Hepatoblastoma and other childhood liver cancers

Overview

Although liver cancer (also called hepatoma) is rare in children, there are several types that can affect them. The most common is hepatoblastoma. But even that is very rare: Each year, only 100 to 125 new cases of hepatoblastoma are diagnosed in North America. These cases are usually in children under the age of 3.

One of the body's largest organs, the liver has many functions. These include filtering harmful substances from the blood; producing bile, which helps digest fats from food; and storing glycogen (a form of sugar), which the body uses for energy.

Cancers arise when cells begin growing uncontrollably and become abnormal. A primary liver cancer is one that starts in the liver, even if it later spreads to other parts of the body. A cancer that began elsewhere and later spreads to the liver is called secondary liver cancer. Hepatoblastoma is a primary liver cancer.

What is hepatoblastoma?

Hepatoblastoma is a tumor that develops when genetic changes in liver cells cause them to grow and divide abnormally. Researchers aren't sure what causes the genes to change, but children born with certain genetic conditions have an increased risk of developing the disease. The conditions include:

• Aicardi syndrome
• Beckwith-Wiedemann syndrome
• Familial adenomatous polyposis
• Glycogen storage disease
• Hemihypertrophy (when overproduction of bone or soft tissue in one side or part of the body causes it to grow larger than the other)
• Simpson-Golabi-Behmel syndrome
• Trisomy 18

Other risk factors for hepatoblastoma include:

• Premature birth
• Low birth weight
• Family history of familial adenomatous polypopsis

While any cancer diagnosis is scary, you may feel somewhat reassured to know that hepatoblastoma treatment is typically effective. When detected and treated before it spreads, the condition has a survival rate that can reach 90%.

What other liver cancers can occur in childhood?

Less commonly, children develop other types of liver cancer, such as:

• Hepatocellular carcinoma. The second most common childhood liver cancer, hepatocellular carcinoma usually occurs in children over 5. Several conditions increase children's risk for the disease, including:
  • Hepatitis B infection passed from mother to infant at birth
  • Alagille syndrome
  • Glycogen storage disease
  • Progressive familial intrahepatic cholestasis
  • Tyrosinemia
• Childhood undifferentiated embryonal sarcoma of the liver. This very rare tumor usually develops in the liver's right lobe and often spreads to the rest of the liver and the lungs. It usually affects children between 5 and 10 but can also occur during adolescence.
• Infantile choriocarcinoma of the liver. This very rare cancer starts in the placenta during a pregnancy and spreads to the fetus. The tumor, which can be treated, is usually found in the first few months after the baby is born.

Symptoms of liver cancer

In early stages, liver cancer may not cause symptoms. Some signs that may develop are similar to those of other conditions, so it's important to have your child checked by a doctor if they experience any of the following:

• A painless lump in the abdomen
• Loss of appetite
• Abdominal swelling
• Persistent pain in the abdomen
• Persistent nausea or vomiting
• Weight loss for an unknown reason

Diagnosis of liver cancer

A series of tests and procedures are used to diagnose childhood liver cancers, including hepatoblastoma. Initially, your child's doctor will perform a thorough physical exam. If this raises concern about a tumor in the liver, the doctor may want to run certain diagnostic tests, such as:

• Serum tumor marker test. This blood test measures two substances released by tumor cells or other cells in response to tumors: a protein called alpha-fetoprotein (AFP) and a hormone called beta-human chorionic gonadotropin (beta-hCG). High levels can indicate liver cancer, as well as other types of cancer and noncancerous liver tumors.
• Complete blood count (CBC). This blood test measures the numbers of different blood components, including red and white blood cells. Abnormal counts can be a sign of disease.
• Liver function tests. These blood tests measures certain substances that the liver releases into the blood. Higher-than-normal levels can indicate liver cancer.
• Abdominal ultrasound. This test uses high-frequency sound waves to create pictures of internal organs and blood vessels – images that allow doctors to see whether a tumor is present.
• Abdominal computed tomography (CT) scan. Computer programs process X-rays taken from various angles to produce detailed cross-sectional images of organs and blood vessels, which may reveal the presence of a tumor.
• Magnetic resonance imaging (MRI). This technique uses a combination of large magnets, radio frequencies and a computer to deliver detailed images of organs and other structures inside the body. A special dye that collects around cancer cells may be used to create a better picture of the cancer and show whether it has spread.
• Biopsy. To confirm the diagnosis, a doctor removes a small sample of the suspicious tissue using a needle through the skin or during surgery; the cells are then examined under a microscope.

Treatment of liver cancer

The main treatments for liver cancer are surgery, chemotherapy and radiation. In some cases, doctors recommend a liver transplant. Patients typically have more than one type of treatment. In designing a plan for your child, the doctor will consider several factors, including:

• The type of liver cancer
• Whether there is more than one tumor
• The stage of the cancer (determined by how much of the liver is affected, how abnormal the cancer cells look under a microscope, and whether the cancer has spread to other parts of the body)
• Whether the tumor can be removed by surgery
• Whether the cancer is newly diagnosed or has returned

Surgery for liver cancer

The goal of surgery is to remove the tumor while sparing as much of the liver as possible. If the cancer is confined to one area, a surgeon may be able to take only that part of the liver. The disease may be cured if the tumor is small and can be completely removed. This is possible more often for hepatoblastoma than for hepatocellular carcinoma.

Chemotherapy for liver cancer

Chemotherapy is using drugs to kill cancer cells. These substances are usually given intravenously (into a vein). Chemo may be used before surgery to shrink the tumor or after surgery to destroy any remaining cancer cells. When surgery isn't possible, chemo may be used as a stand-alone therapy.

Radiation therapy for liver cancer

Radiation therapy is using high-energy rays (usually X-rays) to kill cancer cells. As with chemo, this treatment may be used before surgery to shrink the tumor or after surgery to get rid of cancer cells that remain.

Liver transplant for liver cancer

If the cancer has spread throughout the liver, it may be necessary to replace the liver with one from a matched donor. Liver for transplantation can come from a deceased donor or a living donor.

Investigational therapies for liver cancer

Patients may have opportunities to participate in clinical trials (studies evaluating promising treatments) for hepatoblastoma. Learn more about the process and potential benefits of enrolling your child in a clinical trial.

Your child's care providers will talk to you about side effects kids typically experience during treatment. Short-term issues may include pain after surgery, nausea and fatigue during chemotherapy treatment, and a rash or other types of discomfort during radiation therapy. In addition, it's important to learn about long-term effects that may develop later in life.