that separates the lungs from the abdomen. It is uncommon for liver cancer to spread to lymph nodes.

Diagram of the liver
Diagram of the liver (click to enlarge)

Primary liver cancer is not the same as cancers that have started somewhere else in the body and have then spread to the liver. These are called liver metastases. Cancer that starts in other places, such as the colon, breast, or lung, and then spreads to the liver is called secondary liver cancer. Almost all other cancers, if they spread, can spread to the liver. Secondary liver cancer is more common in the United States than primary liver cancer. Cancer that has spread to the liver is treated like the original cancer. For instance, lung cancer that has metastasized to the liver is treated like lung cancer.

What Are Tumors?

Tumors are abnormal masses of tissue that form when cells begin to reproduce at an increased rate. Both non-cancerous (benign) and cancerous (malignant) tumors can develop in the liver.

Cancerous Liver Tumors

Cancerous (malignant) tumors in the liver have either originated in the liver (primary liver cancer) or spread from cancer sites elsewhere in the body (metastatic liver cancer). Most cancerous tumors in the liver are metastatic.

Hepatoma (primary liver cancer)

Also called hepatocellular carcinoma, this is the most common form of primary liver cancer. Chronic infection with hepatitis B and C increases the risk of developing this type of cancer. Other causes include certain chemicals, alcoholism, and chronic liver cirrhosis.

Other Types of Primary Liver Cancer

Other, less common primary liver cancers include the following:

Metastatic Liver Cancer

Cancer that starts in another part of the body and spreads to the liver is called metastatic liver cancer. Cancer that has spread from other areas in the body to the liver usually originated in the lung, breast, colon, pancreas, and stomach. Leukemia and other blood cancers sometimes also spread to the liver.

Noncancerous Liver Tumors

Noncancerous (benign) tumors are quite common and usually do not produce symptoms. Often, they are not diagnosed until an ultrasound, computed tomography scan, or magnetic resonance imaging scan is performed. There are several types of benign liver tumors, including hepatocellular adenoma and hemangioma.

Hepatocellular Adenoma

This benign tumor is linked to the use of certain drugs. Most of these tumors remain undetected. Sometimes, an adenoma will rupture and bleed into the abdominal cavity, requiring surgery. Adenomas rarely become cancer.


This type of benign tumor is a mass of abnormal blood vessels. Treatment is usually not required. Sometimes, infants with large liver hemangiomas require surgery to prevent clotting and heart failure.

Stanford Medicine Resources:

Footer Links: