What are the other Names for this Condition? (Also known as/Synonyms)

• Focal or Diffuse Small Undifferentiated Cells in Hepatoblastoma
• Mixed Epithelial and Mesenchymal Hepatoblastoma
• Well-Differentiated Fetal Hepatoblastoma

What is Hepatoblastoma? (Definition/Background Information)

• Hepatoblastoma is a malignant embryonal tumor that develops in the liver, due to uncontrolled liver cell proliferation. It is the most common type of pediatric liver tumor
• The tumor accounts for 50% of the liver malignancies in children and is considered the most common primary liver tumor in children 
• The common signs and symptoms of this malignant liver tumor include abdominal pain, nausea, vomiting, yellowing of the skin and eyes, and frequent bruising or bleeding
• A diagnosis of Hepatoblastoma is usually made through a liver biopsy that is performed, either by an open biopsy, or a core biopsy using radiological guidance
• The treatment for Hepatoblastoma is through a combination of methods, which includes surgical removal of the tumor, chemotherapy, and radiation therapy. In some instances, a liver transplantation may be necessary
• The prognosis of Hepatoblastoma mostly depends on the stage of the tumor. The lower the stage, the better is the prognosis. Also, following treatment, the tumor is known to recur in some individuals. Nevertheless, the long-term survival is reportedly around 60-70%

Who gets Hepatoblastoma? (Age and Sex Distribution)

• Hepatoblastoma liver tumor is reported worldwide, most commonly in infants and children. The tumor prevalence rate is estimated to be 1 per 120,000 (in children under age 15 years)
• It is estimated that 70% of the tumors occur by age 2 years and 90% of them by the age of 5 years. In some children, it can be congenital too (present at or following birth)
• It is important to note that some individuals into their teens may also be affected
• The condition is two times more common in males than females (2:1 male-female ratio)
• There is no known ethnic or racial preference

What are the Risk Factors for Hepatoblastoma? (Predisposing Factors)

Following are the risk factors of Hepatoblastoma:

• In a vast majority of cases, this liver cancer is seen during infancy and early childhood
• Male gender: Males are twice more likely to develop Hepatoblastoma than females
• Presence of familial colonic polyposis increases the risk by about 500 times
• Glycogen storage disease type 1a (von Gierke disease) 
• Hemihypertrophy (Beckwith-Wiedemann syndrome)
• Li-Fraumeni syndrome
• Low birth weight infants 
• Simpson-Golabi-Behmel syndrome 
• Trisomy 18 syndrome
• Trisomy 21 syndrome
• Acardia syndrome
• Presence of Wilms’ tumor (a type of pediatric kidney tumor)
• Goldenhar syndrome
• Adenomatoid transformation of Bowman capsular epithelium in kidney
• Significant excess of maternal exposure during pregnancy to metals used in welding and soldering, lubricating oils, and protective greases have been shown to increase the risk

It is important to note the following:

• Viral infections: A viral infection, due to hepatitis B or hepatitis C viruses, is NOT known to increase the risk for the condition
• Liver cirrhosis is NOT a risk factor for the tumor. The development of scarring in the liver is termed cirrhosis; it can occur due to a variety of causes

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Hepatoblastoma? (Etiology)

• The exact cause and mechanism of Hepatoblastoma formation is unknown. These tumors are thought to occur spontaneously
• Some reports indicate that they may occur due to genetic defects, as certain chromosomal aberrations have been noted

What are the Signs and Symptoms of Hepatoblastoma?

The common signs and symptoms of Hepatoblastoma include:

• Abdominal pain, which can be either due to tumor growth, or due to metastasis of the cancer within the abdomen
• Weight loss and fever
• Nausea and vomiting
• Jaundice; yellowing of skin and eyes, due to accumulation of bilirubin caused by liver failure
• Enlarged abdomen due to accumulation of fluid within the peritoneal sac, called ascites
• Easy bruising or bleeding that occurs as a result of liver failure. The liver is responsible for making clotting factors that help with the coagulation of blood. When Hepatoblastoma results in liver failure, the body has lesser amount of clotting factors, thereby resulting in easy bruising or bleeding

In many instances, Hepatoblastoma is often silent during the initial stages, without any significant signs and symptoms. Besides, not all tumor affected individuals notice the symptoms resulting in a delayed diagnosis.

