Hepatoblastoma
Hepatoblastoma is a very rare cancerous tumor that originates in the liver. The liver is one of the largest organs in the body. The primary functions of the liver include filtering and storing blood. The liver consists of right and left lobes. Most hepatoblastoma tumors originate in the right lobe.
This disease primarily affects children from infancy to about 5 years of age. Most cases appear during the first 18 months of life. Hepatoblastoma cancer cells can spread (metastasize) to other areas of the body. The most common sites of metastasis are the lungs, into the abdomen and abdominal structures, and rarely to bone, the central nervous system, and the bone marrow.
Anatomy of the liver
The liver is located in the upper right-hand portion of the abdominal cavity, beneath the diaphragm and on top of the stomach, right kidney, and intestines. Shaped like a cone, the liver is a dark reddish-brown organ that weighs about three pounds.
The liver consists of two main lobes, both of which are made up of thousands of lobules. These lobules are connected to small ducts that connect with larger ducts to ultimately form the hepatic duct. The hepatic duct transports the bile produced by the liver cells to the gallbladder and duodenum (the first part of the small intestine). The liver regulates most chemical levels in the blood and excretes a product called bile, which helps carry away waste products from the liver.
What causes hepatoblastoma?
Although the exact cause of liver cancer is unknown, there are a number of genetic conditions that are associated with an increased risk for developing hepatoblastoma, including Beckwith-Wiedemann syndrome, hemihypertrophy, and familial adenomatous polyposis. Other genetic conditions associated with liver cancer include several inborn errors of metabolism such as tyrosinemia, glycogen storage disease type I, galactosemia, and alpha1-antitrypsin deficiency.
Children who are exposed to hepatitis B infection at an early age, or those who have biliary atresia, are also at increased risk for developing hepatocellular carcinoma. Some hepatoblastomas have genetic alterations in tumor suppressor genes, which would explain the uncontrolled cell growth.
What are the symptoms of hepatoblastoma?
The following are the most common symptoms of hepatoblastoma. However, each child may experience symptoms differently. Symptoms may vary depending on the size of the tumor and the presence and location of metastases. Symptoms may include:
- A large abdominal mass, or swollen abdomen
- Weight loss, decreased appetite
- Abdominal pain
- Vomiting
- Jaundice (yellowing of the eyes and skin)
- Fever
- Itching skin
- Anemia (pale skin and lips from decreased number of red blood cells)
- Back pain from compression of the tumor
The symptoms of hepatoblastoma may resemble other conditions or medical problems. Always consult your child's physician for a diagnosis.
How is hepatoblastoma diagnosed?
In addition to a complete medical history and physical examination, diagnostic procedures for hepatoblastoma may include:
- Biopsy. Sample of tissue is removed from the tumor and examined under a microscope.
- Complete blood count (CBC). Measurement of size, number, and maturity of different blood cells in a specific volume of blood.
- Additional blood tests. May include blood chemistries, evaluation of liver and kidney functions, and genetic studies.
- Multiple imaging studies, including:
- Computed tomography scan (also called a CT or CAT scan). Diagnostic imaging procedure that uses a combination of x-rays and computer technology to produce cross-sectional images (often called slices), both horizontally and vertically, of the body. A CT scan shows detailed images of any part of the body, including the bones, muscles, fat, and organs. CT scans are more detailed than general x-rays.
- Magnetic resonance imaging (MRI). Diagnostic procedure that uses a combination of large magnets, radiofrequencies, and a computer to produce detailed images of organs and structures within the body.
- X-ray. Diagnostic test which uses invisible electromagnetic energy beams to produce images of internal tissues, bones, and organs onto film.
- Ultrasound (also called sonography). Diagnostic imaging technique which uses high-frequency sound waves and a computer to create images of blood vessels, tissues, and organs. Ultrasounds are used to view internal organs as they function, and to assess blood flow through various vessels.
- Bone scans. Pictures or x-rays taken of the bone after a dye has been injected that is absorbed by bone tissue. These are used to detect tumors and bone abnormalities.
- Alpha-fetoprotein (AFP) test. Alpha-fetoprotein (AFP) levels in the blood can be used to diagnose and follow response to treatment.