Liver cancer begins in the tissues of the liver, an organ that sits in the upper right portion of the abdomen, beneath the diaphragm and above the stomach. The liver has many functions. It helps store nutrients from food, aids with digestion and clears toxins from the body.
Types of liver cancer
Every liver cancer patient is different. The cancer experts at Cancer Treatment Centers of America® (CTCA) have extensive experience in properly staging and diagnosing the disease, and developing a treatment plan that's tailored to your specific type of liver cancer.
There are several types of liver cancer based on the type of cells that becomes cancerous.
Hepatocellular carcinoma (HCC), also called hepatoma, HCC is the most common type of liver cancer accounting for approximately 75 percent of all liver cancers. HCC starts in the main type of liver cells, called hepatocellular cells. Most cases of HCC are the result of infection with hepatitis B or C, or cirrhosis of the liver caused by alcoholism.
Fibrolamellar HCC is a rare type of HCC that is typically more responsive to treatment than other types of liver cancer.
Cholangiocarcinoma (bile duct cancer) occurs in the small, tube-like bile ducts within the liver that carry bile to the gallbladder. Cholangiocarcinomas account for 10-20 percent of all liver cancers. Intrahepatic bile duct cancer begins in ducts within the liver. Extrahepatic bile duct cancer develops in ducts outside of the liver.
Angiosarcoma, also called hemangiocarcinoma, accounts for about 1 percent of all liver cancers. Angiosarcomas begin in the blood vessels of the liver and grow quickly. They are typically diagnosed at an advanced stage. Secondary liver cancer, also known as a liver metastasis, develops when primary cancer from another part of the body spreads to the liver. Most liver metastases originate from colon or colorectal cancer. More than half of people diagnosed with colorectal cancer develop secondary liver cancer.
Most of the information in this section deals with HCC. For more detailed information about cholangiocarcinoma, please see our bile duct cancer center.
Liver cancer symptoms
The symptoms of liver cancer may be different for each person and any one of these symptoms may be caused by other, benign conditions.
When present, common liver cancer symptoms may include:
Weight loss not associated with changes in diet.
Decrease in appetite or a feeling of fullness after a small meal.
Nausea and vomiting not associated with other known conditions.
General weakness and/or fatigue that is persistent, ongoing weakness or fatigue.
Fever that is unrelated to other conditions.
Pain occurring in the upper abdomen on the right side or near the right shoulder blade.
Enlarged liver (hepatomegaly) felt as a mass under the ribs on the right side.
Enlarged spleen felt as a mass under the ribs on the left side.
Abdominal swelling (ascites) or bloating in the abdomen can occur as a mass forms.
Jaundice, which appears as yellowing of the skin and eyes. Jaundice occurs when the liver is not functioning properly.
Understanding liver cancer signs & symptoms
Many of the above mentioned symptoms are similar to other types of benign liver infections or diseases. In the case of liver cancer, the symptoms will continue to evolve and worsen as the disease advances. It is important to see a doctor for an accurate diagnosis if you have any of the above signs of liver cancer.
In rare cases, other disorders may develop as a result of liver cancer, especially in the early stages of the disease. Paraneoplastic syndromes cause symptoms in other parts of the body. Awareness of these symptoms may help with diagnosing liver cancer.
Some paraneoplastic syndromes related to liver cancer include:
Hypercalcemia: High blood calcium levels
Hypoglycemia: Low blood sugar levels
Erythrocytosis: High red blood cell count
Hypercholesterolemia: High cholesterol levels
Gynecomastia: Breast enlargement
Shrinking of testicles in men
Liver cancer risk factors GENERAL
Age: In the United States, the average age at onset of liver cancer is 63 years.
Gender: Men are more likely to develop liver cancer than women, by a ratio of 2 to 1.
Race and ethnicity: In the United States, liver cancer rates are highest in Asian Americans and Pacific Islanders. White Americans have the lowest risk for liver cancer. Chronic infection with Hepatitis B virus (HBV) or Hepatitis C virus (HCV) is the most common liver cancer risk factor. These infections lead to cirrhosis of the liver (see below). Both hepatitis B and C viruses can spread from person to person through sharing of contaminated needles (such as in drug use), unprotected sex, or childbirth. They can also be passed on through blood transfusion; however, this risk has been minimized in the United States since the start of blood testing for these viruses.
Obesity: Being obese can increase the chances of developing liver cancer, probably through development of NASH and eventually, cirrhosis.
