Liver Cancer

Cancer that begins in the liver is called primary liver cancer, which is relatively uncommon.  However, it is common for cancer to spread to the liver from the colon, lungs, breasts, or other parts of the body.  When this happens, the disease is not liver cancer.  The cancer in the liver is a secondary cancer.  Here we discuss only cancer that begins in the liver itself.

Hepatocellular Carcinoma (HCC), also known as Malignant Hepatoma, is the most common type of liver cancer.

Causes and Development; Contributing Risk Factors

Most primary liver cancers begin in hepatocytes (liver cells).  This type of cancer is called hepatocellular carcinoma or malignant hepatoma.  When liver cancer metastasizes outside the liver, the cancer cells tend to spread to nearby lymph nodes and to the bones and lungs.  When this happens, the new tumor has the same kind of abnormal cells as the primary tumor in the liver.  For example, if liver cancer spreads to the bones, the cancer cells in the bones are actually liver cancer cells.  The disease is metastatic liver cancer, not bone cancer.  It is treated as liver cancer, not bone cancer.  Doctors sometimes call the new tumor "distant" disease.

Similarly, cancer that spreads to the liver from another part of the body is different from primary liver cancer.  The cancer cells in the liver are like the cells in the original tumor.

At the time of writing, no one knows its exact causes.  However, people with certain risk factors have been found to be more likely than others to develop liver cancer.  Studies have shown the following risk factors:

• Chronic liver infection (hepatitis) – Certain viruses can infect the liver, and the infection may be chronic.  The most important risk factor for liver cancer is a chronic infection with the hepatitis B virus or the hepatitis C virus.  These viruses can be passed from person to person through blood or sexual contact.  Liver cancer can develop after many years of infection with the virus.
• Cirrhosis – A disease that develops when liver cells are damaged and replaced with scar tissue.  Cirrhosis may be caused by alcohol abuse, certain drugs and other chemicals, and certain viruses or parasites.  About 5% of people with cirrhosis develop liver cancer.
• Aflatoxin – Liver cancer can be caused by aflatoxin, a harmful substance made by certain types of mold.  Aflatoxin can form on peanuts, corn, and other nuts and grains and is particularly prevalent in Asia and Africa.
• Being male – Men are twice as likely as women to get liver cancer.
• Family history – People who have family members with liver cancer may be more likely to get the disease.
• Age – In the United States, liver cancer occurs more often in people over age 60 than in younger people.

The more risk factors a person has, the greater the chance that liver cancer will develop.  However, many people with known risk factors for liver cancer do not develop the disease.

Signs and Symptoms

Liver cancer is sometimes called a "silent disease" because in an early stage it often does not cause symptoms.  But, as the cancer grows, symptoms may include:

• Pain in the upper abdomen on the right side; the pain may extend to the back and shoulder
• Swollen abdomen (bloating)
• Weight loss
• Loss of appetite and feelings of fullness
• Weakness or feeling very tired
• Nausea and vomiting
• Yellow skin and eyes, and dark urine from jaundice
• Fever

These symptoms are not sure signs of liver cancer.  Other liver diseases and other health problems can also cause these symptoms.

Diagnosis and Tests

If a patient has symptoms that suggest liver cancer, the doctor performs one or more of the following procedures:

• Physical exam – The doctor feels the abdomen to check the liver, spleen, and nearby organs for any lumps or changes in their shape or size.  The doctor also checks for ascites, an abnormal buildup of fluid in the abdomen.  The doctor may examine the skin and eyes for signs of jaundice.
• Blood tests – Many blood tests may be used to check for liver problems.  One blood test detects alpha-fetoprotein (AFP).  High AFP levels could be a sign of liver cancer.  Other blood tests can show how well the liver is working.
• CT scan – An X-ray machine linked to a computer takes a series of detailed pictures of the liver and other organs and blood vessels in the abdomen.  The patient may receive an injection of a special dye so the liver shows up clearly in the pictures.  From the CT scan, the doctor may see tumors in the liver or elsewhere in the abdomen.
• Ultrasound test – The ultrasound device creates a picture (sonogram) of the liver and other organs in the abdomen.  Tumors may produce echoes that are different from the echoes made by healthy tissues.
• MRI
• Angiogram
• Biopsy

If liver cancer is diagnosed, the stage – or extent – of the disease needs to be determined in order to plan the best treatment.  Staging is an attempt to find out the size of the tumor, whether the disease has spread, and if so, to what parts of the body.  Careful staging shows whether the tumor can be removed with surgery.  This is very important because most liver cancers cannot be removed with surgery.

Treatment and Prevention

At this time, liver cancer can be cured only when it is found at an early stage (before it has spread) and only if the patient is healthy enough to have an operation.  However, treatments other than surgery may be able to control the disease and help patients live longer and feel better.  When a cure or control of the disease is not possible, some patients and their doctors choose palliative therapy.  Palliative therapy aims to improve the quality of a person's life by controlling pain and other problems caused by the disease.

