Cancer of the Liver & Liver Tumours

80% of childhood hepatic tumours are hepatoblastomas, a type of embryonal tumour. The remainder are hepatic carcinomas.

In addition to hepatoblastoma and hepatic carcinoma, other types of childhood cancer can occur with the liver as the primary site. These include soft tissue sarcomas, lymphomas, neuroblastoma and germ-cell tumours. Inclusion of these tumours increases the total incidence of liver cancer in childhood by about a quarter.

Hepatoblastoma and hepatic carcinomas are primary tumours. The liver is a common site for the development of secondary tumours that spread (metastasise) from another site. These secondary tumours are not classified as hepatic tumours.

The causes of primary cancers of the liver are not fully understood. Some reports suggest associations between environmental exposures and hepatoblastoma, including parental occupational exposure to metals, petroleum products and paints or pigments.

There also appears to be an association between hepatoblastoma and low birth weight. A very small number of cases of hepatoblastoma occur in association with congenital anomalies and familial conditions.

Hepatic carcinomas are more common in countries that have a high incidence of hepatitis B. Children who are infected with hepatitis B have a higher risk of developing hepatic carcinoma than uninfected children.

Incidence

Hepatic tumours account for 1% of childhood cancers, with up to 20 new cases diagnosed every year in the UK.

Incidence of hepatoblastoma is highest in the under-3 age group, declining steeply thereafter. Hepatoblastoma is more common in boys.

Incidence of hepatic carcinoma increases with age, with the majority of cases diagnosed at 10-14 years. Boys and girls are affected equally.

Survival

Overall five-year survival from hepatic tumours is 82%.

Within this, the rate for hepatoblastoma is better at around 86%.

The outlook for children with hepatic carcinoma, however, is very poor – less than 30 per cent of children survive.

The most common symptom of a hepatic tumour is a lump or swelling in the abdomen, which can be painful. Other possible symptoms include weight loss, a loss of appetite, nausea and vomiting.

A variety of tests and investigations will be carried out to confirm the diagnosis if a hepatic tumour is suspected.

An ultrasound scan and/or X-rays should reveal the presence of a tumour in the liver.

A biopsy will be taken to confirm the diagnosis.

Blood tests will also be carried out. Most hepatic cancers produce a protein called alpha-fetoprotein (AFP), a tumour marker. It is possible to measure levels of AFP in the blood – this can be a useful indicator of whether the tumour is responding to treatment or whether it may have come back after treatment

Liver tumours need to be removed surgically. A system called PRETEXT (the ‘pre-treatment extent of disease’) uses MRI scanning to establish the extent of the tumour in the liver and to determine whether it has spread to other parts of the body.

• PRETEXT 1: one liver sector is affected and the tumour can be removed by straight-forward surgery
• PRETEXT 2: two sectors are affected and the tumour can be removed with more extensive surgery
• PRETEXT 3: three sectors are affected and the tumour can be removed with major surgery
• PRETEXT 4: all four sectors of the liver are affected and a liver transplant is required

PRETEXT 1, 2 and 3 tumours are classed as ‘standard risk’. PRETEXT 4 is ‘high risk’ and includes tumours which have spread (metastasised) to other parts of the body.

For hepatoblastoma, chemotherapy is given first – to shrink the tumour and eradicate metastatic tumours. Surgery to remove the remaining tumour will take place a few weeks after chemotherapy. Further chemotherapy is usually given after surgery to make sure all remaining traces of the disease are destroyed.

The role of chemotherapy in the treatment of hepatic carcinomas is less certain. If the tumour is not too large, surgery usually takes place straight away and chemotherapy may be given afterwards. If the tumour is too large to remove straight away, chemotherapy will be used to shrink it before surgery.

If there is cancer in the lungs – and this is not completely destroyed by chemotherapy – the lungs will be operated on first. If the liver tumour can be surgically removed, that operation will usually follow a week or two later.

A liver transplant will be necessary if the tumour involves all four sectors of the liver (PRETEXT 4). This is only possible if all the cancer outside the liver has gone. A liver transplant involves removal of the whole liver and replacement with a liver from a donor. It may be possible for a parent to donate half of their liver.

Hepatic carcinomas may respond less well to chemotherapy. For this reason other treatments such as chemoembolisation and targeted treatments may be considered.

Chemoembolisation involves giving drugs directly into the artery going into the liver.

Targeted drugs are a new group of treatments that work in a different way to conventional chemotherapy. Some drugs may cause cancer cells to die directly. Others act to cut off the blood supply to the tumour cells (antiangiogenesis). Some drugs, called multi-targeted agents, work in both ways.

Side effects and complications of treatment

Treatment often causes side effects and these will be discussed before treatment starts.

The possible side effects depend on the treatment given and the part of the body being treated but may include nausea and vomiting, hair loss, reduced resistance to infection, bruising and bleeding, tiredness and diarrhoea.

These problems are all temporary and can be minimised with good supportive care.

Follow up

Children will have regular follow-ups to check for any recurrence of the cancer and for any problems that may arise as a result of the treatment they were given.

The chemotherapy used to treat liver cancer can cause late side effects. These may include hearing problems, kidney problems and possibly heart problems. The child will have a slightly increased risk of developing another type of cancer later in life.

If the cancer comes back after initial treatment, this is known as a relapse. This may be in the liver or in other parts of the body. Relapse may be diagnosed by blood tests (before anything is seen on scans) as the levels of alpha-fetoprotein (AFP) are monitored after treatment is complete and rising levels can indicate early relapse. However, small rises in AFP may occur in the weeks after surgery, as the liver regenerates.

The prognosis and treatment options depend on where in the body the tumour recurs and the type of treatment used to treat the initial cancer.

Many children have their treatment as part of a clinical trial.

Trials aim to improve understanding of the best way to treat the cancer, usually by comparing the standard treatment with a new or modified version.

If appropriate, the child’s medical team will discuss participation in a relevant trial. Participation is optional but may offer the opportunity to receive new treatments.