Most cancers in the liver started somewhere else, like the colon, and then spread to the liver. But cancer can also start in the liver itself.
- What is liver cancer?
- What your liver does
- Types of primary liver cancer
- Other related conditions
- Risk factors
- How common is liver cancer?
- Next steps
What is liver cancer?
Primary liver cancer occurs when cells in the liver begin to grow abnormally.
Cancer cells do not respond to regular cell growth, division and death signals like healthy cells do. They also don’t organize normally. Instead they grow into a tumor, which may invade surrounding layers of tissue and possibly spread to other organs.
Cancer that starts in another part of the body, such as the colon or breast, can spread (metastasize) through the bloodstream to the liver. This is called secondary liver cancer.
- Secondary cancers are also named based on the place where they started. For instance, colon cancer that spreads to the liver (or another organ) is metastatic colon cancer.
- The areas of cancer that develop in the liver are called liver metastases.
What your liver does
Your liver is a vital organ with many important functions.
- It makes bile that helps digest your food.
- It processes and stores many of the nutrients absorbed from your intestine.
- It produces some of the clotting factors that keep you from bleeding too much when you get injured.
- It detoxifies harmful substances in your blood so they can be excreted in stool and urine.
Your liver gets its blood supply from two sources.
- Your portal vein carries nutrient-rich blood to your liver from your intestines.
- Your hepatic artery carries oxygen-rich blood to your liver from your lungs.
Small tubes, or ducts, inside your liver collect bile.
- The small ducts carry bile into two larger ducts (right and left hepatic ducts), which lead outside your liver.
- The two larger ducts join to form your common hepatic duct.
Your gallbladder stores bile.
- When you eat, bile flows from your gallbladder through your cystic duct.
- Then it flows into your common bile duct (where the cystic duct joins the common hepatic duct) and into the first part of your small intestine (duodenum).
Types of primary liver cancer
The liver is made up of several types of cells, so several types of tumors can form there. Some are malignant (cancerous), and some are benign (noncancerous).
Most primary liver cancers are hepatocellular carcinoma or intrahepatic cholangiocarcinoma.
Hepatocellular carcinoma (HCC)
- Roughly 80 percent of primary liver cancers are HCCs, which begin in liver cells called hepatocytes.
- HCCs occur most often in people whose livers have been damaged, such as by chronic infection with the hepatitis B or C virus or by alcohol abuse.
- People with diabetes, hyperlipidemia and obesity (metabolic syndrome) are also at increased risk, probably because they develop fatty liver disease.
- A small proportion of HCCs may arise from benign tumors called hepatic adenomas.
- Hepatocellular carcinoma is also called hepatocellular cancer or hepatoma.
Intrahepatic cholangiocarcinoma (ICC)
- Most other primary liver cancers are ICCs, which resemble cells that line the bile ducts inside the liver.
- People with chronic inflammation and damage to their liver (such as those with cirrhosis, sclerosing cholangitis, pyogenic cholangiohepatitis or choledochal cysts) are at higher risk for ICC.
- Treatment for ICC is often similar to treatment for hepatocellular carcinoma.
Other primary liver cancers
These are other rare forms of primary liver cancer, including:
- Angiosarcoma, hemangiosarcoma, hemangiopericytoma and hepatic epithelioid hemangioendothelioma — which start in the blood vessels of the liver
- Hepatoblastoma — which affects children
- Biliary cystadenocarcinoma — which occurs mainly in women
- Fibrolamellar hepatocellular carcinoma — which usually affects people younger than 40
Other conditions related to the liver
The Liver Tumor Clinic treats other conditions, too, including cancer in structures whose function is closely related to the liver, benign liver tumors and liver cysts.
Cancers of related structures
Cancers in structures related to the liver include:
- Extrahepatic cholangiocarcinoma — begins in the bile duct outside the liver that drains into the intestine
- Hilar cholangiocarcinoma — begins in the bile ducts in the area where the right and left hepatic ducts meet to form the common hepatic duct
- Gallbladder carcinoma — uncommon cancer, often associated with gallstones, that begins in the lining of the gallbladder
Benign liver tumors
Many liver tumors are benign, meaning they cannot invade nearby tissue or spread to other organs. Even so, sometimes they need treatment because they cause symptoms or can transform into cancers. They include:
- Hemangioma — the most common liver tumor. These tumors are made up of a tangle of blood vessels. They rarely cause symptoms or require treatment. There is no evidence that they develop into cancer.
- Focal nodular hyperplasia — tumor-like masses usually discovered incidentally (when a doctor is diagnosing, monitoring or treating some other condition). With few exceptions, they do not cause symptoms or require treatment.
- Liver adenoma — often associated with prolonged use of hormonal contraception with high estrogen content or with other forms of hormonal imbalance, as in polycystic ovarian syndrome. Most cause no symptoms, but they may bleed, and rarely they transform into hepatocellular carcinoma.
