What is liver cancer?
Liver cancer can be a primary cancer, meaning that the cancer started in the liver, or a secondary cancer, meaning that the cancer started in another part of the body and spread to the liver. The information within this section focuses on primary liver cancer.
Liver cancer begins when cells inside the liver change and grow out of control, forming a mass called a tumour. A tumour can be benign or malignant.
Primary liver cancer
Various types of primary liver cancer can occur in adults, and they are named for the type of cell from which the cancer develops. The main types of liver cancer are hepatocellular carcinoma, cholangiocarcinoma and angiosarcoma:
- Hepatocellular carcinoma (HCC) starts in the hepatocytes, the main type of cell in the liver, and is also known as a ‘hepatoma’. The most common type of primary liver cancer, HCC is often seen in people with liver cirrhosis.
- Cholangiocarcinoma (CCA), also known as bile duct cancer, starts in the bile ducts that connect the liver to the bowel and gall bladder. Types of CCA are classified by the tissue is progresses from: the bile duct cells within the liver (intrahepatic), just outside the liver (hilar) or nearer to the small intestine (distal). Because it may start in cells within the liver, it is sometimes considered a primary liver cancer as well as bile duct cancer.
- Angiosarcoma is a very rare type of liver cancer that starts in the blood vessels.
Secondary cancer in the liver
Most cancers that affect the liver have spread from elsewhere in the body. These are known as secondary cancer of the liver. These secondary cancers are named after the part of the body in which they started. Colon, breast, pancreas, ovarian and lung cancers, as well as melanomas, are all cancers that can spread to the liver.
It is more common for cancer that started in another part of the body to spread to the liver. This is not liver cancer as such, but rather “metastatic cancer” of another organ. These secondary cancers are named after the part of the body in which they started. For instance, pancreatic, colon, stomach, breast, lung, or other cancer that has spread to the liver is still named according to the organ in which it started.
About the liver
The liver is essential for digesting food and removing toxic substances from your body. The liver sits just under your ribs, on the right side of your abdomen, and has two large sections called the right and the left lobes. The gallbladder sits under the liver, along with parts of the pancreas and intestines. These organs work together to digest, absorb and process food. Normally you can’t feel the liver, because it’s protected by the rib cage.
The liver’s main job is to filter the blood coming from the digestive system. The liver also detoxifies chemicals and metabolises drugs. As it does so, the liver secretes bile that ends up back in the intestines (also called the small and large bowel). The liver also makes proteins important for blood clotting and other functions.
Functions of the liver:
- filters blood
- detoxifies the body of harmful chemicals and toxins
- metabolises drugs and alcohol
- makes bile to help dissolve fat, so it can be easily digested
- stores and releases sugars (glucose) as needed
- makes important blood proteins.
Helpful resources:
> Your Guide to Liver Cancer Care (from Cancer Council)
Read more:
> Liver cancer symptoms and risk factors