Heavy use of alcohol: Alcohol abuse is a common cause of cirrhosis of the liver (see below), which increases a person's liver cancer risks.
Smoking: Tobacco use may increase the risk of developing liver cancer.
Anabolic steroids: Used by athletes to increase strength and muscle mass, the long-term use of anabolic steroids (male hormones) might slightly increase the risk of developing liver cancer. Cortisone-like steroids such as hydrocortisone, dexamethasone, and prednisone do not carry the same risk.
Arsenic: Chronic exposure to naturally occurring arsenic through drinking water (contaminations in some wells) increases the risk of developing some forms of liver cancer.
flatoxins: These are cancer-causing substances made by a fungus that contaminates wheat, corn, soybeans, rice, and some types of nuts. Contamination usually occurs due to storage of the food stuff in a moist, warm environment, more common in warmer and tropical countries. Long-term exposure to aflatoxins is a major liver cancer risk factor, especially in people with HBV or HCV infections. Regular testing by the US-FDA regulates the content of aflatoxins in foods in the United States.
Exposure to certain chemicals: Exposure to vinyl chloride (a chemical used in the making of some plastics) and thorium dioxide (a chemical previously used for x-ray testing) can increase the risk of developing angiosarcoma of the liver. In recent years, strict regulation on exposure to these chemicals has been imposed in the U.S.
Cirrhosis of the liver: Cirrhosis occurs when liver cells become damaged and are replaced by scar tissue. People with cirrhosis have an increased risk of liver cancer. In most cases (up to 90% of the cases in the U.S.), people who develop HCC have underlying cirrhosis. There are several possible causes of cirrhosis. Besides alcohol abuse and chronic HBV or HCV infections, non-alcoholic steatohepatitis (NASH, a fatty liver disease often seen in obese people who consume little or no alcohol), certain types of inherited metabolic diseases (see below), and autoimmune diseases can cause cirrhosis.
Metabolic diseases: Certain types of inherited metabolic diseases can cause cirrhosis and increase the chances of developing liver cancer. Genetic hemochromatosis (an iron-overload disorder that builds up iron stores throughout the body including the liver), tyrosinemia (elevated levels of the amino acid tyrosine), alpha-1-antitrypsin deficiency, porphyria cutanea tarda (deficiency in heme synthesis), glycogen storage disease, and Wilson disease (elevated levels of copper in the liver) are rare diseases that can damage the liver and increase a person's liver cancer risks.
Diabetes: Having diabetes can also increase the risk of developing liver cancer.
Liver cancer stages
TNM system for liver cancer
The American Joint Committee on Cancer (AJCC) TNM system is the most widely accepted method for liver cancer staging. This system bases the staging criteria on the evaluation of three primary factors:
Tumor (T) describes the number and size of the original tumor.
Lymph Node (N) indicates whether the cancer is present in the regional (nearby) lymph nodes.
Metastasis (M) refers to whether cancer has spread to distant parts of the body. (The most common sites of liver cancer spread are the lungs and bones).
A number (0-4) or the letter X is assigned to each factor. A higher number indicates increasing severity. For instance, a T1 score indicates a smaller tumor than a T2 score. The letter X means the information could not be assessed.
Once the T, N, and M scores have been assigned, an overall liver cancer stage is assigned.
Other liver cancer staging systems have been developed that also take into account other factors, such as the function of the liver. However, the staging guidelines described here are based on the current AJCC TNM system.
Other staging systems for lung cancer
Unlike other cancers, liver cancer is complicated by the fact that most patients have liver damage that limits the function of the liver. The liver provides a very important function for the body, aiding in digesting and detoxification. Reduced liver function could result in severe and, even, life-threatening conditions. Reduced liver function may also have implications when choosing treatment options.
Several other liver cancer staging systems have been developed that take into account how the function of the liver may affect the prognosis:
The Barcelona-Clinic Liver Cancer (BCLC) system
The Cancer of the Liver Italian Program (CLIP) system
The Okuda system
The Child-Pugh score is part of the BCLC and CLIP staging systems, and gives the measure of liver function in people with cirrhosis. The system looks at 5 factors including: levels of bilirubin and albumin in the blood, prothrombin time, accumulation of fluid (ascites) in the abdomen, and impact of liver disease on brain function.
Patients with normal liver function are classified as class A, those with mild abnormalities as class B, and those with severe abnormalities as class C. Liver cancer patients with class C cirrhosis are generally not fit to receive treatment.