How is Hepatoblastoma Diagnosed?

A diagnosis of Hepatoblastoma is made using the following tools:

• Physical examination with evaluation of the patient’s medical history
• Various blood tests, including complete blood count (CBC) and liver function tests. The blood test may show elevated serum alpha-fetoprotein (AFP) levels
• Radiological studies: Ultrasound of the abdomen and CT/MRI scan of the abdomen. Mean size of the tumor is 10 cm (with tumor size range being 3 to 20 cm). There may be more than one tumor in the liver in around 15% of the infants and children
• Liver biopsy: The biopsy of liver of the abnormal tissue is examined under the microscope by a pathologist to arrive at a definitive diagnosis. Occasionally, the pathologist may perform additional tests on the tissue to arrive at a definitive diagnosis

The biopsy of liver is performed using any of the following methods:

• Fine needle aspiration (FNA) technique: FNA biopsies are not helpful in establishing a definitive diagnosis in many cases, and hence, a core or open biopsy is preferred
• Core needle biopsy of liver
• Open biopsy using wedge liver resections

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Hepatoblastoma?

Following are the possible complications of Hepatoblastoma:

• It can affect the functioning of the liver, resulting in liver failure
• The Hepatoblastoma tumor may spread to other parts of the body due to metastasis (spread of the malignancy). Metastases to adrenal glands, bone marrow, brain, lung, and regional lymph nodes have been reported
• Recurrence of the tumor following treatment/surgery
• Complications may arise during chemotherapy and radiation therapy, due to the toxic medication or radiation effect

How is Hepatoblastoma Treated?

The healthcare provider usually arrives at a treatment plan, based on each individual’s specific circumstance/condition. The treatment measures for Hepatoblastoma may include the following measures:

• The treatment of Hepatoblastoma depends on the stage of the tumor. During the early stages, when the tumor is confined to the liver, an excision of the tumor generally results in a cure
• With higher stage tumors, when it has metastasized to other regions or body parts, chemotherapy and/or radiation therapy in addition to surgery may be considered
• In some situations, a liver transplantation may be a treatment option
• Post-operative care is important: A minimum activity level is to be ensured until the surgical wound heals
• Follow-up care with regular screening and check-ups are important

How can Hepatoblastoma be Prevented?

There are no methods to prevent Hepatoblastoma. However, following are a few steps to reduce the risk for the condition:

• In case a family history of certain genetic disorders, appropriate genetic counseling will help assess risks, before planning for a child
• Regular medical screening at periodic intervals with blood tests, scans, and physical examinations, are mandatory for those who have already endured the tumor. This is due to its metastasizing and recurrence potential. Often several years of active vigilance is necessary

What is the Prognosis of Hepatoblastoma? (Outcomes/Resolutions)

The prognosis of Hepatoblastoma depends on the stage of the tumor. In some cases, the prognosis also depends on the histology described in the pathology report.

• With lower-stage tumors, when the tumor is confined to the liver, the prognosis is usually excellent with appropriate therapy
• In higher-stage tumors, such as tumors with metastasis, the prognosis is usually poor
• Long term survival is stated to be around 60-70% and most recurrences are detected within 3 years of original diagnosis and treatment

Additional and Relevant Useful Information for Hepatoblastoma:

According to pathology classification, there are different subtypes of Hepatoblastoma and these are described below:

Epithelial Hepatoblastoma (constitute 56% of the tumors):

• Well-Differentiated Fetal Hepatoblastoma (31% of the tumors)
  • Hepatoblastoma, Epithelial type, purely Fetal Pattern (Mitotically Active)
  • Hepatoblastoma, Epithelial type, purely Fetal Pattern (Mitotically Inactive)
• Embryonal and Fetal Hepatoblastoma (19%)
• Hepatoblastoma, Epithelial type, Macrotrabecular Pattern (3%)
• Focal or Diffuse Small Undifferentiated Cells in Hepatoblastoma (3%) 

Mixed Epithelial and Mesenchymal Hepatoblastoma (constitute 44% of the tumors):

• Hepatoblastoma, Mixed Epithelial and Mesenchymal type, with Teratoid Features
• Hepatoblastoma, Mixed Epithelial and Mesenchymal type, without Teratoid Features
• Hepatoblastoma, Rhabdoid type
• Hepatoblastoma, other subtype