People with liver cancer may not feel like eating, especially if they are uncomfortable or tired.  Also, the side-effects of treatment can make eating difficult.  Foods may smell or taste different.  Nevertheless, patients should try to eat enough calories and protein to control weight loss, maintain strength, and promote healing.  Also, eating well often helps people with cancer feel better and have more energy.

Careful planning and checkups are important.  Liver cancer and its treatment may make it hard for patients to digest food and maintain their weight.  The doctor will check the patient for weight loss, weakness, and lack of energy.

Localized resectable liver cancer is cancer that can be removed during surgery.  In these cases, there is no evidence that the cancer has spread to the nearby lymph nodes or to other parts of the body.  Lab tests show that the liver is working well.

Surgery to remove part of the liver is called partial hepatectomy.  The extent of the surgery depends on the size, number, and location of the tumors.  It also depends on how well the liver is working.  The doctor may remove a wedge of tissue that contains the liver tumor, an entire lobe, or an even larger portion of the liver.

In a partial hepatectomy, the surgeon leaves a margin of normal liver tissue.  This remaining healthy tissue takes over the functions of the liver.

For a few patients, liver transplantation may be an option.  For this procedure, the transplant surgeon removes the patient's entire liver (total hepatectomy) and replaces it with a healthy liver from a donor.  A liver transplant is an option only if the disease has not spread outside the liver and only if a suitable donated liver can be found.

Localized unresectable liver cancer cannot be removed by surgery even though it has not spread to the nearby lymph nodes or to distant parts of the body.  In these cases, surgery to remove the tumor is not possible because of cirrhosis (or other conditions that cause poor liver function), the location of the tumor within the liver, or other health problems.

Patients with localized unresectable cancer may receive other treatments to control the disease and extend life:

• Radiofrequency ablation – The doctor uses a special probe to kill the cancer cells with heat.  The probe contains tiny electrodes that destroy the cancer cells.  Sometimes the doctor can insert the probe directly through the skin.  Only local anesthesia is needed.  In other cases, the doctor may insert the probe through a small incision in the abdomen or may make a wider incision to open the abdomen.  These procedures are done in the hospital with general anesthesia.  Other therapies that use heat to destroy liver tumors include laser or microwave therapy.
• Percutaneous ethanol injection – The doctor injects alcohol (ethanol) directly into the liver tumor to kill cancer cells.  The doctor uses ultrasound to guide a small needle.  The procedure may be performed once or twice a week.  Usually local anesthesia is used, but if the patient has many tumors in the liver, general anesthesia may be needed.
• Cryosurgery – The doctor makes an incision into the abdomen and inserts a metal probe to freeze and kill cancer cells.  The doctor may use ultrasound to help guide the probe.
• Hepatic arterial infusion – The doctor inserts a tube (catheter) into the hepatic artery, the major artery that supplies blood to the liver.  The doctor then injects an anticancer drug into the catheter.  The drug flows into the blood vessels that go to the tumor.  Because only a small amount of the drug reaches other parts of the body, the drug mainly affects the cells in the liver.  Hepatic arterial infusion can also be done with a small pump.  The doctor implants the pump into the body during surgery.  The pump continuously sends the drug to the liver.
• Chemoembolization – The doctor inserts a tiny catheter into an artery in the leg.  Using X-rays as a guide, the doctor moves the catheter into the hepatic artery.  The doctor injects an anticancer drug into the artery and then uses tiny particles to block the flow of blood through the artery.  Without blood flow, the drug stays in the liver longer.  Depending on the type of particles used, the blockage may be temporary or permanent.  Although the hepatic artery is blocked, healthy liver tissue continues to receive blood from the hepatic portal vein, which carries blood from the stomach and intestine.  Chemoembolization requires a hospital stay.
• Total hepatectomy with liver transplantation – If localized liver cancer is unresectable because of poor liver function, some patients may be able to have a liver transplant.

Advanced liver cancer is cancer that is found in both lobes of the liver or that has spread to other parts of the body.  Although advanced liver cancer cannot be cured, some patients receive anticancer therapy to try to slow the progress of the disease.  Others discuss the possible benefits and side-effects and decide they do not want to have anticancer therapy.  In either case, patients receive palliative care to reduce their pain and control other symptoms.

Treatment for advanced liver cancer may involve chemotherapy, radiation therapy, or both.

Recurrent cancer means the disease has come back after the initial treatment.  Even when a tumor in the liver seems to have been completely removed or destroyed, the disease sometimes returns because undetected cancer cells remained somewhere in the body after treatment.  Most recurrences occur within the first 2 years of treatment.  The patient may have surgery or a combination of treatments for recurrent liver cancer.