Cysts are benign encapsulated structures that contain fluid. Liver cysts are common, but they rarely cause symptoms and, therefore, are usually not detected. There are various types, including:
- Simple cysts — the most common and the least likely to cause symptoms.
- Complex cysts — cysts with features that may be signs of an underlying disease process and may require treatment.
- Polycystic liver disease — a rare, usually hereditary, condition in which many cysts grow throughout the liver. If there are too many or they grow too large, they may cause symptoms and require treatment.
- Echinococcal cysts — cyst that form due to a parasitic disease caused by the tapeworm of genus Echinococcus.
- Choledochal cysts — part of a congenital condition that blocks the flow of bile from the liver to the gallbladder and intestine, usually treated in childhood. People with choledochal cysts are at increased risk of developing cholangiocarcinoma.
- Biliary cystadenomas — a rare form of benign fluid-filled tumors associated with the bile ducts that occur mainly in women. They carry a risk of becoming cancer and often require surgery.
Symptoms of liver cancer
Liver cancer typically doesn’t cause symptoms until the disease is advanced. The following symptoms could occur:
- Lump in your right side near the bottom of your ribcage
- Pain in the upper right side of your abdomen, right shoulder or back
- Nausea or vomiting
- Unexplained weight loss
- Lack of appetite
- Feeling unusually full after only a small meal
- Yellow-green color of your skin and whites of your eyes (jaundice)
- Dark urine
- Fever without infection
- Worsening of chronic hepatitis or cirrhosis
- Enlargement of your liver (upper right abdomen) or spleen (upper left abdomen)
- Swelling or fluid build-up in your abdomen (ascites)
- Itching (pruritis)
Some symptoms of liver cancer are the same as symptoms of other problems, and they do not necessarily mean you have cancer. Talk to your doctor if you have any symptoms that concern you.
Diagnosing liver cancer
Liver cancer is usually diagnosed through:
- Blood tests — such as to measure the level of a liver protein (alpha-fetoprotein, or AFP); to check your liver function (such as bilirubin or albumin levels), kidney function, blood clotting and blood cell levels; to test your immune system’s response to certain viruses (viral serology); and to test for substances that may be found if you have cancer (tumor markers, such as CA19-9 or CEA)
- Imaging studies — such as ultrasound to screen for liver cancer and guide biopsies; computed tomography (CT) or magnetic resonance imaging (MRI) scan to provide detailed images of the inside of your body; angiography to examine your blood vessels; cholangiography to examine your bile ducts; or positron-emission tomography (PET) scan with CT to examine the metabolism of tumors throughout your body
- Liver biopsy — removing a sample of the tumor with a hollow needle pushed through your skin into your liver (fine-needle aspiration or core needle biopsy) or during surgery (usually laparoscopically, through small incisions in your abdomen) and examining the cells under a microscope
Liver cancer stages
Your team will recommend treatment based on the stage of your cancer, the health and function of your liver and your overall health.
The stage depends on the following:
- How many tumors you have
- How large your tumors are
- Whether the cancer has grown into blood vessels
- Whether the cancer has spread to lymph nodes or distant parts of your body
There are multiple systems for staging liver cancers, including Roman numeral staging. In this system, liver cancers are grouped into stages I through IV, with stage I being the least advanced and stage IV being the most advanced.
Along with staging your cancer, your doctor will check the following aspects of your liver function to come up with a score (Child-Pugh score or MELD score):
- Levels of bilirubin (a yellow pigment made in the liver), albumin (a protein made in the liver) and creatinine (a measure of kidney function)
- How well your liver is making the substances that help your blood to clot (prothrombin time)
- Severity of fluid build-up in your abdomen (ascites)
- Severity of hepatic encephalopathy (which occurs when liver problems affect your mental function)
Risk factors for liver cancer
Men are nearly three times as likely as women to get liver cancer, and people who have family members with liver cancer may be more likely to get the disease. In the United States, most people with liver cancer are diagnosed in their early 60s.
These factors may also increase your risk:
- Chronic infection with hepatitis B or C virus
- Cirrhosis (scarring) of the liver, such as from heavy alcohol use
- Metabolic syndrome (obesity, diabetes, high blood pressure and hyperlipidemia)
- Long-term exposure to aflatoxin (produced in tropical and subtropical regions by a fungus that may contaminate rice, peanuts, wheat and soybeans), anabolic steroids or arsenic
If you have chronic liver disease (cirrhosis), talk with your doctor about having liver cancer screenings. Generally, doctors recommend screening with ultrasound every six months.
How common is liver cancer?
Each year about 42,000 men and women in the United States are diagnosed with cancer of the liver or the bile ducts inside the liver.